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Home My WebLink About790409.tiff KEF,NESBURG MINE SITE _ a :2, ttio AMERICAS FINE EIGHT BEER ADOLPH COORS COMPANY • GOLDEN. COLORADO • t �T-- t 4 N. alemeLii"" ses 7 7O 40 9 /-3w/i 3 ENVIRONMENTAL DOCUMENT KEENESBURG MINE SITE WELD COUNTY , COLORADO prepared by Regulatory Affairs Department Adolph Coors Company 1979 TABLE OF CONTENTS I. INTRODUCTION 3 II. THE SITE AND SURROUNDING AREA 5 A. Location 7 1 . Ownership 7 2. Deposits History 7 3. Special Aesthetic Values 10 4. Topography and Drainage 10 5. Overburden 11 B. Socio-Economic Characteristics 14 1 . General 14 2. Demography 14 3. Employment Status 19 4. Income and Poverty Status 19 5. Housing 22 6. Education 22 7. Community Services 28 C. Land Use 30 1 . General 30 2. Projected Land Use 36 3. Transportation 36 4. Recreation 44 D. Archaeological and Historical Sites 52 1 . Regional 52 2. Mine Site 54 E. Geological Characteristics and Physiography 55 1 . Physiography 55 2. Geology 55 F. Hydrology 58 1 . General Hydrology of the South Platte Valley . 58 2. Ground Water 59 3. Hydrology of the Keenesburg Proposed Site . . . 59 G. Climatology 73 1 . Regional Climate 73 -i- H. Terrestial Ecology 78 1 . Soils 78 2. Vegetation 93 3. Wildlife 97 4. Reptiles and Amphibians 100 5. Insects and Vectors 101 I. Aquatic Ecology 102 III. PROPOSED,MINE PLAN 103 A. Facilities 103 B. Mining Plan and Reclamation Plan 104 1 . Coal Processing Operation 104 2. Mining Plan 104 3. Reclamation Plan 109 C. Pollution Control 112 1 . Water 112 2. Domestic Waste Treatment 112 3. Air Pollution Abatement 112 IV. IMPACTS OF SURFACE MINING OF WELD COUNTY AREA 113 A. Impacts of Socio-economics 115 1 . General 115 2. Demography 115 3. Employment 116 4. Economics and Income 116 5. Housing 118 6. Education 118 B. Impacts on Land Use 119 1 . General 119 2. Projected Land Use 119 3. Transportation 119 4. Recreation 119 C. Impacts on Archaeological and Historical Sites . . . 120 D. Impacts on Hydrology and Water Quality 121 E. Impacts on Air Quality 122 1 . Present Air Quality 122 2. Effects of Mining 122 -ii- F. Impacts on Wildlife 124 1 . General On-Site Impacts 124 2. General Off-Site Impacts 124 3. Expected Impacts on Vertebrate Groups 124 G. Noise Impacts 126 H. Visual Impacts 127 I . Water Use Impacts 128 V. BIBLIOGRAPHY 129 APPENDIX A RESEARCH STUDIES FOR THE PROPOSED SITE 1 . Soil and Vegetation Inventory Revegetation Research Keenesburg Area 2. Water Resources and Impact Evaluation for a Proposed Mine Site, Weld County, Colorado APPENDIX B LETTERS OF COMMENT 1 . Colorado Department of Natural Resources Division of Wildlife, 6 October 1978 2. Cultural Resource Consultants Inc. , 10 November 1978 -iii- I. INTRODUCTION I . INTRODUCTION Large amounts of low-sulfur, sub-bituminous coal underlie several eastern Colorado counties. Most of this coal is found in the Laramie formation which underlies the surface in the synclinal basin. Many mines in Larimer, Weld and Boulder Counties extensively mined the forma- tion for its coal by conventional underground methods. These supplies of coal have dwindled to a point where there is now only one active mine in the region. In Weld County considerable coal was mined by underground methods from the Laramie formation. Coal mines were located near Keota, Briggsdale, Cornish, Galeton, Eaton and Platteville. Additional coal mines 6 to 9 miles south of Kersey on Highway 37 are closest to the site of the proposed Keenesburg mining area. These mines were named Sunset, Christenson, Trent, Black Nugget, Diamond, Bohlander, Casselman and Buddy. All of these mines extracted coal by underground methods. Due to the need for low-sulfur solid fuels to meet stringent envi- ronmental standards, a search has begun for other local sources of coal deposits lying closer to the surface. Some promising deposits have been located in south central Weld County. In an effort to properly evaluate possible mining of this coal , Adolph Coors Company has implemented a progressive study to develop a complete Environmental Impact Assessment (EIA) of the proposed surface coal mine. This assessment is a culmination of months of field work, data collection and investigation into the site and its surroundings. Adolph Coors Company's Regulatory Affairs Department has completed this report with the assistance of the Colorado State University Environmental Resources Department. Adolph Coors Company wishes to express its sincere appreciation for the thorough and competent field studies performed by C.S.U. and for the fine cooperation extended and data provided its research team by Weld County Colorado State Health Department and the Colorado Natural Resources Department. —3— II. THE SITE AND SURROUNDING AREA II. THE SITE AND SURROUNDING AREA A. Location Weld County, incorporated in November of 1885, is located in the northeast portion of Colorado. The third largest in the state, Weld County contains 4,004 square miles in the Great Plains area approxi- mately 40 miles east of the Continental Divide. Weld County is bounded on the west by Larimer and Boulder Counties, on the east by Logan and Morgan Counties, on the south by Adams and Morgan Counties, and on the North by the Wyoming border. The South Platte River and Interstate Highway 76 cross the county from east to west. Interstate 25 crosses from north to south. Urban development has been primarily in the south- west portion. At the present time, approximately 81 .5 percent of the land in the county is in private ownership. State-owned lands total 8.0 percent, county and municipal lands amount to 0.4 percent and 10.1 percent of the land is owned by the Federal Goverment. The Keenesburg Mine Site is an area of privately-owned and state- leased lands in south central Weld County and is located approximately 45 miles north and east of Denver on Highway I-76. Refer to Map #1 . The area is approximately 5 miles directly north of the town of Keenesburg, Colorado. None of the area lies within any federally-owned or controlled lands. 1 . Ownership The site encompasses an area in Weld County T3N, R64W Sections 25, 26, 35, and 36. Refer to Map #2. Coors secured mineral leases on these lands from several private owners as well as from the state. At present, Coors Industries operates and maintains numerous natural gas wells in this area along with a natural gas pipeline to its brewery in Golden, Colorado. 2. Deposits History As indicated, the Counties of Boulder, Larimer and Weld are underlain with coal seams in the Laramie formation. The dry, arid regions of eastern Weld County have spotty areas of "pocket" coal which lie close to the surface. These pockets of coal occur where the action of the water in the freshwater lagoons has concentrated the carbonaceous materials to minable thickness. The lagoons were the fringes of a great, shallow sea which once covered the area. Vegetation grew around the edges of the sea and developed into pockets of coal . The pockets of coal are generally eliptical in outline. There are several coal seams in the Laramie formation and minable coal can occur in any seam. The coal seam proposed to be mined is the No. 7 Seam or youngest seam in the Laramie Coal Group. -7- MAP 1 Location of Proposed Keenesburg Surface Mine I N LARIMER WELD US 85-87 Greeley US-34 Proposed Mine Site 1-25 Roggen MORGAN R G A N • Keensburg 1-76 ADAMS DENVER -8- ADJACENT PROPERTY OWNERS 22 '. I '\ 2 24 O vK �� 1 _I ' 7 31 2 I\ aM Pc J _'r 4805 V� Vie. IV � �� `�I ' �'- /.\',,,,3 27 �i �25y �ISt W '. \� o ;. 4868 `o> - �-• ,` \:\ "� o O d„ I \ o i ` WinCmrllb\ \I (f` �� 4183 1° r . 3\ 0 ' , 4864 4834+ '� ,�-- `° 11 //( . 11 �* � '4843 �� W lif) 490- AI '' -'' o (B�3 /) \ I -4800 „..,,,, o,...... / 34 35 l 36r 3�0 .ti,., „ , ,t.,_ , ,,. : „,_ ... .„---_-- ,-\ � z.,„ `� <. eo p_ c� op r a P \° A I / T N .,alt ( o�, - 3 +4916 \ 4B8 +4853 1 Q d �I8/4/ T, _ 2 � r' ® °� o / I� 4 1, / `1 JY ri, .6-` O r - - 'Ne0 I \ m / a 1 . State of Colorado 2. Two E Ranches, Inc. , 600 Greeley National Bank, Greeley, Colorado 80631 3. L. F. Ranches, 707 Seventh Avenue, Greeley, Colorado 80631 4. John Cuykendall , Cuykendall Herefords , Inc. , Roggen, Colorado 5. Alfred and Mary Heyde, Corde, Arkansas 72524 9a • SURFACE AND MINERALS OWNERSHIP MAP MAP 7Tc 22 VjJ`-.i If :\ 23 ---.24oNr V ci lc _ Irt\ �� Li Pc 1 1 CJ • :S. ° :n A %R. o i — a \ (1\....j‘tri \ -15 ci \ "\- ( -, A' --ts • 27 1J;1 25;' ?, J � l . \11) ) �� ,L � V A A� v0 pi _ �� i J o A\\c•- ,j\_ o Windmill cam. FRB] C, -4864 \ _ \ (., (2,i ' 1/ECPf° � A ,r4B43,� I A �or‘o \� a o�B3 0 i 4910_1 • L'') \ L--�. ."‘163,/,' ,� i C c�iN,,/,,- � ) • r) pp 4793 III uB00 6 ��.s , , .- 35 v , .V A F 1 A 's o Po SO o „% Q / off\ / T3N r 49/6:. 4683. A 'f : ,4853 1 0 D \;t1+.4 �8/a T I i ° � oi V Ji/T L- ))/N ` O 2 `/ I \ 1 S , ( c, C SURFACE OWNER MINERAL OWNER • O Alfred and Mary Heyde Alfred and Mary Heyde OTwo E Ranches, Inc. Two E Ranches, Inc. , etal . O Two E Ranches, Inc. Rock Springs Royalty Company O4 L. F. Ranch Company/Adolph Coors Rock Springs Royalty Co. & L. F. Ranch Co. O State of Colorado State of Colorado -9- 3. Special Aesthetic Values The proposed surface mine is situated in a rolling, sparsely- vegetated, semi-arid plain. On clear days the eastern Front Range of the Rocky Mountains (nearly 50 miles away) is visible from the site. Snow-capped peaks in spring and early summer add to the topographic contrast of plains and mountains. Lizards, rabbits, birds, and other small mammals make their homes in the sparse vegetation. In the fall the area browns from lack of late season moisture, and plant life waits in dormancy for spring. The blue hue of sage against the browning of sand and plains grasses contributes to a sense of calm and solitude. This rural ranching community is only interrupted by a concrete thoroughfare linking the mid-plain city of Denver to other towns farther east. Instead of the noise and smoke of large cities, the land has the same raw, plain beauty which greeted the pioneers a century ago. 4. Topography and Drainage The topography in the north portion of Weld County is gently undulating to rolling. South of the South Platte River valley it is rolling to hummocky. The river floodplain is level to gently undulat- ing. Elevations in the county range from a low of approximately 4,400 feet above sea level at the point of egress of the Pawnee Creek to highs of approximately 6,200 feet above sea level in the northwest portion of the county. In addition to the South Platte, important streams in Weld County include the Cache La Poudre River, Vrain Creek, Crow Creek and Kiowa Creek, all of which flow into the South Platte River. Several water impoundments have been developed in Weld County. The larger reservoirs include the following: Empire, Riverside, Milton, New Windsor, Lower Latham and Black Hollow Reservoirs. The rolling ridges of the mining area are primarily blow sand with sage brush and prairie grass for vegetation. The proposed mine site slopes in two drainage patterns. Refer to Map #3. To the west the area slopes to Box Elder Creek which has an intermittent stream flow usually after summer thunderstorms. Box Elder Creek eventually joins with the South Platte several miles to the north. To the east, the surface water would flow to Ennis Draw. Historically this draw has no surface evidence of water flow, but precipitation is absorbed by the porous surface sands and creates a subsurface flow that supports the salt grass meadows of Ennis Draw. This subsurface flow in Ennis Draw is discharged into Sox Elder Creek to the north of the proposed area. Comparing the Keenesburg Mine Site area to the surrounding agricul - tural fields several miles away, it is situated in a moderately high plateau. The proposed site is excluded from the the Central Colorado Water Conservancy District for its lack of 'potential for water develop- ment", according to a telephone conversation with the Director of the Weld County Conservation District. The semi-arid area gains its moisture from severe, wind-whipped snowstorms in winter and thunderous rains in spring. In recent years tornadoes have disrupted the sparse vegetation. -10- 5. Overburden The surface of the proposed surface mining area north of Keenesburg consists of wind blown sand, which covers the area to depths of 17 to 20 feet. This sand is tan to brown on the surface but lightens in color with depth, and many times is yellow above the clay. The sands generally became coarser with depth. Under the sands is a moist, sticky, tan clay that averages 4 to 5 feet in thickness. These clays may contain calcite crystals. Beneath the clays, the soft laminated shales, siltstones, or mudstones predominate. They frequently change in color and thickness but usually are gray in color and range from thin to thick lenses. Above the coal seam the shale lenses change in color to dark gray or black, but they are usually thin. In the thicker overburden, a very soft, tan, sandy shale is present. Persistent to moderately persistent stringers of tightly cemented, light gray, sandstone occurs in lenses, 6 inches to 4 feet in thickness, between the shales and siltstones. A maximum of two sandstone stringers or lenses occur in one locality. -11- PROPOSED MINING ACTIVITY AREA N , it \--\\__ ''''''',„ \ ,, 61'\---\ z , \` 5 I p c 9,5> \ %� o \ 4e,rr I \ I• v61.> \\ v ' \' �� \ L Ba0 • $ i s D syro il:::, h r--i \ � / \ I - - 6' \a0 0 O r Q 9 •I 0 Q 49 � , q `� � po ,o s 0 _ 00 Io / - O 0 , �! �\ i V t in % f3 \ ©tie ° r., o iL--) le ,_ ," MAP 3 Close-Up of Proposed Mining Area and Drainage Pattern _,9_ B. Socio-Economic Characteristics 1 . General The project area is defined as that area directly north of Keenesburg, Colorado. However, the social and economic developments stemming from this project would affect areas to the west as well as areas farther east. The counties potentially affected by this project are Weld (the primary county) and Morgan and Adams (secondary counties) . Cities and towns surrounding the project would supply a work force and would benefit from such a project by additional funds which would aid each community's economic base. Moving from west to east, some of the more directly affected communities and their respective 1970 census populations are: Greeley (38,902), Hudson area (513) , Kersey (474) , and Keenesburg (437) . Table II-1 shows the current population of Weld County (1970) and its subdivisions as well as the percent of change from 1960 to 1970. The general characteristics of these communities vary widely with Greeley at the upper extreme in population, diversified economic base and employment, and range of services. Keenesburg at the lower end has few residents and almost no central economic base or service structure. Greeley is a thriving , middle-sized Colorado community. Keenesburg and Kersey are small , modest communities with limited services and no light industry. 2. Demography Population growth is influenced much more by other factors than by water supply. A generally desirable location wil attract people and a relatively undesirable place will lose population. All kinds of environ- mental attractions induce people to resettle. A favorable clima5e, lakes, and open country generally are attractions by themselves. Other inducements include ore jobs, lower crime rates, and certain types of ethnic distribution. In relation to metropolitan areas, water resource investments are more likely to be made in response to needs and have more often followed residential development, highway construction, and 1 J.E. McKee and T.R. Rice, "Clouds in the Crystal Ball ," Journal of American Water Works Association, May 1964, pp.265-269, as cited in Final Environmental Statement, Narrows Unit, South Platte Division, Colorado (Bureau of Reclamation, U.S. Department of the Interior, 1976) . 2 Rivkin/Carson, Economic Development and Water Resource Investments, Report to the Bureau of Reclamation (Washington, 1973) as cited in Narrows Unit. 3 Rivkin/Carson. 4 "The Use of Water Supply to Restrict Regional Population Growth," Water Newsletter, 13 June 1974, as cited in Narrows Unit. -14- TABLE II-1 POPULATION OF COUNTY SUBDIVISIONS Percent 1970 1960 Change WELD COUNTY 89,297 72,344 23.4 Ault Division 3,747 4,074 -8.0 Ault town 841 799 5.3 Nunn town 269 288 18.0 Pierce town 452 424 6.6 Eaton Division 4,903 5,098 -3.8 Eaton town 1,389 1,267 9.6 Severance town 59 70 -15.7 Erie Division 2,183 1,669 30.8 Erie town (Part) 1,083 875 23.8 Evans Division 7,538 6,553 15.0 Evans town 2,570 1,453 76.9 Garden City town 142 129 10.1 Rosedale town 66 70 -5.7 Fort Lupton Division 7,814 5,222 49.6 Fort Lupton town 2,489 2,194 13.4 Frederick Division 3,101 2,172 42.8 Dacono town 360 302 19.2 Firestone town 570 276 106.5 Frederick town 696 595 17.0 Greeley Division 38,902 26,314 47.8 Greeley city 38,902 26,314 47.8 Grover Division 555 654 -15.1 Grover town 121 133 -9.0 Johnstown-Milliken Division 4,944 4,685 5.5 Johnstown town 1,191 976 "22.0 Mead town 195 192 1.6 Milliken town 702 630 11.4 *Keenesburg-Hudson Division 3,028 3,067 -1.3 Hudson town 518 430 20.5 Keenesburg town 437 409 4.4 *Kersey-Gill Division 3,409 ---- Kersey town 474 378 4.5 La Salle-Gilcrest Division 3,746 3,585 4.5 Gilcrest town 382 357 7.0 La Salle town 1,227 1,070 14.7 Platteville Division 1,851 1,785 3.7 Platteville town 683 582 17.4 Rayner Division 789 1,000 -21.1 Keota town -6 13 -53.8 Rayner town 68 91 -25.3 Windsor Division 2,785 2,788 -0.1 Windsor town 1,564 1,509 3.6 Source: U.S. Bureau of the Census. 1971 U.S. Census of Population, 1970 Number of Inhabitants, Colorado. U.S. GPO, PC (1) -A7-COLO, Washington, D.L. * Denotes Divisions in and around project area. -15- and economic growth.5 People are encouraged to remain in rural areas which have water available for other uses, such as irrigation for crops. Among the land use concerns of this region is the need for water.7 Usually the availability of additional water in rural areas has decreased the rate of outward migration. Water helps intensify agricultural productivity per acre, allows diversity in crop production, and restores the economic viability of small farm units run by individuals. When people remain in these areas, others tend to migrate in to establish service-oriented businesses. Towns start to grow along with the local economies. Weld County is partially suburban. Its major city Greeley is growing rapidly and has a relatively young population. Greeley provides the bulk of Weld County's urban population. The county's rural population has increased only slightly, and some of this increase is probably suburban in nature. About one-half of Morgan County, dominated by its county seat Fort Morgan, is urbanized. Morgan County is losing rural population and has maintained essentially static urban populations from 1960 to 1970. The population is older than Weld County and average age is increasing. The City of Fort Morgan is essentially static and is experiencing outmigra- tion, particularly of the young . With the possible exception of the Greeley area, these rural areas are exporting young people, especially those just out of high school . Some elderly people also move into local towns or out of the area. The cities too are experiencing outmigration of youth, but at a lesser rate than rural areas. Weld, Morgan, and Adams Counties include a substantial population of Spanish-speaking and Spanish-surnamed Americans. Refer to Table II-2. There are almost no blacks in the study area. The project area has strong communities of German, Swedish, Russian, Italian, and Mexican Americans. Immigration from other states has been concentrated in the Fort Morgan area but has not generally been very strong. The immigration which has occurred has been dominantly from the north-central states. The mine project will employ approximately 40 full-time workers. Refer to Table II-3. Of these workers, most will be hired locally from the surrounding towns of Keenesburg, Kersey and Roggen. Other workers may need to relocate or commute from their present locations. Additional workers may be required as Coors reclamation program begins. 5 Rivkin/Carson. 6 A Land Use Program for Colorado, Report by the Colorado Land Use Commission (Denver, undated) as cited in Narrows Unit. 7 A Land Use Program for Colorado. -16- C O 01 01 M r n 4- 0 • r 0 t -= Cr) N- r tD a N O r d' n L 0 a c0 e a N N 00 • M N 01 L U) It 0 N- 01 n W et LO N Q N 04 N IN N. N O IN C rn Iti0 2 Q 2 2 2 L al M U) \ \ \ \ ) O U) 0 O CO Z = = = = L a M y I. r 04 I- 4-1 .y S- 0 0 La- C) F- Z S U) N- O a U() tO n 01 N 0 • - N n N • Cr) 01 CO M CO U) N in^ N I--I 2 O N n CO 04 N N r W 0 J I-+ [C 2 N I- ---i C W I- U r It 2 -N 04 ( • N ^ O1 01 • 01 01 C n w O N 01 Q IL 01 Cr) CO N M = N a 04 L I U U L Lb M r M U M r M I 0 = L d VI Q C C •0 co 2 ch W L N n aN a C •l C' 01 n ^ r O N It 03 CO N 0 n 03 N. CO W 04 a a N n 0 U) CO a) W M n j C c a b N J N _ N C 1. 1.0 1 y •.- Ln 0 > a NN 00 0 Z N LO Or•rLO r = y 01 CO N A CO L Or O V v L q' cm r L N s- 0 Z N C C C) > 01 4- C a) 0 O^ cri Q 0 0 O 1.1 0 0 Q 0�„1 C N Y = Ss L -4) N C L s' d 0 = 1.0 p 4) N U g a '' b � Et a C e � B. :or E E +) 0E O N 7 7 L0 N 0 G) = = 0 d L X Z Z O_ 0- 5 = = ✓) -17- TABLE II-3 GEOGRAPHIC DISTRIBUTION OF WORKERS EMPLOYEES NO. LOCAL COMMUTERS MOVING INTO AREA Mine Operators 35 25 5 5 Reclamation 5 3 2* - * * Indicates possible relocation of some reclamation people into the area There will be only a slight additional population rise with this project -18- Labor force size and composition is closely tied to the character- istics of the population, as well as to economic cycles and developments in lifestyles such as family formation, and retirement patterns. The trends nationally as well as in Colorado indbcate incresing labor force participation rates during the coming years. 3. Employment Status Employment rates in 1977 indicate the same type of relatively healthy economic activity implied by the median income data. The unemployment ratio for Weld County was only 3.9% in 1977, compared to a national average of 4.62%. The labor force of the county essentially was fully employed in 1970. Unemployment rates of 2% or less reflect the typical temporary unemployment of people moving from one job to another. All .minority classes reflect a slightly higher percentage of unemployed workers. There exists a small working force readily avail- able. Some skilled and semi-skilled laborers must either be bid away from existing employment or recruited from outside areas. Table II-4 shows the employment status of available employees in Weld County. The major employers in Weld County are Eastman Kodak, Monfort of Colorado, State Farm Insurance and the University of Northern Colorado. Other employers include the manufacturing firms of Bayly, Central Houses, Fort Lupton Canning, Agland Co-op, Beatrice Foods, Farr Farms Wholesale, and Cowan Concrete Construction. Service-oriented businesses include Weld County Hospital , Mountain Bell Telephone Company, Home Power & Light, Aims Community College, United Bank of Greeley, First of Greeley, Greeley National Bank and Shupe Brothers Trucking. 4. Income and Poverty Status In the study area Weld County has the highest median family income. Morgan County has the lowest per capita income and the highest percentage of families below poverty level . Families living in Morgan County below poverty level havg the lowest rate of public assistance income for the subject counties. In all counties the percentage of families below poverty level is substantially higher than the 9.1 percent reported for the entire state of Colorado. Table II-5 indicates the income and poverty status of the three counties around the study area. Approximately one-fifth of all families in Morgan County below the poverty level are Spanish in derivation or surname. Of all Spanish families in Morgan County, one-third are shown as being below poverty level , and of these families most receive public assistance income. In 8 Greeley Human Resources Report (Greeley Human Resources Commission, undated). 9 Final Environmental Statement, Narrows Unit, South Platte Division, Colorado (Bureau of Reclamation, U.S. Department of the Interior, 1976), III, 127. -19- * N A -n 3 m pp o on \ \ a O 9 co=Lc.or R £ N y yANm£y y2•Nm£•"I r -1aNmZ-I 2 frll Ct va •Al 0 C T o a A0 r o a A0 0 —1-0 —I 0 0 m -1 CD CO R ANN ft m AA Cu 0 rAnm O N A Zo �r 0. 3 0 co =n r 0 0 =n tt 0 =0 r-a en 0 n y1 3 0 O N 0 x0 O A0 O AM A x O S33 22220 A o I. 81 3j, 3(b Alb N In =a rO_ = CO J1 = J12 J •1x x O.AO J O 2 O 2 0 2 0 I.0 r n 2 r 01 n A mm r. 1 a•c .4n s o. x• r tl r r n r r 19 r J 0 01 0. N 1 In 01 In10 Into •< roO a \ CO Na `° \ 2 0,.a ' N r O J a = 0IOa \ \ v pJ 0 ry 0 2 a 01 2 = a -.a 2 Cl. n Co r Na Na A A A A 01 V V 00 >.. 00 1 J C O.0 u 01AA La (0 4/01 tON CM AO 0101 O.A. -A O R SO W A O TA AAW.O AAV1000 Fr_ = = VVA10 t0N b...��VW A 00,N201T -ID r n 02 III 0 � 3 C DI = c O. 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J 0+ m ti 6< CT •• •• . 0 0 a 6 I -m m Co al Co 0 on N a tJ N 6-a c T 0, N) -0 2 N �7 NV) Co n Nac a 3 O o o • 0 cr F N t0 01 N _ 1/40 --h(D N • 0, C+ N) al V 9 1/40 w (D Z N = -0--A -.I. T -0 n N (D O m C+ 0 m O —I _ G < N S 9 T n N) A (Dew . () o _. T -J.•••a CD O N) w 0 cF c+ 7 .a• 7 Cu an —•cC SO (D 0- bR 7 \ N O N O 0. 6 7 a - _ I (D (D O G) N) -O T 0 0 CD ---' Cr 0 0 < 6 1/40 (D T sil N O 0 �• -n -O -0 t< 7 N S a T T N = C) Cn VI E -.. J. n (, C+ n (D an -O •✓(D 4, (D N o -• (..) o, -• C+ C •J•7 CO 7 CT 9 -1, 0, 0- (D c+ 0 c+ -+ (D 0 7 -•N N N O U) T n �• 0 0 O 0 •-i- 0- m co n • • I -h m o, 10 to u, 0 1/40 -h N f 0 a cr 4, Co -o c+ -• T -0 ..... '--M1 se c m S 7 0 m N 3 Co 0 < 0! 0 3 T Co • m 7 O i •n ...I.CO w CT V ^� �•�CD H+ Cr N O -N -5 0C < S N o 41 CO N) O N O T -a• n m m - b 0 = N < T N 0 = J r • N a V N LO 0 0 2 6 _, t0 m to - y, to m 01 -s T 9 O N c O J -O 7 n - N CD N N N) 0. 7 co m 4A N .• O n -0 T _ —, Cr V_ (w) 0, O N) N) A O t< Cu O 0, 0 a Cu • 7 O t0 A 0 O n 6 T CO CO V t 0 0 O N t00 C (yq. v a = C. c CO w A {yq 0 -h --a 01 O -0 ---, F "O -O Cr! O 1/40 T am —mm O co + < < N C+ T T V, m y • N S N n V CO O T O m 0 —, V V V —• c+ -•• 7 7 m S 0 N CY al 1/40 w < P+ n m 7 • J -21- all counties the median per capita income of0Spanish families is consid- erably lower than for the total population. In counties and school districts, with one exception, the highest percentage of income per families is in the $6,000 to $10,000 range. The exception is the Platte Valley School District where Vie highest percentage of income is in the range of $3,000 to $6,000. Table II-6 shows the total number of families in Weld County and their income status in each category. 5. Housing In the communities from Greeley to Fort Morgan, the market for adequate housing is extremely tight, with some low income and/or young families living in inadequate housing. Because of the housing shortage, inhabitants have made liberal use of mobile homes. Table I1-7 shows the estimated number of housing units started in the three-county region from 1969 to 1976. The availability of houses in the area increases yearly due to new housing starts. However, most of these starts are in established, high population areas around Greeley, Fort Morgan and cities of Adams County. Mobile homes in the region have also increased. Refer to Table II-8. 6. Education A study of the aglesex structure of the school districts yields the following conclusions: 1 . There is evidence of a severe loss of youth after high school , marked in all areas, but less severe in the Greeley and Fort Morgan areas. 2. Fort Morgan has a substantial community of older people. Table II-9 shows persons enrolled in school during 1970 between the ages of 3 and 34 years of age by grade level and by county. Weld County has the largest number of students enrolled in school between the ages of 3 and 34. Table II-10 gives Weld County enrollment information for 1972 for each school district. Note that 1 ) the totals for school districts given in the two tables are not equal since school children cross county lines and that 2) school districts are not coterminous with other political subdivisions. 10 Narrows Unit, III , 127. 11 Greeley Human Resources Report. 12 Abt Associated, Inc. , Draft Social Assessment of the Proposed Narrows Unit and Alternatives Thereto (Cambridge 1974) as cited in Narrows Unit. -22- TABLE II-6 WELD COUNTY INCOME STATUS 1969 All Families 22,097 Less than $1 ,000 715 $1 ,000 to $1 ,999 710 $2,000 to $2,999 1 ,210 $3,000 to $3,999 1 ,424 $4,000 to $4,999 1 ,556 $5,000 to $5,999 1 ,639 $6,000 to $6,999 1 ,570 $7,000 to $7,999 1 ,589 $8,000 to $8,999 1 ,753 $9,000 to $9,999 1 ,549 $10,000 to $11 ,999 2,809 $12,000 to $14,999 2,645 $15,000 to $24,999 2,257 $25,000 to $49,999 553 $50,000 or more 118 Median Income $8,363 Mean Income $9,361 Per Capita Income of Persons $2,616 Source: U.S. Bureau of the Census. 1972. U. S. Census of Population, 1970. General Social and Economic Characteristics, Colorado. U. S. GPO, PC(1 )-C7-COLO. , Washington, D.C. -23- TABLE II-7 ESTIMATED HOUSING STARTS, COLORADO REGIONS AND COUNTIES, 1969-1976 COUNTIES 1976* 1975 1974 1973 1972 1971 1970 1969 WELD 1 ,202 1 ,011 1 ,345 1 ,421 2,132 2,251 1 ,093 583 Single 868 903 927 985 966 766 584 433 Duplex 20 14 18 50 70 40 36 22 Multiple 314 94 400 386 1 ,096 1 ,445 473 128 MORGAN 188 82 253 118 91 32 22 100 Single 140 64 117 116 57 32 22 12 Duplex 0 2 0 2 2 0 0 2 Multiple 48 16 136 0 32 0 0 86 ADAMS 1 ,728 1 ,199 1 ,709 4,845 5,957 4,070 3,216 1 ,675 Single 1 ,673 1 ,146 853 1 ,558 1 ,663 1 ,498 1 ,610 869 Duplex 42 42 48 212 206 76 44 18 Multiple 13 11 808 3,075 4,088 2,496 1 ,562 788 * Preliminary Sources: Division of Housing estimates based on information obtained from the Demographic Section of the State Division of Planning; U.S. Bureau of the Census, Construction Statistics Division; McGraw-Hill publication, the Daily Journal ; Home Builders Association of Metropolitan Denver publication, the Metropolitan Denver Home Builder; Region VIII office of the U.S. Department of Housing and Urban Development; state office of the Farmers Home Administration; Division of Housing records ; and numerous local building departments and local municipal and county officials. -24- TABLE II-8 ESTIMATED YEAR-ROUND HOUSING INVENTORY , BY TENURE, COLORADO COUNTIES, APRIL 1 , 1970, AND JANUARY 1 , 1977 Estimated Year-Round Year-Round Housing Inventory Housing Inventory . January 1 , 1977 April 1 , 1970 Counties Total* Mobile Homes Total* Mobile Homes WELD 39,778 4,850 28,011 2,133 Owner 25,153 4,120 17,220 1 ,782 Rental 14,625 730 10,791 351 MORGAN 8,074 1 ,090 6,776 277 Owner 5,299 930 4,194 235 Rental 2,775 160 2,582 42 ADAMS 78,874 9,880 51 ,418 3,314 Owner 54,493 8,990 38,358 3 ,025 Rental 24,381 890 13,060 289 *"Owner" units include owner-occupied year-round housing units, vacant year- round units offered for sale only, and vacant year-round units rented or sold and awaiting occupancy, held for occasional use, or not otherwise classified. "Rental " units include renter-occupied year-round units and vacant year-round units offered for rent. Sources: U.S. Bureau of the Census, Census of Housing: 1970, Table 3; and Division estimates . -25- TABLE II-9 PERSONS 3-34 YEARS OLD ENROLLED IN SCHOOL BY LEVEL, 1970 WELD MORGAN ADAMS* Nursery School 511 19 N/A Kindergarten 1 ,591 386 N/A Elementary (1 -8 Yrs. ) 14,818 3,728 30,072 (K-6 grade) High School (1 -4 Yrs. ) 6,520 1 ,741 22,162 (8-12 grades) College 8,476 86 N/A Total Enrolled 31 ,916 5,960 52,234 Source: 1970 Census Data. *Source: 1970 Pupil Membership and Related Information, Colorado Department of Education Statistical Division) -26- TABLE II-10 WELD COUNTY - SELECTED EDUCATIONAL INFORMATION, 1972 County Courses Projected District Grade Fall 1972 Pupil/Teacher Ratio Offered Dropout Rate (8) School Span Membership Fall 1971-Fall 1972 Fall 1972 1970-71 1971-72 Re-1 GILCREST Valley Sr. High 9-12 485 19.2 20.2 127 19.8 11.2 North Valley Middle 6-8 191 31.8 27 0.0 2.2 South Valley Middle 6-8 228 17.5 12 0.0 0.0 Gilcrest Elementary K-4 122 21.3 27.1 La Salle Elementary K-5 355 28.0 29.6 Platteville Elementary K-5 305 37.1 33.9 District Total 1,686 22.0 22.6 20.5 12.0 Re-2 EATON Eaton Sr. High 9-12 347 20.9 20.4 -64.25 7.2 8.5 Eaton Jr. High 6-8 289 28.2 32.1 31 2.1 1.1 Eaton Elementary K-5 474 26.1 26.3 Galeton Elementary K-6 160 22.1 22.9 District Total 1,270 21.4 21.2 9.1 9.5 Re-3 (J) KEENESBURG-HUDSON Weld Central Jr. Sr. High 7-12 729 20.8 21.4 84 17.9 18.7 Hudson Elementary K-6 528 24.4 25.1 *Keenesburg Elementary K-6 153 29.4 30.6 Prospect Valley Elementary K-6 179 43.2 29.8 District Total 1,589 23.3 23.4 17.9 18.7 Re-4 WINDSOR Windsor Jr. Sr. High 7-12 511 18.5 17.9 97 10.2 18.7 Park Elementary 4-6 236 23.5 21.5 Tozer Elementary K-3 336 25.6 26.9 District Total 1,083 21.1 20.4 10.2 18.7 RE-5 (J) MILLIKEN Roosevelt 4 Year High 9-12 272 15.6 14.7 87 5.7 6.9 Letford Elementary K-4 442 33.3 40.9 Milliken Middle Elementary 5-8 356 26.8 26.6 0.0 2.4 District Total 1,070 21.0 22.9 5.7 9.1 Source: Colorado Department of Education. 1973. Consolidated Report on Elementary and Secondary Education in Colorado, 1973. Denver, CO. -27- In addition to the schools listed in Table II-10 by school district, there are several advanced educational institutions in Weld County and neighboring Morgan County. The University of Northern Colorado is general and advanced degrees. Aims Community College offers 2-year degrees and training in vocational opportunities. Another junior college is located in Fort Morgan. Private and parochial schools have a minor role in this area. A few students figm Fort Morgan and Platte Valley School Districts attend these schools. 7. Community Services a. Welfare and Public Assistance The welfare and public assistance sector includes public programs mandated by legislation and private assistance. The three county area has many such programs available; these include old age pension, aid to dependent children, aid to the blind, treatment assistance, general assistance, aid to the needy and disabled. Many people are eligible and receive benefits from these programs at the present time. For example, in Morgan County during January of 1976, there were 537 cases of old age assistance. b. Social Services and Religion There is local interest and initiative throughout the valley area in providing services which contribute to individual growth, development of health, inter-personal relations, respect and devotion to community values, and a sense of pride in and identification with the community. Residents both within and outside the area benefit from the presence of various church groups, 4-H clubs, scout troops, hobby and fraternal groups, extension clubs, and agricultural services. Additional special - ized professional services are also available or can be obtained in Denver when the need arises . Religion plays an active role in the lives of people throughout these areas. Many varied types of churches and church-oriented activi- ties exist. c. Governmental Operations and Services The area contains many local , private, and municipal government operations and services such as fire and police protection, electric supply, gas, water, and sewer. Adequate facilities are presently available for satisfying the immediate energy needs of the area. Greeley and Fort Moran have municipal systems, and Rural Electric Administration (REA) systems serve the rural sectors. Pipelines installed by private companies serve all 13 Narrows Unit, III , 121 . -28- the principal towns with natural gas. In addition, an interstate pipe- line system for transporting refined products of local plants is located in the area. Police and fire departments are located in the bigger cities and towns such as Greeley and Fort Morgan. According to Weld County Fact Book published by the Greeley Chamber of Commerce and information received from the Colorado Division of Commerce and Development, there are 67 people in the police department in Greeley and 25 in Fort Morgan. Rural areas such as Prospect Valley receive service from county sheriff departments, state police, and volunteer and rural fire departments. d. Health Health care for the area can be classified as above average. The medical community is progressive, active, and growing in number of health professionals, diversity of medical services, and facilities for health care. At the present time the area between Greeley and Sterling is ser- viced by more than 125 physicians and surgeons as well as by a number of hospitals and clinics. There are two major medical facilities in Greeley: Weld County General Hospital with 244 beds and Greeley Memorial Hospital with 28 beds. More physicians work out of both hospitals. In addition, there are a number of nursing homes in the area. Most of the medical facilities are located in the western part of the valley in Greeley, but there are more than a dozen physicians in the Fort Morgan-Brush area as well as a limited number of hospital beds including the Fort Morgan Community Hospital . Larger medical facilities are located in Denver within a short driving distance. Health problems of special concern in this area include strep- tococcus infections, cancer among the elderly, and preventive health care among the rurally-isolated and the migrant workers. -29- C. Land Use 1 . General Land use refers to the kind of activity for which any given parcel of land is being utilized. Since present land use conditions and activi- ties exert such a strong influence on the type and extent of future development, it is necessary to recognize existing land usage as an important factor in the planning process. The Weld County Future Land Use Map (Map #4) shows existing develop- ment areas in Weld County as well as growth areas for future development. Lands administered by the Federal government total 211 ,343 acres. Refer to Table II-11 . State controlled lands amount to 168,152 acres, and there are approximately 8,973 acres in the County and Municipal category. As shown on the Weld County General Soil Map (Map #5) , the largest percentage of irrigable land is located in the vicinity of the South Platte and the Cache La Poudre River valley floodplains and their main tributaries. Most of the grassland areas are located in the north portion of Weld County. The greatest percentage of the county is dry- land and rangeland. Sage and brushland areas occur in the south part. The economy of the project development and service area is based primarily on agriculture and agriculturally-associated industries. Most of the land with suitable soils and the river valley and surrounding uplands are intensively farmed, under irrigation, with corn, sugar beets, and alfalfa being primary crops. Sprinkler irrigation is a recent innovation introduced within the last 15 years in this area. Much of the corn and alfalfa is harvested to provide grain or silage for use on the farms or for sale to nearby liverstock operations, such as the Monfort feedlot near Kersey. The only crop of economic significance grown without irrigation is winter wheat. Lands of the river valley which are not well suited for irrigation or dryland farming due to deficiencies in soils (very sandy or gravelly), topography (steep terrace breaks, low-lying river bottoms), or drainage (high ground water or lack of surface drainage outlets) are generally left uncultivated. These lands are used for pasture and provide supplemental food for livestock. The local livestock industry consists primarily of calf production, sold locally to feeders for finishing and slaughter. There are two large feedlots presently operating near the develop- ment area. Webster feedlot is located about 4.5 miles east of Greeley, and the Monfort feedlot is located about 2 miles east of Kersey. Poultry is raised in the city of Hudson, which is located in Weld County 23 miles south of Greeley. Although there are a number of poultry and pork producing operations in the area, they are of relatively minor economic importance to the region. -30- L t C 1 WELD COUNTY „ -4— ,�` Y E'p t� � f l;— f' FUTURE LAND USE MAP ` ".. �� I .,,,, _ ' .1 _ ;a _ I ,A' BY TW COUNTY PLANNING .'.' i "1 3- 4--7 i-- - 1 T-- -- - OFFICE r`` ,.1 4. } yy,�� ) {{ T .' \ JANUARY 1973 T {' -{'.- -. i"•r " ._ 15 T f. _ l#.- T G y V EXISTING URBAN DEVELOPMENT 1 Iv '- IL + . FUTURE TOWN GROWTH AREAS = � 41',,,,,1N., -°''''' T —„S' ' �'1i aI- �' FLOOD PLAINS & MAJOR RESERVOIRS t N.-1,5&,11...: �A .1' _ � • ' �_ F FLOOD PLAINS IN TOWN GROWTH AREAS ® y ,,,,.....\ r _ { '' 111 FLOOD PLAINS IN URBANIZED AREAS ^'� - i- tF" 'I 1 I_Y J- -1- - px-i i•/ , , :TRANSPORTATION LEGEND V 1-'1 A}} 1 • ''1 1` „. 1 • -- FREEWAYS t { "'� I F = -->- . � EXISTING -•� j v S�` i- �I �-_ ..1 Y ♦ - - - PROPOSED 'N 1� • I lY (I - EXPRESSWAYS EXISTING .o 'j\ 1 -. '1 1 L f }i � ` {{ 1 }_ i 1111 PROPOSED { r c, s. t "j -t {�.) ,yy�,,, ARTERIALS � •-ter � � E°'`}(—�' _ j i� --*_ c E�w EXISTING `/, �i .......... - PROPOSED —'—'—'------- - l a.. r •. .` _ r ;t-' Notes — f T -� 1••.. < ". *ti ; Grover Keota and Roemer not •` �= • r' shown this map F specific _ r:Information concerning For towns si hr to tM Waltl Cou tY Plannln •• / « r OffCe the r•ip tiw to couRclk Y�Ilse y }_ y For tleteded Wntl use within urban T4!' ive - `..=_=pptoO.O ' ��.,.�•, Lucerne GIII antl G•1•ton are r iM IF,.I�EE,,`b,` _. --1-0-•{ • i 43 r{ unlncorPoretetl arses ^ '. ��i 9lFl�r��t N q f WC LE \ � MILES _.,gyp;iu�, •' 1- ILrL-SALLE 1 S 7 1 7lanL�. -0 x .Emil d Q�1 js , ti- ?n t t - 1' a L h - -.a+1--Y-' a l -a �lAr E '� It ► - � ,,- � rt , .,. •At, IRE E - ] } 1 _ — i -.-.. I p [��{, } r T ► p w; � _ 1 ,l_ ' -t r ,•F :j- ;!� 1 �„ le -. _ y_.. 1 3 _ y - 1 M THIS MAP IS INTENDED FOR GENERAL ' t L -�fv �. rl s , I�FL .W -- PLANNING. 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V TABLE II-11 COUNTY AREA, INCOME SOURCE, AND LAND OWNERSHIP PROJECT AREA County Area Major Land ownership (acres) (square Income County & County miles) Source Private Federal1/ State Municipal Weld 4,004 agriculture 1 ,706,573 211 ,343 168,152 8,973 industry Morgan 1 ,282 agriculture 706,816 2 ,459 54,161 2,750 Adams 1 ,240 agriculture 772,180 17,920 1 ,003 2,497 industry Logan 1 ,827 agriculture 1 ,011 ,569 1 ,612 135,790 768 Washington 2,525 agriculture 1 ,493,100 795 106,530 27,995 Sedgwick 544 agriculture 309,751 273 6,108 56 Source: Colorado Interstate Gas Company, 1972 Colorado Marketing Manual 1/ Federal lands are based on the Pawnee National Grassland area of 193,000 acres in Weld County and the areas of Bureau of Land Management lands -35- 2. Projected Land Use The amount of idle land and land used for agriculture in Weld County has decreased in recent years due to urban development. For this reason and because an increased percentage of urban population and industrial growth is projected, an appreciable change in overall land patterns around the urban areas in the west part of the county is fore- seen for the period of this study. The projections for future land use needs are based upon the popu- lation projections for urban communities in Weld County shown in Table II-12. The following standards for estimating future land use demands were utilized: Residential - 10 acres for each additional 100 persons. Commerical - 0.8 acres for each additional 100 persons. Industrial - 2 acres for each additional 100 persons. Public/Semi-Public - 3 acres for each additional 100 persons. Table II-12 shows the communities which are projected to experience population growth throughout the planning period as well as an estimated number of acres which will be needed to serve their added populations. This data is the basis for projecting water and sewer needs on the Water and Sewer Facility Plan maps. Residential growth areaslr4oincide with future water and sewer service areas for 1980 and 1990. There will also be a considerable amount of "filling in" type residential growth. It is recommended that vacant parcels be developed before new land is annexed into the communities, since the parcels are in most cases already served with water and sewer facilities. Future commercial development, in most instances, should occur contigous to existing business areas or in vacant commercial structures through redevelopment. Also vacant parcels in commercial areas should be developed in order to make a more compact downtown area. Future industrial development would be best located in existing industrial areas ; in no case should industry be allowed to develop in residential areas. 3. Transportation a. Highways Vehicular traffic is increasing on the major thoroughfares in Weld County. The safe and efficient movement of this vehicular traffic is necessary both for the safety of the people of the county as well as the economic health of the areas. In the past, consumer incomes have been rising, permitting increased vehicle ownership. This in turn has 14 Water and Sewer Facility Plan for Weld County, Colorado, Report by the Colorado Division of Planning (Denver 1972). -36- cn N E "0 "Cl z 3 r 3 7C C-, 7C = -n G) j c) m -n m m o D C) O C 11 CD CD 0 cD a O Z �• < Z Z 11 G) CO C -1 J -I = CD CO = N co CD S 9 C. •T O -S --J Cu co --h Cr n 3 9 r •S d T C+ 7 O1 0. 7 7 N N C+ < CD n 7 0- MO 0 C+ 3 n (tam N f) C+ cD N cD 0 CD N Z N cD = 7 C CD CD 0 CD CD 7r -1 N C+ (< = r 9 Cr cD J 0 7 .. 0) -0 9 < CD CD D- 0 C 0 N • n o O = C `L -0 = Cr n t G -s y1-0 Z 7 Cr I'D 7r o CD C 1/40 0 a Cr -+ (D tit 00) CD rr to toCO 0 C cD Z 7 Z N AI N N CO .-1 O I N 7 . V 7 -17 J OCa)A a CO N V -N CO N) N) O a CO _ 0l I n J V) 7 7 ct CO a CO 03 V N O N CO CO CO CO 0 a CT 2• Jtt] al OD V W CO 01 CO tp at N tp O CO O A V O 1/40 1/40 [L Cr > cam N -. 0 =3 CL CD O fD O W ID T 01 = m o o Z r-I Z P) C .CD I--4 v 7 • 3 I o n 0) to N _ N N N) N) N CT to .-"00 N 0) .l1 7 C+ 0 O A O1 N in O A 01 0 N) 0 W CO O 0 CO CT O1 N 0 C • Z 7 0 0 0 0 O T 00000001010000 0 0 0 N 0 O O O O 0 O O 1 0 in O 0 O 0 0 O O O 0 O 0 0 O O O O O O 0 0 O -' CD PI = O C N t0 N �• V Cr 3 0 as o m ( ) SD = -4 O 0 --.• m 7 n C N cD C co a N O C1 0 S = N C O -J 0 J N) CO N)Cu 01 �• O 7 7 C+ n A A CO N N) V CO N A 0 A A A CO A J1 01 011 d h-I Cr N0 CO A A CO ICI V (.31 V V 0 N) CO N W CO O CT CT ID O -0 Cr) 03 V CO W 01 () LO 0) N t0 0 W O A V O tO C 0 0) a = I r -° tC CD r r Cu O_ z 7 cr o 0 0 0 C) C 7 N I VI • CD � m C C N) - CON W N< 7 CO a O) a 01 N CO N t0 CO V CO CO N CoW N T z o CD • • CD rr CT a O1 CO a N A a CT N t0 O A W a A COW lO CT m N as - N Cu 0 t0 0 N 7 7" 1 E w n CD 7 cL CD I-• t0 O ID CD 7 t0 ID C1 0 O1/40 O C < O Co A W 01 N) N CO A C) A W Cu N CD t< 0`O• CO al A Cr, O1 co 01 O 1/40 O N CO Co CO O) 03 N) N) t+ a • _ o O V 0 CO 01 0 CT CT N CT 01 N O1 01 Co 01 —+ Co N CO N -' -0 C+ al 3 et CD 0. 7 rr el- t• 0 _ Cr N CD t0 0) E 'Q V G+ �. C •• Cr A CI I Cr 01 COA 61 COCOO A COA O W N N CO V) N CO CO 01 -_+ C -1. N -✓ A CT ♦O 1/40 N V N CO CO 01 CO t0 1/40 CT N -r 01 W N CO C^ O CD a. n C C Z N) D a 7 N 01 CO O1 CO N O N 00 C.0 A N) CO N a 01 CO CO N CO 01 0 0 A CI CO CO 0 0 01 A A 010101T A A Cr C+ CO • CO • CO O t0• • CO N) a CO O W • N A CT a t0 • N CU S CD l0 Q1 O a � N CT A t0 � N V A COlD COW N O CO (Tl � A -37- influenced to a great degree the increase in vehicular travel in the county. With more vehicular movements it becomes important to maintain efficient traffic systems in order to reduce traffic accidents and vehicular congestion . In Weld County the largest traffic generator is the City of Greeley. Other traffic generators are the smaller communities, Empire and Riverside Reservoirs with their accompanying recreation areas, and the scenic areas in the Pawnee National Grasslands. If the free and easy movement of people and goods can be accomplished expeditiously on strategic roads, the Weld County transportation system should function safely and efficiently. The existing federal and state highways serve as the major road system, providing main access from the outlying regions for out-of- county and out-of-state visitors. The county road system in turn pro- vides general area access. County roads falling mainly within the Federal Aid Secondary (FAS) system serve as the chief access links between communities and the federal and/or state highways. Minor county roads in turn serve individual areas and link certain communities. Major highways serving Weld County include I-25/U.S.87, I- 76/U.S.6, U.S. Routes 85 and 34, Colorado State Routes 14, 52, 66, 257 and 392 and a segment of Colorado State Route 79 in the southeast corner of the county. Interstate Highway 76 extends from Denver through Fort Morgan. The highway bisects the three county region providing a major east-west transportation route. Interstate Highway 25 lies on the western edge of Weld and Adams Counties and provides a major north-south route. Refer to Map #6. Traffic volumes on the major routes in Weld County,ltre summarized below and expressed as annual average daily trips (ADT). The highest average daily traffic volumes occurred on I-25/U.S. Route 87 at the south edge of the county. Average daily traffic trip totals amounted to 17,300 at this point. Approximately 12,900 average daily trips were counted on U.S. 85 at a point at the south edge of Greeley. At the point of departure of I-25/U.S.87 at the north edge of Weld County, 12,450 average daily trips were counted, indicating that this traffic facility carries high volumes of through traffic. In the Keenesburg area 5,200 ADT's were counted on I-76/U.S. Route. Average daily trip totals on Colorado State Route 14 amounted to approximately 2,550 ADT's at a point west of the C-257 junction, and approximately 2,450 ADT's were counted on C-52 west of the town of Fort Lupton. County roads provide access from farms, ranches, and residences to major highways. Large portions of these roads are unpaved and surfaced with gravel . The access road to the mine site will follow presently constructed county roads for several miles. New access roads will be constructed after leaving the county road. 15 1970 Traffic Volume Map, Colorado State Department of Highways. -38- I r ' . . ! • "� I 3 �. ® r. • " � 4 i•, C7 ;, \� I , x /.E.x s A. rs •i.- „ t i p i I z • I �. `` I (-I 4 i '• 4. t I •I `< 8 x JI rt t• We • I R s l I u3 I f LC . — •1\-\ •• � I = I< t1 I i I a ; 3 • � _ r I z1 �:•• qj . I i - Z 1 „1- r • I—--- b! ✓ --._; . ; - - - _ i I !�. ° It z • I • I •I t->tsrrf,a.3�w ! I I x } . I 11 ` __ •01 3 ! j �•'' ! i i i , I 71:111 ..... je" / 1 . A 9 I i-il ,:z. - I \I I ' ' . s . 2 t c .0 • i I 3 •a • IQ SCALE OF u S-f NORTHEAST COLORA 1 (Showing Mine Site - Enlarged for clarity) b. Railroads The Counties of Adams, Weld, Morgan, Sedgwick, Phillips, Washington and Logan, as shown in Map #7, are serviced by the Union Pacific and Burlington Northern Railroads. The Union Pacific serves the western portion of Weld and Adams Counties with a line running from Cheyenne, Wyoming, to Greeley and Denver, Colorado. Burlington Northern lines dissect the seven-county area and service the cities of Fort Morgan, Brush, Keenesburg, Roggen and Hudson. Both railroad companies serve the large as well as the small communities along their respective routes and provide sidetracks for loading agricultural commodities. Area manufac- turing and agricultural products are easily transported through the state and county. Passenger service is provided by AMTRAK, which uses the Burlington Northern line from Denver to Fort Morgan and Akron. Passenger service is not available to the cities of Brush, Keenesburg or Roggen. The Union Pacific, Denver and Rio Grande Western, and Burlington (CB&Q) Railroads serve the communities in Weld County. All provide service to and from Greeley. The CB&Q Railroad serves the northeast and south- east areas. The Denver and Rio Grande Western maintains a short length of trackage in the extreme west portion of the county. The Union Pacific provides service north to the Cheyenne area and east to Fort Morgan. In summary, most of the communities in Weld County are presently served by rail facilities. Although passenger services have been dis- continued, the railroads continue to play an extremely important role in the Weld County transportation network. c. Airports The utilization of aircraft for business, industry and personal pleasure is an important activity. Planning for aviation needs involves an analysis and understanding of current activities, Federal and State legislation, and agency policies affecting air transportation and fore- casting. Navigational aids and ground support systems are required in varying degrees at all airports. The needs for the various services depend on the transportation mission of the particular airport. Minimum service and support facilities are recommended at all public airports regardless of size. These include: 1) Public telephone 2) Suitable access road 3) Terminal or operation building 4) Hangars for based aircraft and hangar space and/or tie-downs for transient aircraft 5) Fire protection and police security patrols 6) Fueling service 7) Attendant (at least part-time) There are three public airports in Weld County: the Weld County Municipal Airport at Greeley, Easton Valley View and Flying "D" Airports. -41- I TSP-5 7,: P 3 kl21) i 1 .:X.,,‘-'' E.; ?"```.\/-1 .. - ..1 n ). .ca...1- :. ' 3., .'.,It..,-; : i: ,it ' 1. / ‘2.- . f• c: , c \-1 F',!? ' - u 1 4:4 i 21:',V4:41/ "i}.3Cf:::' i 3 V: 1 'F. % 1:-• ' "C./C.;; i 63 ' a: C-; Pr I 2'-- ill ll �' J, em `4.-l y�".O 'i.+ off; 1:11.11:71: .r < i,L�.,r:y. - v [ue se so . ,5 s +� 1 -o! �\ ,a '.. IN -7-4.^—if-,11, '°ro °nY o I ,t,, x It = 1 1 Z]s\71 E'1yd l'4:::::71:e1:5-77 E _ JE 1 t4YO + �� n Y,,v'ir e rn J. , e o - ; c o y ., ./` /te.•. 'Ip .1., s.,5: c4eo - eJ . V ac a .t•`'v A > ,B r rY O J a 9 y J? _ ec '-LS;: .YOB'..._-t � =-= "" ¢ i i o ; • EU ••,, VIA •I"CIL. _ 30 _ F 1 a _ P....; U y • e I O W E O . rt in 'J,o: _ _ EI�® E_ _ ," ��U � O o / ' ® Ia _ I . J �' o r .0`�t' d' - e W } _ d, I Z le a N p ..r^•d st.. I 2 1 by ,.'o •�e e W Z u c `J.`'s ,: U. o. - CC OW W 2 Z z P. • •‘9:0‘*r0..t }��a �-- �.� �.�..°." �--- 3 1...c 4 1 !j O. - •? + * E 00 o e °- •Y`s. '. 1 i! t� -k W ZZZmcaftb IL 1 ID („Dococr<cccrLLEL EC. o + • a •y`. e , i! i! S'jolt U Z Q 2¢W o ee Z 1 E o'•Je J• _ ' . .iE _i J2000W-QZZ _ , • i ,n •14 gran ' LU OOC2NJ I /�/ ` !E•_ c r,'ryJ . 'J >, m=mN32 `6 of i .i.LfN o .',,,. . .�,-;7 r uyt3 t g 00006000SLLD 1 ~u ur••'•• • c' 1, c 000000NJ I up Of',12117-24.4, i •V Y 0__ , . ,, y y •3 § Main, i 1 y 1:` `' E U 1`%.`' ' u--. • e V I U`� ou `._I V u 'll ,. E �JE 0 j � c t= =aN , A__ aI 00 a _d2- There are also seven small private airports. According to the Colorado State Airport Plan there is one new public heliport proposed for Weld County in the Greeley area. A comprehensive statewide airport systems plan in preparation at the present time could indicate additional needs for the county. Commercial airline services are available in Denver, Cheyenne, Wyoming, and Sidney, Nebraska, and are within a few hours' driving time from any area within the three-county region. Numerous smaller air- ports, airstrips, and landing fields are located throughout the region. None of the population centers near the project site have commercial air service. The local airport facilities provide services for both private and commercial light aircraft transportation. d. Commercial Bus Service Two commerical bus lines operate in the Weld County area. Conti- nental Trailways provides service on a regular basis to the communities along I-25/U.S. 87 and I-76/U.S. 6. The Greyhound Lines provide service to the communities along U.S. Route 85. In light of the fact that rail passenger service is no longer available, commerical bus passenger service in one form or another has taken on added importance, and it would be desirable to provide this service to the communities in Weld County which are not served at the present time. e. Utilities In the project and service area, facilities are presently available for satisfying the immediate energy needs of the area. The proposed mining area is served with electrical energy from Home Light and Power Company of Greeley. Fort Morgan and Julesburg have municipal systems, and the Rural Electric Association (REA) systems serve the rural sectors as well as Keenesburg, Kersey and Roggen. Private companies serve all the principal towns with natural gas. f. Communications The area has mass communications including newspapers, telephone, radio, television, libraries, magazines, etc. Denver provides two large daily newspapers and television from the national networks. Greeley has a number of newspapers and radio stations. Fort Morgan has two radio stations, and Sterling has one radio station and a TV- station. News- papers are published in Fort Morgan, Brush, and Sterling. Libraries are located in Fort Morgan, Brush, Sterling and Greeley. g. Pipelines Two gas pipelines (one interstate and one intrastate) run through the area. The first is owned by Phillips Petroleum which gathers crude products from local wells and pumping stations. The pipeline is pro- posed to be moved as part of the Keenesburg mine project because it lies within the project's right-of-way boundary. The second pipeline is owned and operated by Coors Industries and supplies gas from the Wattenberg gas field to Coors in Golden. -43- 4. Recreation The Keenesburg mine site is within the Colorado Division of Parks and Outdoor Recreation designated Planning Region #2 which encompasses Larimer and Weld Counties. These counties presently (1977) have recrea- tional areas and parks under development. Most are general improvements to existing facilities around the larger metropolitan areas. No further developments are planned for the immediate future. Weld County has no plans for development of recreational sites in the area near the Keenesburg mine project. However, many recreational service areas are located in nearby Planning Region #1 , which consists of Morgan, Logan, Washington, Sedgwick, Phillips and Yuma Counties. a. Area Recreation Availability Region #1 has 292 recreation areas with 45,047 acres available for recreation. This represents less than 1 percent of the recreation acreage available in Colorado. Based on the Bureau of Outdoor Recreation's recreation land classifi- cations, the 292 recreation areas in Region #1 are categorized below: Number of CLASSIFICATION AREAS TOTAL ACREAGE I High density recreation 263 14,010 II General outdoor recreation 12 20,978 III Natural environment areas 17 10,059 IV Outstanding natural areas - - V Primitive areas - - VI Historic and cultural sites - - Region #1 has 8 percent (or 3,657 surface acres) of Colorado's total water surface area provided by lakes and reservoirs available for recreation. The region also has a little more than 1 percent (9 miles) of Colorado's river and stream mileage and 10 percent (11 ,271 miles) of Colorado's road and trail mileage. Supply-demand analysis16 indicates Region #1 has needs for areas and facilities for the following recreation activities : 1 ) Hiking trails 2) Hiking, walking on roads, sidewalks 16 Interim Colorado Comprehensive Outdoor Recreation Plan, Colorado Division of Parks and Outdoor Recreation. -44- 3) Bicycling across open country 4) Bicycling on roads 5) Motorcycling on roads 6) Open space motorcycling and four-wheel driving 7) Four-wheel drive on regular roads 8) Lake swimming 9) Stream swimming 10) Tennis 11) Golf 12) Sledding/tobogganing/tubing 13) Lake/stream ice skating 14) Rink ice skating 15) Stream fishing 16) Hunting Table II-13 shows the total number of recreation areas, relative percentage of those areas in the state, the total area in acreage, mileage, and square feet for the listed recreation categories, and each area 's percentage of total state area. This table summarizes the recrea- tion resource "supply" or relative recreation opportunities available for resident and nonresident visitors in Region #1 . Region #3, consisting of Adams, Denver, Arapahoe, Douglas, Gilpin, Clear Creek, Jefferson, and Boulder Counties, is adjacent to the south- west portion of Region #1 . It includes the Denver metropolitan area (which generates a substantial recreation demand) and the Central Colorado Water Conservancy District. Region #3 needs for recreation acitivity areas and facilities are as follows : A) Most significant needs 1 ) Stream swimming 2) Group camping 3) Water skiing 4) Stream canoeing 5) Tennis 6) Miniature golf 7) Downhill skiing 8) Sledding/tobogganing 9) Ice skating on rinks 10) Hunting B) Other needs 1 ) Open space motorcycling and four-wheeling 2) Pool swimming 3) Picnicking in picnic areas 4) Camping in campgrounds 5) Water skiing -45- TABLE II-13 LOCAL RECREATIONAL ACTIVITIES NUMBER OF TOTAL ACTIVITY AREAS PERCENT2/ ACREAGE PERCENT2/ Playground: Field Games 129 9 269.5 6 Appartus 83 6 23.9 0 Open Space: Camping 34 3 11,082.9 0 Picnicking 74 7 25,955.9 0 Summer vehicle use 2 3 17.0 0 Bicycling 16 14 41.5 0 Horseback riding 23 4 14,253.9 0 Hiking and Walking 72 7 27,618.6 0 Mountain climbing -- -- -- -- Play area 136 10- 10,580.9 16 Bird & wildlife obser- vation & photography 30 5 27,976.4 0 Rock hunting 1 0 4,050.0 0 Trap & target shooting 4 4 57.4 0 Winter vehicle 1 1 2.0 0 Sledding, tobogganing tubing -_ -- -- __ Skiing and snowshoeing -- -- -- -- Lake, reservoir: Fast boating 3 3 3,657.6 8 Water skiing 4 5 8,050.0 19 Sailboating 3 4 7,180.0 21 Slow boating 8 3 8,796.6 13 Ice skating 2 2 6.0 0 Ice fishing 7 2 8,041.0 23 Ice vehicle -- -- -- -- Other winter activities -- -- -- -- Lake swimming 7 5 0.9 0 Shore fishing 17 2 33.1 1 River Stream: Total Miles Canoeing & Rafting 1 1 0.5 0 Power boating -- -- -- -- Swimming -- -- -- -- Tubing 1 1 3.0 1 Ice skating -- -- -- -- Ice fishing -- -- -- -- Fishing 6 1 9.0 0 . Road, trail : Two-wheel drive 21 5 11,271.2 15 Four-wheel drive 4 -2 11,299.1 18 Motorcycling 3 1 10.1 0 Bicycling 3 3 8.3 1 Horseback riding 7 1 30.5 0 Foot trails 6 1 6.7 0 Snowmobiling -- -- -- __ Sledding & Tobagganing -- -- -- -- Skiing, Snowshoeing -- -- -- -- Total Acreage Zoo -- -- -- -- Historic site 1 1 240.0 0 Cultural site 15 8 506.3 0 Natural site -- -- -- -- Overlook -- -- -_ Swimming pools 21 3 65,3403/ 4 Ice rinks 4 11 39,204 / 5 1/ Based on the Colorado Division of Parks and Outdoor Recreation's Interim Colorado Comprehensive Outdoor Recreation Plan, which describes Planning Region 1 to include the counties of Morgan, Logan, Sedgwick, Phillips, Yuma, and Washington. The planning region approach did not provide statistics for each county; therefore, the statistics for counties outside of the project development and service areas could not be separated. 2/ Percentage of total areas and acreage in Colorado. 3/ Square feet. -46- b. Hunting Pressure i . Migratory Birds17 a. Ducks The South Platte Valley is the most important duck harvest area in Colorado. This is to be expected, since this region supports more wintecgng ducks than any other area of the state. An average of 83,125 ducks is harvested annually in the South Platte Valley. The harvest comes from Adams, Logan, Morgan, Sedgwick, Washington, and Weld Counties. This harvest amounts to about 40 percent of the state total . Mallards make up 90 percent or more of the total bag of ducks. The average number of duck hunters is about 11 ,900* each year. Ducks are hunted around lakes and reservoirs and on open ponds and marshes, but most of the harvest occurs in the river bottom lands during stormy weather. Table II-14 shows hunter use in the South Platte Valley and the contribution that the area makes toward the total migratory bird har- vest. Duck harvest in Region #1 averages about 9,900* annually or almost 12 percent of the total South Platte Valley kill . An estimated 1 ,389* duck hunters visit the area each year. This number represents 11 .6 percent of the South Platte Valley total . Hunters harvest most ducks along the river channel and from warm water sloughs and seep ditches in the river bottom. Field and reservoir hunting is limited (except on stormy days) because the ducks leave the reservoirs, feed in the fields, and return to the reservoirs again after legal shooting hours. It is estimated that 75 to 80 percent or more of the river bottom land is leased for hunting by private individuals and clubs, and these small groups account for a large percentage of the duck harvest in the area. Some river bottom landowners allow public hunting, but hunting in these areas is usually of lower quality than in leased areas. The general public finds most of its hunting in fields and around the shore of Jackson Reservoir. For these reasons private lessees of river bottom tracks are most likely harvesting more ducks than the general public, which makes up the bulk of the 1 ,383* duck hunters in the area. The general public is not presently realizing maximum use of a public resource; relatively few individuals are obtaining most of the benefits. 17 Richard M. Hopper, Evaluation of the Impact of the Narrows Project on Migratory Birds and Hunting Opportunities in the South Platte Valley, (Denver 1965) as cited in Narrows Unit. 18 All statistics followed by an asterisk (*) are from the Colorado Division of Wildlife letter of June 25, 1974, as cited in Narrows Unit. -47- TABLE II-14 MIGRATORY BIRD HARVEST AND HUNTER USE Type of Average Percent of Avg. Annual Percent Migratory Annual South Platte Number of South Platte Bird Harvest Valley Total Hunters Valley Total Ducks 9,871* 11 .9 1 ,383* 11 .6 Geese 370* 19.7 506* 18.6 Mourning doves 1 ,721 4.4 160 3.6 TABLE II-15 ESTIMATED UPLAND GAME HARVEST USE Average Average Annual Annual Number of Species Harvest Hunters Pheasant 561 336 Cottontail rabbit 2,266 489 Bobwhite quail 75 25 -48- b. Geese Goose harvest in the South Platte Valley is not nearly as great as that in southeastern Colorado, but the kill averages about 1 ,875* annually in the counties listed above for the duck harvest. The number of goose hunters averages about 2,720* each year. Interest in this sport appears to be increasing each year in the South Platte Valley. Harvest of geese in the Region #1 area amounts to an average of about 370* birds each year, or nearly 20 percent of the South Platte Valley total . This harvest is obtained by an average of 506* hunters. Most geese are harvested in fields and along the shore of Jackson Reservoir by experienced hunters, with only a few birds being taken in the river bottom land. For this reason the public opportunity to bag geese is greater than that for ducks. The public can generally obtain permission from landowners to hunt in fields, and most of Jackson Reservoir is open to public hunting. c. Mourning Doves Annual mourning dove harvest in the six-country area of the South Platte Valley amounts to an average of 39,000*. This kill is obtained each year by an average of 4,500* hunters. Dove hunting is largely restricted to the first week in September because cool weather generally forces the birds south. Hunting takes place near sources of water, in harvested grain fields, and on fallow cropland containing sunflowers. An average of 160 mourning dove hunters harvest a little over 1 ,700 doves* annually in the area. These figures amount to 3.6 percent of the total hunters in the South Platte Valley and 4.4 percent of the harvest. Hunting pressure and harvest are low here because doves are widespread in Colorado. The public ordinarily has little trouble getting permis- sion to hunt in places where the best hunting occurs: grain fields, fallow fields, waste areas, etc. ii . Upland Game19 a. Pheasant Based on the pheasant distribution and density classification survey made in 1957, there are approximately 320 square miles of pheasant habitat in Morgan County. Most of this lies within the South Platte Valley. According to the 1963 Colorado small game hunter harvest survey, Morgan County is credited with 5,129 pheasant hunters per year (8-year average). These hunters reportedly bagged an average of 8,561 pheasants each year. A total of 5,129 hunters equally spaced over the 320-square-mile hunting in Morgan County yields a hunter density of 16 per square mile per year. Based on the average kill of 1 .67 birds per hunter, 27 pheasants (average) are taken annually per square mile in Morgan County. Projecting 19 Hopper. -49- the pressure and kill per mile to the 21 square miles to be inundated below the top of the joint-use pool , an estimated 336 pheasant hunters use this area each year to harvest 561 pheasants. Refer to Table II-15. Hunter density is greater near the population center of Fort Morgan than on most Morgan County lands, but no allowance was made for this in the 1963 Colorado Survey computations. b. Small Game The small game hunter harvest survey indicates that 2,172 cotton- tail rabbit hunters annually harvest 10,071 rabbits in Morgan County (4-year average, 1955-1958). At least three-fourths of this rabbit hunting takes place on the river bottom land of the South Platte Valley. An estimated 489 rabbit hunters annually harvest an average of 2,266 cottontails in the South Platte River Valley. c. Quail It is difficult to compute the use of the project area by quail hunters. The Morgan County Wildlife Conservation Officer estimates that 25 quail hunters pursue their quarry in Region #1 . These hunters kill an estimated 75 birds annually. c. Fishing The Narrows Reservoir, if constructed, would support a good warm- water fishery consisting of walleye, northern pike, largemouth bass, white bass, crappies, sunfish, and catfish. Carp and other nongame fish are present in the river, and it seems likely that one of the fishery management problems would be control of these nongame fish in the reser- voir. Jackson Reservoir has potential as a high-quality walleye, pike, and bass fishery. About 5.5 miles of the South Platte River downstream of Narrows Dam would be managed as a coldwater fishery. About 1 ,700 acres will be acquired along the South Platte River downstream from the proposed Narrows Dam to help mitigate losses and damages to wildlife resource and habitat. This area, which is bisected by the river, will provide river bottom type wildlife habitat, access to the 5.5 miles of coldwater fishery to be developed by the Narrows pro- ject, and will establish public ownership and access between the reser- voir and lands presently managed for fishing and public use by the City of Fort Morgan. d. Recreation Plans The Narrows Reservoir zone of recreation influence will include an 80-mile radius from the proposed site and the adjacent cities of Denver, Fort Collins, Longmont, Loveland, and Greeley. Assuming that the popula- tion in the region will continue to increase and water-oriented recrea- tion will continue at its present popularity, it is estimated that immediately following completion of construction, the annual visitor-day use will total about 1 ,225,000. -50- The Jackson Public Use Area would include Jackson Reservoir with its 2,500-acre water surface and 780 acres that would be acquired in the fee title to water rights. Camping and picnicking facilities would be provided, and the reservoir would be maintained at about three-fourths capacity in season to provide an excellent beach for swimming. Other recreational opportunities would include sailboating , canoeing, hunting, and fishing. Water surface levels would be adjusted as required to provide the desired conditions for managing these uses. e. Possible Recreational Areas Three other nearby privately-owned irrigation reservoirs Riverside, Empire, and Bijou have potential to provide recreation opportunities, but at the present time are closed to general recreation use. There is little or no public land at these reservoirs available for recreation development, and reservoir drawdowns conflict with recreation purposes. The Morgan Game and Fish Conservation Club in cooperation with the Colorado Division of Wildlife administers the Muir Springs Recreation Area, which is located along the South Platte River just west of the City of Fort Morgan. This tree-covered area is open to public use but has very few facilities. -51- D. Archaeological and Historical Sites 1 . Regional A literature search and review of the proposed area showed no documented archaeological or historical sites on or in the immediate vicinity of the Keenesburg mine site. A further search attempted through the State of Colorado Archaeologist's Office again showed no documented evidence of any archaeological or historical sites on the proposed mine site. The following is a list of documented archaeological and historical sites near the mine site in the Weld County. Most are to the north running parallel with U.S. Highway 34 from Greeley. a. Dearfield Dearfield is located west of Fort Morgan on U.S. Highway 34 and seven-tenths of a mile west of Masters in Weld County. One of Colorado's most unusual ghost towns, this all-Negro farm colony was begun in 1910 through the inspiration of Booker T. Washington 's Up From Slavery. Dearfield was successful for a few years and grew to a population of almost 1 ,000 in 1920, but drought, lack of capital , and other factors led to its eventual abandonment. Only four or five buildings now remain. b. Dent Indian Site The Dent Indian Site is in Weld County about seven miles southwest of Greeley near the former town of Dent and about two and one-half miles southeast of Milliken. Dated around 10,000 - 8,000 B.C. , this is the first site in the United States where discoveries Clovis points and mammoths were clearly associated. Clovis points, named after a town in New Mexico near the first Clovis discovery, appear to be about 11 ,000 - 12,000 years old. This was the first site in the New World to absolutely establish the contemporaneity of man and mammoth. c. Fort Gerry Fort Gerry is in Weld County at the confluence of the South Platte River and Crow Creek. This early trading post was operated by and named for Elbridge Gerry in the 1830's. The original site was abandoned in 1840 when Gerry moved across the Platte to establish a post on the south bank. Gerry managed the post with the aid of his two Indian wives. d. Fort Latham Fort Latham is located two miles southeast of Greeley in Weld County. The site of one of the first settlements in the area, Latham was a stage station (1859-1870), a refuge for settlers against Indian raids, a training ground for the "100-day Volunteers" in 1864, and the first county seat of Weld County (1864-1970). It was named for a California senator who strongly advocated the overland stage route. -52- e. Frazier Paleo-Indian Site The Frazier Paleo-Indian Site is nine miles east of Greeley in Weld County. Dated back to 8,000 B.C. , this recently discovered Paleo-Indian site is related to the Agate Basin Complex. It was a prehistoric camping and butchering site. f. Fremont Expeditions Many of John C. Frenont's expeditions entered Colorado using the South Platte as a trail marker through Colorado. Fremont's first expedi- tion west to the central Rockies entered Colorado via the Platte and crossed four Colorado counties (Sedgwick, Logan, Morgan and Weld) follow- ing the South Platte. After visiting Fort St. Vrain, he turned northward through Weld County into Wyoming. Frenont's second expedition to California for the United States Topographical Engineers in 1843-44 crossed the Counties of Sedgwick, Logan, Morgan, Weld, Adams, Denver, Arapahoe, Douglas, Crowley, Otero, Bent, and Prowers. During his second expedition Fremont used both Thomas (Broken Hand) Fitzpatrick and Kit Carson as guides. His general route was along the South Platte to Fort St. Vrain, south to the Arkansas, back to Fort St. Vrain, and northwest out of the state via the Cache La Poudre River. Returning from California in 1844 the expedition entered Brown 's Hole in the northwestern corner of the state, followed the Little Snake River into North Park, turned southward to the headwaters of the Colorado River, followed the Blue River, entered South Park, followed the Arkansas River to Bent's Fort, and left Colorado along the Arkansas and Smoky Hill Rivers. g. Green City Green City is near the site of Masters on the South Platte in Weld County. This site is dated in the 1870 's. One of the most fraudulently advertised colony experiments in Colorado's history, Green began his promotion about 1870. Approximately one hundred families from the Midwest and the South settled here in 1871 under the name of Southwestern Colony. Mismanagement and suspicion caused the colony to fail within a few years. h. Jurgens Paleo-Indian Site The Jurgens Paleo-Indian Site is located about ten miles east of Greeley and has been dated back to 8,000 - 7,000 B.C. This was a butcher- ing site to which ancient men dragged their kill . About forty projectile points, a like number of prehistoric bison, and other artifacts have been discovered at the site. i . Meeker Memorial Museum Meeker Memorial Museum (Meeker House) at 1324 Ninth Street in Greeley was built in 1870. This home was owned by Nathan C. Meeker, the founder of the Greeley Union Colony (see below). The home is now a museum. Meeker was killed in the Meeker Massacre. -53- j . Union Colony The Union Colony in Weld County dates back to 1869. Nathan C. Meeker and Horace Greeley promoted the Union Colony as Colorado 's first successful agricultural colony. The colony's corporate existence was terminated in 1880. 2. Mine Site Because the archaeological resources listed above are in the sur- rounding area, the possible existence of artifacts on the Keenesburg site is very real . With the cooperation and guidance of the State Archaeological Office, an archaeological search of the planned mine site was made by an independent firm, Cultural Resources Consultants (CRC) . The objectives of the investigation were to 1 ) inventory the archeological resources in the Keenesburg mine boundary, 2) assess their significance as additions to existing record, 3) recommend measures which would preserve, protect or salvage any resources which might be found, and 4) assure compliance with all relevant Federal and State laws for archaeological and historical sites. According to the CRC Report, "No sites are recorded for the project area in the State Inventories of Archaeological and Historic Sites, or in the National Register of Historic Places. No evidence of cultural resources was observed during the field survey. Extensive signs of recent human activity were noted, in particular, windmills, water tanks, fences, roads and cattle herds. These were judged to be of no signifi- cance due to their modern construction. This lack of prehistoric materials contrasts with some areas of Weld County, such as the Pawnee Grassland area, where sites are relatively common. It is likely that in aboriginal times the Project area was as unsuitable for occupation as it is now, offering neither cover, water, nor stable food resources. It may have been exploited seasonal in the pursuit of game, but no surface indication of such use remains." Since most archaeological or historical materials are buried and not visible from the surface, sites and artifacts may be uncovered as mining commences. In this case the State Archaeologist will be notified and steps will be taken to preserve and protect the find until an inter- pretation can be rendered. It is the policy of the State Archaeologist to act as soon as possible as to minimize the interruption of a mining operation. 20 Cultural Resource Consultants, Inc. , Letter of 10 November 1978. Refer to Appendix B for full text of letter. -54- E. Geological Characteristics and Physiography 1 . Physiography Weld County lies in the physiographic area known as the Great Plains Region. The general slope of the plain is to the east and southeast. The South Platte River flows through Weld County creating the types of topography that are associated with flood plains, terraces, and uplands. 2. Geology Weld County is located in the Colorado Piedmont Section of the Great Plains, which represents an early Cenozic erosion surface. The South Platte River is the major erosional agent of the Piedmont Section in Northern Colorado. Preceding the formation of the Laramie sandstone, a vast ocean covered the State of Colorado. During such time thousands of feet of marine sediments were deposited. The Pierre shale was the last and thickest layer. Regression of this ocean and change from marine to continental deposition can be seen in the Fox Hills sandstone and Laramie fo2r�ation. The seas withdrew due to the uplift of the Rocky Mountains. During the mountain making process, erosional processes by streams resulted in large alluvial fans (the Dawson Formation) . The formations which are most abundant in Weld County are the Fox Hills and Laramie sandstone formations. Ogallala and Arikee formations are found in the northeast portion of the county. Alluvium has been deposited in the flood plain of the South Platte River Valley and Terrace deposits have been formed mainly in the central portion of the county on both sides of the river valley. Rocks of the Precambrian to early Cretaceous age underlie most of the area at great depths. These deposits are in turn overlain by Pierre shale and generally dip westward. The Pierre shale consists of a thick sequence of fossiliferous marine shale, silt, and clayey sandstone, which contains numerous calcareous concretions. The upper part of the formation is transitional with the overlying Fox Hills sandstone. The zone of contact consists of grey sandy shale and shaly sand. The Fox Hills sandstone is composed of calcareous marine sandstone intermixed with dark-grey to black sandy shale and some massive white sandstone. The Fox Hills formation is the most important aquifer in the area. The Laramie formation overlying the Fox Hills Sandstone consists of yellow-brown and gray to blue-gray soft carbonaceous shale and clay interbedded with sand and shaly sand. It contains crossbedded gray to buff sandstone, which is slightly to well-cemented, and coal in the lower portion. The Laramie forms the bedrock across much of the mine site and is covered by unconsolidated Tertiary and Quaternary deposits. 21 Narrows Units, III , 4. -55- The unconsolidated deposits consist of dune sand, alluvium and terrace deposits dipping slightly westward. Figure II-1 shows the cross section of the mine site area depicting relationships of the coal seam with the overburden layers. The geologic formations of major interest that will be affected during proposed mining activities are the unconsolidated deposits above the Laramie sandstone, the Laramie sandstone and the coal seam itself. The Fox Hills sandstone lying 2002ieet below the expected maximum depth of mining should not be affected. 22 D.B. McWhorter, Water Resources and Impact Evaluation for Proposed Mine Site (Colorado State University, 1978). This report is given in Appendix A. -56- 8 1- O O 03 a r` r` r- tO ✓ C 7 7 7 '? v I I I I ° I IIj ~ j l• • I I r E 4, i I q E; I .:.: 1 � � . . I 1_._-. i tl• i � I V�- ^• I if! .: ,1 l t I .. i i 113 I , — a ,' I i I , ` O 4_) .. g � ; Ni 1 - ;gym 4- 'i' ' _ ~' r; I-.i l ; I . !1 X ic I W x ce.:./1 ,i, i• ‘y ifiris i it II i 1 5- (I i f jUNii I 1 I 1 T —'4. ;r'-'•'a Q I « ; 1 O I .. I b rl i ! Is o . ' I I a i_ I ..y , N . r. lc O. o I I I r i ut iJ i w Y m r I A 't i = N• . : 21 a I J . cI rrjjtl `f o t I i I O W N a) 7 O 'O C, 3) 3) h h h '3 Tr r 7 -r Q Q O • -57- F. Hydrology 1 . General Hydrology of the South Platte Valley The South Platte River Basin is a very hydrologically complex river system. The river has its source a few miles northwest of Fairplay, Colorado. From its source the river flows southeasterly for about 75 miles until its course changes to a northeasterly direction and con- tinues 40 miles through a mountainous region where it emerges from the Platte Canyon southwest of Denver, Colorado. Emerging from Platte Canyon, the South Platte River enters the Colorado Piedmont, a subdivision of the Great Plains, and continues as a plains stream through the Denver metropolitan area and on for more than 300 miles to its confluence with the North Platte River near North Platte, Nebraska. As the river traverses the Denver metropolitan area and the plains to the northeast of Denver, it is joined by a number of tributaries: Plum Creek, Bear Creek, Cherry Creek, Clear Creek, Boulder Creek, St. Vrain River, Big Thompson River, and Cache la Poudre River. The drainage area of the South Platte above Julesburg, Colorado, consists of mountainous regions at elevations varying from 8,000 feet to over 14,000 feet, high plain and foothill regions at elevations varying from 6,000 feet to 8,000 feet, and the Piedmont regions at elevations from 3,000 feet to 6,000 feet. Stream velocities are swift as stream slopes are relatively steep. In the mountainous regions the slopes on the main stem and tributaries vary from maxima of over 1 ,000 feet per mile to minima of 20 feet per mile. The average slope of the main stem in the plains area is about 8 feet per mile, with a maximum of about 15 feet per mile immediately below Denver. All tributaries draining the mountain regions are perennial streams which contribute to the regular flow of the main stem. Plains tributaries are often important contrib- utors to s-pring and summer runoff. In addition to the natural runoff originating from snowmelt and precipitation within the basin, there are numerous transmountain and transbasin diversions from the Colorado River and North Platte River watersheds. The more notable of these are the Colorado-Big Thompson Project, which diverts Colorado River Basin waters for use in the St. Vrain, Big Thompson, and Cache la Poudre watersheds, and those of the Denver Water Board, which provide municipal and industrial water throughout the Denver metropolitan area. The native surface flows of the South Platte River and imported supplies are not the only water source in the basin, particularly down- stream from Denver. There is an extensive ground water aquifer under- lying and hydraulically connected to the South Platte River. Recharge to this aquifer is dependent upon seepage from the river and its tribu- taries' stream channels, seepage from the many canals, ditches, and off-stream storage reservoirs, and deep percolation resulting from precipitation and the application of irrigation water. This ground water aquifer cannot be considered as an independent and separate source of supply as its continued viability is dependent upon recharge by surface water. In general , all recently available surface supplies in the basin have been extensively developed for agricultural , municipal , -58- and industrial uses. Ground water development has expanded consid- erably. However, its limits of utilization are being reached. Evidence of interference with surface water users is now becoming available. Water use throughout the South Platte River Basin is very inten- sive. Except during the heavy snowmelt runoff period of each year and in the times of floods, the waters are generally used several times before they reach the Nebraska border. Even with the intensive water use now in existence, there are times, generally in the spring and early summer of each year, when large quantities of runoff occur in the South Platte River. These quantities exceed the water needs and the physical ability to regulate or store them. Surface drainage pertaining to the proposed mine site originates in the Black Forest area northwest of Colorado Springs. The drainage system consists of the Kiowa, Box Elder, Badger and Bijou Creeks flowing northeastward to eventually become part of the South Platte River system. 2. Ground Water From the late 1940's through the 1950's the ground water showed a general decline in the Weld County area. The reason for this can be attributed to increased pumping coupled with near drought conditions. Installation of large-capacity irrigation wells between Henderson, Colorado, and the Colorado-Nebraska state line has decreased since the passage of the Ground Water Management Act of 1965 and the Water Right Determination and Administration Act of 1969. Figures II-2 and II-3 show hydrographs of selected wells within the Narrows Reservoir area. These hydrographs show the degree and occurrence of water fluctuation. Locations of the selected wells, labeled A, B, C, and D, are shown on Map #8. Wells A and D nearest the river show very little change, while well B near Bijou Creek shows about 25 feet of decline in level . Studies in the late 1940's in connection with seepage losses used a permeability of 315 feet per day for the local materials. This was based on pump-in and pump-out wateff3tests on holes in the vicinity of the site. More recent information indicated some materials in this general area have higher permeabilities. Five wells located in the Fort Morgan-Brush area had an average permeability of 666 feet per day with a high of 930. Fifty-one wells in the Greeley area averaged 719 feet per day with a high of 3,093. 3. Hydrology of the Keenesburg Proposed Site The Department of Agriculturg4and Chemical Engineering, Colorado State University, under contract, made a preliminary report of the water resources at the proposed mine site near Keenesburg. A total of 21 wells in the proposed mine site area in Sections 25, 26, 35, and 36 23 Woodrow W. Wilson, "Pumping Tests in Colorado, " Colorado Ground Water Circular, No. 11 , (Denver 1965) . 24 McWhorter. -59- in T3N R64W, Weld County, were drilled for use in a hydrologic study. The location of these wells is shown in Map #9. The wells provided a means 1 ) of identifying aquifers, 2) of measuring piezometric surface elevations in each aquifer, 3) to measure the transmissivity and storage coefficiency of each aquifer, and 4) to collect water samples from each aquifer. Several wells were planned as multi-purpose wells to be used in all of the above data collection activities, and others were planned only as observation wells for use during aquifer testing. Some of the wells were located inside the area to be mined and will be destroyed during mining. Others were sited outside of the mined area and can be used for monitoring during and after mining. Figure II-4 shows a student conducting tests. Water surface elevations in all wells were measured relative to a common datum and contour maps of the piezometric surface prepared for each aquifer. From these maps the direction of ground water flow and the magnitude of the hydraulic gradients was determined. These maps also assisted in identifying areas of groundwater recharge and dis- charge. Full scale pump tests, drawdown tests, recovery tests, and slug tests were used to determine the transmissivity and storage coefficients for the aquifers. Knowledge of the hydraulic gradients and the trans- missivities permitted computation of the quantities of flow through the aquifer. Figure II-5 shows the piezometric surface in the overburden as being relatively featureless. The overburden slopes to the northeast at a gradient of about 0.006 showing gradual discharge into the subsurface deposits in Ennis Draw. With a hydraulic gradient of 0.006, an avelrag2 flow width of 6,000 feet, and an average transmissivity of 7 X 10- ft. /minute, the discharge rate through the eastern boundary was computed to be 3 acre feet per year. The discharge rate through the northern boundary was estimated at 2.4 acre feet per year. Therefore the total discharge rate to Ennis Draw will be approximately 5.4 acre feet per year. The piezometric surface map of the coal seam Figure II-6 shows that the piezometric surface slopes toward the northeast at a gradient of about 0.004. Groundwater discharge from the coal seam to Ennis Draw was computed at a rate of 0.1 acre foot per year -- an extremely small val ue. Storage coefficients shown in Table II-16 indicate that the coal and overburden are confined aquifers. Because piezometric surface for the coal seam is lower than the piezometric surface for the overburden, the coal seam is believed to be a confined aquifer with little or no communication with the overlying waters. Also important in the estimation of the quantity of groundwater resources is the quantity of recharge. Recharge is extremely difficult to estimate accurately. The approach used in this program was to monitor groundwater level fluctuations with continuous water level recorders and attempt to compute changes in storage using the observed fluctuations together with the storage coefficients determined from the aquifer tests. -60- Existing water quality was determined by analyzing samples collected from selected wells. Before sampling, the wells were pumped to assure that the sample was representative of the aquifer water. In addition to rather complete analytical determinations on selected samples, the temperature, pH, and electrical conductivity of waters samples from all pumped wells were made. The CSU hydrology research study of the area shows the overburden aquifer to be of extremely poor quality with TDS readings exceeding 7,000 mg/l . Although the coal seam water appears to be of better quality than the overburden, it still would be classed as barely acceptable to unacceptable for irrigation. The quality of the water in Ennis Draw was found to be significantly better than the water in the overburden and coal aquifers. The same measurements were Viso made on a number of livestock and domestic wells in the vicinity. 25 McWhorter. -61- TABLE II-16 SUMMARY OF HYDRAULIC PROPERTIES OF AQUIFERS Aquifer Well No. Type of Test Transmi2ssivity Storage ft /min Coefficient Overburden 172 Specific Cap. 3.2x10-3 - Recovery 1 .1x10-2 - 122* Slug 9.3x10-3 - 117 Specific Cap. 2.7x10-3 - Recovery 1 .8x10-3 - 118 Drawdown 2.0x10-2 7.6x10-4 119 Drawdown 3.1x10-3 8.7x10-5 Coal 137 Specific Cap. 1 .0x10-3 - Recovery 9.7x10-4 - 116 Slug 1 . 7x10-4 - 61 Specific Cap. 2.6x10-4 - Recovery 7.3x10-4 - 62 Drawdown 2.2x10-2 7.2x10-4 60 Drawdown 1 .8x10-2 5.4x10-4 * Ennis Draw -62- c - I 0 - J J wn = I w owl'i . i� xf x Cc a t 0V = o u. r 0 x i x 13 21, ag= Fii -m;Wp 5k6.,=n= I F -: : = I S si" : Q g I v 1:1 _ a _ 33V3tl0S ONV1 M013N 1333 NI 3oYJWS 0NV1 M013S 1333 NI 13A31 N31VM 13A31 N31VM $ 7 g w 2 ° 2 $ rn w. w u, El ti3 p OW _� z ir„ - e u 0 I 0 2 0 - 0 j t72 -- is it° ET iii k L - iii t , 30Vd flS ONV1 M013B 133. NI 30V.lfflS O NV1 M0131 133. NI 13231 N31VM 13231 831VM 7 ciA I ��/ ;` � 3 I 5 14'1E . � rn VJ W f.}— '1--- o II ` I t o a 3 CO ANO A.?., i� �l� �' a°i�a jw a 0- I .. Ai,¢'a(0< E _ + iIi ,I J '1111111 crQ w w ;• 2 Ii' o W .. I - d 1r / • m e i , Q r W r� _ :I) ' ' t \ - s MI se t al W sz f�� \--4'.'11:'-\'. o ea ...a: . : a.`. . v - W a I (. ) -f _ i • —. li e ..: •+ •. G -. -ic �� 1w— W "4, • s �r /`� I� r�• chi •a / • �. • , v • zALE ; . 1 (� -su.©® • • +• • • i i • .e) • •' il • . • oav • I Q • ..... . ✓ / - N , • I , d Y x I '161. 7.: Al\[ (j.:\ L cb . i ,,-\ i :7) 1Y° .,c- _ 1� �° ) \,tip\ D I s alp V ts \ \'23 p` \ Q ,L., 24 oQ,. a ) I T .. wo , cc cc 5 \ . yews tA'� ��A '.eon AA�,-\_\\\-1 , ,i, " ° n V CM:.41 l O li yVA—3. ♦t,,. \� ° 96 i o ��\�0.\ \ 174. .�`\ \ i �\ \ V \, d\-_ 6E gl-\ .-) Il2-%t, c tv ri z..,:\\ I"..'‘ \k,_-)_, \c 134 ® \ `�/ ^'a e 137 / �\� °16.11 \ •L ;y \ , I_ 'cif` \ \ wean,.Ai r). I n..� 6c60 A 9„ area 1• / , O°� 132r` // ao �� rte, a B l `�I pia i1 XIf _ \ `�, \1 W ei-.1Y; <IY, . , �j )\ 36 ✓ 36 .w, o i \�J \ �� t�O f�� 118 , �q�,�_ :al t o 0 �5"�• 0 �I.7 119 I_` n , �\\V- ..,' \ " ': c I/ (� / e \, '�� I 1226 Y� GROUND WATER STUDY v / � / PROPOSED SURFACE COAL MINE m A �o / / `-- C ADOLPH COORS COMPANY, GOLDEN, COLORADO jT a v /p' i / _ O GROUND WATER OBSERVATION WELL IN COAL SEAM -.�,.J�� \ c q 0 PUMP TEST IN COAL SEAM � '\'4 ,1° O v' 0 GROUND WATER OBSERVATION WELL IN OVERBURDEN I �'y1 ��(\ ° �� \ 0 PUMP TEST IN OVERBURDEN _S--` ' " 0 ,,,� i • PIEZOMETER FOR AQUIFER TEST a��.�w a i 2� J� `I 3 EXISTING WELL ° v 'r e4 !1 0l'0 0 0 3 WELL NUMBER `1 "= ��'' a (.c o \\` r SCALE: feet I �C Df� °� �.\ � �! ', - 0 2003 4060 GOLD ` I ^� MAP OF STUDY AREA MAP #9 -69- f .gas i - 1,5, or 'a . ,,r.,._44::.41 —`� >j„. xP-x Colorado State University Personnel Conducting Tests on One of the Observation Wells FIGURE II-4 -70- 23 24 19 33 M to co 2 Q: ( DH96 173 \' 0E+116 '\ 26 25 14760.0 30 O1 DH 133 0W21 35 36 4780.0 DH1180 HI22o� T3N T2N 48800.0 2 I 6 / 22 0 Elevation in feet above mecn sea level Piezometric surface of overburden aquifer in October, 1978. FIGURE II-5 -71- 23 24 19 O O O O 3 3 Q M O in a co CC a) 0 Q / / DH162 CDH171 \ 26 25 30 :1 'oDHl34 oDH60 1 q DH132 I / - 35 36 31 0H1160) / . T3N / T2N / 2 I t 6 ' . Elevation in feet above mean sea level Piezometric surface of coal aquifer in October, 1978. FIGURE TI-6 -72- G. Climatology 1 . Regional Climate The Keenesburg mine site is situated in an area which has a "con- tinental " type of climate. Characteristics of the climate include low relative humidity, a large amount of sunshine, light rainfall (confined largely to the warmer half of the year) , moderately high wind movement, a large daily range in temperature (high day temperatu1rgs in summer and generally in the winter a few protracted cold spells). During the mid-1800's early settlers referred to eastern Colorado as "The Great American Desert" because of its aridness and short grass vegetation. The project area represents an example of the rain shadow effect because of the delicate balance of climate, soil , and vegetation. The mountains to the west cause moisture-laden air to release water in the mountains. Air now low in relative humidity continues to move eastward over the plains, and the water in the area is rapidly taken up by the air leaving very little moisture for the vegetation. This condition causes rapid cooling at night. Table II-17 summarizes the statistical climatic characteristics of the project area. Temperatures range from 109°F to -45°F with average seasonal temperature extremes occurring in July with a high mean of 76.4°F and during January with a low mean of 24.1 °F. The annual average mean temperature in central Weld County is 48.4°F. Severe cold waves are common on the eastern plains. The frz9st-free period for the three- county area ranges from 139 to 160 days. The average annual precipitation ranges from 11 .12 to 16.32 inches. Less than 10 inches of average annual precipitation is considered a desert climate. The maximum average monthly precipitation, ranging from 2.49 to 2.94 inches, occurs in May. (See Table II-17). About 70-80 percent of the annual precipitation is received between April and Septem- ber. The minimum average monthly precipitation occurs in January and ranges from 0.27 to 0.47 inches. Generally, areas that receive less than 20 inches of average annual precipitation periodically receive heavy rainfalls. The combination of heavy rainfalls and impervious soils typical of arid areas causes flash flooding. The pattern of mean annual precipitation is shown on Map #10. Relative humidity is frequently below 50 percent and will occasion- ally be less than 20 percent. Evaporation rates are high, causing rapid cooling in the evening§ at high altitude (thin-air areas) within rain shadows of mountains. 26 Climate and Man-Yearbook of Agriculture, U.S. Department of Agriculture (Washington 1941 ). 27 Climate and Man-Yearbook of Agriculture. 28 Climate of the States, Vol . 2, U.S. Department of Commerce (Port Washington 1974) as cited in Narrows Unit. -73- The prevailing winds of the plains are from the north or northwest in winter and from the south or southeast in summer. High velocities often occur because of the comparatively level and treeless character of the country. Winds of hurricane force (75+ m.p.h. ) have been recorded in the areas at least once a year. A U.S. Bureau Rain Gauge was placed on some reclamation study test plots on the mine site. The data collected is shown on Table II-18. The data starts with information from May through August,21978. It also includes the amount of irrigation used on the test plots. 29 W.A. Berg, Disturbed Lands Research (Colorado State University, 1978), 46. -74- CU . O1 .C a0 •r y.) • i U • i� .N. • Cr) CQ C a) CD Usr .22 CV U (1') rQ al 00 LL. CD 00 a) • O) .O (U •-. = X a) a) > N. >1L� >1e r r CL1 2N 2N 2N 4. * a) a1 u--• /O a0 •r tO N L n U CO p a) C . L> a cr C C O r- 1- o W Cr 7 O I • O) CC +a >, N a) N O = CC i S.- tO t1O ^ r 3 a t\ = L.L. La. C3 U O _ co N I N 7 b 2 N }a w w i 3 N m • ro J LO Cr) • IC— O O C E • c 7 h N CV LU N N N 4 I— .— (0 .. U cc a) U £ C — a) V N -c i a) 0- -C .O N • >1 O1 O1 N. Li -a E O)r > 7 4) N CV) Cr) N N = Q C 7 I— I. n N. a) a) L U = O) = 4.) rt) a) •— U * TS CD U • 7=• •l) O1 M = r 0 C O1 E s_ )o > -a) col Co co c a . CU C f" d' cr V N 0 U N as O i J..) S. = 10 Y 2 (O i O. a) 0 U w ++ a E L Y Z C )O 4-) 0. O 'O 0) 0 a a i C a.1 +) N ^ •^ •• O N S- S- C N Q C a) +> L )Z E > +s MS a) "O Ls, s_)O O R) i 1O c i i a).- i— O 'I- O J..) .r 7 a) O O i a) it N U N C QM 14-r CD 3 l t 4 = N -75- W > as .0 O • Lc 0. i 2 € 0 . N0 a U 0 U 3 L c-> N a 4.1 Or C -N 4.+0 N q •O L r N r r J C O L ' C W O � C ' O C r U r O • v 0 O • 0I GI rot. N C_ Q a J Y Gl Y .C V U QI O J N p N 0 • Y N 51 N > o 6 0.1 m �1G N 6 J •- J TI6 aC . L 0 N Y Y • 7 3 N V C.- CC V N = 2 JC r ow n N O• C E O N q.- 0 "JM C 0 C 0 L a Y N m O 100 0 OL 0 C N O € 60 14. ^ = .U..ao. • 4- O c C U N O. 4-r r C C N N. O A r .! 0...1 N C r 0 W.C .0-0 'ti L C 3 0 4-1 = 4..14.a UU Y C N r Y fl . Cl I) - Mali 41— 0.02 N Q N QI N L N V 6Y0 6J 41 Y LM Y L U66) 040 Z CI C C N 0 C E a O Y O C 0 as— at 0 S. UO.NL v1Y 41) 61J > 5.- M of IOO •0 0 VL-. 0001 i C C =a N r Yr rC p r rO Y L 10. 6$ M LL C IL$ 6= LL C LL= LLlL IV a O L_ 00a = u U01 C C I-- 0.- * - 0 .61 N O M L N V C C•.0= O _ �~ L M N R 00^r 000%r.rrOrtosgoseoseOIr u'Ofr+0uQu1 'O..ululCMM idol .= C L Y M 010 N in OJO C aD O M aO morn 60 CJrtO Va I�COO<O NM CV NN c C O C F. I.. O 00 OrrNNNMMM01666610u1 rO+0101.I�W 000,00.—.-0.5 NM 1] 0 2 Lr O NLO > W C H . 4-Yy L ✓ L N 6>. Or r 6 Q1 q Nd Y 4# Mul0C101OMullOul6Oululul x000 10r-.r�00 0 C 41 q C 10MOMNMMNNNNNNM NC•0 OSQ<u110 0 J i +W W C 0 0 0 0 0 0 0 0 0 0 0 0 0 0 000 00000 C .L a 0. L 0. CO U« C L r... = ... 0 u co,— = = W O L r+0 O4. 6 •(NJ Q 0 F.M. C c MM +04- • N 0 L >10 'Orr U C CM I�aW N 0e 10 CV00 0 L M N C l0 0 • W M NCI C WOO NCI 0 0 J r•M O 0 6 •0 0 0 0 0 0 0 000 r0 J 0 O Y .Y N 00. A C = C00 L0J O Y 014- C S. C r0 LL Vulr r N M 1010 W O1 Cr)Q 101Or�WOIO.-NMO a0f 0.-r.o M0rNMe0 10+0 CO C Y J N N M .......N N N N M ........•-•r r N N N N c r L N W - r 6U Y ✓ 60.0N q mi....-0 0 W W L • CO C W N U C. C >a 01 6 C .. W • W ra 0 0 0 W F- tn.0r L < 7 7 6 H -76- �5.0] 1 COi•fi5 .. \ / ^ ' N\ /r-. \ ` Car-order .1.000T0 dm FII r /,_ / NN ia. 6 Oeoc \ 00 K"'is Canyon 615E /� \ 23.28 — Po\ y i6' A BA E ?ure aos Gird. ≤s..e/ 7—`, • PO_ H u•77 s9[ i,/ ( __ ''?). V l / IPr a � —] l 6 rf Creel \ \ I (0.60 \ 15 \ ------!8.;n I 1 LO Po 1 \9nysooe \.n l I \ / i ,oi 9 NH PaYmv .5, 0 ` 1 1 F.CO n Ean, 6 avae I 1 'I 1 ,/ N \� / r \ / \ Greeley Mo15. LOPoibq / 9/ E oaM / 12.46 ,"\ NIPAOrr JS a 2 0 �)—� � I l I \ 01MSI(E L Bra / /� 1 / L / Grand Lclue IN,.\� xl 6J 1197.1;6"* on 7. Margo, 9 I m 6 1 a M �/ 7A . � e 1� ry e G Lou6 2a 9 1 1 C /MIMf !I► o ..6 � �� , � \Lenamo,e asE � yan, . ' V2de / 1; 7 l "]O/..I 9 v A V / \ Ft Lupton + e v S, 2 .3Yers:]e xsaf ; y ] ze]! sNar1 y _ A A\ •�— —J �—rap f 1 23.79 \ - .. 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Terrestrial Ecology 1 . Soils a. Overall Setting The soils of the northeastern plains of Colorado in general have developed under a temperate, semi-arid climate (average annual precipi- tation from 11 .12 to 16.32 inches per year) . The native vegetation consists primarily of short grasses interspersed occasionally with low-growing shrubs. These conditions have resulted in soils that are somewhat immature and have only moderate amounts of organic matter. The productive agricultural lands of northeastern Colorado have soils which are developing on parent materials from three main sources: 1 ) local outwash over broad, gently sloping pediments along the Front Range of the Rocky Mountains, 2) alluvial materials deposited along bottom lands and terraces of rivers and streams, and 3) relatively deep deposits of windblown silts and fine sands (loess) occurring in upland positions between stream channels. In addition to the above, relatively minor amounts of glacial outwash materials, water reworked loessial materials, and deeply decomposed residual geologic materials serve as parent materials for highly productive agricultural soils. The soils of the pediments and the soils of the river valleys vary widely in texture, depth, and degree of development, as well as in their chemical status. Generally, however, they are medium to moderately coarse textured, deep, and free of harmful accumulations of salt. The soils of the uplands are predominantly deep, medium textured, and also free of harmful accumulations of salts. The soils on the pediments and uplands which are most productive for agriculture are generally moderately well to well developed, since they occupy the level to gently sloping portions of these land forms. Soils of the river valleys range from almost no development in the more recent alluvium to very well developed on the older high terraces. The practice of irrigation in northeastern Colorado began initially on the pediments and valley lands due to the relative ease with which water could be delivered to them. Subsequently, many upland areas and additional valley lands have been brought under irrigation by development of more sophisticated distribution systems and use of wells as a source of water. Soils of the project lands show great variation in source, depth, and material . They were formed largely from wind and waterborne materials which have been resorted and reworked after deposition. The South Platte River Valley is underlain with alluvial sands and gravels which form the aquifer for irrigation well development. The bottom lands are recent alluvium, ranging from a few inches to several hundred feet in depth. They consist of a heterogeneous mixture of clay, sand, and gravel . Terraces occur in contact with the bottom lands and were formed from calcareous alluvial deposits on old stream terraces. -78- Most of the proposed mining area is covered with windblown fine sand. The valley areas, located outside and adjacent to the site, are residual or aeolian in origin. They have been deposited and reworked over periods of time. Due to their origin, they may range in texture from coarse sandy loam to clay. Most are covered by a thin layer of loess (windblown silts or fine sandy materials ) . b. Soil Genesis and Morphology Some generalizations regarding the land resources of the project site can be made in relation to their most significant characteristics. The lands of the terraces of the South Platte River, as well as a major portion of the irrigated uplands, are generally well suited to irrigated agriculture. Moderately coarse to moderately fine soil textures predominate throughout the unit area. These soils are generally well drained, both internally and externally, and a minimum of chemical deficiencies or problems exists. Natural fertility is moderately high, and with intensive use of fertilizers and soil amendments (standard practices in irrigated agriculture in the lower valleys), fertility levels are maintained at a very high level . Some localized problem areas of restricted internal or external drainage do exist; however, the most common problem in this regard is the result of inefficient irrigation practices, resulting in some accumulations of surface waste water in places throughout the general area. The soils of the areas within the Central Colorado Water Conser- vancy District have not been categorized in detail for the entire district, since the area involved is large and contains widely varying soil types. Part of the areas involved lies south of the South Platte River in the vicinity of Bijou Creek, and the detailed information outlined above includes these areas. It can safely be stated, however, that the lands lying within this district, which include large areas of the South Platte Valley from Denver to Greeley and parts of the pediments lying to the north and west of the valley, contain well over 121 ,000 acres of some of the most highly productive medium to moderately light-textured agricultural soils of eastern Colorado. There are 21 soil association groups found in Weld County. They are described as follows by soil association number: #3 Travessilla-Rock outcrop association: Warm, shallow, well drained, sloping to steep soils and Rock outcrop on upland breaks. #18 Fluvaquents-Fluvents association: Warm, deep, poorly drained and somewhat poorly drained, nearly level soils on flood plains and low terraces. #19 Runn-Haverson association: Warm, deep, well drained , nearly level soils on terraces. #20 Ascalon-Platner-Stoneham association: Warm, deep, well drained, nearly level and sloping soils on upland plains. -79- #21 Vona-Olney-Dwyer association: Warm, deep, well drained, gently sloping to moderately steep soils on upland plains. #25 Bankard-Wann association: Warm, deep, well drained to exces- sively drained and poorly drained, nearly level and gently sloping soils on flood plains. #26 Briggsdale-Terry association: Warm, moderately deep, well drained, nearly level to sloping soils on upland plains. #27 Weld-Adena-Colby association: Warm, moderately deep, well drained, nearly level and gently sloping soils on upland plains. #30 Fluvent-Sampson associaton: Warm, deep, well drained, nearly level soils on flood plains. #59 Camborthids-Torriorthents-Haplargids association: Warm, dominantly shallow, well drained, steep soils on hills, breaks, and canyons. #71 Ascalon-Vaona-Truckton association: Warm, deep, well drained, nearly level to sloping soils on upland plains. #79 Mitchell-Keota association: Warm, deep and shallow, well drained, sloping to steep soils on upland breaks. #80 Rosebud-Canyon association: Warm, deep and shallow, well drained, sloping to steep soils on upland breaks. #148 Valent-Vona association: Warm, deep, excessively drained and well drained, gently sloping to moderately steep soils on uplands. #172 Renohill-Shingle association: Warm, moderately deep and shallow, well drained, gently sloping and sloping soils on upland plains. #173 Ascalon-Olney-Vona association: Warm, deep, well drained, gently sloping soils on upland plains. #174 Nunn-Dacono-Altvan association: Warm, deep, well drained , nearly level soils on terraces and floodplains. #175 Kim-Otero association: Warm, deep, well drained, gently sloping soils on upland plains. #181 Haplustolls-Argiustolls association: Warm, shallow and deep, well drained, nearly level to moderately steep soils on terraces and uplands. The soil association groups described above are the most current soil group classifications as designated by the Soil Conservation Ser- vice. These soils are not listed on Weld County Soils Maps (See Map #5) -80- by their association number at this time. Their listing will be helpful when a new "General Soil Types Map" for Colorado is available in the near future. Detailed county soils maps will also be available. Pres- ently general soil type areas can be located only by comparing the individual soil association group descriptions with the descriptions of the general areas as shown on the Weld County soils maps. c. Soil Type Influences on Wastewater Treatment Deep sandy soils which have sandy subsoils and allow rapid percola- tion of water are generally well adapted to the support of septic tank filter-field for the adequate treatment of effluent from individual sewerage systems. As the top soil and/or subsoil becomes more shallow and less sandy (more clayey), more restrictions in soil permeability and filter-field adequacy are encountered. In areas where percolation is slow or moderately restricted, it is necessary to construct more generous septic tank filter-fields in order to treat sewage wastes adequately and maintain sanitary conditions. Very heavy (clayey) soils which exhibit severe restrictions in water percolation are not suited to septic tank systems, and sanitary conditions usually cannot be main- tained even with the use of oversized filter-fields coupled with prudent usage during times when precipitation and soil moisture content is abnormally high. Where there are thin porous soils in conjunction with fractured bedrock or shallow bedrock, pollution problems may occur30from septic tank systems, due to excessive leaching into groundwaters. Sewage treatment lagoons, on the other hand, are best adapted to areas which have heavy soils. The construction of aerobic lagoons in sandy areas sometimes presents performance problems because the lagoons do not seal in sandy soils and water retention for adequate periods is difficult to maintain. d. Soils of the Project Area The Keenesburg area soils are made of sandy loam soils. The soil series, the Valent and the Osgood, make up most of the area on the proposed mine site west of Ennis Draw. The Osgood is a deeply developed soil with a slight amount of clay in the subsoil . The Valent has shallower soil development as evidenced by lighter colors in the subsoil with no increase in clay depth. Both are extremely sandy. A detailed soils description follows in Charts II-1 through II-4, and a detailed laboratory characterization of the soils is given in Table II-19. Boel and Loup soils were also found in the proposed site but not to the extent of the Valent and Osgood. They are included in this report for descriptive purposes in identifying the soils of the area. Table II-20 shows detailed laboratory analysis of core samples taken of the over- burden. 30 Water and Sewer Facility Plan. -81- CHART II-1 OSGOOD SERIES SOIL DESCRIPTION TAXONOMIC CLASSIFICATION: Loamy, mixed, mesic Arentic Ustollic Haplargids. The Osgood soil as mapped in the study area is described as a "variant" of the typical Osgood series. The typical Osgood soil as mapped in the south Weld County soil survey has a thicker and finer texture subsoil than the Osgood variant as mapped in the study area. As mapped they consist of deep, well-drained soils that formed in wind-laid sands. They occur on smooth plains that have slopes of 0 to 3 percent. Osgood soils are usually adjacent to or near Valent soils which do not have a B horizon. Profile description of Osgood sand, variant, 0 to 3 percent slope, as obtained on the study ara (3400 feet west and 100 feet south of the northeast corner of Sec. 36, T3N, R64W). (Site #1 on soil map) . ALL -- 0 to 5 inches ; brown (10YR 5/2) sand, dark grayish brown (10YR 4/2) ; moist; single-grained; loose; netural ; gradual smooth boundary. Al2 -- 5 to 18 inches, brown (10YR 5/3) sand, dark grayish brown (10YR 4/2) moist; single-grained; loose, neutral ; gradual wavy boundary. A3 -- 18 to 32 inches; brown (10YR 5/3) sand, dark brown (10YR 4/3) moist; single-grained; hard when dry, friable when moist; neutral ; gradual smooth boundary. B&A -- 32-44 inches; brown (10YR 5/3) sand , dark brown (10YR 4/3) moist; massive; hard when dry, friable mosit; neutral ; clear smooth boundary. B2t -- 44 to 49 inches, brown (10YR 5/3) loamy sand, dark brown (10YR 4/3) moist; moderate coarse prismatic parting to moderate medium subangular blocky structure; hard, friable; neutral ; clear irregular boundary. C -- 49 to 60 inches; pale brown (10YR 5/3) moist; massive; slightly hard dry, very friable moist; slightly alkaline. -82- CHART II-2 VALENT SERIES SOIL DESCRIPTION TAXONOMIC CLASSIFICATION: Mixed, mesic, Ustic Torripsaments The Valent soils consist of deep, excessively-drained soils that formed in wind-laid sands. They occupy gentle plains that have slopes of 0 to 9 percent. Valent soils are near the Loup-Boel and Osgood soils. Loup-Boel soils are poorly drained. Osgood soils have B horizons. Profile description of Valent sand, 3 to 9 percent slope, 900 feet north and about 2,000 feet west of the southeast corner of Sec. 36, T3N, R64W (Site #4 on soil map). Al -- 0 to 5 inches ; brown (10YR 5/3) sand, dark grayish brown (10YR 4/2) moist; single-grained; loose; neutral ; gradual smooth boundary. AC -- 5 to 13 inches; brown (10YR 5/4) sandy, dark grayish brown (10YR 4/3) moist; single-grained; loose; neutral ; gradual smooth boundary. C -- 13 to 60 inches; brown (10YR 5/4) sandy, dark grayish brown (10YR 5/3) moist; single-grained; soft, loose; neutral . -83- CHART II-3 LOUP SERIES SOIL DESCRIPTION TAXONOMIC CLASSIFICATION: Sandy mixed, mesic, Typic Haplaquoll The Loup series consists of deep, poorly drained soils that formed in sandy alluvium. Loup souls occur primarily along drainages in the sandhill area and have slopes of 0 to 3 percent. Loup souls are near the Boel and Valent soils. Boel soils are stratified and somewhat poorly drained. Valent soils are excessively drained and have a light colored surface layer. Profile description of Loup loamy sand from an area of Loup-Boel loamy sands, 0 to 3 percent slopes. 01 -- 2 inches to 0, undecomposed organic material , chiefly grasses, sedges, and roots. Al -- 0 to 16 inches, very dark grayish brown (10YR 3/2) loamy sand with few fine distinct reddish brown (5YR 5/4) and dark gray (N4/) mottles, black (10YR 2/1) moist; weak fine granular structure; soft, very friable; calcareous; moderately alkaline (pH 8.2) ; diffuse boundary. Cl -- 16 to 40 inches, light brown gray (10YR 6/2) loamy sandy with few fine distinct yellowish brown (10YR 4/4) mottles, grayish brown (10YR 5/2) moist; weak fine granular structure; soft, very friable; calcareous; moderately alkaline (ph 8.2) ; gradual wavy boundary. C2 -- 40 to 60 inches, light brownish gray (10YR 6/2) sandy loam with common medium distinct yellowish brown (10YR 5/6) and gray (10YR 5/1) mottles, grayish brown (10YR 5/2) moist; massive; hard, friable; calcareous; moderately alkaline (ph 8.0). Typically these soils have free carbonates at the surface. The A horizons have value of 3 or 4 dry, 2 or 3 moist and chrome of 1 or 2. The C horizon, to a depth of 40 inches or more, is a loamy sand or sand. -84- CHART II-4 BOEL SERIES SOIL DESCRIPTION TAXONOMIC CLASSIFICATION: Sandy mixed, mesic, Fluroquentic Haplustoll The Boel series consists of deep, somewhat poorly drained soils that formed in stratified sandy alluvium. Boel soils occur primarily along drainages in the sandhill area and have slopes to 0 to 3 percent. Boel soils are near the Loup and Valent soils. Loup soils are poorly drained and are mottled at the surface. Valent souls are excessively drained and have a light colored surface layer. Profile description of Boel loamy sand from an area of Loup-Boel loamy sands, 0 to 3 percent. Al -- 0 to 14 inches; grayish brown (1OYR 5/2) loamy sand, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, loose; calcareous ; moderately alkaline (pH 8.2); gradual smooth boundary. Cl -- 14 to 31 inches; pale brown (10YR 6/3) loamy sand stratified with thin lenses of sandy loam, brown (10YR 5/3) moist; few fine faint light yellowish brown (10YR 6/4) moist and yellowish brown (10YR 5/6) moist mottles; massive; soft, very friable; calcareous; moderately alkaline (pH 8.4); diffuse wavy boundary. C2 -- 31 to 60 inches; very pale brown (10YR 7/3) loamy sand stratified with thin lenses of sandy loam and sand, pale brown (1OYR 6/3) moist; common medium sized distinct yellowish brown (10YR 5/8) moist; brownish yellow (10YR 6/6) moist and gray (10YR 5/1 ) moist mottles; massive; soft very friable; calcareous; moderately alkaline. Typically these soils have free carbonates at the surface. The A horizon has value of 4 to 5 dry, 2 or 3 moist and chroma of 1 or 2. The C horizon has value of 6 or 7 dry, 5 or 6 moist and chroma of 2 or 3. It is a loamy sand or sand . The need for sampling, classifying, identifying and analyzing these soils types are for assessing the reclamation alternatives. -85- OL ONMO 01O CO IDr r IOM LO 1---. 00 NCO CO MN. L) d' tO L CC• 0- NOt O1 TM N CO 1- 01 cr N ^ I- Nr 4!) NO11, 1, up d' \L u szt V V M Oct 1� On O met d•• • . IO• . OOO eO 0 Q • U d 0 0 0 0 0 0 0 0 0 0 0 0 O O O r 0 0 0 0 0 0 0 0 O CO W NIO Ve 01 Or- Or- a) NOO r1-- O n LC) NNI0O C 0 L O_ M O r 0 0 0 N r r r O 0 M O O O r N 0 0 0 0 0 VD O r r N N N M N I N r 1, 4l 1 N N N N C d N C1 0 ° 0 0 0 0 0 0 0 0 0 0 r 0 0 r 0 0 0 0 0 0 0 ° 1)31 O OO LAD O I{) o VD IONO. Ncr� lD l0 10 IOO I rM I MONMN Y CL CV 01 r lO r O IV 0101 O V on 0101 � Q r r- r- i-r N r-� r r r N r O O_ Ca- O M M r r r VD N r r r r CO N N I O M r c Y CL ZC IC) N M O r r r O O_ cl 2 d 2 U \I F M CC▪ . e, OC .crLON 01 O OOMM e, yrN O1 V N IO IOIOIO c' r CD CO O 0 0 0 0 0 0 0 0 0 0 0 0 O O O O O O 0 0 0 0 0 0 G of J 01 — ✓i N I 1-I U ION c7 NNN N CV r- NNN crNr NNN crI, MMO r-I W 0 0 0 0 0 0 0 0 0 0 0 0 O O O O O O O O O O .-- L W J O Q \ I- i OI0 IO ONO O c• IOM M1, rd• IO X01 ON M N V R Q 1Dn n n ^O ID n1` nr ^ . 1\ n lO n1\ up nnn n +) . O N V 01 1, 1, 1- 1- ^ V O f' N 00 UD CD N M I O O. C Or Myr a + Or-NMch + O + crr t (U n-- I I 1 I I CA Mil 1, 1 I M I I cr Mill 0— OIn ON c7 V O ales.. --ct OOr Od' r CD CD d' NN CY M r M V r N M r r 0 OQ � 4-) a") 5- r N 015 Y r N N r V U r N M r N = Q Q CO m O U Q C ¢ m co U ¢ 4 O Q Q U G m on on O O a1 V cr A en rci Z 04-' 0y) C #' C +Y O V p r O •r O cu r 0)N 0)v) °-) cn - v) 0)v -86- ou, o > rts> 0 In o Q a. l- 0 Ln� - M M ctO) e. CO N. C1 ) N a 1/4.0 d• N 0 03 -0 4-) LI_ a r r r r r r r N Rl E .C C U +1 O CU a N E i � o co i_cl t 'O U to LO in LC) Ln to t0 S r E = a c.) a 0 a O co 0 0 O 0 ea 0 t6 U = OE \ V S.- E Lo N 0 E N.. N. OJ N e al i cc)4F CO. O Cl a N V e N M LO M N0 a N -C N I + i al Lot ° E t0 O O tO N. 0 0 W til C NO a 0 r r•- 0 0 r r 0 i al N _C C 0) U •o E \ rV i i al N CO CO N LO 00 e In E +1 La r O) N. CO 0 CO t0 I 0- C1 Y a r n +.1 r (1)4- U O N 41 0 CO rn ra S. N �1 +.) r0 O 0.1 w a 01 01 LO In N. IN tD X CU 0) a N CO0. C C N . D_ a V 0 Cl 0 C) rn •r C v +1 0 +l • R r6 CO OY CIIZi S. N -0 O C k M 0 MS x 4-) E H Z Cl- R i O 0qL1 n 4-) E a X +1 C w ra v 3 v it J C C Ua Q CL MI O O -C ra N M L I— +1 +) 0 a I. N. n Ln N. O IN 1/40 N 5- a 0 0 0 O CO 0 0 r O 0 CU _D O U 3•Q 5r0 a +i-) a r E 0 -O ra 0 i a) C1 U S- 4- N V i L • 0 -al 5. V U N C V N N to N N i }) +1 U w 0 00 0 0 0 0 0 v r E .C a) 4- r 4-) N S. Cl al 0 a E N. C C 0 1-. eIn to in r M• O 0 O U 0 a N. N. n n N. N. N. tO +1 •O -O = U) C C C E +1 i O t^ -0 i E CU+1 a O C1 N a) O-. C U +1 +1 •O in CI L.., N al = r6 -0 -o N S. ra 0 a) W C) N Cl CI C) C W U) 3 L Y 4„) +1 r -1 ,I.1 C) •te) N '.) 4-1 S- ra a C N••—• Cl •r N •r Cl • C1 •r C1 3 C U) 0 U N U tn U in U u) U in U U) U in 3 3 al 0 N CO O COO ra 0 ft O COO ra O MO Si 0) .C W a 4- a 4- a 4- a 4- a 4- 0_ )~- a in C) O a i 5. E 5- 5 S- 5 S. E 5- 5 5- 5 5- E a) +1 +1 S. O O O 0 0 O O O O 0 0 O O O 0 C +1 y C) = N c J in o N U N O N o CO O CO O •'- CC$N E •� i I ra Cl a1 V al +1 • +1 +1 U"O LO LO C) .O C ell t150 E C ) N on N a) M M M -a = CO i i .C r0 O 0) +1 +1 Y Z 03 + = O 5- X N 00 CU CU 00 I U O U C U a In 0 Z ui E 1— O al 0) N N ^ 0 OW a C1 O O) 0 Cl 0)N N MV) 0 E 0)1') r N _ in 0 7 7 0 J 0 7 rI NI MI d•I )nI -87- \I ^ Lb v CO Cr) r r 0 v CV r Lb r on r r R 4-) A CD LO L i M ES 6- n N u-) LO O N 7 Al W y N 0 M r r M N O in on O r N O r O CO 0 N M I- n cm n7 '0 ^ r •v N Ln LO O O a' N LO V Ln J H O N LL � 7. rca O M R cF LO N CO d' M cr O% CO L O N CV r- N M N Ln LO 0 0 LO LO Z N U r - .- 0 •r- ..-4 N }- >1 d NI it 1--• CC ¢ 4-1 oQ O 6- M N u6Ul 01 Ln 6- N r r 41 M N UP M M LO M LO CO N. LO W o• N N U Q / K ) Q v 2 U V ✓ {..) -o Ch N L`l re) f M I 1- N N O l r M M L.I n N C L n O 1 V N I- CO CC 0 s- C OO, 010100 OOl Ot 00101 01010) T 0101 001 OOOO O ro m G 0_ in cc O co GC J 01 _Cr- CO N 6- 01 ^ ^ ^ ^ M C' O V N CO 10 O .--I 4-) • LO r M 6- cr + Ln r N M V + Ln r + ch r + r r N N M LO L d C II I 1 I Ol I 1 I I 1 I- 1 I C1 I 1 C' Mill - O In CO N Q cY O LO I- t\ n a' 0 Ln r O 6-r 00 V N CO LV O r, C.-- r- CO cY rCVC) r- r- CO Lil J 0 Q I- C ON Q .0 .0 o 5- r N 06 +) rN r- CV r- r- 4-.) U r N CO r N 2 C Q C 0] 0] U 2 Q G 0] 0] U C Q O ¢ Q O Q CO 0 00 U U N M 6- N r E a 4h a M Z N N C 4 C N 0 0 O 00 + r 0 •r) O V• O 01 N 'O- V) MCA Cr)ON b N ID N N O O > > O -88- CD 4-1 (.) \ in co e i co O e N CO N N1 r N r r- r- .— N N N r R C yy 0 rO CI N N N S- L. CO 01 C• O N N. CV 7_ 7-P170 r N N N N CO Cr) CO N rIZI N C C it a) r O a) Co• CO co 01 to to CO N O ^ N N e M M CO R t0 t0 L[) C ID N C it r i N re- N N 0 .---. u) N 0 -C •_ 4-3 • 4 in E 0 O T d- It L +) N 41 N Q4-1 a") E O) Zia — Qt t0 t0 t1) 01 O) 01 01 al E a) Cc a .a.. N N 0 1 rt N -0 7 0- 01 v -C r• a) L 0 a) i L ✓-+ 4.1 -0 4-1 N W rO it 01 M Cr) H• 0 01 O CT >1 L J 0- ) V) CO Ol al 01 al CO 01 CO -a CO 0- V I— N N C -C 4' E 5- 0) N C 4-) 0) N L 'O = 4•) . O C L O) CI a) C 3 E N S. C a) O 4-) N 4-) -o rO +) 4.) 4.) Y a) C 4) 4) 4-1 S- = N•r N•r CO ..- N .r N •r N .r Q) •r E d O (.3 N U N U N U in U N 00 U N L 3 N r0 O COO rd O -'0 0 COO COO coo a) 4- 0_ 4- 0. 4- 0. 4- a 4- 0_ 4- 0. 4- 0. +1 N S- s. E i E L E S. E S. E S- E S- E a) C O = 0 = O = o = O r 0 = o = 0 -o O = (c) U MO MO Nu N O MO MO ..- a) N N C N in 4-) 6) • 0) r N S_ U N LO t0 t0 r LO t0 r 4--` co N Cr) N N M M CO +1 0. N R 0 S. E . z co O 0 Cu Cu O U I 0 00 C U d N 0 Q) v N 4) N O N 0_-N 00 N N O)N r N r N OW) J N OW) r N 0 N -4O r0 N J O 7 rI NI N 0 7 > 0 -89- a R) M M N N U CO LO LO tO r Ln i C QJ r N r n >. L O) O LA N ir LC) O QJ N LO O C _ lL Cr Cr VO' ir QJ OD r0 QL --- E N 7 N N CO to C N N• M N N E N N Cr) N O N U- 0 Z O CU I-i L CO N N r N rM NCr H 0 r r C W I- 0 Q C Q co = an L V M V to U Y • i l6 r '— O r C QJ O 0 >. U H Q C 0 CO Q -c J i- LO LC) LO V d I I I I O1 CU O O 0 O rl I r w = J O CO N Q r r I- 0 Q ..7c. Q = B Z Q) V Q) i-' QJ +) QJ O +' O 4-' C +J C 4 r O•r O •r• QJ•r Q) •r •O O)(n an t) r N r N 0 0 > >N -90- TABLE II-20 (Page 1 of 2) LABORATORY DATA ON OVERBURDEN • E a 3 ae _ ' a . . . r : a - - - a - - - - - - 3 a e e added maa a 46 _ e a . mome o d e a ode . e a a a 00000 000 i24 0 0 a a. ' r N . a ra . 4 Nm 4 4 4 ary4 a 4 - 44 a . S ^ - - - - - .. _ 4 4 2 I e r . e . _ . 24 £ : . : : £ _ _ _ a 4 44d N —d4 _ . r o a m N . I r - - 4 dm; . . a . a ei 9 a 44444 44d 4dd 4 4 444 44444 , p4. m 4, 774" t 3 i S —'mg •3" V§ . uB , ._ S .: . . . ., e e g a emu . .- . ., a a I 81` o a m % ii At a a a 9 x l g l a - « 024 ; 4 twig _ al -91- a a - 96nn = 4999 - a -a “ Pp_ 6666 evoem e < oem 6 6 2 4422 22223 ., 4 n 2 R 4 n 4 n 4 @ n ry 49 , 999 _ T 3 r r ; ; Om 3332 .., 32224 em4 3 4 pp _ 4 ry 2 3 3 2 3 — ^ 2 m ry N r • ry 3. 4.5 m _ rv _ n _ ry G. n _ th 4nry _ ry ry .- ry — N N „ 4 — n n .: 6 el . : ≥ m m 4 e n 0% c.a) O- i 4649 4 .i994 in' .., 44 .a ry n m _ .., a P. 0 2 - V. 4 r 4 4 ry - - ; ^ N ---� ry v _ 449 _ n 9 9 4 4 pi 9 _ 9 4 m W ,., sx _ S a3 ; „ n a 656 ,—I Zr. ry n n C — _ _ _ _ _ ry 99w 4 m n 4 .. £i 7.: ": ".' n ry .o m ry ry N n .., 4 n m .+ .a n .o m m .. m .. .� .. .. . m .. .. m .. m .. .. .. .. .. .. A ri . g 3 _ Faa� . cN3 76e C: F � S — c 3 't a 3-12 $ a _ _ •— r , 8 i i : g • S 8 .., 14T- 434.17::4 7 m J � 7 .a 6 7 6 9 & -_ Y 8 6 _ _ ry A 21: 223 ,. -3333 a- 4 ^ ^ _ -92- 2. Vegetation The purpose of Colorado State University's study31 of the Keenesburg mine site was to provide a rangeland inventory and plant characterization. The information provided was then used to predict impacts that might result from surface mining operations on the site. Mitigating and rehabilitating activities are recommended to re-establish stable, productive, and publicly and environmentally acceptable regrowth. Figure II-7 shows the CSU revegetation study in progress. The vegetation of the Weld County area is situated in the Upper Sonoran-Plains Group Life Zone. This zone is dominated by short grass prairie. The most important species of the undisturbed prairie are the gramma (Bouteloua gracilis) and buffalograss (Bachloe dactyloides). In addition, several faciations result from combinations of the major dominants with western wheatgrass and threeawn. Thousands of acres of the original plains have been used for dryland farming and grazing. The present community, i .e. , the short grass climax, has been described as a disclimax residing from overgrazing. The climax is thought to be mixed grass prairie. In the proposed mine site at Keenesburg, the sandsage-prairie sandreed plant association was the only vegetation type mapped on the upland which is classified as a Deep Sand Range Site in the Soil Conser- vation Service system and includes all of soil mapping units 1 , 2, 3, 4, and 7. A saltgrass-alkali sacaton meadow association meanders through sections 30 and 31 ; this meadow is classified as a Sandy Meadow Range Site in the Soil Conservation Service system and includes all of soil mapping unit 6. A complex of Sandy Meadow and Deep Sand Range Sites is found in soil mapping unit 5. One hundred plant species (Table II-21 ) were found in the six sections surveyed (sections 30 and 31 of T3N, R63W and sections 25, 26, 35, and 36 of T3N, R64W) . Specimens of most of the species were collected and mounted. Identification of the mounted plants was verified by personnel of the Colorado State University herbarium. One of the species found in the meadow (200 feet south of the windmill in section 31 ) was tulip gentian (Eustoma gradiflorum); it is listed as rare in the compu- terized Plant Information Network of Colorado State University. However, this species is not listed as rare on the Colorado or national lists of rare or endangered species. The Keenesburg area sandsage-prairie sandreed association, which is classified as a Deep Sand Range Site in the Soil Conservation Service system, occurs on Valent Sand and Osgood Sand soil series. Sub-site differences and variations in range condition create much heterogeneity in the association. The aspect is predominately sandsage, which pro- vides a crown cover varying from near zero to about 20%, and a density up to about 3,000 plants per acre. Sandsage is absent to rare on some 31 W.A. Berg, Soil and Vegetation Inventory Reveqetation Research Keenesburq Area (Colorado State University 1978). This report is given in Appendix A. 32 H.J. Oosting, The Study of Plant Communities (San Francisco and London 1956) as cited in Narrows Unit. -93- TABLE II-21 PLANT SPECIES FOUND (Page 1 of 2) Abfr Abnania gnagkan Nutt. ex Hook. Snowball Agda Agkopyn.on daaydtachyum (Hook. ) Scnibn. Thickspike wheatgrass Agsm Agkopynon 6m.itlui Rydb. Western wheatgrass Alte Attium .texti.2e Nets. S Macbk. Textile onion Amco Ambnae.i.a. cokonop.igotia T. S G. Western ragweed Anha Andiapagan hatta Hack. Sand bluestem Arfi Antem.is.ia Pli4atia T0A/L. Sands age Arin Atgemone .intenmedia Sweet Prickly poppy Arlo Aru.atida tongis eta Steud. Redstem threeawn Asce Aatluigatua ce.amLcas Shetd. Ceramicpod milkvetch Aser Aatex etico.ides L. Heath aster Asgr Ast4agaeus g utcL L4 Nutt. Milkvetch kvetch Asla Aa c2ep.i.as tatigotia (Toni. ) Rag. Milkweed Bogr Bouteeoua gnacLUo (H.B.K. ) Lag. Blue grama Bohi Boutetows h..Muta Lag. Hairy grama Brte* Mamas .tectokum L. Cheatgrass Buda Buchtae dactytoLdes (Nutt. ) Engetm. Buffalograss Calo Catamovitaa tongLgottia (Hook) Sciibn. in Hack. Prairie sandreed Cahe Canex hetiophLta Mack. Sun sedge Chle* Chenopodium teptophyteum Nutt. Slimleaf goosefoot Chvi Chkyhop4L6 v.iftoea (Pux h) Nutt. ex DC. Hairy golden aster Ciun* C.Uus.ium undutatum (Nutt. ) Spheng. Wavyleaf thistle Clse Cteome een/cutata Punish Beeplant Crte* Craton .texen&-is (Ktotach) Muett-Ang. Texas croton Crfe* Cryptantha gendteni (Gxay) Gxeene _ Fendler hiddenflower Crja Cryptantha fames u. (Tone. ) Payson James hiddenflower Crmi* Cryptantha minima Rydb. Smallflower cryptantha Cysc Cypekue schwein%tz.i,i. Toni. Schweinitz flatsedge Cuum* Cue cuts umbettata N.B.K. Dodder Devi Detph nium vineoccns Nutt. Plains larkspur Dist DL6tichti.a &ti.Lcta (Toni. ) Rydb. Saltgrass Elca Etymu6 canaden.sLs L. Canada wildrye Eqva Equ.ihetum va Legatum Schteich. Variegated horsetail Eran* Ehiogonum annuum Nutt. Annual buckwheat Eref Eniogonum eggusum Nutt. Woody buckwheat Erfl E%iogonum gtavum Nutt. Yellow erriogonum Erbe* Eni.gen.on be idiaatw .m Nutt. Annual Fleabane Erpu En,igen.on pumitus Nutt. Low fleabane Eugl* Euphonb.ia gtyptoapeuma EngePm. .in Emory Ridgeseed euphorbia Eugr Eustoma gnandigtonum (Rag. )ShLnneu Tulip gentian Evnu Evotvutub nuttattLanue R. S S. Nuttall evolvulus Feoc* Fes.tuca (Vutpta) oetogtoka Watt. Sixweeks fescue Glle Gtycynhhiza tepLdota Pwcah Licorice Hasp Haptopappua 4pLnutobu4 (Pugh) DC. Goldenweed Hepe* Het,ianth.us petLotatbas Nutt. -Prairie sunflower Hoju Hohdeum jubatum L. Foxtail barley Juba Juncae baPt i.cua W.ittd. Baltic rush Kosc* Kochia 4eopaki.a (L. ) Sehnad. Summercrypress Lapo Lathyn.ua potymokphu6 Nutt. Showy peavine Lare* Lapputa kedowskii (Honnem. ) Greene Stickseed -94- TABLE II-21 (Page 2 of 2) Lasc* Laetuea aecXLota L. Prickly lettuce Lede* LepLdLum dens.Ld.Co/uam Sehitad. Prairie pepperweed Lelu Lesqueketea Zudov.LcLana (Nutt. ) S. (fiats Silver bladderpod Lepu Leptodactyton pungens (Toni. ) Rydb. Shrubby phlox Liin L.ithaapenmum £nc.Lsum Lehm. Gromwell Lupu* Lup.Lnu4 pus.iffus Pwush Rusty lupine Lyju Lygade.smLa juncea (Punch) D. Don. Rush skeletonplant Mavi MamLUan,i.a vLvLpana (Nutt. ) Haw. Ball cactus Melal* Meti,&o.tus alba Dean. in Lam. White sweetclover Meal* Mentzeti.a aeb.Lcaulis Dougt. ex Hook. Whitestem mentzelia Menu Mentzetia nuda( Punch) T. S G. Bractless stickleaf Migl M-Lhabilis glabna ((Vats. ) Stand. Four o' clock Mupu MuhLenbengia pungens Thwcben. Sandhill muhly Oela Oenothena £atLSotia (Rydb. ) Manz Evening primrose Oenu Oenotheluc nuttatti.L Sweet Evening primrose Opfr OpuntLa bnag.itLs (Nutt. ) Haw. Brittle pricklypear Ophu Opuntia humigusa Rag. Common pricklypear Orhy Onyzops.id hymenoLde.s (R. E S. ) RLcke& Indian ricegrass Pavi PanLcum vingatum L. Switchgrass Peal Penstemon a.&Ldus Nutt. White penstemon Pean Penhteman angua.tLbolius Nutt. ex Punch Narrowleaf penstemon Peco Peta.Coa.temon compactus (Spneng. ) Swezey Compact prairieclover Phho Phlox hoodt Rich. in Fnankl. Hoods phlox Phla Phyaatis 2anceotata M.Lchx. Ground cherry Plpu* Plantago puuhLL Roem. E Schutt. Wooly indianwheat Poar Poa an,Lda Vase Plains bluegrass Poer* Polygonum eteetum L. Erect knotweed Psdi Psonatea dLg.itata Nutt. Digitate scurfpea Psla Paow1ea £ancealata Punsh Lemon scurfpea Raco RatLb-ida coIumnLgena (Nutt. ) (Voo.t. S Stand/. Upright prairieconeflower Refl Redb.ie2dLa gkexuoaa (Thwth. ) Valley Blowout grass Ruve Rumex venoaws Punbh Veiny dock Sake* Satsota kati L. Russian thistle Sial* S.%symbru.um attis.simum L. Tumblemustart Soca SotLdago canadens.Ls L. Canada goldenrod Spai Sponobotus auw.Ldes ( Tonn. ) To-ut. Alkali sacaton Sper Sponobolub mint/Inc/Ails (Twuc. ) S. G/tay Sand dropseed Spco Sphaexatcea cocci,nea (Punbh) Rydb. Scarlet globemallow Stco Stipa comata T'uLn. S Rup2. Needleandthread Taga Taman Lx gate/Lea L. Salt cedar Taof Tanaxacum o66.icinaee W.Lgganb Common dandelion Thme The/ape/ma megapotamLcum (Spneng. ) Kuntze Perennial greenthread Thtr* The2e.spe/ma .t'uLsidum (Po.ih. ) Britt. Annual greenthread Trdu Tnagopogon dub.Lua Scop. Salsify Trmi* TAiptenoca2yx mLcvucnthwc (Tank.. ) Hook. Wingfruited sandverbena Troc Tnuadescantia occidentaL s (Britton) Smyth Prairie spiderwort Vebr Verbena bnacteata Lag. S Rook. Bigbract verbena Vinu V,Lola nut-tail-U. Punch Nuttall violet Yugl Yucca glauca Nutt. Small soapweed Zygr Zygadenus gnamLneua Rydb. Grassy deathcamas *Plants are annual or biennial . -95- -7124f b dig 'k ' a !! ;7. a t . ten, r Asa � <-- . . a ki.ffi =..f,: ..-Y1,1, i .4, 4,7 ° O ($ S. d o ¢ y R 6 4ygk . 1 ' • O C [ . � b y r`1 i r N N. p c N . '� S •' •J Fr A,. ., '^+• to 7 R A tr1 1:C x ,n '"-' c 41 — > - Lt- a-1 0 1-. -. to C1 .V 0 N _ � f _ iC t = a s � 4 N y cv 3 { a) l •_ .4 Y x� 1'� f -4,. " y' d �Y is er{.. $¢ $ ! m A � {tea —96— of the low-lying Valent Sand bordering the meadow and attains greatest cover and density on well-stabilized deep sands. The areas lacking sandsage constitute a small but distinctive sub-site because the shrub generally is most abundant on Valent Sand. Shrub stands generally are more consistent but less dense on Osgood Sand than on Valent Sand. 3. Wildlife a. General Movement Patterns of Mammals in the Area Big game animals (deer and antelope) and waterfowl have estab- lished movement patterns within the Weld and Morgan County areas. Most of the movements center around the South Platte Valley and around major water impoundments. Antelope, though few in number, occur in the reser- voir areas and are primarily winter residents. Deer occur throughout the yea53with numbers increasing in the winter and decreasing during the summer. i . Mammals a. Game Species Deer, both white-tailed and mule, are present in the Weld County area. Due to the scarcity of suitable habitat, however, deer popula- tions are low. Generally, the white-tailed species is dependent on the flood plain communities for food and cover throughout the year, while the mule deer uses the flood plain communities for food and cover more frequently during periods of inclement winter weather. There is pro- bably a greater abundance of white-tailed deer within the area than would be expected at other points along the river due to the transplanta- tion of a population of these animals from Oklahoma to areas of eastern Weld and Morgan counties. However, mule deer remain as the dominant species. Only a few deer and antelope are thought to inhabit the project site -- probably farther to the west near Box Elder Creek as more water and shelter are available. No herds have been observed . Cottontail rabbits are common throughout the area, but their popula- tion densities are greatest in the river bottom locations. The associa- tion of river bottom timber and brush with adjacent small grain and cornfields provides good production and survival cover. The cotton- tails are represented by the eastern (Syvilaqus floridanus) and the desert (S. audubonii ) cottontails. In addition, two species of jack- rabbit inhabit the area. These include the blacktailed (Lepus californicus) and the white-tailed (L. townsendii ). Fox squirrels are restricted to the flood plain and areas of deciduous trees. None were observed on the project site, although some exist in the neighboring towns of Keenesburg and Roggen. 33 Narrows Unit, III, 38. -97- b. Non-game Species and Furbearers Furbearing animals found along the South Platte River include beavers, minks, muskrats, raccoons, skunks, badgers, foxes, and weasels. However, none of the above species were seen in the proposed mining site. Coyotes are numerous within the area, and are thought to be the dominant carnivorous species on the flood plain. Apparently the flood plain area provides this species with abundant prey and carrion, includ- ing waterfowl species. c. Rodents Of all rodent species in the area, the deer mouse (Peromyscus maniculatus) is probably the most abundant. It is predominant in the vegetative communities present in the area. The northern grasshopper mouse (Onychomys leucogaster) if the most abundant rodent within the prairie communities and is probably the second most common species overall . In order of decreasing abundance, other species present include: voles (Microtus pennyslvanicus and M. ochrogaster), western harvest mice (Reithrodontomys megalotis), house mice (Mus musculus ), kangaroo rats (Dipodomys ordii ). Prairie dogs also occur in limited numbers. ii .. Birds a. General Area Species The Weld County and Morgan County areas are abundant in avian species. There are six major communities in this region mostly occuring in river bottoms. They are described as follows including the major species found in each community: Open Park - meadowlark, red-shafted flicker, magpie, and killdeer. Open Cottonwood - meadowlark, mourning dove, red-shafted flicker, and magpie. Closed Cottonwood - red-shafted flicker, mourning dove, meadow- lark, and blue jay. Mixed Willow-Cottonwood - mourning dove, house wren, killdeer, and red-shafted flicker. Willow - mallard, mourning dove, house wren, and red-shafted flier. During the summer months, the mourning dove, house wren, and red-shafted flicker are the major species with the mallard duck being the dominant species in the winter. Prairie - meadowlark, mourning dove, horned lark, and lark sparrow. -98- Of the listed community associations the Prairie community is the pre- dominant vegetative c omunity in the proposed mine site area. Waterfowl in large flocks use the South Platte River flood plains as a resting point during the winter months. These flocks feed in the irrigated and dryland cornfields just outside of the flood plain. Most of the waterfowl observed in the area are flushed from small ponds formed by old stream meanders or from the main river channel . Waterfowl are evenly distributed throughout the area with little variation noted between vegetative communities. Due to the lack of surface water and proper food, the waterfowl observed in the area were those in flight during their yearly migration. The flood plain communities provide excellent wintering habitat for the northern bald eagle, which probably relies heavily on carrion and wounded waterfowl for a food supply. Hawks and owls show little variation throughout the year, with a high of about 19 percent relative abundance in September and a low of about 6 percent in May. Three species within this grouping, the marsh hawk, sparrow hawk, and the red-tailed hawk are the .most frequently observed. The bobwhite quail and ringneck pheasant are present in the irrigated portions of the South Platte River Valley year-round, with populations peaking during the summer. These species reach a relative abundance of about 14 percent during the summer, decreasing to a low of about 2 percent during the spring. The pigeon and dove group is represented within the area by two species, the rock dove and the mourning dove. The mourning dove is an important seasonal species accounting for increases of doves noted during the summer months. The rock dove is present throughout the year. The jays, magpies, and crows are represented by the blackbilled magpie, blue jay, and common crow. The magpie and blue jay are present throughout the year, with the magpie being most common. The crow is not a common species within the area . The woodpecker group is represented within the area by the downy woodpecker and red-shafter flicker. These species are present year- round, with the flicker being the more abundant species. The blackbird and oriole group is most commonly represented by the meadowlark. Large populations of this species account for a high rela- tive abundance of this group within the area. Transient populations of seagulls have been observed in the mine site area. b. Endangered and Threatened Species The official list of endangered species was published in the Jan- uary 4, 1974, Federal Register (Volume 39, No. 3). The Endangered Species Act of 1973 (Public Law 93-205; 87 Stat. 884) provides a means -99- by which ecosystems upon which endangered or threatened species depend may be conserved. Section 7 of the act provides that all Federal agencies take care that their actions do not jeopardize the continued existence of such endangered or threatened species by destruction or modification of habitat that has been determined to be critical to such species. There are two such species that may occur near the project area, though no signs of these species have been found in the area. These species are the American peregrine falcon (Falco peregrinus anatum) , listed October 13, 1970, and December 2, 1970, and the black-footed ferret (Mustela nigripes) , listed in March 11 , 1967, and December 2, 1970. The Fish and Wildlife Service has published an unoffi54al list summarizing the Federal Register listings of January 4, 1974. The State of Colorado Division of Wildlife has listed the summer nesting resident white pelican and the greater sandhill crane as endan- gered in Colorado. There is a colony of white pelicans (Pelecanus erythrorhyncos) that inhabit an island in Riverside Reservoir (approxi- mately 12 miles northeast of the proposed mine site) in Weld County. This breeding colony, which totaled 800 individuals during 1974, remains on the island from March or April until November. Since this is the only pelican colony in Colorado, the Division of Wildlife is interested in propagating the species. An attempt has been made to establish an additional colony through transplants of fledglings to a recentig con- structed island in Lower Latham Reservoir southeast of Greeley. Northern bald eagles were also observed within the Narrows Project area and receive Federal protection through the Bald Eagle Act, as amended (16 U.S.C. 668-668d) . 4. Reptiles and Amphibians Reptile and amphibian species most common to the site are listed by vegetative community as follows: Prairie - bull snake, western box turtle, plains spadefoot toad, hognose snake, lesser earless lizard, short-horned lizard, and six-lined racerunner lizard. Open Park - racer, red-sided garter snake, plains garter snake, and plains spadefoot toad. Open Cottonwood - bull snake, six-lined racerunner lizard, Woodhouse's toad, and racer. Closed Cottonwood - six-lined racerunner lizard, red-sided garter snake, and bull snake. 34 United States List of Endangered Fauna, Fish and Wildlife Service (Washington 1974), 22, as cited in Narrows Unit. 35 Bartell Nyberg, "Yes, Pelicans in Colorado", Empire Magazine (Denver Post supplement) 16 March 1975, 28-32, as cited in Narrows Unit. -100- Mixed Willow-Cottonwood - red-sided garter snake, plains garter snake, Woodhouse's toad, plains spadefoot toad , racer, bull snake, and six-lined racerunner lizard. 5. Insects and Vectors Nine orders of insects occupy the Weld and Morgan County area. These include: Lepidoptera (butterflies and moths) , Diptera (flies), Hemiptera (true bugs ), Homoptera (cicadas, leafhoppers, treehoppers), Coleoptera (beetles), Orthoptera (grasshoppers and crickets) , Psocoptera (lice), Dermaptera (earwigs), and Hymenoptera (ants, wasps, and bees). The greatest number of insects in the area seem to be representative of the Orthoptera, Coleoptera, and Diptera. Many beetles and grasshoppers are found in the prairie. Most of the Diptera are found in areas of dense, woody, and herbaceous vegeta- tion. Mosquitoes are particularly abundant around areas containing willows, such as pure willow communities. -101- I . Aquatic Ecology The South Platte River Valley north of the proposed mine site offers very little in the way of desirable fish. %cording to a Colorado Department of Game, Fish and Parks study, the total per- centage composition of fish in the river is: desirable fish - 3.3 percent; undersirable fish - 44 percent; and forage fish - 52.7 percent. Perch were the dominant desirable fish collected, sucker and carp were the dominant undesirable species,31nd shiners (Notropis) and creek chub were the forage fishes collected. There are five major tributaries entering the South Platte in Weld and Morgan Counties. All five streams, the Crow, the Lost, the Box Elder Creek, the Kiowa and the Bijou, are classifed as intermittent and have very little fishery value. Each contributes very little to the growth and perpetuation of fish in the South Platte. The only major water impoundments in the vicinity of the project are Riverside, Milton, Empire, Lower Latham and Jackson reservoirs in Morgan County. Only Jackson is open to the public for fishing. The fishing accessibility of the four privately-controlled reservoirs is unknown. There are no lakes or other water impoundments on the project site at this time, except for small stock watering troughs around wells. 36 Don T. Weber, Narrows Pre-Impoundment Investigation, Colorado Department of Game, Fish and Parks (Denver 1975 and 1976) as cited in Narrows Unit. 37 Narrows Unit, III, 71 . -102- III. PROPOSED MINE PLAN A. Facilities The main facilities at the proposed mine site will consist of the following: 1 . Office, shop, warehouse, bathhouse complex 2. Equipment parking lot 3. Coal processing plant and truck loadout 4. Drainage ditches and sedimentation basins for runoff water 5. Pump system and settling basins for pit water 6. Domestic waste treatment facility 7. Main access road to the mine site 8. Electrical distribution system 9. Potable water system 10. Explosives storage -103- B. Mining Plan and Reclamation Plan 1 . Coal Processing Operation Initially either a truck and power shovel or one electrically driven 18-yard construction dragline will be used for overburden removal . Between the 5th and 10th years of operation a second 18-yard dragline may be built and put into operation. Each proposed dragline is planned to operate 24 hours, 6 days per week, 50 weeks per year, and will remove 4.4 million bankyards of overburden. Figure III-1 shows an artist's conception of the area mining method with dragline. The exposed coal will be loaded into belly dump trucks with a diesel powered hydraulic backhoe. The backhoe is expected to operate 8 hours per day, 5 days per week. The coal will then be transported by belly dump trucks to the coal processing plant where the coal will be dumped into a hopper. The coal will travel from the hopper to a stamler feeder - crusher which will reduce the coal into 7" pieces. An inclined vibratory screen will remove any 12" mined coal and chute it onto a belt conveyor which will transport the coal to the top of a covered conical coal storage pile. Coal pieces larger than 1'" will be chuted to a single-roll secondary crusher where it will be crushed to 11/2" and conveyed to the top of the covered conical coal storage pile. From the storage pile the coal will be discharged onto a coal ladder and into the live conical pile (20,000 + 1 tons). Two feeders under the pile will feed the coal as needed onto a belt conveyor that supplies coal to the truck loadout. A sample automatically will be drawn before going to a 28 + 1 ton weight bin. The coal will be discharged by gravity onto trucks for transportation to Golden. At a later date Coors Industries will require the installation of a screening and storage facility for sized 3/4" x 3/8" coal for Coors Boilers #1 , #2 and #3. The rates of overburden and coal mining operations are based on the anticipated coal consumption schedule in the Table III-1 . 2. Mining Plan Geology - Coors Industries initiated a coal exploration program in the Keenesburg-Roggen area in May, 1976. One area was found where the top seam (No. 7) of the Laramie Coal Group increased in thickness to be feasibly mined. Subsequent coal exploration programs have been conducted to define the mining area and the quality of the coal . None of the underlying six coal seams of the Laramie Coal Group are of mineable thickness in the mining area. The average proximate analysis on an as received basis of this mineable coal seam is as follows: Moisture. 29.38% Ash 8.00% Volatile Matter 29.55% Fixed Carbon 33.08% B.T.U. 8020 Sulfur .37% Trace elements in the coal seam do not occur in objectionable quantities. Maps showing the Bottom of Coal Contours, Isopach of Coal Thickness, and Isopach of Overburden Thickness verify the coal deposit. -104- Mining Method - Because this coal seam is close to the surface, Coors Industries determined that the most feasible method of mining would be surface methods. A surface coal mine would provide a 90+ percent recovery of this valuable resource. Underground mining of the area would recover less than 50 percent of the coal and the surface of the mined out area would be packed--marked with depressions from the underground operations. The depressions would render the mining area useless for grazing after mining is completed. Mining Plan Site Preparation - Enclosed is a map titled, "Surface Features Map" which provides information on the existing surface features, holes drilled for coal exploration, and an outline of the mining boundary. Initial construction at the site will consist of access road construc- tion; excavating and construction of a coal processing, storage, and loadout complex; construction of an electrical distribution system; completion of a potable water system; and construction of a shop-office complex. Top soil will be removed in the affected areas and will be stored for future reclamation use. Weld County Road No. 59 will be extended 4.2 miles to the mining site. This extension will be constructed to recommendations and standards established by the Weld County Department of Engineering. Upgrading of 2.5 miles of existing County road will be necessary to withstand the truck traffic hauling coal to Golden. Electrical power will be purchased from Home Light and Power Company. An extension of the existing system south of the mining area to the coal processing plant will be constructed starting in August, 1979. A drainage and sedimentation basin system will be constructed to guarantee that runoff waters from the disturbed areas will be collected and clarified before they are released to the surface drainage system. Mining Phase - Initial mining may occur in the small triangular block in the northeast corner of Prt A as shown on the Mining Plan exhibit. This triangular area will be excavated with dozens and scrapers and will be mined until the dragline is constructed. Coal from the initial mining may be processed by a temporary crushing facility until the permanent plant is constructed . Dragline Operations - Removing the overburden will also begin in Pit A and mining will be restricted to Pit A during the first year while natural gas lines owned by Coors are relocated out of Pit B area. In second year of operations alternate dragline cuts will be excavates in Pits A and B. During the actual mining operations the top soil will be removed and placed in storage piles or redistributed on reclaimed spoil areas. The A horizon may be stored separately from the B horizon or mixed together depending upon the conclusions of the study now in progress by Colorado State University. Also the B horizon may be distributed by the dragline on the reclaimed spoil piles. The remainder of the 20 feet of blow sand will be dozed into the pit excavation. The long-term top soil storage piles will be sloped and seeded to limit erosion. -105- The overburden from the first cut in Pit A will be placed upon the existing surface to the north of the cut. These spoil piles will be resloped to an acceptable slope which will blend with the turnover cuts or the succeeding cuts. The overburden will be drilled and blasted when it is deemed necessary. Vertical holes will be drilled at a predetermined spacing into the shale overburden. The holes will be charged with an ammonia nitrate fuel oil mixture and cast primers. The holes will be delay detonated with prima cord and millisecond delays. The holes will be loaded and detonated during daylight hours and a schedule of detonation will be provided . The dragline will remove all of the overburden above the top of the coal and a dozer will aid the dragline. Initial dragline operations will be conducted six days per week twenty-four hours per day and during later years the dragline operations will be extended to seven days a week, fifty weeks a year. The dragline will be electrically driven. Dragline cuts will be approximately 100 feet wide and 3,200 feet long . The surface sands will be cut at a 2:1 slope and the shale overburden will be cut to a 1/2:1 or flatter slope. A second dragline will be required when the overburden thickens. The exposed coal will be loaded into two belly dump trucks with a hydraulic backhoe. The backhoe will dig and load the coal without blasting, if possible, but on occasions the coal may have to be loosened with explosives. Coal loading and hauling operations will be conducted five days a week, eight hours per day, fifty weeks per year. A motor grader will maintain the haul roads and a water truck will haul pit water to allay and control haul road dust. A twin engine scraper will build the haul roads as required. The trucks will dump the coal into a bin and the coal will be processed, stored , and loaded out for shipment to Golden by trucks. These trucks will operate twenty-four hours per day seven days a week. The average coal thickness is 6.86 feet and thickness varies from five feet to 8.1 feet. The overburden thickness varies from 40 to 160 feet. At full production the mining operations will disturb and reclaim 40 to 55 acres per year. A total of 1 ,503 acres are in the mining area. Recoverable coal reserves are estimated to be 11 .5 to 12 million tons. The mine life is 20 to 25 years. As now planned the construction phase will extend over a period of 270 days and will employ up to 200 people. Construction phase will begin after mine permitting or about August 1 , 1979. The initial production of coal will occur in the second quarter of 1980. Employment in the mining operations will vary from 35 to 40 permanent employees. -106- et Ill.J-�1 • ,4r, 1S • r. .,' ... 1. ., ' ;j I WI ` l:1111 lI1IiiIII Il.i� �� 'I • .' r' ♦ , �' .'• • ryre lltttRRRfff��rr 1111 h,r��l ,I it�1 /,. Q •I ,, r Q �(1.e..,. �'^�'. i I I I,IIII Il,il'�I I 1 1 +l, i� 1 L.... ... . , , ..... ..:• I9� . f'- 0 , (.r. —r , i•re r•r A 'VIII II. II ,i� ,IJ•�. 1 c . '' ,,I r • I i IlIli'I Ii , II It,l(( P';. — , rr • ' � . I hi 11' i III II'I r . r• I, III III , 4, r ,b .I W ;•�._ � .F,., 'II!IIiiI�':I�, ,�, 1 i id 1,1 ; r T p� J f.• ,Kr • Q '=r , ,[ \I 1 re ri- �'.� 1 I O ( - \ i I, it illii . I I' C 1 i ' �' �� f1'i ' z\l / 1 1 I i ti liti I t •k - , \ . � :� it.- I cc :�a) , • ' 3 ! I! Ill I \\ \ ,\( or I \ ( fl :illo , re: C 7, . �' �I z �I III �1 ( I�I N �y f , I ,'. I I� I L - ` , // S I (I + .,, 1. „ I X11,1 ./.\\,\ `r\ 1 \ !il \ \ *;..\ ,j 1 ,;III �I III ! �I�1'I 1 in. frt ' : I.I. , 1 Ir ' 1 )1 , ' ', 0 �I Q 1' III nII ` IO 1` Q., I I D ,II, [ II1I'I'! III I r II '' a 1\I V �; ' , 1 1 ; .' zA • �' aQ�I 1 • �'Il,lr...v 1 . ` '' r, g. �; ' '' z •' ' } W ?I i s ► I I II • n J3•.r �rtc•��l �� •s"� 1�'' 3E )f ; �3f.� Syr �. ' �, I I! ,I `: I 1111 '4:C�tf:•.e I VI FI 'a.'),_•. .:.✓s.,>..�� : ,3 -r,�...;.. ..r.�} t< � , l. .�ir 1�I11 ,. I .I TABLE III-1 ANTICIPATED COAL CONSUMPTION YEAR COAL CONSUMPTION (IN TONS)* 1980 361 ,000 1981 450,000 1982 487,000 1983 519,000 1984 548,000 1985 578,000 1986 631 ,000 1986 & Forward 649,000 * These figures are dependent upon Coors projected expansion of beer production at the projected schedule. -108- 3. Reclamation Plan In an attempt to develop a workable and effective Reclamation Plan the Adolph Coors Company contracted with the Department of Agromony at the Colorado State University to inventory soils and vegetation and carry out revegetation research during 1978 on the proposed mine site. These studies resulted in several recommendations being made which are incorporated into the Coors Reclamation Plan . The Topographic features of the proposed mine site consist of low rolling sand hills ona semi-arid plain. The surface elevation decreases from 4870 to 4800 in a north eastery direction as may be noted on the enclosed topographic map. Present surface drainage that may exist is north eastery toward Ennis Draw. Most of the area is now covered with about 20 feet of wind deposited sand. This sand lies immediatary above the beaded clay shale of the Laramie formation. The soil being -very sandy is susceptable to wind erosion after it has been disturbed. Two soil types present on the property which may be used for reclamation are the Osgood Series and Valent Series. About 30 inches of Osgood and 4 to 6 inches of Valent may be available for reclamation purposes. Chemical analyses were conducted on the soil and no adverse characteristics were found that would prevent it from being used in reclamation . As miningadvances all of the "A" Horizon topsoil will be stored and up to 21/2 feet of "B" Horizon soil will be stored. The excess "B" Horizon sand will be dozed onto the pit slope to be later placed on the spoil piles by the dragline. Reclamation will follow the active pit as close as practical . The spoil piles will be leveled so asto present a surface contour similar to the pre-mining surface, but due to the swelling of the disturbed material , it will be at a slightly elevated position. Slopes on the reclaimed surface will not exceed 2:1 . Topsoil and sand will be placed on the leveled spoils to a pre- determined death by use of either the dragline or scrapen. It has been recommended that the clay shale type spoil be covered with about three feet of sand with the top one foot consisting of the existing topsoil . A further recommendation is to use manure at a rate of thirty tons per acre dry weight. The manure is to be mulched into the topsoil to prepare the soil for seeding and help reduce erosion. When applying the manure it should be done immediately after topsoil placement so the seed may be drilled into and through the manure mulch. Seeding is planned once each year in the spring on the newly reclaimed spoils. Sprinkler irrigation is planned to start immediately after seeding. The irrigation rate will be at about nine inches during a three month period through the first growing season. The seed mixture as determined from the results of the test plots is as follows: Prairie Sandreed at 10 Pls per sq. ft. Sand Bluestein at 4 Pls per sq. ft. -109- Blue Grama at 4 Pls per sq. ft. Western Wheatgrass at 4 Pls per sq. ft. Sand Dropseed at 1 Pls per sq. ft. Indian Ricegrass at 1 Pls per sq. ft. Sideoats Grama at 1 Pls per sq. ft. Little Bluestem at 1 Pls per sq. ft. After seeding the use of a certain amount of broadclear weed killer is suggested to insure a good stand of warm weather grasses. Grazing will have to be well managed to prevent overgrazing the revegetated surface. Surface runoff appears to be minimal on the mine site as no erosional features are noticeable. The sandy of nature of the soil allows the surface water to penetrate radily. However, to lessen the possibility of pollution due to runoff, the construction and operating area as well as the topsoil storage piles will be protected by a series of drainage ditches and sedimentation basins. Earth dams or water bars will be constructed if it is deemed necessary to control runoff and erosion. The coal face exposed in the final P.T. will be covered with earth to keep any acid forming materials that may be present from polluting the drainage system. Upon completion of the mining operation all refuse will be disposed of and the site rehabilitated to prevent water, or visual pollution. The disturbed land will be removed from normal use during the mining operation. It may be possible to have ,the land returned to limited grazing after the second growing season following reclamation. The reclaimed land should be available for full grazing in the fifth year after reclamation. During the period of early grazing the reclaimed area must be well managed to protect it from overgrazing. Blasting Impact The impact due to blasting operation at the mine site is expected to be minimal . During mining if it is found that all overburden must be shot it would require shooting the overburden according to a published schedule. Each hole being charged with an ammonia nitrate fuel oil mixture depending on the depth of the hole and type of overburden. When the shot is detonated a delay pattern will be used instead of an instan- taneous shot. A delay pattern allows the holes to essentially explode one at a time in a closely spaced series instead of all at once. The use of delays in the shot tends to reduce vibration which is due to ground movement. Some dust will be generated upon detonation but is expected to dissipate rapidly. The blast hole drill will be equipped with a dust collection system so the dust generated by drilling should also be minimal . -110- The inhabited structure nearest the mining site is located 1.9 miles north of th proposed operation. This is a safe distance according to both federal and state regulations. All blasting, blasting materials, explosive handling as well as explosive storage will be according to the federal and state laws and regulations governing explosive use as well as the recommendations of explosive manufacturers. Cattle grazing near the blasting site will be started by the first few shots but usually become accustomed to the noise after a few shots. At the time it is planned to use a type of ammonium nitrate as the blasting agent, cast primers and prima cord with primacord delays. -111- C. Pollution Control 1 . Water One water well tapping the Laramie-Fox Hills Aquifer will be used to supply -water for the bathhouse-office complex. A storage tank anc distribution system will be designed to provide fire protection. A second well in the aquifer may be required to supply irrigation water to the vegetated lands. The pit water from the coal and overburden will be allowed to collect by gravity flow in the pit depressions or sumps. The collected water will then be pumped to a two-compartment settling basin located on natural ground south of the shop-office complex. The first compartment will act as settling basin with the clear water being stored in the second compartment. Due to the unacceptability of this water for irriga- tion or discharge into the natural drainage system without treatment, the water will be used for fugitive dust control on haul roads and where needed. The rate of water inflow from both sides of the opening box cut is estimated to be 70 gallons per minute from a pit 7,500 feet long. This flow would eventually stabilize to a rate of 5.4 acre feet per year. However, these figures are currently being revised downward by the CSU hydrological research team. Even with the theoretical inflow rate of 5.4 acre feet per year, the inflow would be substantially reduced by evaporation and absorption in the pit floor. During warm weather months the flow may be reduced to extremely low levels or to no flow situa- tions. 2. Domestic Waste Treatments A domestic waste treatment facility will be engineered to handle wastes from the washhouse and restroom facilities. This facility is designated as a package unit, and the water may be used for either dust control or irrigation. 3. Air Pollution Abatement Cyclone dust collectors will be used in the following areas. a) Truck dump, coal crushing, and coal screening areas. b) Belt conveyor discharge onto the conical storage pile. c) Coal recovery tunnel , weigh bin and truck loading areas. Fugitive dust from the haul roads will be controlled by the use of water from the pit settling basins, and, if necessary, chemical additives such as Coherex may be used for additional control . Haul road traffic in the pit area will consist of two 35 ton belly dump trucks operating 5 days per week, 8 hours per day. -112- IV. IMPACTS OF SURFACE MINING OF WELD COUNTY AREA IV . IMPACTS OF SURFACE MINING OF WELD COUNTY AREA A. Impacts of Socio-economics 1 . General The development of coal resources in Weld County will produce only slight changes in social and economic patterns already established in the communities. The development of coal is not new to the Weld County area. Historically, the towns of Erie, Dacono, Firestone and Frederick developed as coal towns but now remain as farm communities, suburbs of the faster growing cities of Greeley and Denver. An objective of this report is to predict the socio-economic impacts of coal development in and around the proposed mine site. Coors Industries in its venture into energy development is preceded in the Keenesburg area by energy com- panies: Amoco, Chevron and Standard Oil . These companies have already impacted the Keenesburg-Fort Lupton community by their renewed explora- tion for oil and natural gas. Historically, Weld County's economy has been dominated by agriculturally- oriented activities. Agriculture continues to play an important role in the local economy, and Weld County leads the state and ranks among national leaders in livestock and crop production. Cattle dominates livestock production activities, including both cattle on feed and cattle and calves in the field. As of January 1977 Weld County ranchers accounted for 615,000 cattle and calves, with an additional 374,000 cattle on feed. The total value of crop production in the county more than doubled during the first four years of the 1970's, and while total value has declined during recent years, crop production is still young. During recent years corn production has accounted for about one-half of the total value of crop production. Preliminary estimates indicate that the total value of Weld County crop production in 1977 will reach $110.2 million. Corn production value will exceed $50 million. During recent years the economy has grown and diversified as a result of manufacturing and commercial developments. Industries in Greeley today manufacture a wide variety of products including sugar, meat products, mobie homes, chemicals, potato chips, fishing equipment and work clothing. 2. Demography The population of Weld County has grown steadily over recent years, increasing from approximately 90,000 people in 1970 to about 140,000 people at the present time. Since 1970 the City of Greeley has grown from about 39,000 people to a current population of 60,200. Greeley and Weld County are located in the northern Front Range region of Colorado, one of the fastest growing areas of the entire state. During the 1960 to 1970 decade, Weld County grew at an annual 38 Weld County Facts, Greeley Chamber of Commerce (Greeley 1978) . -115- rate of just over two percent. From 1970 to 1980 the county is expected to grow at an annual rate of 4.3 percent. During the same decade Greeley is forecasted to grow by 5.4 percent annually. The residents of Greeley and Weld County are generally younger than those of the state as a whole. In 1970 the median age of Greeley residents was under 24 years, while the median age of Colorado residents was over 26 years. The education level of Weld County and Greeley residents is comparable to those of other Colorado residents. The per capita personal income levels of Weld County residents have grown substantially during the 1970's. From 1970 to 1975 per capital personal incomes increased at an annual rate of 12.2 percent, a rate well above that of general inflation . The historical as well as the projected populations of cities and towns in Weld County from 1960 to 1985 are represented in Table IV-1 . The most striking indication of the projected population table is that 90 percent of the cities and towns in Weld County show an increase for the next 10 years. This increase will insure a continued supply of persons for the labor force. As other energy related projects move into the area, more growth will occur. The Keenesburg site would most likely remove only a small amount of the labor force while increasing the economy around Keenesburg and Weld County in general . 3. Employment Historically the Weld County area has experienced a continual growth of the available labor force since 1970. At present the work force is approximately 59,000 people. The percentage of unemployed is 3.9 as compared to the national average of 4.3 percent. As Table IV-2 shows, the labor force has steadily increased from 1970 through 1977 with unemployment remaining relatively constant. This information indicates a slight absence of qualified people in a labor pool readily available for employment. Therefore, a majority of the workers must be bid away from other jobs (consequently at higher wages) or recruited from outside areas. If workers are taken from non-energy related posi- tions (service-oriented jobs) , the goods and services available in the area may be reduced. This would only be a temporary loss because these jobs would be filled by other workers trained for the positions or by people suited for the jobs vacated moving into the area. Table IV-3 is a list of selected employers in Weld County and their present employment. The information shows there are substantial qualified individuals in Weld County to support the development proposed by Coors. 4. Economics and Income Weld County's economy has been dominated by agriculturally-oriented activities. At one time Weld County was one of the richest agricultural counties in Colorado and the nation. It still ranks high and remains the leader in the state. -116- During recent years, the economy has grown and diversified as a result of manufacturing and commercial developments. Industries in Greeley today manufacture a wide variety of products from food products to fishing equipment and work clothes. As shown in Table IV-4 retail sales activity in the county as a whole increased by 12.7 percent from 1970 to 1977. The proposed coal mine would contribute to the income of the general population through additional funding by taxation of capital investments and improvements to the county. As previously indicated, the total number of employees at the mine would be approximately 35. (This excludes personnel for reclamation. ) The assumed payroll for this operation would be approaching $765,000 per year or about $21 ,800 per person. The following is a breakdown of the personnel required and their approximate accumulative wages: 1979 ESTIMATED PAYROLL 20 Hourly production employees $420,000 5 Hourly maintenance employees 97,000 2 Watchman and janitors 20,000 8 Supervisory employees 228,000 35 $765,000 Along with the increased wages from the mine, the tax benefits to local communities in the county and the state from this project are extensive. Initially, equipment and improvements to the property will approach $9,562,000. Both the state and other taxing authorities will receive benefit from the materials purchased for the improvements and the equipment sales. Property tax benefits can be found in increased value of the property because of the presence of the improvements. Mineral severance taxes, both state and Federal , will also be of substantial benefit. Sales tax for other routine supplies will be collected by taxing authorities in the area. The Federal Black Lung Program will receive funds from each ton of coal loaded. Payments into the Black Lung Fund will aid recipients. The Ton Mile Tax paid on transporting the coal from the mine to Golden will provide funds to build and maintain the required roads. Employees working at the facility will be paying income tax to the various taxing authorities. Their increased purchasing power will also benefit these areas due to increased sales and, therefore, increased collection of sales tax. Purchases of real property by these employees will increase the real property tax base. In conclusion, tax benefits through sales, income and property taxes will be extensive. The state, county and local communities will all benefit from increases in the value of taxable property plus increases in the actual property tax base. Impacts caused by the mining operation could be funded by severance taxes. -117- 5. Housing Due to the proposed mine and the additional employment required for operation, some workers may want to relocate closer to the mine itself (probably in Keenesburg) . During the lifetime of the mine the employee number will not fluctuate. If employees wish to relocate near closer towns, there will be a slight increase in the housing prices and in the demand for adequate housing. Some inadequate housing may develop due to the short supply. This would be of a temporary nature. Land and space is available in Keenesburg for additional housing. Between 1974 and 1977 the town of Kee2sburg was issued 27 new building permits for residential housing. Recently, new projects have been approved to expand and improve the Keenesburg water and waste facilities. These projects will insure adequate water and treatment facilities in the future. Other towns will be affected to a lesser degree. 6. Education An estimated 50 students would relocate with their families in school districts in the vicinity of the project, such as Keenesburg or Kersey. (This figure is based on the possibility of 20 families relocating in and around the areas with 2.5 children per family. The actual number of school -age children may be considerably less. ) The towns near the proposed coal mine have not experienced a large population surge, and classrooms are not completely full in some grades. The school districts should easily handle the increased number of pupils. There may be a slight impact on the children themselves occurring because of the movement into a different area or school district. Some children conceivably may experience confusion, frustration and even emotional problems from such a move; however, all such problems could be overcome. 39 Housing Authorized by Building Permits, U.S. Department of Commerce, C40 series, selected issues. -118- B . Impacts on Land Use 1 . General The proposed mining project requires a total of 1 ,503 acres of land. All lands are within Weld County and are currently classed as rangeland (See Map #4) used for grazing of livestock. Some of the area exhibits characteristics associated with overgrazing, specifically in the northwest section (section 26) of the proposed mine site. There are no important farmlands within the area as defined in the Federal Register (31 January 1978) report on final rules for the implementation of a national program for inventorying prime and unique farmland . 2. Projected Land Use Destruction of vegetation at the mine site will reduce the amount of grazing acreage available for wildlife and domestic livestock during mining- operations. With proper reclamation management to establish ground cover to stabilize the disturbed topsoil and a "long term gr4tzing management program, most of the seeded vegetation should persist. " The area should therefore -- with proper management -- be in a condition equal to or better than existing conditions prior to mining operations. 3. Transportation Impacts on transportation will primarily consist of the improvement and construction of roads necessary for truck transportation of coal from the mine site to the nearest highway (Interstate 76) for delivery to Golden. The design of the main access road will be engineered to Weld County standards. 4. Recreation Since there are limited recreational facilities on the proposed site or immediate vicinity, impacts on recreation in the general area are not anticipated. 40 W.A. Berg, Soil and Vegetation Inventory. -119- C. Impacts on Archaeological and Historical Sites As stated in section II Part D, there are no recorded historical sites and no evidence of any cultural resource that could be of signifi- cance at the proposed mining site. However, if any sites or artifacts are uncovered during mining, the Colorado State Archaeologist will be notified, and the find will be protected until an interpretation can be rendered. -120- D. Impacts on Hydrology and Water Quality Mining of the coal seam by removing the overburden in strips and backfilling with a mixture of geologic materials in the adjacent pit will disrupt the natural sequence of strata from the bottom of the coal seam to the surface. Whether or not the aquifers were originally confined or unconfined, the exposure of the aquifers in the pit will cause them to become uncon- fined in the vicinity of the pit, and should therefore result in a predicted inflow of water at 5.4 acre feet per year. The water resources in the mining area that will be affected by mining operations are those in the coal seam, Laramie formation overburden, blow sand and stream deposits associated with Ennis Draw. The Laramie-Fox Hills formation, the most important aquifer in the area, is 200 feet below the maximum depth of mining and will not be affected. The CSU study shows that the "hydraulic budget of the area and that water levels in the mined area and in EnniilDraw will- recover to their original level following the end of mining". Surface runoff is essentially nonexistent in the proposed mining area under present conditions and is not expected to change -- provided that approximately three feet of A and B Soil Zones are placed over the spoil in the reclamation phase. The drainage of the reclaimed spoil area will be designed to insure that any runoff waters would be collected in sedimentation basins before they are released to natural drainage. Composite samples of the overburden and existing overburden waters show that no further degradation of water quality due to the overburden water passing through the spoils would occur. The overburden water is of poor quality, and its only probable use is in fugitive dust control . Due to the higher quality of water in Ennis Draw great care will have to be taken to keep hydraulic communication from occurring between pit waters and those in Ennis Draw. If the waters in Ennis Draw channel are substantially disturbed by mining operations, steps will be taken to reduce the impact. 41 McWhorter. -121- E. Impacts on Air Quality 1 . Present Air Quality The fugitive dust condition is an existing problem on the plains in the vicinity of the Keenesburg project. The origin of the windblown sand and soil is exposed plowed field, overgrazed rangeland, and dis- turbed areas without vegetation primarily west of Milton Reservoir. The fugitive dust problem will continue to exist with or without this pro- ject, and undoubtedly it will occasionally exceed the Environmental Protection Agency's air quality standards. The prevailing westerlies clear the Front Range area and disperse pollutants. Under such circumstances pollutants may provide a more or less continuous dosage to occupants of an extended area downwind of the mine site, resulting in the slow concentration of substances, such as lead, or -a continuum of low grade "physiological insults" that may eventually overpower "physiological defenses. " However, he site is sparsely populated; the only "downwind" towns are Keenesburg and Roggen. The area being arid, the population of these towns would only be sub- jected to slightly higher concentrations of fugitive dust--most of which would be settleable particulates. The Keenesburg mine site is in a nonattainable area for suspended particulates as defined by the Colorado Air Pollution Control Division . As previously described, the area immediately surrounding the project is dry grass prairies excluded from the Central Water Conser- vancy District due to its "potential for water development being poor. -T No farming or agricultural use potential exists in this area (other than grazing of cattle) except to the north around Kersey and to the south of Keenesburg in the Prospect Valley. The air quality in Weld County is generally good to very good based on suspended particulate measurements from data received by the Colorado Department of Health, Air Pollution Control Division. Table IV-5 compares Federal and Colorado Air Quality Standards for Denver, Weld County and Greeley. To supplement the data, Coors established its own high volume air sampler at the site (Figure IV-1 ). Table IV-6 shows the sampler data since its operation began on May 24, 1978. Although most of the standards for particulates were exceeded at the Denver locations, Greeley had low concentrations. The Keenesburg locale was relatively low--indicating low pollutants levels from sources other than natural background. 2. Effects of Mining Construction operations to develop support facilities will proauce dust and localized emissions from construction equipment and materials processing. The amount of exhaust and dust contributed to the atmosphere 42 L.A. Chambers, "Classifications and Extent of Air Pollution Problems," Air Pollution, (New York 1968) I , 21 , as cited in Narrows Unit. 43 Telephone conservation with the Director of the Weld County Conservation District (6 June 1978). -122- will vary from year to year as the coal is extracted. Exhaust emissions and dust can be offensive to people near the activity because the odor and appearance contrast with the surrounding aesthetics. Mining activity is usually constant in nature as the extraction of the coal becomes routine and of short duration ranging to a few years. After construction is complete, activity will decrease and then remain constant as the extraction continues. Due to the nature of mining itself, there are many sources of fugitive dust. Coors Industries plans to minimize dust by the use of dust-collecting systems at the transfer points in the processing plant and at the spreading manure, reclamation and planting sites, and by the use of water or surface of access routes. Topsoil stockpiles will be designed to minimize material loss and will be planted when necessary to reduce losses. Diesel equipment will be adjusted and maintained to the manufacturers' specified standards to reduce air pollutants. Surface mining and related activities will unavoidably reduce air quality in the area. Vegetation removal and soil disruption during construction of the support facilities and access roads will increase the susceptibility of the soil to wind erosion. During actual mining operations fugitive dust will be released from coal and overburden handling near the mining faces as well as from haulage roads, truck loading, storage piles and other exposed soils. Electrically driven equipment will be used, when possible, to reduce emissions. The most significant secondary effect on air quality will result from travel to and from the site by coal -hauling vehicles. Common pro- ducts of internal combustion engines include water, carbon dioxide, carbon monoxide, nitrogen oxides, and various organic gases, notably ethylene. Carbon monoxide is a toxin, but extremely heavy traffic is necessary for it to rch hazardous levels, i.e. , 100 parts per million for most individuals. Nitrogen oxides (nitric oxides and nitrogen dioxide) are only formed in a highly efficient combusion process ; both are toxic b can further react into photochemical oxidants which reduce visibility. Plants, the basic components of an ecosystem, are vulnerable to much lower levels of air pollution than animals and to a greater variety of pollutants. Ethylene is a potent phototoxicant, i .e. , plant-damaging agent. Ethylene could be a factor in plant injury in the environs of mining activity if extremely heavy vehicle use should be concentrated in 44 Air Conservation, AAAS Publication No. 80, Air Conservation Commission (Washington 1965) as cited in Narrows Unit. 45 Air Conservation. 46 Robert L. Smith, The Ecology of Man: An Ecosystem Approach (New York 1972) as cited in Narrows Unit. 47 Air Conservation. -123- F. Impacts on Wildlife Any surface mining project, such as the one proposed by Coors Industries, will have some unavoidable effect on any wildlife which occurs in the area. (Since no water impoundments are on the Keenesburg boundary, comments are directed strictly to terrestrial fauna. ) 1 . General On-Site Impacts The mining activity will remove the resident populations of vege- tation and community mammals. Little disturbance of the general topo- graphic features will occur. Perhaps as many as 50 species of mammals, birds, and reptiles will be affected by mining on the site. Many of the ground and burrowing animals will be killed. Larger mammals and birds will be displaced from home territories as the mine face advances across the site (see Section III). These impacts are unavoidable, but with reclamation and proper management most of the communities can be replaced , and impact can be minimized. It will be impossible to reconstruct the ecological plant and animal communities that were present prior to mining to the exact or nearly exact state before mining. Communities will be able to re-establish in the area after reclamation. 2. General Off-Site Impacts Developments off-site, such as housing developments, new roads into the area, increased people living and going through the site, will all affect the wildlife in the area. Most disruption of the wildlife community would be from actual mining operations. Mining causes displacement of animals by human presence, human activity, dust and air quality changes, and noise. Many animals and birds will relocate in neighboring communities if food and habitat are available. This would promote competition for food and territory which would start other reactions and increase mortalities until a stabilization occurs. Some mammals, birds and reptiles could co-exist during the mining operation and move to different areas of the site as the face advances. As reclamation takes place some animals could move readily back into the area, re-establishing territory and habitat. Most of the conditions described above have already occurred in the area with the renewed interest of oil and gas exploration by major companies. The construction of pipelines, derrick platform grading, and general traffic have caused major disruption in the general area with no major consequence to the wildlife. 3. Expected Impacts on Vertebrate Groups Rodents and some reptiles will either be killed or displaced. Most species, such as kangaroo mice and field mice, abundant and widely distributed, have high reproductive potentials. The impact on these species will probably be short-term, due to their adaptability to re- inhabitat other areas. However, other mammals such as the pocket gopher, are widely dispersed and live underground , limiting their movements -124- from one place to another. The impact on these species will probably be greater because their rates of establishment are slow. All rabbits will be displaced due to the mining activity. The jackrabbits will probably be more adversely affected because they are, in general , more intolerant of human presence and activity than are cottontails. The return of rabbits to rehabilitated areas will depend on the degree of survival of populations in the surrounding areas and on revegetation by shrubs such as big sagebrush which can provide adequate cover and protection. All resident bird populations will probably be affected by the planned activities at the Keenesburg mine site. The destruction of habitat, food supply and nesting areas will cause a decrease in resident populations. Most will find other neighboring habitat, causing a secondary impact as food supplies decrease. Predator population may decrease as reptiles and smaller mammals relocate or are killed by the mining activity. The predator population could be increased when recla- mation begins by providing simple perching areas around the mine site. This would: 1 ) increase the predator populations which were driven out during mining 2) decrease rabbit infestation which can destroy young sprouting grasses vital to the reclamation project. There are no deer populations which could be affected by mining activity. The antelope population is minor, but mining activities and the fencing of mining operations will affect their population. Most large game mammals inhabit the major tributaries of the South Platte Valley, such as Kiowa Creek and Crow Creek, and the more irrigated areas of the Platte itself. After reviewing the preliminary Keenesburg coal mining proposal , the Colorado Division of Wildlife stated in a letter that mirgtng opera- tion would have "very little impact on the area 's wildlife." 48 Colorado Division on Wildlife, Letter of 6 October 1978. Refer to Appendix B for complete text of letter. -125- G. Noise Impacts The tranquility of the mining area will be disturbed by all mining operations. Noise impacts will be created by blasting operations, dragline operations, mobile equipment, and coal processing operations. But these sounds will be absorbed within a relative short distance. Animals become readily adapted to noise and are less distrubed because of familiarity with these sounds. The closest inhabitants, 1 .9 miles away, will not be disturbed by the noise. -126- H. Visual Impacts The visual impact caused by the mining operation should not be severe due to its rather remote location. Items of operating equipment visible for some distance will be the coal stockpile facility with its conveyor, lowering tube, and covered stockpile. The dragline boom will also be visible. During the hours of darkness the lights on the dragline boom will be visible but only when pointed in the direction of the viewer. The mast of the overburden dirll may also be visible from a distance. All structures will be painted to blend well with the surrounding area. The area around the shop-office complex will be landscaped to give a pleasant appearance. Debris will not be allowed to accumulate so as to create a cluttered look. The spoil piles will be leveled and seeded as soon as practical preventing a large area from remaining in a disrupted condition. Dust will be generated during blasting but will dissipate rapidly and should create a visual impact of short duration. Other mobile equipment will be visible from time to time but is not expected to create any severe visual impacts. -127- I . Water Use Impacts The major water use during the mining operation will be for dust suppression and irrigation. These needs will be supplied from the water which is pumped out of the pit into settling ponds. The potable water needs which include shop, bathhouse, office, fire protection and sanitary will be supplied from wells to be drilled on the property. Excess potable water will supplement the pit water where needed. Water seeding into the pit as well as the water obtained from wells drilled on the property will come from the Laramie - Fox Hills aquifer. Water from this aquifer would normally flow toward the Box Elder - South Platte drainage system. Water taken from this aquifer which is not consumed during the mining operation will be returned to the drainage system from which it was taken . Irrigation water needed for reclamation is expected to total about 30 acre-feet/year. Some water (pit water if available) will be consumed as it is used for dust suppression on the haul roads. Most of this loss will be due to evaporation other water uses may not consume the water but merely delay its transit into the drainage basin. Water is not expected to be lost to runoff due to the sandy soil which allows water to soak in rapidly. The potable water needed to supply showers and sanitary facilities will normally amount to about 67 gallons per employee per day (2 acre feet per year). Much of this water will return to the drainage system through the leach field. Haul road dust suppression water use will be approximately 6 acre feet per year. Other water uses are expected to be minimal so the total water use will be about 39 acre feet/year much of which will find its way back into the drainage system after a short delay in transit. -12E- I1 1 '-� V. BIBLIOGRAPH\` V. BIBLIOGRAPHY 1 . Abt Associated, Inc. , Draft Social Assessment of the Proposed Narrows Unit and Alternatives Thereto (Cambridge 1974) . 2. Air Conservation, AAAS Publication No. 80, Air Conservation Commission (Washington 1965) . 3. Berg, W.A. , Disturbed Lands Research (Colorado State University, 1978). 4. Berg, W.A. , Soil and Vegetation Inventory Revegetation Research Keenesburg Area (Colorado State University, 1978). 5. Census of Housing, 1970, U.S. Bureau of the Census, Table 3. 6. Chambers, L.A. , "Classifications and Extent of Air Pollution Problems," Air Pollution (New York 1968) , I, 21 . 7. Climate and Man-Yearbook of Agriculture, U.S. Department of Agriculture (Washington 1941 ) . 8. Climate of the States, Vol . 2, U.S. Department of Commerce (Port Washington 1974). 9. Colorado Archaeologist's Office. 10. Colorado Division of Wildlife Letter of 25 June 1974. 11 . Colorado Division of Wildlife Letter of 6 October 1978. 12. Colorado Marketing Manual , 1972, Colorado Interstate Gas Company. 13. Consolidated Report on Elementary and Secondary Education in Colorado, 1973, Colorado Department of Education (Denver 1973). 14. Cultural Resource Consultants, Inc. , Letter of 10 November 1978. 15. Final Environmental Statement, Narrows Unit, South Platte Division, Colorado (Bureau of Reclamation, U.S. Department of the Interior, 1-9767- 16. Federal Bald Eagle Act, 16 U.S.C. 668-668d. 17. Federal Register, Endangered Species Act of 1973, Public Law 93-205; 87 Statute 884. 18. Greeley Area Chamber of Commerce Survey (May 1978). 19. Greeley Human Resources Report (Greeley Human Resources Commission, undated). -131- 20. Greeley Manpower Summary, Colorado Division of Employment Research and Analysis Section . 21 . Hopper, Richard M. , Evaluation of the Impact of the Narrows Unit Project on Migratory Birds and Hunting Opportunities in the South Platte Valley (Denver 1965). 22. Housing Authorized by Building Permits, U.S. Department of Commerce, C40 Series, selected issues. 23. Interim Colorado Comprehensive Outdoor Recreation Plan, Colorado Division of Parks and Outdoor Recreation. 24. Land Use Program for Colorado, Report by the Colorado Land Use Commission (Denver, undated) . 25. McKee, J .E. , and T.R. Rice, "Clouds in the Crystal Ball ," Journal of American Water Works Association, May 1964. 26. McWhorter, D.B. , Water Resources and Impact Evaluation for Proposed Mine Site (Colorado State University, 1978). 27. The Metropolitan Denver Home Builder, Home Builders Association of Metropolitan Denver. 28. Morgan County Wildlife Conservation Officer. 29. Narrows Unit. See Final Environmental Statement, Narrows Unit, South Platte Division, Colorado. 30. Nyberg, Bartell , "Yes, Pelicans in Colorado", Empire Magazine (Denver Post supplement) 16 March 1975, 28-32. 31 . Oblinger-Smith Corporation, Consultants in Planning , Design and Development (1972). 32. Oosting, H.J. , The Study of Plant Communities (San Francisco and London 1956) . 33. Pupil Membership and Related Information, 1970, Colorado Department of Education, Statistical Division . 34. Regional and Community Population Projections, Larimer-Weld Regional Council of Governments (1977) . 35. Rivkin/Carson, Economic Development and Water Resource Investments, Report to the Bureau of Reclamation (Washington 1973 ). 36. Smith, Robert L. , The Ecology of Man: An Ecosystem Approach (New York 1972). 37. Traffic Volume Map, 1970, Colorado State Department of Highways. -132- V . BIBLIOGRAPHY 1 . Abt Associated, Inc. , Draft Social Assessment of the Proposed Narrows Unit and Alternatives Thereto (Cambridge 1974) . 2. Air Conservation, AAAS Publication No. 80, Air Conservation Commission (Washington 1965) . 3. Berg, W.A. , Disturbed Lands Research (Colorado State University, 1978). 4. Berg, W.A. , Soil and Vegetation Inventory Reveqetation Research Keenesburq Area (Colorado State University, 1978). 5. Census of Housing, 1970, U.S. Bureau of the Census, Table 3. 6. Chambers, L.A. , "Classifications and Extent of Air Pollution Problems," Air Pollution (New York 1968) , I, 21 . 7. Climate and Man-Yearbook of Agriculture, U.S. Department of Agriculture (Washington 1941 ) . 8. Climate of the States, Vol . 2, U.S. Department of Commerce (Port Washington 1974). 9. Colorado Archaeologist's Office. 10. Colorado Division of Wildlife Letter of 25 June 1974. 11 . Colorado Division of Wildlife Letter of 6 October 1978. 12. Colorado Marketing Manual , 1972, Colorado Interstate Gas Company. 13. Consolidated Report on Elementary and Secondary Education in Colorado, 1973, Colorado Department of Education (Denver 1973). 14. Cultural Resource Consultants, Inc. , Letter of 10 November 1978. 15. Final Environmental Statement, Narrows Unit, South Platte Division, Colorado (Bureau of Reclamation, U.S. Department of the Interior, 1976). 16. Federal Bald Eagle Act, 16 U.S. C. 668-668d. 17. Federal Register, Endangered Species Act of 1973, Public Law 93-205; 87 Statute 884. 18. Greeley Area Chamber of Canmerce Survey (May 1978). 19. Greeley Human Resources Report (Greeley Human Resources Commission, undated). -131- 38. United States Census of Population, 1970, "General Social and Economic Characteristics, Colorado," U.S. Bureau of the Census (Washington 1972). 39. United States Census of Population, 1970, "Number of Inhabitants, Colorado," U.S. Bureau of the Census (Washington 1971 ). 40. United States List of Endangered Fauna, Fish and Wildlife Service (Washington 1974) . 41 . "The Use of Water Supply to Restrict Regional Population Growth," Water Newsletter, 13 June 1974. 42. Water and Sewer Facility Plan for Weld County, Colorado, Report by the Colorado Division of Planning (Denver 1972). 43. Weber, Don T. , Narrows Pre-Impoundment Investigation, Colorado Department of Game, Fish and Parks (Denver 1975 and 1976) . 44. Weld County Facts, Greeley Chamber of Commerce (Greeley 1978) . 45. Wilson, Woodrow W. , "Pumping Tests in Colorado," Colorado Ground Water Circular, No. 11 , (Denver 1965) . -133- Q n z w a a Q APPENDIX A - a k RESEARCH STUDIES FOR THE PROPOSED SITE 1. • Soil and Vegetation Inventory • Revegetation Research • Keenesburg Area 2.Water Resources and Impact Evaluation For: • A Proposed Mining Site - Weld County, Colorado ADOLPH COORS COMPANY GOLDEN, COLORADO • SOIL AND VEGETATION INVENTORY • REVEGETATION RESEARCH • KEENESBURG AREA November 1978 SOIL AND VEGETATION INVENTORY REVEGETATION RESEARCH KEENESBURG AREA VEGETATION D.N. Hyder SOILS COORDINATOR Dale Romine REVEGETATION W.A. Berg R.D. Heil D.N. Ryder W.A. Berg Department of Agronomy Colorado State University Fort Collins, Colorado 80523 This study is being conducted for the Adolph Coors Company. Appreciation is expressed to the Soil Conservation Service - USDA for supplying some of the soils information and seeds of some native species. SOIL AND VEGETATION INVENTORY AND REVEGETATION RESEARCH ON THE PROPOSED KEENESBURG SURFACE COAL MINE ABSTRACT The feasibility of surface mining coal from the Laramie Formation north of Keenesburg, Colorado is under investigation by Adolph Coors Company. As a part of the study the Department of Agronomy, Colorado State University contracted to inventory soils and vegetation on the six square mile site and to carry out revegetation research. Wind-deposited sand averaging about 20 feet deep lies above the bedded clay shales of the Laramie Formation. Two soil series in 4 soil mapping units cover most of the area that may be disturbed west of the Ennis Draw. The soils are very sandy and thus are very sus- ceptible to wind erosion when disturbed. The Osgood soil series which covers about one-third of the area west of Ennis Draw is the most suitable soil for use as topsoil; approximately 30 inches of the sand Al horizon and the loamy sand B2 could be used. The Valent soil series which covers most of the remainder of the area has a surface layer 4 to 6 inches thick which could be used as topsoil. Tests on the soils show no adverse chemical or fertility char- acteristics other than that the subsurface horizons are deficient in plant-available phosphorus. The clayey overburden is moderately salty and sodic. Thus a minimum of 3 feet of sand over the clayey spoil is recommended for reclamation. Almost all of the proposed mine area west of Ennis Draw is in the deep sand range site which is dominated by sandsage and prairie sandreed. No rare or endangered plant species were found on the deep sand range site. In Ennis Draw the range site is a sandy meadow. Here one species, tulip gentian (Eustoma gradiflorum) , was found that is listed as rare in the computerized Plant Information Network of Colorado State University. However, this species is not on the Colorado or national lists of rare or endangered species. The revegetation studies showed that intensive management was required to establish ground cover adequate to stabilize drastically disturbed topsoil. The vegetation was established by seeding a mix of native grass species, applying manure to stabilize the sand, and then applying 9 inches of irrigation water over a 3-month period. Applying 9 inches of water to the soil surface requires about a total of 13 inches as about 30% is lost to evaporation when sprink- ling. The present concept is to irrigate for establishment only during the first growing season. With proper long-term grazing management most of the seeded vegetation should persist. ii TABLE OF CONTENTS ASBTRACT ii LIST OF TABLES V REVEGETATION RECOMMENDATIONS 1 SOILS 4 Soil Mappij Units 4 SOIL MAPPING UNIT NO. 1 . Osgood sand, 0-3% . . . 5 SOIL MAPPING UNIT NO. 2 . Vona-like, 0-3% . . . 5 SOIL MAPPING UNIT NO. 3 . Valent sand, 0-3% . . 6 SOIL MAPPING UNIT NO. 4 . Valent sand, 3-9% . . 6 SOIL MAPPING UNIT NO. 5 . Valent-sand, 1-15% . . 7 SOIL MAPPING UNIT NO. 6 . Valent-Loup-Boel, 0-2%. 7 SOIL MAPPING UNIT NO. 7 . Loup-Boel, 0-3% . . . . 8 Evaluation of Field and Laboratory Soil Data . . . 8 Soil Mapping Unit Interpretations for Sources for Topsoil 10 SOIL MAPPING UNIT NO. 1 10 SOIL MAPPING UNIT NO. 2 11 SOIL MAPPING UNIT NO. 3 & 4 11 SOIL MAPPING UNIT NO. 5 11 SOIL MAPPING UNIT NO. 6 12 SOIL MAPPING UNIT NO. 7 12 Important Farmlands 12 13 Overburden iii VEGETATION 15 Sandsage-Prairie Sandreed Association 15 Sandsage-Prairie Sandreed Association Reference Area 20 Saltgrass-Alkali Sacaton Meadow Association • 22 Saltgrass-Alkali Sacaton Meadow Association Reference Area 23 REVEGETATION 25 Sprinkler Irrigation 25 Species Establishment and Adaptability 26 Species Established From Seed Mixture 28 Sod Transplanting 29 Straw and Manure Mulches and Nitrogen Fertilization 30 Rodent, Broadleaf Weed and Insect Control 31 Depth of Sand over Clay 32 Grazing Management of Rehabilitated Areas 33 APPENDIX A Soil Series Descriptions 36 B Laboratory Data on Soils 41 C Laboratory Data on Overburden 44 D Revegetation Plot Experimental Design 47 E Precipitation and Irrigation 54 F' Soils and Vegetative Map 55 iv LIST OF TABLES TABLE PAGE 1 Plant species found 16 2 Reference Area for the Sandsage-Prairie Sandreed association: Frequencies of occurrence (%) in 200 placements of a 12 by 12-inch quadrat, June 22, 1978 21. 3 Reference Area for the Saltgrass-Alkali Sacaton meadow Association: Frequencies of occurrence (%) in 200 placements of a 12 by 12-inch quadrat, July 11, 1978 . . 24 4 Vegetation cover on 6 September 1978 as influenced by sprinkler irrigation on plots seeded 24 May 1978 26 5 Stand density and herbaceous ground cover produced on individual species plots seeded at the rate of 20 pure live seeds per square foot on 24 May 1978 27 6 Density by species measured on 10 August on plots seeded to species mix on 24 May 1978 29 7 Plant density and cover as influenced by mulch and nitrogen treatments on plots seeded on 24 May 1978 31 v REVEGETATION RECOMMENDATIONS The following recommendations are based on the revege- tation plot studies, field observations and general experi- ence. Depth of Sand over Clay Shale We recommend a minimum of three feet of sand over the clayey spoil. The top foot should consist of existing top soil. This recommendation is largely subjective, because the depth-of-sand plots can not reveal ecological conse- quences for several years. Shallow sand depths, as found in the northeast corner of section 30, tend to exclude sand- sage and the important tall grasses prairie sandreed and sand bluestem. We also recommend pitting or furrowing of the clay shale spoil on the contour, if there is appreciable slope, before covering with sand to hold sub-surface water and prevent downslope seeps. Seed Mixture We recommend the following seed mixture : Prairie sandreed at 10 pls (pure live seed) /sq. ft. Sand bluestem at 4 pls, Blue grama at 4 pls, Western wheatgrass at 4 pls, Sand dropseed at 1 pls, Indian ricegrass at 1 pls, Sideoats grama at 1 pls, Little bluestem at 1 pls. Compared to the seed mixture used. on the plot trials , the recommended mixture includes more sand bluestem, which is more common in the natural plant community than was known when the plots were prepared. 2 The seed mixture should not include sandsage. How- ever, we recommend that sandsage inflorescences be har- vested at seed-ripe time and broadcast along lines ori- ented from southwest to northeast and spaced about 50 feet apart. However, since it is apparent that herbi- cides will have to be used for control of broadleaf annuals during grass seedling establishment, seeding of the sandsage should be in late fall after grass establish- ment. Seeding and Mulching We recommend seeding in mid-May and then mulching with manure at about 30 tons per acre dry weight. How- ever, it is recognized that the sand topsoil placed at times other than this optimum seeding time will have to be stabilized. An approach is to spread the manure immediately after topsoil placement, then to drill seed into and through the manure mulch in mid-May. This technique will probably result in a less uniform stand than obtained by seeding and then mulching. However, with timely irrigation it should be possible to esta- bligh a satisfactory stand. With the 30 ton/acre rate of manure no commercial fertilizer should be needed. Drilling will require use of a drill adapated to feed light chaffy seed and to control depth of seed place- ment (about z") in the sand. Sewage sludge could be used to supply N and P to the seeding. However, sewage sludge would not be nearly as effective as manure as a surface mulch to control wind erosion. Irrigation Begin sprinkler irrigation immediately after seeding and continue applying about 0 .25 inch daily for two to three weeks for germination and emergence. Then irriga- tion can be suspended for about three weeks, but one must watch the condition of seedlings to detect advancing drought or damage by rabbits and insects. When the seedlings are about three weeks old, one should sprinkle daily for three or four days to promote the growth of adventitious roots . During the next six to eight weeks , water weekly as needed. Then water daily once again for three or four days to promote adventitious roots. Continue watering bi-weekly in late summer. Irrigation would require a total application of about 9 inches of water to the soil surface. Assuming sprinkler irrigation is 70% efficient this would require a total of 13 inches of water or slightly over 1 acre foot per acre to be revegetated. 3 Weed Control Seeds of annual weedy species will be abundant in topsoil and manure . Thus herbicide treatment will be required to establish an adequate stand and ground cover dominated by the warm-season grasses. An application of bromoxynil when grasses are in the seedling stage and a later season application of 2, 4-D should control the broadleaf annuals. Grazing Management Good management will be required to keep revegetated areas from being overgrazed. A grazing management plan and grazing agreements with landowners and lessees should have a priority equal to topsoiling, seeding, mulching, or irrigation. SOILS This study included field investigations to verify the kind, extent, and distribution of soils as shown by the existing Soil Conservation Service, USDA, Standard Soil Survey of South Weld County, Colorado, which was completed in 1975. In addition, soils were sampled for laboratory characterization of properties important for assessing reclamation alternatives. Laboratory analyses were not made for soils of the meadow area since it is not proposed as part of the actual mining site. The diversity of soils found on the study area is not great. This reflects the nature of the parent material which is wind-deposited sand comprised mainly of quartz . Due to the nature of the parent material, the range in chemical and physical properties is narrow. Rationale for determining the kind and amount of soil laboratory characterization data needed to adequately describe the soil resources was based on the nature of the parent material. The likelihood of toxic elements and/or other chemical constituents detrimental to either plant growth and/or environmental quality is highly remote considering the sandy wind-blown parent material . Thus, the soil properties selected for study were those of primary importance in establishing the basic soil-plant nutrient-plant moisture relationship that exist within the study area. Soil Mapping Units Two soil series, the Valent and the Osgood, make up most of the area on the proposed mine site west of Ennis Draw. Both soils are extremely sandy. The Osgood is a deeply developed soil with a slight increase in clay in the subsoil, whereas the Valent has shallower soil develop- ment as shown by lighter colors in the subsoil and with no increase in clay with depth. Detailed soil series descrip- tions are in Appendix A. The following soil mapping des- criptions are keyed into the soil map accompanying this report. 5 SOIL MAPPING UNIT NO. 1 : Osgood Sand (variant) - 0-3% slopes. These are deep, level to gently sloping, well-drained sandy soils that formed in wind-lain sands. Typically the surface layer is grayish brown sand and ranges from 14 to 18 inches thick. It overlies a transition layer 10 to 14 inches thick which normally has characteristics similar to the surface layer. This layer overlies a subsoil layer ranging from 16 to 20 inches thick. Weak lamellae with loamy sand and sandy loam textures occur in the subsoil. The subsoil is underlain to a depth of 60 inches with loamy sand and sand. Permeability is rapid to moderately rapid. Available water holding capacity is moderate. Effective rooting depth is 60 inches or more. Surface runoff is very slow and water erosion hazard is low. Wind erosion hazard is high on disturbed areas. Small areas of soils with sandy loam and sandy clay loam sub- soils occur within this mapping unit. In these areas the subsoil generally occurs at a shallower depth. Included in this mapping unit can be small areas of Valent soils which can comprise 0-5% of the unit. Range Site Name : Deep Sand Range Site Land Capability Classification: Irrigated: lye Non-irrigated: VIe SOIL MAPPING UNIT NO. 2 : Vona-like loamy sand - 0-3% slopes. The mapping unit, which is very limited in extent, consists of moderately deep, well-drained soils that formed in wind-laid deposits over residual shale. Slopes range from 0 to 3 percent. Typically the surface layer is grayish brown loamy sand about 6 inches thick. This surface layer is underlain by a transition layer about 6 inches thick of grayish brown fine sandy loam. This layer is underlain to a depth of about 32 inches by yellowish brown sandy clay loam. Underlying this layer is residual shale material of the Laramie formation. Permeability is moderate. Available water holding capacity is moderate to high. Surface runoff is low and water erosion hazard is low. Wind erosion potential is high on disturbed areas. Range Site Name : Sandy Plains Land Capability Classification : Irrigated: lye Non--irrigated: VIe 6 SOIL MAPPING UNIT NO. 3 : Valent Sand - 0-3% slopes. These are deep, level to gently sloping, excessively-drained sandy soils that formed in wind deposited sands. Typically the surface layer is brown sand approximately 8 inches thick. A transitional layer 10 to 12 inches thick occurs between the surface soil and substratum. The underlying material to a depth of 60 inches is brown sand. Permeability is rapid. Available water capacity is low to moderate. Effective rooting depth is 60 inches or more. Surface runoff is very slow and the water erosion hazard is low. Wind erosion potential is high. Included in this unit are small areas of Osgood soils which comprises 10 to 15 percent of the unit. Range Site Name: Deep Sand Land Capability Classification: Irrigated: IVe Non-irrigated: VIe SOIL MAPPING UNIT NO. 4 : Valent Sand - 3-9% slopes. This is a deep, excessively-drained soil formed in wind-laid deposits on gently sloping uplands. Slopes range from 3 to 9 percent . Typically the surface layer is brown sand approximately 6 inches thick. A transition layer (AC horizon) of brown sand approxi- mately 8 to 10 inches thick occurs between the surface soil and the substratum. The underlying material, to a depth of 60 inches is brown sand. Permeability is rapid. Available water capacity is low to moderate. Effective rooting depth is 60 inches or more. Surface runoff is low and water erosion hazard is low. Wind erosion potential is very high. Included in this unit are small areas of Osgood soils which make up less than 10 percent of the unit. Range Site Name : Deep Sand Range Site Land Capability Classification: Irrigated: lye Non-irrigated: VIe 7 SOIL MAPPING UNIT NO. 5 : Valent Sand - 1-15% slopes. This is a deep, excessively-drained soil formed in wind-laid deposits on nearly level to sloping uplands. Typically the surface layer is brown sand about 5 inches thick. The underlying material, to a depth of 60 inches is brown sand. The soil in this unit differs from the other Valent soils found in the study area in that there is evidence of recent wind erosion. Thus the surface layer is somewhat thinner, and in some places is absent. In addition, the Valent soil in this unit lacks a transition layer (AC horizon) that is found in the other Valent soil mapping units. Some blowouts are found within this soil mapping unit. Permeability is rapid. Available water holding capacity is low to moderate. Effective rooting depth is 60 inches or more. This unit is particularly susceptible to wind erosion. Surface runoff is low and water erosion hazard is low. These soils are not suited for cropping except under irrigation. This unit is comprised of essentially 100 percent Valent soil as described above. Range Site Name : Deep Sand Range Site Land Capability Classification: Irrigated: lye Non-irrigated: VIe SOIL MAPPING UNIT NO. 6 : Valent-Loup-Boel - 0-2% slopes. This mapping unit consists of a complex of deep excessively- drained, somewhat poorly, and poorly-drained soils. The Valent soils, which make up approximately 75 percent of the area, are similar to those described in the other Valent mapping units except that mottling is common at depths of 50 to 60 inches. This indicates the upper limit of a water table. The Loup soils are deep poorly-drained soils in low lying areas that have formed in sandy alluvium. Boel soils are deep, somewhat poorly-drained soils that formed in stratified sandy alluvium. They occur primarily in low lying areas. Permeability of these soils is rapid. Available water holding capacity is low to moderate. In the Loup soils a water table is present at or near the surface during the spring and at about 36 inches below the surface in the fall. A water table is usually present about 24 to 36 inches below the surface in Boel soils and at 50 to 60 inches in the Valent. Surface runoff is low and water erosion hazard is low. Wind erosion hazard is high on disturbed areas. Range Site Name : A complex of Deep Sand and Sandy Meadow Land Capability Classification : Irrigated: lye Non-irrigated: VIe 8 SOIL MAPPING UNIT NO. 7 : Loup-Boel loamy sands - 0-3% slopes. This mapping unit consists of deep, somewhat poorly and poorly- drained soils that formed in sandy alluvium. It occupies bottoms and drainageways. Slopes range from 0 to 3 percent. Loup soils make up about 55 percent of the unit. The Boel soils occupy the slightly higher elevations and make up about 35 percent of the unit. About 10% of the unit is made up of Osgood and Valent sand. The Loup soil is deep, poorly-drained, formed in sand alluvium. Typically the surface layer is very dark grayish brown, mottled, loamy sand. This is underlain by about 24 inches of light brownish gray, mottled, loamy sand. Underlying this layer to a depth of 60 inches is a light brownish gray, mottled, sandy loam. Permeability is rapid. Available water capacity is moderate. Permeability is rapid. Avail- able water capacity is moderate. Normally a water table is present at or near the surface in the fall. Surface runoff is slow and water erosion hazard is low. Wind erosion is potentially high on disturbed areas. The Boel soil is deep, somewhat poorly-drained formed in stra- tified sandy alluvium. Typically the surface layer is grayish brown, lomay sand about 14 inches thick. Underlying this surface layer to a depth of 60 inches is pale brown, stratified, mottled, loamy sand. Range Site Name: Sandy Meadow Range Site Land Capability Classification: Irrigated: lye Non--irrigated: VIe Evaluation of Field and Laboratory Soil Data 1. All soil materials are highly susceptible to wind erosion. Both the surface soils, which are higher in organic matter and the subsoils of the Osgood series which are slightly finer-textured offer the greatest potential for minimizing wind erosion in a reclamation effort. 2 . Particle size analyses and soil moisture determina- tions show that the materials with the highest avail- able water holding capacity occur within the B horizons of the Osgood soils . Sand sieve analyses show that the very fine sand content is somewhat higher in the surface soil of the Osgood series than in the Valent. 9 This, combined with the slightly higher silt and clay content of the Osgood soils suggest that they would be slightly more resistant to wind erosion, have a slightly higher water holding capacity and thus should provide a better medium for plant growth and be more stable. An inch of water would pene- trate about 18 inches into the sand surface soils when initially dry (calculations made from soils laboratory data, appendix B) . This calculated depth of water penetration is in agreement with a field observation made on 24 October when it was found that water had penetrated the sand to 28 inches after 1. 9 inches of precipitation on 21-23 October. 3. Plant available P levels are sufficient in the surface horizons but decline rapidly with depth. Alteration of the surface soil during the typical redistribution process may result in mixing of existing topsoil and subsoil materials and could result in lower available P levels. Thus, compos- ite surface soil samples should be obtained follow- ing topsoil redistribution to determine the P status of the soil at that time. 4 . Organic matter levels are highest in the surface layers and decrease rapidly with depth. 5 . Available K levels appear to be adequate in all horizons of all soils except for the C horizon of one of the Valent soil profiles and the Cca horizon of one of the Osgood soil samples. 6 . Critical levels for zinc, iron, copper, and mangan- ese relative to deficiencies of these elements on native range are not well known. In general, the available levels of these elements in the surface soils are adequate for most agronomic crops, thus it is assumed that they are adequate for most species that would be grown in the area. Avail- able iron is considered adequate throughout the entire profile in all soils investigated. In general, the same is true for copper and manganese. Available zinc, on the other hand, is low except for the surface layers . However, it must be remembered that the low rating is based on the zinc status for agronomic crops . Perhaps zinc should be considered suspect but not limiting in all materials with zinc levels below 0.5 ppm. 10 Soil Mapping Unit Interpretations for Sources of Topsoil These interpretations were developed to show the extent and distribution of soils in terms of characteristics important for planning a reclamation program. Soil mapping units 1 through 5 are arranged from first to last in terms of best to poorest source and suitability of topsoil. SOIL MAPPING UNIT NO. 1 This unit reflects the extent and location of soils which offer the greatest potential for developing alterna- tive reclamation procedures. Although the surface soils are sandy and have a high susceptibility to wind erosion, they comprise the most stable materials in terms of erosion from the standpoint of organic matter content. The surface layer and the layers immediately below the surface to a combined depth of approximately 30 inches would be consi- dered as the best source of topsoil within the study area. The subsoil (B horizon) materials also have favorable topsoil material characteristics. From the standpoint of texture, the subsoil materials would be less susceptible to wind erosion than the surface materials of this unit. However, because of the lower organic matter content in the B horizon materials the wind erodibility potential can be considered as being essentially the same as the A hori- zon materials . The surface soils have a more favorable soil fertility status. The use of these materials in the development of a reclamation plan can be considered in several ways : 1 . The horizons salvaged separately and replaced in order. 2 . The A and B horizon salvaged and mixed together. 3 . Use the above mixture for redistribution to other areas where topsoil materials are inadequate. This alternative would reduce the thickness of more favorable soil conditions in the areas where these soils presently occur, but would enhance the soil. conditions in other areas. 4 . Salvage "A" horizon materials separately from the "B" horizon and use the "B" horizon materials to underlie topsoil materials in areas where topsoil. materials are inadequate. Because of the distributional pattern of this unit with respect to areas of other soils , there exists a good poten- tial for maximizing the utilization of these materials in the development of an overall reclamation plan. 11 SOIL MAPPING UNIT NO. 2 This unit is very limited in extent, it shows the loca- tion of soils where shale was encountered within a 60-inch depth. Both the subsoil and underlying shale material could be utilized for stabilizing roads. From a revegetation and stabilization point of view, the top 12 inches from this unit would be suitable topsoil material. SOIL MAPPING UNITS NO. 3 & 4 These units reflects the extent and location of soils which have approximately 4 to 6 inches of surface soil that if salvaged would be more suitable as topsoil material than any of the materials below this depth. The soil layer (AC horizons of the Valent soil as des- cribed in this report) that underlies the surface layer varies in thickness from 8 to 12 inches and is slightly higher in organic matter and in fertility than the materials below. However, this layer is more like the underlying ma- terial than the surface layer. The potential benefit of salvaging this material separately to use as subsurface soil is questionable. And since it is more like the underlying materials (C horizons) it is not recommended that it be mixed with the A horizon materials. SOIL MAPPING UNIT NO. 5 This unit reflects the extent and location of soils which have the thinnest and least uniform occurrence of topsoil material. These areas reflect recent wind erosion activities . The topography is described as being "choppy" and a number of "blow-out" areas occur. These areas will. become very susceptible to wind erosion if and when they are disturbed. In some areas the surface layer is very similar in physical and chemical characteristics to the substratum (C horizon) materials of the Valent soils . If volume of available topsoil calculations are made for this unit, it is recommended that the volume be reduced by 50 percent, if the calculations are based on the thickness of the surface horizon of the typical Valent soil as des- cribed in this report. 12 SOIL MAPPING UNIT NO. 6 This unit reflects the extent and location of soils which are dominantly like the soils delineated in soil mapping unit no. 3 except for the following: these areas lie adjacent to the meadow area and include small areas of the poorly drained Loup and Boel soils. Mottling occurs at a depth of about 50 inches in the Valent soils which suggests the presence of either a past or present seasonal water table. In addition, these areas may be part of the alluvial valley and may need to be considered differently from the upland areas in the development of a reclamation plan. In terms of availability and nature of topsoil materials, these poorly drained areas are very similar to soil mapping unit no. 3 . SOIL MAPPING UNIT NO. 7 This unit identifies the extent and location of the meadow lands found in the study area. They are identified but not discussed because they are not part of the pro- posed mining area. Important Farmlands On January 31, 1978 the Federal Register reported the final rules for the implementation and conducting of a national program for inventorying prime and unique farm- land. Prime farmland is defined as land that has the best combinations of physical and chemical characteristics for producing food, feed, forage , fiber, and oilseed crops and is also available for these uses . In general , prime farm- lands have an adequate and dependable water supply from precipitation or irrigation, a favorable temperature and growing season and acceptable chemical qualities. According to the above definitions no important farm- lans occur within the study area. It is evident from old field boundaries and vegetation that a portion of Section 26 was once farmed and then left to revert to range. Dry- land farming on sand has not proven feasible in this area. 13 Overburden Forty-one samples of individual overburden strata and 3 composite samples from 3 core holes were analyzed for physical and chemical properties important to reclamation (appendix C) . The typical Laramie formation overburden on the proposed mine site is described as follows : pH, 7 . 8 Within the pH range expected for calcareous material - this pH should not pose a problem for native species to be used in revegetation. Soluble salts Somewhat salty - unsuitable for 4-6 mmhos/cm surface soil but should be okay as a soil material acting as a deep reservoir to hold plant- available water. Sodium Adsorption Ratio This much sodium will limit the 10-16 rate of water movement into and through this clayey material if soluble salts are leached out. Plant Available Nutrients N and P very deficient - others adequate . Texture, clay Unsuitable as surface soil material, if placed beneath sand should be acceptable because of its large water holding capacity. Possible Toxic Ions Analysis for plant-available selenium show low or moderate concentrations by the 4-hour hot-water extraction method. Plant-available molybdenum is low to moderate in most of the samples. Two of the samples tested high in Mo in relation to the other samples by the (NH4) ,CO3 test for plant-avail- able Mo, both of these samples were dark gray carbonaceous shales. One sample tested very high in B (>4 ppm B, 5-minute 14 hot water extractable) and 5 samples tested in the marginal range (2-4 ppm B) . With three feet of sand placed over the mixed spoil these trace elements should not pose plant uptake problems. It is suggested that Mo and B be determined on plants grown on the depth of sand-over- clay study in 1979 to check out this interpretation. Because of the clayey, moderately saline and moderately sodic nature of the overburden we recommend that a minimum of 3 feet of sandy material be placed over spoils originating from the Laramie formation. This recommendation should be reviewed when longer term information is available from the depths of sand-over-clay study (mentioned in the next chapter) is available. Soil test analyses were made of two-foot increments of the sand (0 to 14 ' ) overlying the Laramie formation on one core hole . The sand is calcareous at a dpeth of 6 to 8 feet, poses no salinity hazard, and at depths below 4 feet is low in organic matter and extremely low in plant-available phos- phorus (Appendix C) . These and other soil (Appendix B) and overburden analyses (Appendix C) indicate that the sand at depths of 4 to 10 feet which is above the zone of maximum lime accumulation (obvious as white splotches and streaks) and the more soluble salt accumulations (visible below or within the maximum lime accumulation zone as crystals) is suitable as subsurface plant growth material . 4 VEGETATION A sandsage-prairie sandreed plant association was the only vegetation type mapped on the upland which is classi- fied as a Deep Sand Range Site in the Soil Conservation Service system and includes all of soil mapping units 1, 3, 4 , and 5 . A saltgrass-alkali sacaton meadow association meanders through sections 30 and 31, this is classified as a Sandy Meadow Range Site in the Soil Conservation Service system and includes all of soil mapping unit 7. A complex of Sandy Meadow and Deep Sand Range Sites is found in soil mapping unit 6 . One hundred and five plant species (Table 1) were found in the six sections surveyed (sections 30 and 31 of T. 3N, R. 63W. and sections 25 , 26 , 35, and 36 of T. 3N. , R. 64W) . Specimens of most of the species were collected and mounted. Identification of the mounted plants were verified by per- sonnel of the Colorado State University herbarium. One of the species found in the meadow was tulip gentian (Eustorr2 gradiflorum) (found about 200 feet south of the windmill in section 31) , it is listed as rare in the computerized Plant Information Network of Colorado State University. However, this species is not listed as rare on the Colorado or national lists of rare or endangered species. Sandsage-Prairie Sandreed Association The sandsage-prairie sandreed association, which is classified as a Deep Sand Range Site in the Soil Conserva- tion Service system, occurs on Valent Sand and Osgood Sand soil series. Sub-site differences and variations in range condition create much heterogeneity in the association. The aspect is predominantly sandsage, which provides a crown cover varying from near zero to about 20% , and a density up to about 3, 000 plants per acre . Sandsage is absent to rare on some of the low-lying Valent Sand bor- dering the meadow, and attains greatest cover and density on well-stabilized deep sands. The areas lacking sandsage constitute a small but distinctive sub-site, because the shrub generally is most abundant on Valent Sand. Shrub stands generally are more consistent but less dense on Osgood Sand than on Valent Sand. 16 Table 1 . Plant species found on Keenesburg site . Abfr Abronia fragrans Nutt. ex Hook. Snowball Agda Agropyron dasystachyum (Hook.) Scribn. Thickspike wheatgrass Agsm Agropyron smithii Rydb. Western wheatgrass Alte Allium textile Nels. & Macbr. Textile onion Amco Ambrosia coronopilfolia T. & G. Western ragweed Anha Andropogon hallii Hack. Sand bluestem Arfi Artemisia filifolia Torr. Sandsage Arin Argemone intermedia Sweet Prickly poppy Arlo Aristida Zongiseta Steud. Redstem threeawn Asce Astragalus ceramicus Sheld. Ceramicpod milkvetch Aser Aster ericoides L. Heath aster Asgr AstragaZus gracilis Nutt. Milkvetch Asle Aster Zeucanthemifolius Greene Blue aster Asla AscZepias Zatifolia (Torr.) Raf. Milkweed Bogr Bouteloua gracilis (H.B.K.) Lag. Blue grama Bohi Bouteloua hirsuta Lag. Hairy grama Brte* Bromus tectorum L. Cheatgrass Buda Buchloe dactyloids (Nutt.) Engelm. Buffalograss Calo Calamovilfa longifolia (Hook.) Scribn. in Hack. Prairie sandreed Oahe Carex heliophila Mack. Sun sedge Chle* Chenopodium leptophyllum Nutt. Slimleaf goosefoot Chna Chrysothanmus nausesus graveolens (Nutt.) H. & C. Rabbitbrush Chvi Chrysopsis viZlosa (Pursh) Nutt. ex DC. Hairy golden aster Ciun* Cirsium undulatum (Nutt.) Spreng. Wavyleaf thistle Clse Cleome serrulata Pursh Beeplant Crte* Croton texensis (Klotsch) Muell-Arg. Texas croton Crfe* Cryptantha fendleri (Gray) Greene Fendler hiddenflower Crja Cryptantha jamesii (Torr. ) Payson James hiddenflower Crmi* Cryptantha minima Rydb. Smallflower cryptantha Cysc Cyperus schweinitzii Torr. Schweinitz flatsedge Cuum* Cuscuta umbellata H.B.K. Dodder Devi Delphinium virescens Nutt. Plains larkspur Dist Distichlis stricta (Torr.) Rydb. Saltgrass Elca Elymus canadensis L. Canada wildrye Eqva Equisetum variegatum Schleich. Variegated horsetail Eran* Eriogonum annuum Nutt. Annual buckwheat Eref Eriogonum effusum Nutt. Woody buckwheat Erfl Eriogonum fZavum Nutt. Yellow eriogonun Erbe* Erigeron bellidiastrum Nutt. Annual fleabane Erpu Erigeron pumilus Nutt. Low fleabane Eugl* Euphorbia gZyptosperma Engelm. in Emory Ridgeseed euphorbia Eugr Eustoma grandifZorum (Raf.) Shinners Tulip gentian Evnu Evolvulus nuttallianus R. &. S. Nuttall evolvulus Feoc* Festuca (Vulpia) octoflora Walt. Sixweeks fescue Frac* Franseria acanthicarpa (Hook.) Coville Bursage 17 Table 1 . continued. Glle GZycyrrhiza Zepidota Pursh Licorice Hasp HapZopappus spinulosus (Pursh) DC. Goldenweed Hepe* Helianthus petiolaris Nutt. Prairie sunflower Hoju Hordeum jubatum L. Foxtail barley Ivxa* Iva xanthifolia Nutt. Rag sumpweed Juba Juneus baZticus Willd. Baltic rush Kosc* Kochia scoparia (L.) Schrad. Summercypress Lapo Lathyrus poZymorphus Nutt. Showy peavine Lare* Lappula redowskii (Hornem.) Greene Stickseed ylettuce Lactuca scariola L. r P Pricklly lettuce Lede* Lepidium densiflorwn Schrad. weed Lelu Lesquerella Zudoviciana (Nutt. ) S. Wats Prairie laddpepperpod Lepu Le todact ZonSilver b blhloxrpod P y pungens (Torn ) Rydb. Shrubby phlox Liin Lithospermum inciswn Lehm. Cromwell Lupu* Lupinus pusillus Pursh Rusty lupine Lyju Lygodesmia juncea (Pursh) D. Don. Rush skeletonplant Mavi Mamillaria vivipara (Nutt.) Haw. Melal* Whit cactus Me Zi Zo tus alba Desr. in Lam. White sweetclover Meal* Mentzelia aZbicauZis Dougl. ex Hook. Menu Whitestem mentzelia Mentzelia nuda (Pursh) T. & G. Bractless stickleaf Migl Mirabilis glabra (Wats.) Stand. Four o'clock Mupu Muhlenbergia pungens Thurber Sandhill muhly Oela Oenothera Zatifolia (Rydb.) Munz Oenu Evening primrose Oenothera nuttaZlii Sweet Evening primrose Opfr Opuntia fragilis (Nutt.) Haw. Brittle pricklypear Ophu Opuntia humifusa Raf. Common pricklypear Orhy Oryzopsis hymenoides (R. & S.) Ricker Indian ricegrass Pavi Panicum Virgatum L. Switchgrass Peal Penstemon albidus Nutt. White penstemon Pean Penstemon angustifolius Nutt. ex Pursh Narrowleaf penstemon Peco Petalostemon eompactus (Spreng.) Swezey Compact prairieclover Phho Phlox hoodii Rich. in Frankl. Hoods phlox Phla Physalis Zanceolata Michx. Ground cherry Plpu* Plantago purshii Roem. & Schult. Wooly indianwheat Poar Poa arida Vasey Plains bluegrass Poer* Polygonum ereetum L. Erect knotweed Psdi Psoralea digitata Nutt. Digitate scurfpea Psla Psoralea Zanceolata Pursh Lemon scurfpea Raco Ratibida eolunniJ'era (Nutt.) Woot. & standl. Upright Reflrairieconeflower Redfieldia fZexuona (Thurb. ) Vasey Blowout grass Ruve Rumex venosus Pursh Veiny dock 18 Table 1 . continued. Saka* Salsola kali L. Russian thistle Semu Senecio multicapitatus Greenm. ex Rydb. Groundsel Sial* Sisymbrium altissimum L. Tumblemustard Soca SoZidago canadensis L. Canada goldenrod Spai Sporobolus airoides (Torr.) Torr. Alkali sacaton Sper Sporobolus cryptandrus (Torr.) S. Gray Sand dropseed Spco SphaeraZcea coccinea (Pursh) Rydb. Scarlet globemallow Stco Stipa comata Trin. & Rupr. Needleandthread Taga Tamarix gaZlica L. Salt cedar Taof Taraxacum officinale Wiggars Common dandelion Thme Thelesperma megapotamicum (Spreng.) Kuntze Perennial greenthread Thtr* Thelesperma trifidum (Poir.) Britt. Annual greenthread Trdu Tragopogon dubius Scop. Salsify Trmi* TripterocaZyx micranthus (Torr.) Hook. Wingfruited sandverbena Troc Tradescantia occidentalis (Britton) Smyth Prairie spiderwort Vebr Verbena bracteata Lag. & Rodr. Bigbract verbena Vinu Viola nuttaliii Pursh Nuttall violet Yugl Yucca glacua Nutt. Small soapweed Zygr Zygadenus gramineus Rydb. Grassy deathcamas * Places are annual or biennial. 19 Prairie sandreed is the most typical perennial grass of this association. Western wheatgrass, blue grama, sand dropseed, needle-and-thread, Indian ricegrass, sandhill muhly, and sand bluestem are common associates. With existing range conditions, western wheatgrass, blue grama, sand dropseed, and needle-and-thread are sometimes more dominant than prairie sandreed. Blue grama, in particular, forms localized continuous stands that could be identified as a distinctive sub-site. Needle-and-thread headed out in June and remained evident through most of the summer. In late summer, prairie sandreed and sand bluestem pre- sented a scanty tallgrass aspect where protected from grazing. Perennial forbs were quite abundant and relatively conspicuous when in flower. Residual dead stems of bractless stickleaf attracted attention early in the season when textile onion, silver bladderpod, and ceramicpod milkvetch were in flower. These gave way to prairie spiderwort, showy peavine, snowball , plains larkspur, prickly poppy, evening primroses, bractless stickleaf, and western ragweed, each in their own season. Although the showy flowering plants became highly visible, veiny dock was the only one found in stands thick enough to be considered as dominant or co-dominant among herbaceous plants. This plant association was extremely weedy in 1978. Thick stands of slimleaf goose£oot, whitestem mentzelia, prairie sunflower and annual buckwheat prevailed over most of the area. Cheatgrass was abundant in localized areas of moderate disturbance. By late August, the land- scape was a sea of sunflower. This , prevalence of annual weeds is promoted by favorable weather conditions (that is, favorable to the annuals) and less-than-desirable range condition. Poorest range conditions were found on the abandoned plowed fields in section 26 , and on the steeper edges of old sand dunes, which are oriented along northnorthwest to southsoutheast lines. Extreme local disturbances have created a few blowouts that threaten down-wind areas. Percent vegetation cover was estimated on 100 12" x 12" quadrats near the SE corner of section 31 (ungrazed in 1978) on 13 September 1978. Total cover was 20 . 9% with herbaceous perennials, annuals, and sandsage making up 8 . 4 , 6 .4, and 6 . 1% , respectively. Cover was not determined on the reference area because it was grazed in 1978 . For the Deep Sand Range Site, the Soil Conservation Service lists optimum vegetation ground cover at 40% and median-year herbage production at 1800 pounds air dry per acre. Percentage composition by weight may total as much as 25% prairie sandreed, 15% sand bluestem, 15% needle-and- thread, 10% blue grama, 10% sandsage, 5% other grasses, and 20 3% soapweed. None of the area under consideration attained those levels of composition in 1978 . Cover and production levels were attained only with the inclusion of annual plants, which constituted about 50% of herbaceous cover and biomass. Consequently, there is much room for improvement in range condition and forage production. One the other hand, the area under consideration should not be expected to produce at an optimum for the Deep Sand Range Site, because this area lies at, or just below, the lower limit of precipitation given for the site. The SCS Range Site Description gives average annual precipitation of 13 to 17 inches. Greeley and Fort Lupton, the nearest U.S. Weather Service reporting stations, have long-term average annual precipitation amounts of 11. 3 and 12 . 5 inches respectively. Sandsage-Prairie Sandreed Association Reference Area A Reference Area was located on Valent Sand in section 36 just west of the rehabilitation-plot area. An area 100 by 100-feet was marked at the four corners by steel plates 10 by 12 inches staked in the center. The southeast corner is located at a position 45 feet west and 20 feet north of the southwest corner of the fenced plot area. We sampled the Reference Area, which was open to grazing by cattle in 1978, on 22 June 1978 , to determine the cover and density of sandsage and small soapweed, and the frequency of occur- rence of all plant species. Sandsage and soapweed were counted over the entire Reference Area to determine density. Their cover was measured along ten 100-foot line transects placed along the east-west coordinate at positions 5, 15 , 25, 35 , 45 , 55 , 65 , 75 , 85 , and 95 feet from the south side. Frequencies were observed by placing a 12 by 12-inch qua- drat at 5-foot intervals along the ten transects. Sandsage density was 491, which translates to 2, 139 per acre or one plant per 20 square feet, and its cover was 13% . Soapweed density was 12 , which translates to 56 per acre, and its cover was 1. 2% . Mean frequency per- centages by species are given in Table 2 , which reveals the great prevalence of annual weeds. Due to good stands of prairie sandreed and western wheatgrass , the Reference Area has better than average range condition for the six sections . 21 Table 2. Reference Area for the Sandsage-Prairie Sandreed association: Frequencies of occurrence (%) in 200 placements of a 12 by 12-inch quadrat, June 22, 1978. Perennial species: Calamovilfa longifolia 62 Agropyron smithii - A. dasystachyum 35 Artemisia filifolia 14 Ambrosia coronopifolia 10 Muhlenbergia pungens 10 Sporobolus cryptandrus 9 Stipa comata 6 Andropogon hallii 3 Allium textile 2 Eriogonum fZavum 2 Lesquerella Zudoviciana 2 Lygodesmia juncea 2 Abronia fragrans 1 Astragalus ceramicus 1 Bouteloua gracilis 1 Delphinim virescens 1 Evolvulus nuttallianus 1 Lathyrus polymorphus 1 Mentzelia nuda 1 Oenothera nuttallii 1 Phlox hoodii 1 Tradescantia occidentaZis 1 Yucca glauca 1 Argemone intermedia 0.5 Aristida Zongiseta 0.5 Asclepias latifolia 0.5 Bouteloua hirsuta 0.5 Lithospermum incisum 0.5 Mamillaria vivipara 0.5 Oenothera Zatifolia 0. 5 Opuntia fragilis 0.5 Opuntia humifusa 0.5 Physalis Zanceolata 0.5 Psoralea Zanceolata 0.5 Rumex venosus 0.5 Annual species: Chenopodium Zeptophyllum 77 Helianthus petiolaris 70 Mentzelia albicaulis 40 Eriogonum annuum 21 Cryptantha fendleri 14 Erigeron bellidiastrum 14 Cryptantha minima 1 Euphorbia glyptosperma 1 Festuca octoflora 1 Salsola kali 1 Bromus tectorum 0.5 Polygonum erectum 0 .5 Thelesperma trifidum 0.5 22 The area was grazed beginning in early June, 1978 . We understood that grazing is alternated between sections 31 and 36 from year to year. Consequently, the cover and yield of herbaceous plants on this Reference Area can be observed in odd-numbered years for comparison with reha- bilitated areas. Saltgrass-Alkali Sacaton Meadow Association This association, which is created and sustained by a high water table, is found on Loup-Boel Loamy Sands. Saltgrass identifies the outer limits of the association, but stands of alkali sacaton with baltic rush inclusions provide the greatest visible identity. The association includes a sub-association dominated by baltic rush in lower-lying patches and swales, a much larger sub-associ- ation dominated by alkali sacaton, a sub-association dominated by saltgrass but lacking alkali sacaton, and a transition-zone sub-association that includes saltgrass as an associate to the dominant prairie sandreed. Variations in depth to the water table, among other factors, thus pro- duce sub-associations that fit the description for the Soil Conservation Service ' s Salt Meadow Range Site and other sub-associations that fit, roughly, the description for the Sandy Meadow Range Site. Among the species found, most of them occur in both associations. Sandsage, except for occasional plants in the meadow transition zone, occurs only in the sandsage- prairie sandreed association. Saltgrass, alkali sacaton, baltic rush, beeplant, Canada wildrye, variegated horse- tail, licorice, goldenweed, foxtail barley, summercypress, white sweetclover, plains bluegrass, upright prairiecone- flower, common dandelion, switchgrass, tulip gentian, and salt cedar were found only on the meadow. The very weedy condition of the sandsage-prairie sandreed associ- ation extended through the meadow transition zone, but annuals were rare in the alkali sacaton dominant types . Vegetation cover on the Reference Area was determined by estimating plant cover in 100 12" x 12" quadrats on 13 September 1978 . Cover by perennial herbaceous species was 63% , cover by annuals was 0. 8% . According to the Range Site descriptions of the Soil Conservation Service, optimum plant cover is 50 to 60% for Salt Meadow and Sandy Meadow Range Sites . Total annual production should amount to 2500 pounds air dry per acre in a median year. 23 Saltgrass-Alkali Sacaton Meadow Association Reference Area A Reference Area for the meadow association was located in section 31 near the windmill. The northeast corner of the 100 by 100-foot area was placed 45 feet west of the main road and 65 feet south of the windmill road. We sampled this Reference area on 11 July 1978 , to determine the fre- quencies of occurrence of all species (Table 3) . Alkali sacaton, western wheatgrass, and blue grama were co-dominant species. Saltgrass, baltic rush, and needle-and-thread were sub-dominants. Slimleaf goosefoot was the only common annual species. This Reference Area, relative to other alkali-sacaton types of the meadow association, is a little drier and slightly less productive than average, apparently due to a heavy accumulation of lime in the soil at a depth of about 10 inches . The lime layer may restrict root pene- tration from above and water movement upward from the water table below. Section 31 remained ungrazed in 1978 . If grazing continues to be alternated annually between sections 31 and 36 , this Reference Area can be sampled for plant cover and yield for comparison with rehabilitated areas in even- numbered years . 24 Table 3 . Reference Area for the Saltgrass-Alkali Sacaton meadow association: Frequencies of occurrence (%) in 200 placements of a 12 by 12-inch quadrat, July 11, 1978. Perennial species: Sporobolus airoides 69 BouteZoua gracilis 66 Agropyron smithii - A . dasystachyum 60 DistichZis stricta 21 Juncus baZticus 20 Stipa comata 15 Calamovilfa Zongifolia 11 Cyperus schweinitgii 9 Aster ericoides 4 BouteZous hirsuta 3 Astragalus gracilis 1 Opuntia humifusa 1 Sporobolus cryptandrus 1 Lithospermum incisum 0 . 5 Tradescantia occidentaZis 0. 5 Annual species: Chenopodium Zeptophyilum 36 Cryptantha fendleri 5 Bromus tectorum 4 Festuca octoflora 2 Salsola kaZi 2 Euphorbia glyptosperma 1 Helianthus petiolaris 1 Lappula redows-kii 1 Lepidium densiflorum 1 Lupinus pusillus PZantago purshii 1 1 Cryptantha minima 0 . 5 Eriogonum annuum 0. 5 Erigeron bellidiastrum 0. 5 Lactuca scariola 0 .5 REVEGETATION Revegetation of drastic land disturbances in this sandy soil-low precipitation area will require intensive management. To define the management required revegeta- tion plots involving species, mulches, irrigation, and nitrogen fertilization were established in May 1978 on a deep sand site, Valent soil series (300 feet square) in the SW quarter of section 36 . The primary objectives of these trials were to : 1. Evaluate potentially useful forage species for seedling establishment, adaptability, and production. 2 . Evaluate straw and manure mulches for sand sta- bilization during plant establishment. 3 . Determine water requirements for establishment of native grasses . 4 . Determine the depth of sand over clay needed to sustain the native grasses . Details on each of the studies are given in appendix D. The studies are summarized below. Sprinkler Irrigation A sprinkler irrigation system was installed on one set of mulch plots and also on the species plots and sand- over-clay plots. A total of nine inches of irrigation water was applied to the soil surface to supplement the 4 inches of rainfall received over the 24 May through 6 September establishment period (Appendix E) . Since sprinkler irrigation is about 70% efficient the amount of irrigation water needed would be about 13 inches or slightly over 1 acre foot per acre to be revegetated. The only significant rainfall was about 1. 1 inch over the period of 1-8 June, 1. 6 inch over the period 30 June-7 July, and 1 . 2 inch on August 1 and 2 . 26 Germination and initial seedling establishment was assured by sprinkling with about 0 . 25 inch of water daily from 6-23 June. After seedling establishment major irrigation appli- cations were about 1 inch applied on 17-18 July and on 11 August. Two inches of water were applied over the period 22-25 August to insure adventitious rooting of the warm-season grasses. A final one inch application was made on 6 September. Without irrigation only a sparse plant cover was esta- blished on the mulched plots (Table 4) . With irrigation a good vegetation cover was established. Our present concept is to irrigate for establishment only during the first growing season. The primary reason for the timing and amounts of water applied was to insure germination and adequate adventitous rooting of the native warm-season grasses. The irrigation water used was hauled from Roggen and was assumed to be high quality non-saline water. Table 4 . Vegetation cover on 6 Septmeber 1978 as influenced by sprinkler irrigation on plots seeded 24 May 1978. Treatment Vegetation Cover - - - - % - - - - Not irrigated 3 Irrigated 44 Species Establishment and Adaptability Eighteen grass species and two legumes were seeded in individual plots on a Deep Sand Site that had been sprayed with Paraquat and rototilled twice to kill the native stands. Seeding on 24 May 1978 was with a row seeder. After seeding the plots were mulched with manure at the rate of 15 tons (dry weight) per acre. Water was applied with a sprinkling system to supplement natural precipitation. A total of 4 inches of precipitation fell during the 24 May through 7 September establishment period, this was supplemented by 9 inches of irrigation water. All species were heavily grazed before a rabbit-proof fence was completed on 7 July. All plots were fertilized with ammonium nitrate at the rate of 150 pounds per acre (50 pounds N per acre) on 10 July. 27 Certain species indigenous to the Deep Sand Site esta- blished and grew well under the intensive management (Table 5) . Blue grama grass and sand bluestem were out- standing, whereas prairie sandreed and western wheatgrass were fair. Sand dropseed produced considerable cover, much of it from volunteer seed rather than from that planted. Table 5. Stand density and herbaceous ground cover pro- duced on individual species plots seeded at the rate of 20 pure live seeds per square foot on 24 May 1978 . Plants per Herbaceous Square Foot Cover (%) 17 July ' 78 6 Sept ' 78 Species indigenous to the deep sand site. Blue grama, Lovington 4 . 6 47 Blue grama, NM 118 6 .5 47 Indian ricegrass, Paloma 0 . 4 1 Prairie sandreed, Goshen 1. 8 9 Sand bluestem, Elida 3. 8 28 Sand dropseed 0 . 3 27 Thickspike wheatgrass, Critana 1.6 4 Western wheatgrass, Arriba 5 . 9 14 Western wheatgrass, Rosana 6 . 3 10 Other species native to eastern Colorado. Green needlegrass 2 .5 4 Giant dropseed 1. 2 45 Little bluestem, Pastura 3. 8 16 Sand lovegrass 2. 0 56 Sideoats grama, NM 28 6 . 2 27 Sideoats grama, Vaugh 4 . 2 26 Switchgrass 5 . 7 82 Introduced Species Alfalfa, Travois 5 . 4 39 Cicer milkvetch, Lutana 1. 0 2 Cicer milkvetch, experimental 2 . 1 5 Crested wheatgrass, Nordan 2 .9 17 Pubescent wheatgrass, Luna 7 . 1 14 Smooth brome, Lincoln 5 .9 16 Russian wildrye 7. 5 11 28 Switchgrass and sideoats grama although not found in this area on the Deep Sand Site, established and grew well. Small amounts of these two species could be considered in seed mixes for the area. Although giant dropseed and sand lovegrass did well they may not persist on this site and are not recommended. The introduced species were all fast to germinate and were severely grazed. The introduced grasses are cool-sea- son and grew slowly in mid-summer in comparison to the warm- season grasses. At this time none of the introduced species are recommended in revegetation of extensive drastically- disturbed sand areas. Detailed information on this study is given in Appendix D. Species Established From Seed Mixture On the irrigated mulch plots a mixture of grass species indigenous to the site plus sideoats grama and little bluestem was seeded on 24 May 1978 . The species composition on these plots was measured on 18 July (Table 6) . Establishment of blue grama was outstanding. About twice as many sand dropseed plants were present as there were seeds applied. This is because there was considerable seed of this species present in the topsoil. Establish- ment of prairie sandreed, western wheatgrass and sand bluestem was fair considering the number of seeds planted. In future plantings the rate of sand bluestem seeded should be doubled. Establishment of sideoats grama was relatively low in view of past experience in seeding this species . It was difficult to distinguish sideoats grama seedlings from blue grama seedlings in the field, thus, it is believed the density of sideoats grama may be greater than indicated because some may have been included as blue grama. Stands of Indian ricegrass were sparse , this is the usual case as this species has considerable hard seed (80-95%) that will not germinate the year of seeding. 29 Observations of the plots after another growing season will give an even better estimate of the species composition and seeding rates for revegetation of large- scale disturbances. Table 6 . Density by species measured on 10 August on plots seeded to species mix on 24 May 1978. Species Seeded Density 2 Plant Density Pure live seeds/ft Plants/ft2 Prairie sandreed 10 0 . 71 Blue grama, Lovington 5 2. 36 Western wheatgrass, 5 0 . 27 Arriba Sideoats grama, Vaughn 2 0. 20 Sand dropseed 1 2 . 05 Sand bluestem 1 0 . 12 Little bluestem 1 0 . 05 Indian ricegrass 1 0 . 01 TOTAL 26 5. 77 Sod Transplanting Certain desirable species growing on the Deep Sand Site are rhizomatous (spread and sprout from underground stems) and thus might be possible to reestablish by transplanting with topsoil. These species include prairie sandreed, sand bluestem, and western wheatgrass. So an attempt was made to simulate transplanting in a topsoiling operation by using a front-end loader to scoop up sod to a depth of about 8 inches and redeposit it over subsoil. In the front-end loader operation the vegetation growing in the sand (moist at the time) did not hold together as a mat, and thus was dumped as a jumble of sand, roots, and tops . The deposited topsoil was mulched, and received 0. 8 inches of precipita- tion over the period of 25 May (transplanting date) to 5 June. On 6 June regular sprinkler irrigation was started. Very few transplants can be found. Thus it appears unlikely that many plants will be reestablished from rhizomes in topsoil. 30 Straw and Manure Mulches and Nitrogen Fertilization During seedling establishment surface stability is required to keep sand from blowing. Three different mulch treatments were applied after the sandy topsoil was furrowed shallowly and broadcast seeded. 1 . Wheat straw applied at the rate of 2 tons/acre and then crimped into the soil with the disc set straight. This treatment resulted in a stubble effect. 2 . Manure applied at the rate of 15-ton dry weight per acre. 3. Manure applied at the rate of 30-ton dry weight per acre. The straw rate is the standard rate used in revegeta- tion work. The lower manure rate was the smallest appli- cation that we thought would stabilize the site during establishment. This low manure rate was doubled for the high manure rate. Ammonium nitrate fertilizer at the rate of 150 pounds per acre (50 pounds N per acre) was applied to one-half of each mulched plot on 10 July. Plant density was nearly twice as great on the 15-ton manure rate as on the straw mulch or 30-ton manure rate (Table 7) . This was apparently because crimping in the straw buried some seed too deep. There were a considerable number of wheat seedlings established on the straw mulch plots. This wheat may have provided stiff initial compe- tition to grass seedlings, although the wheat grew slowly later in the season. The high manure rate apparently covered some grass seed too deep. Plant cover at the end of the establishment period (6 September) was comparable for all mulch treatments except the straw mulch without nitrogen treatment which had less cover than the other treatments, and the 15-ton manure treatment plus nitrogen which had statistically more cover. (Table 7 ) . This study indicates that the low manure rate with nitrogen fertilization is the most favorable. However, this was under experimental conditions where the manure was handspread. The 30-ton manure rate appears more appropriate under field conditions where spreading would not be as uniform. The manure is favored over the straw mulch in that it would probably be less expensive, intro- duces fewer grassey weeds, and supplies N and P . 31 Table 7. Plant density and cover as influenced by mulch and nitrogen treatments on plots seeded on 24 May 1978. Mulch Plants per Foot2 Vegetation Cover Treatment 18 July 6 Sept. , No N 50# N/A Straw 7. 6 25 37 Manure 15 T/A 13 . 9 38 51. Manure 30 T/A 8 . 2 37 39 In a field situation it may be that a high rate of manure would have to be applied immediately after topsoiling to keep the soil from blowing. Drill seeding and irrigation would then be started in mid-May. Seeding would be done with a specialized drill that can feed the light chaffy native grass seed and place it at a depth of about 1" in the loose sandy soil . Rodent, Broadleaf Weed and Insect Control Jackrabbits, pocketgophers, and kangaroo rats posed a persistent problem by grazing on the revegetation plots . A part of this was because the plots supported lush green vegetation when the bulk of the vegetation in the area was dry or mature. The rabbits were controlled by fencing out with 48" chicken wire buried 6" into the soil. The pocket- gophers and kangaroo rats were controlled by poisoning with strychnine-treated millet seed. Grazing by rodents should be much less of a problem on large-scale revegetation projects. If necessary, pocket- gophers could be controlled by applying strychnine poison through a mechanical burrow maker. Close monitoring would have to be maintained for rabbit damage. If damage to seedlings is severe (this would probably require a much greater rabbit population than is now present) fencing might be required. Broadleaf annual weeds will pose a major problem in any revegetation program involving topsoil and use of straw or manure as mulches. This is because the topsoil, straw, and manure usually contain considerable numbers of viable 32 weed seeds. On the experimental plots the broadleaf annual weeds were controlled by a spray application of Bromoxynil at the rate of 1/4-pound per acre on 7 July. This herbicide is selective for broadleaf plants and will not affect grass seedlings (2,4-D will affect small grass seedlings) . The Bromoxynil damaged the weeds but did not kill them so on 13 July the plots were resprayed with Bromoxynil at the rate of 1 pound per acre. This application killed all the weeds except pigweed. The pigweed was later hand pulled on the plots, but in a large scale operation, it probably would be sprayed with 2 ,4-D after the grasses have reached a non- susceptible 4-leaf stage . The plots were sprayed with malathion for control of an abundant leafhopper population on 14 July. The entire range (several sections) was sprayed for grasshopper control in late July (probably with Sevin) . On extensive revegetation projects a close watch should be maintained for major insect problems during the year of establishment and control measures taken if needed. Depth of Sand over Clay For reclamation it will be expensive to move quantities of sandy topsoil and subsoil for placement over spoil which will largely be clayey shales from the overburden above the coal. We need to know the depth of sand needed above the clay to sustain the native plants adapted to the sand. The problem is critical because the depth of sand must be enough to prevent water logging, and winterkill . On the other hand, clay under a reasonable depth of sand may hold water and fertility for greater production than can be obtained on the existing deep sand . To investigate this plots were put in with different depths of sand over clay shale. The treatments were: 1 foot of sand topsoil over clay shale 2 feet of sand (1 foot of topsoil over 1 foot of sub- soil) over clay shale. 3 feet of sand (1 foot of topsoil over 2 feet of sub- soil) over clay shale. 33 The clay under each plot was diked on the borders so that water would not run off of the sand-shale interface . The plots were seeded to the native grass mix, mulched with manure and irrigated for establishment. No differences were apparent among these depth-of- sand plots during the first growing season using sprinkler irrigation for establishment. It will probably take several growing seasons under natural precipitation before conclusions can be drawn from these plots. In the mean- while our assumption is that a minimum of three feet of sand are required over clay to support the diversity and productivity of plant species native to the deep sand site . It is suggested that spoil material to be covered with sand be contour ridged, furrowed or pitted in such a way that moisture penetrates into the spoil rather than moves off at the sand-spoil interface. Grazing Management of Rehabilitated Areas Although sand stabilization and prevention of wind erosion is the most immediate goal of rehabilitation, live- stock grazing is the primary use for which disturbed areas will be rehabilitated. The goal for management is sus- tained high forage production and sand stability with a vigorous stand of forage species and a minimum amount of weeds and sand sage. At present, the sand appears to be stabilized more by annual weeds and sand sage than by forage species, and it would be unfortunate if rehabili- tated areas were deteriorated by grazing to an equivalent weedy condition. With irrigation and fertilization in the first year, thick stands of native grasses can be established and rooted deeply to stabilize the sand. Thereafter, the plants must survive without irrigation , which means that competition among plants will increase and eliminate weak and shallow- rooted individuals. For example, we expect a reduction in the density of sand dropseed, which is a pioneering perennial grass, as deeper-rooted bunchgrasses increase in size and rhizomatous species increase in density. To attain the goal of high forage production and sand stability, we need to maintain a good mixture of short and tall grasses , the balance of which is readily influenced by season and intensity of grazing. 34 These factors bring to mind questions such as : when should grazing begin after rehabilitation, how should fences be placed to control grazing, what degree of utili- zation can be permitted without harm to plant vigor and sand stability, and what can be done to replace the forage lost during mining and rehabilitation? There is more than one way to resolve those questions, but the final plan should provide mutual understanding between the company, the ranchers, and the Soil Conservation Service. Consider, for example, the question: when should grazing begin after rehabilitation? Unless regulations require protection for several years, the best answer is a composite of biological, economic, and logistical factors. Because the management and durability of rehabilitated areas needs to be developed and demonstrated at an early time, we would like to propose the initiation of carefully controlled grazing in late summer or fall in the year after seeding. But, grazing of newly seeded areas in common with larger areas of either existing range or of older rehabili- tated range is hazardous because the newstands attract grazing animals and, thus, suffer excessive grazing, which. reduces the tall-grass component. These factors suggest an intensive plan of fencing each seeded parcel separately and of keeping it separate for about four years before com- bining the parcels into larger units. Economic factors must be considered at this point because the grazing obtained, when the annual increment of land rehabilitated is expected to be about 30 acres, would not justify much cost in fencing and water development. With such an inten- sive plan, justification would derive largely from the value of management experience and demonstration of vege- tative stability. A less intensive plan would involve fencing areas of , say, 160 acres or more to exclude livestock during mining and rehabilitation. Grazing then would not begin until the whole paddock had been rehabilitated and the newest parcel was fully stabilized. Furthermore, the area should be mowed in early spring to a stubble height of about 6 inches to promote uniform distribution of grazing. With this plan, the value of management experience obtained is diminished and delayed, and the value of lost grazing increases, with increase in size of area so treated. Utilization standards should be developed as rehabili- tated areas are placed under grazing. Those standards should specify the height and/or amount of herbage that must not be grazed -- that is, the amount of herbage needed to maintain sand stability, vigor of forage plants, and balance between short and tall grasses . We can provide only preliminary standards, as follows : the average height 35 of tall grasses should be at least 7 inches, the biomass should amount to at least 600 pounds per acre dry weight, and the herbaceous cover should amount to at least 25% . Forage lost during mining and rehabilitation can be compensated in cash or kind. The question is considered here because people often want to consider alternatives, especially those that might have lasting values and pro- duce spin-off benefits in applied technology. The alter- native considered is that of replacing forage lost by improving adjacent ranges . We think the prospects of improving adjacent ranges by weed control and fertili- zation is very good. The technologies needed are known, but methods and materials should be examined in plot trials to determine appropriate rates and cost effective- ness. Section 36 , which is state owned but grazed under lease in alternate years, would provide an excellent location for such trials. Treatments applied in the fall 1978 and spring 1979 could be evaluated in 1979 when livestock would be excluded. 36 APPENDIX A SOIL SERIES DESCRIPTIONS Two soil series cover most of the Study Area. They occur on the deep sand plains with slopes ranging from 0 to 15 percent. Soil series identified and mapped on the deep sand plains portion of the Study Area are : (1) (1) Osgood (variant) , (2) Valent, and (3) Vona-like. Since the Vona-like soils were found in only one small area they were not sampled. The Osgood and Valent soils were pit sampled and profile characteristics recorded at duplicate sites for each of the series (a profile description of each of the latter two soils follows) . All samples were taken in Sec. 36 , T. 3N . , R. 64W. Locations of the pit sites are shown on the accompanying soil map. The Sandy Meadow portion of the Study Area was not pit sampled, however, several small core samples were examined. Considerable variation was found to exist within short distances in these poorly drained soils . This portion of the Study Area was described as Loup-Boel loamy sands 0 to 3 percent slopes, in the South Weld County Soil Survey Report (unpublished) . Profile descriptions of the Loup and Boel soil series, as given in the South Weld County Soil Survey Report follows. Even though the profile descriptions probably are not typical of the soil condi- tions found in the sandy meadow, there is sufficient similarity so that the descriptions would give an idea of the general profile characteristics of these soils. 37 Osgood Series TAXONOMIC CLASSIFICATION: Loamy, mixed, mesic Arentic Ustollic Haplargids. The Osgood soil as mapped in the study area is des- cribed as a "variant" of the typical Osgood series . The typical Osgood soil as mapped in the south Weld County soil survey has a thicker and finer textured subsoil than the Osgood variant as mapped in the Study Area. As mapped they consist of deep, well-drained soils that formed in wind-laid sands. They occur on smooth plains that have slopes of 0 to 3 percent. Osgood soils are usually adjacent to or near Valent soils which do not have a B horizon. Profile description of Osgood sand, variant, 0 to 3 percent slope, as obtained on the study area (3400 feet west and 100 feet south of the northeast corner of Sec. 36 , T. 3N. , R. 64W. ) . (Site #1 on soil map. ) All -- 0 to 5 inches; brown (10YR 5/2) sand, dark grayish brown (10YR 4/2) ; moist; single-grained; loose; neutral; gradual smooth boundary. Al2 -- 5 to 18 inches, brown (10YR 5/3) sand, dark grayish brown (10YR 4/2) moist; single-grained; loose; neutral; gradual wavy boundary. A3 -- 18 to 32 inches; brown (10YR 5/3) sand, dark brown (10YR 4/3) moist; single-grained; hard when dry, friable when moist; neutral; gradual smooth boundary. B&A -- 32 to 44 inches; brown (10YR 5/3) sand, dark brown (10YR 4/3) moist; massive; hard when dry, friable moist; neutral; clear smooth boundary. B2t -- 44 to 49 inches, brown (10YR 5/3) loamy sand; dark brown (10YR 4/3) moist; moderate coarse prismatic parting to moderate medium subangular blocky structure; hard, friable; neutral ; clear irregular boundary. C -- 49 to 60 inches; pale brown (10YR 6/3) loamy sand, brown (10YR 5/3) moist; massive; slightly hard dry, very friable moist; slightly alkaline. 38 Valent Series TAXONOMIC CLASSIFICATION: Mixed, mesic, Ustic Torripsaments The Valent soils consists of deep, excessively-drained soils that formed in wind-laid sands. They occupy gentle plains that have slopes of 0 to 9 percent. Valent soils are near the Loup-Boel and Osgood soils . Loup-Boel soils are poorly drained. Osgood soils have B horizons. Profile description of Valent sand, 3 to 9 percent slope, 900 feet north and about 2000 feet west of the southeast corner of Sec. 36, T. 3N. , R. 64W. (Site #4 on soil map) . Al -- 0 to 5 inches; brown (10YR 5/3) sand, dark grayish brown (10YR 4/2) moist; single-grained; loose; neutral; gradual smooth boundary. AC -- 5 to 13 inches; brown (10YR 5/4) sandy, dark grayish brown (10YR 4/3) moist; single-grained; loose; neutral; gradual smooth boundary. C -- 13 to 60 inches; brown (10YR 5/4) sandy, dark grayish brown (10YR 5/3) moist; single-grained; soft, loose; neutral. 39 Loup Series TAXONOMIC CLASSIFICATION: Sandy mixed, mesic, Typic Haplaquoll The Loup series consists of deep, poorly drained soils that formed in sandy alluvium. Loup soils occur primarily along drainages in the sandhill area and have slopes of 0 to 3 percent. Loup soils are near the Boel and Valent soils. Boel soils are stratified and somewhat poorly drained. Valent soils are excessively drained and have a light colored surface layer. Profile description of Loup loamy sand from an area of Loup-Boel loamy sands, 0 to 3 percent slopes. 01 -- 2 inches to 0, undecomposed organic material, chiefly grasses, sedges, and roots. Al -- 0 to 16 inches, very dark grayish brown (10YR 3/2) loamy sand with few fine distinct reddish brown (5YR 5/4) and dark gray (N4/) mottles, black (10YR 2/1) moist; weak fine granular structure; soft, very friable; calcareous; moderately alkaline (pH 8 . 2) ; diffuse boundary. Cl -- 16 to 40 inches, light brown gray (10YR 6/2) loamy sandy with few fine distinct yellowish brown (10YR 4/4) mottles, grayish brown (10YR 5/2) moist; weak fine granular structure; soft, very friable; calcareous; moderately alkaline (pH 8 . 2) ; gradual wavy boundary. C2 -- 40 to 60 inches, light brownish gray (10YR 6/2) sandy loam with common medium distinct yellowish brown (10YR 5/6) and gray (10YR 5/1) mottles, grayish brown (10YR 5/2) moist; massive; hard, friable; calcareous; moderately alkaline (pH 8 . 0) . Typically these soils have free carbonates at the surface . The A horizons has value of 3 or 4 dry, 2 or 3 moist and chroma of 1 or 2 . The C horizon, to a depth of 40 inches or more, is a loamy sand or sand. 40 Boel Series TAXONOMIC CLASSIFICATION: Sandy mixed, mesic, Fluroquentic Haplustoll The Boel series consists of deep, somewhat poorly drained soils that formed in stratified sandy alluvium. Boel soils occur primarily along drainages in the sand- hill area and have slopes of 0 to 3 percent. Boel soils are near the Loup and Valent soils. Loup soils are poorly drained and are mottled at the surface. Valent soils are excessively drained and have a light colored surface layer. Profile description of Boel loamy sand from an area of Loup-Boel loamy sands, 0 to 3 percent. Al -- 0 to 14 inches; grayish brown (10YR 5/2) loamy sand, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, loose; calcareous; moder- ately alkaline (pH 8. 2) ; gradual smooth boundary. Cl -- 14 to 31 inches; pale brown (10YR 6/3) loamy sand stratified with thin lenses of sandy loam, brown (10YR 5/3) moist; few fine faint light yellowish brown (10YR 6/4) moist and yellowish brown (10YR 5/6) moist mottles; massive; soft, very friable; calcar- eous; moderately alkaline (pH 8 .4) ; diffuse wavy boundary. C2 -- 31 to 60 inches; very pale brown (10YR 7/3) loamy sand stratified with thin lenses of sandy loam and sand, pale brown (10YR 6/3) moist; common medium sized distinct yellowish brown (10YR 5/8) moist, brownish yellow (10YR 6/6) moist and gray (10YR 5/1) moist mottles; massive; soft very friable; calcareous; moderately alkaline. Typically these soils have free carbonates at the surface . The A horizon has value of 4 to 5 dry, 2 or 3 moist and chroma of 1 or 2 . The C horizon has value of 6 or 7 dry, 5 or 6 moist and chroma of 2 or 3 . It is a loamy sand or sand. 41 APPENDIX B. LABORATORY CHARACTERIZATION OF SOILS. Soil Name Horizon Depth pH J c.c. 2/ t O.M. 21 NO 1-N P, K� Zn5/ Mn5/ Cu5/ ne5 (in.) -PpM _/ PPm PPm PPm - PPm - PPm - PPm Osgood All 0- 5 6.5 2.6 0.7 46 5 231 0.6 3.8 0.4 1'.5 site 41 Al2 5-18 7.6 0.2 0.5 1 3 90 0.1 0.8 0.4 9.2 A3 18-32 7.6 0.4 0.4 3 90 0.1 1.2 0.4 10.3 B & A 32-44 7.5 0.2 0.4 1 95 0.1 0.6 0.3 '.0 B2t 44-49 7.2 0.2 0.5 1 146 0.1 0.4 0.3 9.9 C 49+ 8.0 0.2 0.2 1 60 0.1 0.4 0.4 1.0 Osgood All 0- 5 6.8 0.2 0.9 1 6 115 0.8 2.9 0.7 24.8 site 44 Al2 5-17 7.4 0.2 0.5 <1 2 105 0.1 1.0 0.5 8.6 A3 17-27 7.6 0.1 0.5 1 136 0.1 1.1 0.7 7.1 821tb 27-37 7.3 0.2 0.5 1 226 0.2 1.0 0.6 e.1 822tb 37-47 7.3 0.2 0.3 1 152 0.2 0.7 0.4 7.6 Cb 47+ 7.7 0.2 0.3 1 79 0.1 0.9 0.4 4.3 " Valent Al 0- 5 6.4 0.4 0.7 5 8 74 1.2 3.2 0.4 25.6 Site 04 AC 5-13 7.1 0.2 0.4 2 64 0.3 0.8 0.4 11.7 C 13+ 7.4 0.1 0.2 2 50 0.2 0.8 0.3 7.8 Valent Al 0- 4 6.6 0.2 0.9 2 6 157 1.7 4.1 1.6 26.8 site 02 AC 4-14 7.1 0.2 0.4 3 91 0.2 0.7 0.3 11.4 C 14+ 7.9 0.2 0.2 1 93 0.1 1.0 0.3 5.8 Osgood Al 0-10 6.8 0.4 0.6 4 107 0.7 2.7 0.5 22.8 Sec. 31 81 10-14 7.2 0.7 0.6 143 0.5 0.5 0.5 9.3 B21t 14-22 7.3 0.3 0.6 230 0.2 0.2 0.5 63 22-28 7.2 0.3 0.6 192 0.2 0.2 0.4 7.5 Cl 28-36 7.4 1.0 0.4 93 0.2 0.6 0.4 6.4 C2ca 36-60 0.1 42 0.2 0.5 0.5 4.6 Osgood Surface Sou. 31 Composite 7.4 0.2 0.7 92 0.6 2.7 0.6 16.4 Valent Surface 7.5 0.4 0.7 9 118 1.0 4.1 0.5 11.3 Soc. 25 Composite Valent Surface 7.5 0.2 0.5 5 72 0.6 2.7 0.6 14.4 Sec. 36 Composite Osgood Surface 7.1 0.2 0.7 5 86 0.7 3.8 0.5 12.9 Sec. 26 Composite Loup-Boel Surface 7.3 0.5 1.0 7 108 1.0 5.2 0.6 1[.4 Sec. 31 Composite Osgood Surface 7.0 0.2 0.7 7 84 1.0 3.4 0.6 13.8 Sec. 35 Composite Valent Surface 6.7 0.2 0.6 6 65 0.8 2.9 0.4 21.7 Sec. 36 Composite 1/ pH determined with a combination electrode pH meter on a saturated extract. y Soluble salts were determined on a filtered saturation extract using a solu-bridge and reported as mnhos/cm. 3/ Organic matter was determined calorimetrically by the wet oxidation-potassium dichromate-sulfuric acid method. t/'Nitrate-nitrogen was determined by the chromatropic acid method. 5/ Extractable phosphorus, pntassiwn, u1nr, Iron, topper. and manganese were determined by the aimum um Iarhonate-(1111'A) owl hod. 42 APPENDIX B. Continued. Particle Size Analysis 1 Soil Moisture Data / Soil Name Horizon Depth % bar (in.) Sand Silt Clay 1/10 1/3 15 Osgood All 0- 5 89 8 3 5.1 2.8 1 .5 Site #1 Al2 5-18 92 4 4 A3 18-32 93 3 4 B & A 32-44 93 2 5 B2t 44-49 83 5 12 16.3 10.4 5.4 C 49+ 87 5 8 Osgood All 0- 5 87 9 4 6.0 3.7 1.8 Site #3 Al2 5-17 92 5 3 A3 77-27 92 4 4 B21tb 27-37 89 2 9 B22tb 37-47 91 1 8 8.2 6.2 3.3 Cb 47+ 93 1 6 Valent Al 0- 5 93 5 2 4.3 2.7 1 .5 Site #4 AC 5-13 95 3 2 C 13+ 97 2 1 2.7 1.5 1 .1 Valent Al 0- 4 92 6 2 5.7 3.0 1 .8 Site #2 AC 4-14 94 3 3 C 14+ 95 3 2 4.0 2.2 1 .4 Osgood Al 0-10 89 6 5 Sec. 31 81 10-14 91 3 6 B2t 14-22 84 6 10 B3 22-28 82 8 10 Cl 28-36 87 7 6 C2ca 36-60 88 6 6 Osgood Surface 89 9 2 4.3 2.9 1 .8 Sec. 31 Composite Valent Surface 93 6 1 3.8 2.4 1 Sec. 25 Composite Valent Surface 94 5 1 3.9 2.0 1 .3 Sec. 36 Composite Osgood Surface 90 9 1 4.5 3.2 2.0 Sec. 26 Composite Loup-Boel Surface 89 9 2 6.6 3.7 2.4 Sec. 31 Composite Osgood Surface 90 9 1 6.3 3.1 2.2 Sec. 35 Composite Valent Surface 89 9 2 5.2 2.2 1 .6 Sec. 36 Composite I/ Particle size determinations were determined by the hydrometer method and sand sieve analyses on selected samples. �/ Moisture tensions were determined using the pressure plate method. 43 a q en CO N N C.) oo\° 4-4 CO LC) U) 4.0 In i C V N It) N •r O1 O U) l"---- >. LI- a) N- LC) O C . O Is V V V rrd- E 3 -1--- N CO to V C -O N N en r-- co a) N N CO N V) 5 o" v in O3 N N 5- (O M N M 4z1- O r r r r- (_) a) > N V an V l0 N i >. (O r r O r- 0 U .C 4-) Ln LC) LL') C}' O_ I I I I Q O O O O v a C .H +) C O 0 N r- r U s ¢ ¢ ¢ a O x na H Q M it N a a it it Q Z Z O o 0) 1-r N 4-) 4) [a] O J-' O +) C 1) C 1) A+ O -.i O -H v -.1 N -H a r CO (n CO U) r Ill r U) VI 0 0 > > 44 j I _ - - i• 9 : - - : ,2e , 4 : aaooe a 642 . 22 . 2. . .4o < eoa vo _ o g Ei N eee z 4 _ r 5r ., gl g ., g z = m mm22 e a O m �, e _ . 2 .t- Al0 u W8 " e nn ^ n „ _ ^ 0 € e M d - - o .444 2 .2 2 .2 .e .2O y m " _ , - u m e F ---4 " m - - ' " " _ - - W " bY ^ 0 n e e O - - - " - - - _ " " at .-I tW E _ - - c - w " " " 0 0 . . F _ \ ,aa O � - w o " CA L L.4 co a M s oo o e a v m o w o 01 ' e a - 4 F i - - s 4 5-g O A a€124 Q CJ m _ a - M zin w Wra, W 5 w 4 W A o a 2X22 er ee ^ ^ a S G] A ry ,“ - 45 odoo 6000ao a - - ^ - - k : 2 x s $ m ^ r, c., t.., 000 0 0 7 ar, a a - ^ - - A r a, ^ a, a, r a, a, 3 - , r 6 e 6 r 6 e 6 .6 ^ m 6 e a a .o e0. 6 e 1 - - �, a o a m .., e - m .- a aam a a - a z H tH € _ o - aa .� m e aaa - m o 0 M ,. N. e a m N. - - _ - m e 6 m e ^ e a N n. a o - - e ^ a _o - -- en_ en_ .o a. W 6 a - a - - o - - _ 6 a a a e m a - +p N U t w ^ ^ mm .- W OO a 0; 040 _4. .- 0, r, .,- 48 48 m v 2 0 g2 m ^ m ^ ^ ^ ^ ^ m ^ ^ a ^ m ^ ^ ^0 in en ^ N. pC 4) a 0 0 U a • O L) x W W g v - ._ '-a O - CA E u T ✓ 7. r „2 2 o ^ E Qa ,? r , r - -s v, _, a � r B 2, u. P a u E m < ' 8 _ 0 04 0 41 0 8 0 8 0 a m 0 0 0 04 0 m e ��I • 46 C I Ol to M C1' r•-• H 1 r-- r O 0 0 a-- 00 O H I N J I 0 CO LO t0 CO LO Cr, U W 0 1 rO O N N I 1 1.0 CO CO 01 N I. N O LL N CO Z I J H I N N In V) V) In J U -ZO N E N N r-- r r CV e �, H d r O O O CO H a O Y , rr- Ol V CO T CO U) (� 1 LO N. N. t0 ^ N CO N N H 1 1 H I N + I ^ oa CO Ln N N 1/40 CO t0 I co en CF Z I I C7 Z L HI V) 1 1 IC I 01 CO 01 Cr) NO e N �] 0 O O Z I. N U) V e LO e �' •W] 1 t0 C V LC) O a., to N O O co co O O O co N I co O C O N C t0 N 0 I 2 I co M N r N O H E +;(11 L -C t L i-I O O O O O C o CN U) 0 0 0 v) 01 v' o) X U J N t t r _C N Z• N. ‘.0t0 N. p I� 0 RI b +• Z CO C C O O N V: 0 vl 1.1 Ei 00 .rI inN 0 U Ln Ln a LO• V• CO• M , E C N O N CV O • W h C O O O O co r-- r r .- I- C) U N I r N 0 I UH U I V co in N N in �y I N N CO M •- r N N F] M O N. M LO •-- I-4 = r 01 a IC E I r N e to co p N e- 4-3 _c d Y more zi III L CV C- t0 co co ^ v 0 tF. WN i-I O N V VD CO O ^, a 1 CL I I I 1 1 I I O N V LO OJ CD N 47 APPENDIX D REVEGETATION PLOT LAYOUT An area 300 feet square, located in the SW quarter of Section 36, T. 3N. , R.64W. , was fenced to exclude livestock and mowed to mulch the sand sage in preparation for revege- tation trials. This is a Deep Sand Range Site with sand sage providing the dominant aspect and prairie sandreed, western wheatgrass, blue grama, Indian ricegrass, and needle-and-thread providing primary forage. The soil series on the experimental area is the Valent. The deep sand was derived from wind action in the past. Consequently, prompt stabilization and revegetation must follow any dis- turbance. 48 PLOT LAYOUT The plot layout includes four sets of plots, which are illustrated below. The three sets of plots along the south side are served by the sprinkler-irrigation system. Most of the border areas surrounding the plots were disturbed when preparing the plots; consequently, they have been mulched with straw and seeded with a mixture of native grasses. All plots except those for species adaptability were seeded with a mixture of native grasses. X X X X _-X >C N Mulching trials, x x nonirrigated x x >c Mulching trials, X irrigated Species Depth of sand adaptability over clay x X k Water tanks i< OO f( x X X x Road 49 SPECIES ADAPTABILITY Twenty grasses and three legumes were selected for evaluation of adaptability and performance on the deep sand. Most of the grasses are selections of species native to deep sands in Colorado. The plots were prepared by spraying with paraquat, rototilling, fertiliz- ing with superphosphate at 40 pounds of P/acre, rolling, leveling, drilling with a cone seeder, and mulching with manure. Seeding was completed on May 24, 1978. Each plot includes 5 rows spaced 12 inches apart. The plot layout is illustrated below, and the species are listed in more detail on another page. 1 Rus, wildrye 24 L. Blue grama 47 Ricegrass 2 Blue grama 25 R. Western w. 48 V. Sideoats grama 3 Crested w. 26 Pubescent w. 49 Milkvetch 4 Smooth brome 27 A. Western w. 50 Crested w, 5 Switchgrass 28 L. Milkvetch 51 Sand lovegrass 6 L. Milkvetch 29 Sand lovegrass 52 Blue grama 7 Thickspike w. 30 Sand bluestem 53 Sand bluestem 8 R. Western w. 31 Needlegrass 54 Thickspike w. 9 Little bluestem 32 Giant dropseed 55 R. Western w. 10 A. Western w. 33 Alfalfa 56 Pubescent w. }1 Sand bluestem 34 V. Sideoats grama 57 Sand dropseed 12 L. Blue grams , 35 Little bluestem 58 Alfalfa 13 V. Sideoats grama 36 Ricegrass 59 Switchgrass 14 Ricegrass 37 Sideoats grama 60 Little bluestem 15 Milkvetch 38 Blue grama 61 Smooth brome 16 Giant dropseed )9 Milkvetch 62 Sideoats grama 17 Sideoats grama 40 Switchgrass 6 L. Milkvetch 18 Sand lovegrass 41 Sandreed 64 Giant dropseed 1,/ 19 Sand dropseed 42 Smooth brome 65 Needlegrass 1� 20 Sandreed 43 Thickspike w. 66 Rus. wildrye 21 Alfalfa 44 Sand dropseed 67 Sandreed 22 Needlegrass 45 Crested w. 68 A. Western w. 23 Pubescent w. 46 Rus. wildrye 69 L. Blue grama The plots are not drawn to scale, but measure 5 by 15 feet. 50 rci ID \O\OO \NO `nw �\O cO� T� �� u01 2 -(4\;g(-4.)- -- r�i cg C' (<,,...,1 (\1 r�-_t4.).\(.9 N o vl 4, rn orJ r1 N 4, 0 ri O CJ7 N c`"h[`r—I fT O\\D c+\1p O D..c,-)c`\4-4-CO N r-1 04 N r-1 r--I r-I :--I rf H .H r-I (\,• r-I o? r P •rf O\C\ N\O CO. 4 C\ul O\C\ O\OJ\O C1 O\ON G\C\ fft O\ 1 C\C% C\CO CO C\ ON C\ON ON ON C\C\ ON ON C\T ON g8oL` Fit. 1Nti^�\ c9,rnrn 8 TR8«) t' (' O E. I-1 -4 U =I (o +3 N N 0 Q 0 Q 0 cd CO t O Ca7 -cl 0) a) 'g t!1 u) 3 21-4 t7 I I—I t 0 lc�d E • O cd b..) 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O W U O i d li0 l,J U 0 :I L) 'Y1 'L7 {-) l .C U) 'C1 U r-I (d cd O O 0 �J •}1 .ri a) •r{ t,',, 3 u) in (.1 . .7 O g V O 0 $4j r'i O .i C: G 0 f: t7 C f{ q, r-1 r I r-i r1 a a 2 9 0 F-! H f, H i C) .;.-+ (;3 fd l T Ql I -1 O O O G U U ' ' li 1 a, i> c 1 ��,q. I r) r., +)3 a +' +) fi f{ 2 f{ •ri 5 0 f-1 04 O OC N O C fa f`+ •rI r-i Q� QO �n3 Z ro 'd O O ' Q) 8, R. c$ a�•' a(l. C',1 <<<° f� ' ao+' r i� l�n V .r-1 y 6 lY1 O Q C.'] (�) 4 4'• . U r•-1 C') (n4' 'r\\•0 N-CO 0 Cr s -I N C'1--.i irs.\D ('-CC O\ O r--I N cl ''' r--i r—I Hr-4 r-I r—i r—i r—i r-I r f N N c\I N i 51 MULCHING TRIALS--IRRIGAihD Although prompt revegetation can not be assured under the climatic conditions at this site without irrigation, which helps control wind erosion, mulching treatments are proposed as part of the seeding procedure for surface stabilization of wind-blown sand. Straw and manure are included as mulching materials because they are readily available to the site. In plot preparation, one foot of topsoil was removed and replaced. Then the plots were: (a) fertilized with superphosphate at 40 pounds of P/acre to improve seedling vigor and rate of establishment, (b) disced lightly to roughen the seedbed, (c) seeded by broadcasting a mixture of native-grass seed (Prairie sandreed, western wheatgrass, blue grama, indian ricegrass, sand dropseed, sand bluestem, little bluestem, and sideoats grama), and (d) mulched with either manure at 15 tons/acre (dry weight), manure at 30 tons/acre, or straw at 2 tons/acre. The straw was embedded by discing with discs running straight ahead. These three mulching treatments were replicated six times; however, three of the replications were treated with paraquat at 2 pounds of active ingredient/acre before removal and replacement of topsoil, to kill as much of the existing vegetation as possible. These plots, which are shown as shaded areas in the plot diagram, are identified as dead-sod topsoil; whereas, the plots not treated with 1 paraquat are identified 13 as live-sod topsoil. Straw Manure-15 Manure-30 Maximum transplant- .- ti4-1ing responses of existing 2 $ lUI14 vegetation, especially 8, of the important grasses Manure-30 ° Strait S Manure-15 ° prairie sandreed and bo b western wheatgrass, should N m be obtained on live-sod 3 a 9 15 topsoil. Manure-15 Manure-30 Straw a The plots were seeded and mulched on May 24, 1978. 4 10 16 Manure-15 Manure-30 Straw 5 11 F 17 i O Straw -1-3 Straw ' + Manure-15 o' o z' '8 m o 1 I N 6 j 12 18 N 20. Manure-30 Manure-15 Manure-30 F- x-,„..'---i$ 52 MULCHING TRIALS--NONIRRIGATF.D Plots tilled and seeded can be compared with native vegetation in this set of plots. Tilled plots were prepared by spraying with paraquat, roto- tilling, fertilizing with superphosphate at 40 pounds of P/acre, discing, broadcasting seed of native grasses, and mulching with manure at 15 tons/acre or with straw at 2 tons/acre. Straw-mulched plots were fertilized with ammonium nitrate at 50 pounds of N/acre. These plots were seeded and mulched on May 24, 1978. 1 5 9 Manure Straw 2 10 Straw Native Manure 3 11 Manure Manure 4 6 12 Manure 7 Native 3traw Native zo' 8 Manure N --30 --- 1 53 DEPTH OF SAND OVER CLAY In the event of open-pit mining in this area, engineering procedures prescribe the opening of a new section and closing of an old section by (a) removing and stocking one foot or more of topsoil sand, (b) pushing the remaining sand into the bottom of the old pit, (c) pushing clay (shale) over the sand, and (d) spreading the topsoil sand over the clay. Conse- quently, we need to know how much sand is needed above the clay to sus- tain native plants. The problem is critical because the depth of sand must be enough to prevent water logging and permit enough rooting depth to give the tall grasses a competitive edge over the short grasses. On the other hand, clay under a reasonable depth of sand should hold water and fertility for greater production than can be obtained on the existing deep sand. To meet this objective, we removed sand to depths that permitted refilling with one foot of clay (which was border diked to prevent per- colation away from the plots) , zero to two feet of subsoil sand, and one foot of topsoil sand. Replicated plots would have been excessive and difficult with this layering procedure. The alternative was rela- tively large plots for more realistic sub-ecosystems. Viewing the plots from west to east, sand depths above clay are one, three, and two feet, as shown below. The plots were seeded and mulched with manure on June 3, 1978. The clay was obtained from a pit into the Laramie forma- tion located mile south of Highway 52 and four miles west of Fort Lupton. The clay was packed very firmly into the bottom of the plots by running over it with a front-end loader. 451 One foot Three feet Two feet N S 54 APPENDIX E. PRECIPITATION AND IRRIGATION Since planting on 24 and 25 May, we have had a total of 4 . 03 inches of precipitation and have applied 9 .2 inches of water for a total of 13.25 inches as of 6 September. Precipitation amounted to 1. 21, 1. 29, and 1. 28 inches in June, July, and August, respectively. Those amounts were 88% of normal based on long-term records at Fort Lupton, or 97% of normal by Greeley records. Date Precip. Irrigation Total Comments May 24 Planted Species plots. 25 Planted Mulch plots. 31 0.34 0.34 June 1 0.24 0.58 2 0.03 0.61 3 Planted Depth-of-sand plots. 5 0.17 0.78 Milkvetch and alfalfa up. 6 0.19 0.53 1.50 8 0.16 0.33 1.99 9 0.08 2.07 13 0.34 2.41 Water tanks filled on 12th (Fill 2) -. 14 0.25 2.66 15 0.35 3.01 Fill 3 16 0.33 3.34 17 0.25 3.59 18 0.25 3.84 19 0.25 4.09 Fill 4 20 0.25 4.34 21 0.25 4.59 22 0.25 4.84 23 0.35 5.19 Fill 5 30 0.42 5.61 Most of 0.42 rain about 26 June. July 6 0.84 6.45 All 0.84 rain on 5 July. Rabbit fence up. 7 0.34 6.79 Hail damage with 0.34 precip. on 6 July. 10 0.02 6.81 11 0.25 7.06 17 0.40 7.46 18 0.60 8.06 Fill 6 Aug. 3 1.20 9.26 Rain from storms on 1 & 2 Aug. Drizzle. 10 10 0.05 9.31. 11 0.95 10.26 Fill 7 on 14th (could have been later) 22 0.03 0.47 10.76 Began watering -£or new rooting. 23 0.47 11.23 24 0.50 11.73 Fill 8 25 0.50 12.23 Fill 9 on 26, 27, or 28. Sept. 5 0.02 12.25 6 1.00 13.25 Fill 10 ordered for 7 Sept. 20 1.00 Oct. 21- 23 1.90 WATER RESOURCES AND IMPACT EVALUATION FOR A PROPOSED MINING SITE WELD COUNTY, COLORADO WATER RESOURCES AND IMPACT EVALUATION FOR A PROPOSED MINING SITE - WELD COUNTY, COLORADO Submitted to ADOLPH COORS COMPANY GOLDEN, COLORADO by D. B. McWhorter, Associate Professor N. Ortiz, Assistant Research Professor Agricultural and Chemical Engineering Department Colorado State University Fort Collins, Colorado November, 1978 TABLE OF CONTENTS Part Page Conclusions and Recommendations 1 I Introduction 4 II General Description of Hydrology and Geology 4 A. Climate 4 B. Geology S C. Water Resources 7 III Pre-Mining Subsurface Hydrology and Water Quality in Detailed Study Area 8 A. Geology 8 B. Characterization of Hydraulic Properties of Aquifers 10 C. Piezometric Surface 25 D. Water Quality 29 E. Summary of Existing Situation 35 IV Subsurface Hydrology and Water Quality During Mining . . 36 A. Pit Inflow Estimates 36 B. Orawdown of Piezometric Surface Due to Pit Inflow . 43 C. Quality of Mine Inflow 45 V Post-Mining Hydrology and Water Quality 46 A. Post-Mining Flow Patterns and Hydrology 46 B. Post-Mining Water Quantity and Quality 48 VI Acknowledgements 49 APPENDIX A - Well Construction and Location 50 APPENDIX B - Calculation of Hydraulic Coefficients . . . 66 APPENDIX C - Data 85 APPENDIX D - Approximate Location of Existing Wells . . 99 ii LIST OF FIGURES Figure Page 1 Mean monthly precipitation at Greeley, 1952-1976 6 2 Mean monthly precipitation at Fort Lupton, 1952-1976 . . 6 3 Map of study area 9 4 Cross-section X-X' of study area 11 5 Construction of well DH #137 12 6 Construction of piezometer DH #138 14 7 Construction of piezometer DH #118 15 8 Construction of well DH #117 16 9 Construction of well DH #97 17 10 Response to slug injection on well DH #116 20 11 Drawdown test on well DH #118 - PW DH #117 22 12 Recovery test on well DH #117 23 13 Piezometric surface of overburden aquifer in October, 1978 27 14 Piezometric surface of coal aquifer in October, 1978 . . 28 15 Water table fluctuation recordings 30 16 Approximate extent of mining 37 17 Estimated Pit Inflow 41 18 Piezometric surface profiles at 100 days and 3000 days after pit is opened 44 A-1 Construction of piezometer DH #60 50 A-2 Construction of well DH #61 51 A-3 Construction of piezometer DH #62 52 A-4 Construction of well DH #96 53 A-5 Construction of well DH #116 54 A-6 Construction of piezometer DH #119 55 iii LIST OF FIGURES (Cont'd) Figure Page A-7 Construction of well OH #122 - Ennis Draw 56 A-8 Construction of well DH #132 57 A-9 Construction of well DH #133 58 A-10 Construction of piezometer DH #134 59 A-11 Construction of well OH #162 60 A-12 Construction of well OH #163 61 A-13 Construction of well DH #171 62 A-14 Construction of well OH #172 63 A-15 Construction of piezometer DH #173 64 A-16 Construction of piezometer OH #174 65 B-1 Specific capacity test - Well #172 71 8-2 Recovery test - Well #172 72 B-3 Slug test - Well #122 73 8-4 Specific capacity test - Well #117 74 B-5 Recovery test - Well #117 75 B-6 Drawdown test - Well #118 - PW #117 75 B-7 Drawdown test - Well #119 - PW #117 77 B-8 Specific capacity test - Well #137 78 B-9 Recovery test - Well #137 79 B-10 Slug test - Well #116 80 B-11 Specific capacity test - Well #61 81 B-12 Recovery test - Well #61 82 B-13 Drawdown test - Well #62 - PW #61 83 B-14 Drawdown test - Well #60 - PW #61 84 _ D-1 Approximate location of existing wells (Map) 100 iv LIST OF TABLES Table Page 1 Summary of Hydraulic Properties of Aquifers 18 2 Summary of Water Surface Elevations, October 9, 1978 . 26 3 Quality of Coal and Overburden Waters 32 4 Well Inventory 34 5 Distance From Pit to Line of Zero Drawdown in the Laramie Formation 43 6 EC and pH of Saturated Extracts 46 C-1 Specific Capacity/Recovery - Well #61 85 C-2 Drawdown/Recovery - Well #61 - OW #60 87 C-3 Drawdown/Recovery - Well #61 - OW #62 88 C-4 Specific Capacity/Recovery - Well #117 89 C-5 Drawdown - Well #117 - OW #118 91 C-6 Drawdown - Well #117 - OW #119 92 C-7 Slug - Well #116 93 C-8 Slug - Well #122 (Ennis Draw GWOW) 94 C-9 Specific Capacity/Recovery - Well #137 95 C-10 Specific Capacity/Recovery - Well #172 97 v Conclusions and Recommendations Existing water resources within the leasehold and immediate vicinity that will be affected by mining are subsurface waters contained in the target coal seam, the Laramie formation overburden, and the blow sand and stream deposits associated with a broad flat depression known as Ennis Draw. The Larimie-Foxhills formation, the most important aquifer in the area, is more than 200 ft below the coal seam proposed to be mined. No effects of mining on the Laramie-Foxhills aquifer are anticipated. Surface runoff in the area is essentially non-existent under present conditions. This is not expected to change provided that three or more feet of the existing blow sand are placed over the spoil in the reclam- ation phase. The target coal seam and the Laramie overburden are hydraulically independent aquifers. The coal seam is a confined aquifer but waters in the overburden are only locally confined. Flow of ground water through the coal seam is negligible as the transmissivity of this aquifer is extremely small . Groundwater flow in the overburden is toward the north- east. Approximately 5.4 acre-ft of groundwater per year are discharged from the leasehold area. This flow apparently enters the blow sand and stream deposits associated with Ennis Draw. The source of this flow is external to the study area and enters the project area by lateral flow. Recharge of the overburden aquifer in the study area is believed to be essentially zero. The water in the overburden aquifer is of poor quality, the dissolved solids concentration exceeding 7000 mg/1 with a sodium-adsorption-ratio greater than 10. Probably the only viable use of the water in the over- burden is for dust control or similar purpose. Waters contained in the 2 blow sand and stream deposits associated with Ennis Draw exhibit a much better quality, the dissolved solids concentration ranging between 750 and 1000 mg/l . There is, apparently, subsurface flow from the south in Ennis Draw which is sufficient to• dilute the small quantities of saline inflow from the Laramie. The quantities of pit inflow were estimated using a succession-of- steady-states computation procedure, together with the mining plan and the hydraulic properties of the aquifer as determined by aquifer tests on the proposed mining site. The peak inflow rate is estimated to be some 130 gpm and will occur when pit B has reached its maximum length of 3000 ft. The inflow from both pits A and B are included in this estimate. The estimated peak inflow is believed to represent a maximum that can reasonably be expected to occur. Several aspects of the com- putation tend to cause the estimates to error on the high side. The quality of the inflow should not be substantially different from the quality of existing overburden waters. The distance from the pit to points where the piezometric surface in the overburden will remain undis- turbed is approximately 0.5 miles. Therefore, at any time, drawdown of the piezometric surface in the overburden is not expected to extend more than about 0.5 miles beyond the boundaries of the area to be mined. Unless specifically avoided, the pit will apparently intersect and cut through the stream deposits and blow sand associated with Ennis Draw in one limited area. Inflow to the pit from these deposits may equal or exceed the inflow from the Laramie. Drawdown of the piezometric surface in these deposits caused by mine inflow can be expected to be substantial . It is recommended that special care be taken to protect the integrity of the ground waters in the blow sand and stream deposits associated with 3 Ennis Draw. Adverse effects on these waters should be minimized by restricting mining operations so that the stream deposits in the old Ennis Draw are not intersected or by protecting them by a compacted shale trench. It is believed that mining will have no appreciable effect on the hydrologic budget of the area, and that water levels in the mined area and in the Ennis Draw deposits will recover to approximately their original levels following the end of mining. Provided that care is taken to min- imize hydraulic communication between the Ennis Draw deposits and the mined area, there should be no significant long term adverse effects of mining on the quality, quantity, or distribution of water resources in the study area. 4 I. Introduction The Department of Agricultural and Chemical Engineering, Colorado State University, agreed by contract with the Adolph Coors Company of Golden, Colorado to make a preliminary study of the water resources in the vicinity of a possible coal strip mine site located in sections 25, 26, .35 and 36 (approximately) , T3N, R64W, Weld County, Colorado. The objective of this study was to evaluate the water resources at the potential strip coal mine site relative to the following concerns: a. Quantity of existing water resources, b. Quality of existing water resources, c. Potential impacts of mining on quantity of water, d. Potential impacts of mining on quality of water, e. Quantity and quality of mine inflow. To achieve this objective 21 wells were drilled in the study area to provide a means for identifying aquifers, measuring piezometric sur- face elevations, measuring the transmissivity and storage coefficients and collecting water samples from each aquifer. The report contains a summary of the data collection procedures, analyses of the data and the conclusions derived in the course of this investigation. II. General Description of Hydrology and Geology A. Climate The climate of the study area is characterized by low relative humidity, cold winters and modestly hot summers. The mean annual temper- ature as recorded at Greeley and Fort Lupton is about 48°F. From 1952 to 1976 the average annual precipitation ranged from 12.08 inches at Fort Lupton to 12.28 inches at Greeley. The maximum monthly precipitation normally occurs during May; the minimum normally occurs during January 5 in the form of a light, dry snow. About 52 percent of the annual pre- cipitation falls during April , May, June and July and only about 13 per- cent is received during November, December, January and February. The mean monthly precipitation during the period of record for both stations is shown graphically in Figures 1 and 2. B. Geology Rocks of the Precambrian to early Cretaceous age underlie most of the area at great depths. These deposits are overlain by the Pierre shale and generally dip westward. The Pierre shale consists of a thick sequence of fossiliferous marine shale, silt, and clayey sandstone, which contains numerous calcareous concretions. The upper part of the formation is transitional with the overlying Foxhills sandstone. 'The Foxhills sandstone is yellowish-brown calcareous marine sand- stone interbedded with dark-gray to black sandy shale and some massive white sandstone. The zone of contact with the underlying Pierre shale consists of gray sandy shale and shaly sand. The overlying non-marine Laramie formation is also transitional , and contains some lignite and other non-marine beds which occur in the upper part of the Foxhills. The Laramie formation consists mainly of yellow-brown and gray to blue gray soft carbonaceous shale and clay interbedded with sand and shaley sand.. It contains some crossbedded gray to buff sandstone, which is slightly to well cemented, and coal , especially in the lower part. The Laramie formation forms the bedrock across much of western Weld County. Much of the bedrock is covered by unconsolidated Tertiary and Quaternary deposits. The unconsolidated deposits consist of dune sand, — 6 3.O— I a) - c 2.O' c 0 o l I 1.0- a) a, F I , Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Figure 1 . Mean monthly precipitation at Greeley, 1952-1976. 3.O- N d L 0 2.O- C o L` I.O a) Q_ O' 1 _ Jon Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Figure 2. Mean monthly precipitation at Fort Lupton, 1952-1976. 7 alluvium and terrace deposits. These deposits are generally flatlying or dip gently eastward. Only the formations of Late Cretaceous and younger are of interest in this report. In particular the sand overlying the Laramie formation, — stream deposits near the east boundary of the site, the Laramie above the .coal and the coal itself are of interest. These formations are exposed or underlie the project area at relatively shallow depths. Since the Laramie-Foxhills aquifer is confined and exists more than 200 ft below the coal seam to be mined, it is expected that it will not be affected by the mining of coal in the overlying Laramie and was , therefore, not of major concern in this study. C. Water Resources Most of the residents in the vicinity of the study area depend on privately owned wells for domestic and livestock purposes. Data collected on 24 wells indicate that 7 of these wells, located in the close proximity of the leasehold, penetrate the stream deposits overlying the Laramie in a broad depression known as Ennis Draw. The remaining 17 wells are apparently completed in the sandstone beds of the Laramie-Foxhills. These wells are generally 4 to 6 inches in diameter. Most of the domestic wells are equipped with a submersible pump driven by an electric motor. Wind- mills power many of the stockwells. The average yield of these wells is about 2 gpm. There is no evidence of surface runoff in the vicinity of the site. Essentially all precipitation apparently infiltrates the highly permeable mantle of sand. No water-formed erosional features are evident, not even small rills or gullys. Ennis Draw is a broad, flat-bottomed depression with no observable channel or gully and shows no evidence 8 of the existence of surface flows. The thickness of the blow sand overlying the Laramie is variable but is sufficient to hold a large quantity of capillary water. This observa- tion, coupled with the small annual precipitation relative to the poten- tial evapotranspiration, makes it unlikely that significant recharge to the Laramie through the sand exists. This sand is not known to yield water to wells except in conjunction with the stream deposits in Ennis Draw. Ground water exists in the coal seam of interest and in the over- burden. The saturated thickness of the overburden is some 65 ft. Lateral movement of this water is toward the northeast in the study area and undoubtedly discharges into the sands and stream deposits in Ennis Draw to the north and east of the project site. Ground water in neither the coal _nor overburden is known to provide a water supply for any purpose in the study area. III. Pre-Mining Subsurface Hydrology and Water Quality in Detailed Study Site A. Geology A map of the study area is shown in Figure 3. The study site covers about six square miles and includes Sections 25, 26, 35, and 36. The land is gently sloping to the northeast toward Ennis Draw which is located on the eastern boundary of the study area and generally runs in a north- south direction. A preliminary look at geophysical logs suggested that it would be impractical to identify individual aquifers in the overburden sequence. It was, therefore, decided to treat the coal , overburden and the over- lying sand as individual potential aquifers. An east-west cross-section 9 ---\--� G�0--.� 1 yii o �.�.a ,o %e}C'.: I Q \•.\•.\----•5n ,:',•49'\ 1O) � 72,� " _•1 23 O , \24 0(ei / ti 19 D cr2 � iii \ \ CD 6E .;744)I2:),;>\\ ) �2 ga \ \ cA's! \ \ (. , \ 1\ 8 C,' 18) CJ 6z 50 =' O �� 132°�5 ,a0041 it°w ta„ \)\--,' ,0 G e �" ��ro \\133 �41i o ��1 I `t `, aw -a..ffM` I 5 J ieli _ 0 36 '' Li 360 \ "--7,\ .am ti/ e �d ��p o U4941:-:1;;;;,, 9�� 0 a \ � V v � �� g / rf o\° GROUND WATER STUDY o PT" v' T2 N_„2 PROPOSED SURFACE COAL MINE .o // -`�� `` ADOLPH COORS COMPANY, GOLDEN, COLORADO ` I i \ J` J i O GROUND WATER OBSERVATION WELL IN COAL SEAM -�A ' n 7 'es ,q 0 PUMP TEST IN COAL SEAM wo � I n„c'\vio ° \` 0 GROUND WATER OBSERVATION WELL IN OVERBURDEN \` L'v D G ', �f PUMP TEST IN OVERBURDEN .' -: / O �\ • PIEZOMETER FOR AQUIFER TEST '�� 1°. ti12?' G 0 O EXISTING WELL I yo,i� winding '�z riP _/3 WELL NUMBER V '! 7�.'0 \ o�° a o -� C SCALE: feet %,-\\, I, 'c.Ii �D�'-�� \i C 0 2x00O 40W 6000 V ., -�, l., ?, Figure 3. Map of study area. 10 showing the various strata is provided in Figure 4. It can be observed that the sand deposit is essentially of uniform thickness. On the average, the deposit is feet thick and dips gently eastward. The overburden is composed mainly of sand, clay, shaly sand and crossbedded sandstone. The thickness of this deposit decreases in an easterly direction from 146 feet at the western boundary of the study area and practically vanishes at Ennis Draw. In Ennis Draw the overburden material has been replaced by stream sediment as shown in Figure 4. The maximum thickness of the coal seam is approximately 8 feet and occurs toward the center of the project area, but subsequently thins to about 2 feet at the north and east boundaries. The depth to the coal seam from the ground surfaca varies between 170 feet at the western boundary of the site to approximately 70 feet at Ennis Draw as shown in Figure 4. -Although the overlying sand deposit is highly permeable it does not contain water and, therefore, cannot be considered an aquifer. Both the coal and the overburden are water bearing formations and are, there- fore, the only aquifers considered in this study. B. Characterization of Hydraulic Properties of Aquifers Twenty-one wells have been constructed for the purposes of the hydrologic study. The locations of these wells are shown in Figure 3. The drilling and testing program was designed to treat the coal and the overburden as individual potential aquifers . A total of 10 wells were constructed to provide hydrologic data on the coal seam. Wells numbered 61 , 116, 132, 137, 162 and 171 are all 5-inch diameter wells completed in the coal . Figure 5 shows the typical construction details for these wells. Four additional wells numbered 60, 62, 134 and 138 are 2-inch diameter wells constructed for the purpose 11 8 b R m P O m P O O T 0 I O - L I I \yy,7 E cI �_ . ° EI S N a y1 AI K ml . i. n !• f N { • NI 1 m It.._ M Ol m lt':, u_ _ t a, m I i CU 'r al Iaa m !L_ >, II c -o .1. } J u o l i— L t N V 4F m I m O � 1 II I Z.Z. , it liTC in X iII— f; E I 4-1 I e U - --1 tI la i m H U N _\ 8 V -Fr-t---, F ---`t V N cr ta co c cirri N Ev I I c fF. ca ITI ° Ts al � v� i 1 = II N O 0 0 0 0 0 0 O to N co ? 0 to m m CO n m e a -t o V V. Q 12 216" Ground Surface 1 IO Cement a: • BLOW SAND .4 o. L 7=c ` 7%e Q Borehole .. ' .: '. n a� ev,'•� 5 ID. Casing 1 OC . 121' o'c 3:. Grovel LARAMIE p _ FORMATION 143' c �o es Cement Seal 7Packer I"44' COAL SEAM 8 _ Slotted Cooing r 4' - J SHALE Figure 5. Construction of well DH #137. 13 of observing drawdown during pumping tests. The typical construction of these wells is shown in Figure 6. Wells with 5-inch diameter completed in the overburden are numbered 96, 117, 122, 133, 163 and 172. Wells numbered 118, 119, 173 and 174 are 2-inch diameter wells completed in the overburden as drawdown observation wells. Typical well construction of the 5-inch and 2-inch wells completed in the overburden is shown in Figures 7 and 8. Well number 97 is completed in both the overburden and the coal as shown in Figure 9. Schematic drawings of the remaining wells are contained in Appendix A. Seven separate determinations of the transmissivity of the overburden were made. The wells involved in these determinations were 172, 122, 117, 118 and 119. Two determinations of the storage coefficient were made by measuring the drawdown in wells 118 and 119 in response to pumping from well 117. Similarly, eight determinations of the transmissivity of the coal seam were made by running various tests on wells 137, 116, 61 , 62, and 60. Two values of the storage coefficient in the coal seam were estimated from drawdown data in wells 60 and 62 in response to pumping from well 61 . The results of these tests are summarized in Table 1 . Details of the computations are presented in Appendix B and the raw data in Appendix C. 14 2 I „o 8 Ground Surface 1 ► • Id Cement O BLOW SAND :o , 6-..... -i:.oO 5.:.C Oc J.:.. 3 11 ;.,c a_ 4 4) Borehole 00 0. it; 2" Schedule 40 PVC ft > . Casing 122 >o ,, Gravel 144. o o' o J, LARAMIE FORMATION .4:49 .9 a b9 5 Cement Sea! 7. Packer - = Slotted Casing B, _ COAL SEAM r 1 SHALE Figure 6. Construction of piezometer DH #138. 15 Ground Surface Ip' Cement a o 2" Schedule 40 PVC o C jc o. Casing AC Gravel BLOW SAND 42 � Cement Seal —Packer 4% Borehole 142' - _ _:`—Slotted Casing 90 _ 60 = LARAMIE FORMATION L = IO Top of Coal Seam Figure 7. Construction of piezometer DH #118. 16 13 Ground Surface 10 Cement :0. 5u I. D. Casing o. 53 ctr BLOW SAND 11) 30 ' Gravel Cement Seal 1 ,--Packer 142 - - — 7 %8 Borehole !I!I! Slotted Casing 40 - - LARAMIE FORMATICN • 10 Top of Coal Seam Figure 8. Construction of well DH #117. 17 (7" i Ground Surface 1 \ r • I? Cement 1- , Jc s"' : iT Gravel BLOW SAND 33 .o• a UI 5" I.D. Casing Packer STREAM SEDIMENT 82' - —7%8 Borehole 49 = _—' Slotted Casing LARAMIE. FORMATION _ = COAL. SEAM _ Figure, 9. Construction of well DH #97. 18 Table 1 . Summary of Hydraulic Properties of Aquifers Aquifer Well No. Type of Test Transmissivity Storage ft2/min Coefficient Overburden 172 Specific Cap. 3.2x10-3 - Recovery 1 .1x10-2 - 122 Slug 9.3x10-3 - 117 Specific Cap. 2.7x10-3 - Recovery 1 .8x10-3 - 118 Drawdown 2.0x10-2 7.6x10-4 119 Drawdown 3. 1x10-3 8.7x10-5 Coal 137 Specific Cap. 1 .0x10-3 - Recovery 9. 7x10-4 - 116 Slug 1 .7x10-4 - 61 Specific Cap. 2.6x10-4 - Recovery 7.3x10-4 - 62 Drawdown 2.2x10-2 7.2x10-4 60 Drawdown 1 .8x10-2 5.4x10-4 19 Tests performed for the determination of the above aquifer character- istics include the following. Results from the recovery test are probably the most reliable. a. Slug Test - This involved submerging a closed cylinder of known volume into the well over a time period sufficiently short to be considered an instantaneous injection. Before initiating the test the static level in the well was recorded. The residual buildup of piezo- metric head was then observed in the injection well itself at selected intervals of time until the test was completed. b. Drawdown Test - Immediately before starting the pump, the water levels in the observation wells and in the pumped well were measured to determine the static water levels upon which all drawdowns were based. The instant of starting the pump was recorded as the zero time of the test. If the initial discharge was in excess of the continuous discharge, the valve in the discharge pipe was then adjusted so as to maintain the discharge as constant as possible throughout the test period. Water levels in the observation wells and pumping well were measured at selected intervals of time until completion of the test. c. Recovery Test - When the pump was stopped after running the drawdown test, the drawdown and time at which it was shut down were recorded. Measurement of water level was immediately initiated in the pumped well and in the observation wells where appropriate. The sane procedure and time pattern was followed as at the beginning of the draw- down test. As in the drawdown test, the time and water level are recorded for each measurement. For the slug test analysis, the residual buildup in well 116 was plotted on coordinate paper against the corresponding values of lit as shown in Figure 10. Note the line must pass through the origin , a point 20 In I N O m 0 .: _ N O O c II E > N a O _ N E n = 'I — O 0 > F N 3 c C _ C - o U a) 0 _ — C N O Cr) o N C O a--) 0 '.- 0 v a 0 a N _ O O 0 O S- • Q' u- 0� 1ro M (V lea; ` s- 21 that corresponds to infinite time after the injection. Selecting arbi- trarily the point on the line with coordinates -s = 3.0 feet and lit = 0.013 min-1 , the transmissivity was calculated as: T = V (0.52) (0.013) = 1 .7 x 10-4 ft2/min 47t(-s) 47(3) Drawdown test data were analyzed using the Jacob Method. Data from observation well 118 were used to illustrate the procedure. The measured drawdown was plotted on the coordinate axis of semi-log paper vs time on the log axis as shown in Figure 11 . The straight-line portion of the plot is projected to intercept one or more log cycles and the zero draw- down axis. The values of transmissivity and storage coefficient were computed as follows: T = 2.303Q = (2.303)(0.146) = 2 x 10-2 ft2/min 4746 47(1 .3) and S = 2.246Tto = (2.246) (2x10-2)(42) = 7.6 -x 10-4 r2 (50)2 where: os = drawdown over one log cycle, to = time at zero drawdown intercept, and r = distance from pump well to observation well . Data from well 117 are used to illustrate the procedure for analysis of recovery data. The measured drawdown was plotted on the coordinate scale of semi-logarithmic paper and the corresponding value of t/(t-tp) on the log scale as shown in Figure 12, where tp is the duration of the pumping period. The slope of the line is 15.15 feet per log cycle which yields a transmissivity of: T - 2.303Q = (2.303) (0.146) = 1 .77 x 10-3 ft2/min _ 47As 47(15. 15) 22 8 I I e- - -o 8 -o -o N V G Ea O a S m 0 0 0 >< I O N x C9 CO V N h to p n a> N II II II II R o a E a) - 3 — a> E o I- J N CU Y 3 3 O S- —O• O p i — (1) � � M O N — O O O O O O O yaa) I $ umOpMOIQ 23 O I I _ o 0 -o c M m O In - O _ V - x O O to ^ _ p _ I' N II d a I- - n ' 3 N _ p v _p i O V N r N N S- 01 I I 1 p C.) O p O O O M 083' 5- UMOpMDJQ 24 Pump discharge during the tests were all on the order of 1 gpm. The source of a portion of the pump discharge was the water standing in the well bore. Thus, the pumping rate from the aquifer itself was substan- tially less than the pump discharge. The equations used for analysis of the data do not account for this discrepancy. The effect is to cause the transmissivities derived by this procedure to be greater than actually exist. Therefore, the transmissivities reported in Table 1 should be regarded as upper limits, the actual values being somewhat smaller. In any case, the values shown in Table 1 are very small , indicating very poor aquifers. In fact, neither of the zones tested would be regarded as aquifers at all in most contexts. The values of storage coefficient reported in Table 1 suggest that both the coal and overburden are confined aquifers. We are fairly con- fident that the coal seam is, indeed, a confined aquifer with little or no communication with the overlying waters. Evidence to this effect is provided by the fact that the piezometric surface for the coal seam, throughout the project area, is lower than the piezometric surface for the overburden. This observation is depicted in the cross-section in Figure 4. Pump test data in the overburden provide an estimate of storage coefficient on the order of 10-4 in the vicinity of wells 117, 118 and 119. This value certainly suggests that the overburden aquifer is con- fined at this location. Furthermore, the static water levels in wells 117, 118 and 119 stood well above the interface between the Laramie and the overlying blow sand. This observation supports the conclusion that the overburden waters are confined in the vicinity of these wells. Comparison of static water levels in the remaining overburden wells with 25 the elevation of the top of the Laramie are presented in the cross-section in Figure 4. It can be observed that the water table profile lies beneath the top of the Laramie. This suggests that the overburden aquifer is uncon- fined over the rest of the project area. C. Piezometric Surface Water surface elevations in 23 wells were measured relative to a common datum. The data obtained is summarized in Table 2. Contour maps of the piezometric surface were prepared for the overburden and coal aquifers and are presented in Figures 13 and 14 respectively. The piezometric surface in the overburden is relatively featureless and slopes toward the northeast at a gradient of about 0.006 as shown in Figure 13, indicating that the ground water in the project area dis- charges into the subsurface deposits in Ennis Draw. The discharge rate, Q, through the boundaries of the leasehold was computed on the basis of Darcy' s Law which can be expressed as: Q = TIL where T is the transmissivity, I the hydraulic gradient and L the width of flow. Using an average transmissivity of 7 x 10-3 ft2/min, a hydraulic gradient of . 006 and an average flow width of 6000 feet, the discharge rate through the eastern boundary of the study area was estimated to be approximately 3 acre feet per year. In a similar manner the discharge through the northern boundary was computed to be about 2.4 acre feet per year. This gives a total discharge from the project area to Ennis Draw of approximately 5.4 acre feet per year. The piezometric surface map in the coal depicts a ground water divide — along wells 134 and 116 as shown in Figure 14. East of the divide the 26 Table 2. Sumary of Water Surface Elevations October 9, 1973 Aquifer Well No. Reference Depth to Water Surface Point Elev (ft) Water (ft) Elevation (ft) Overburden DH 174 4811 .22 33.55 4777.67 - DH 173 4810.81 34.15 4776.66 DH 172 4811 .02 37.50 4773.52 DH 163 4847.59 52.29 4795.30 DH 133 4880.20 74.84 4805.36 ' DH 122 4814.23 15.97 4798.26 DH 119 4831 .72 22. 14 4809.58 DH 118 4828.10 25.64 4802.46 DH 117 4829.90 21 .78 4808.12 DH 97 4790.10 11 .53 4778.57 DH 96 4763.80 7.40 4756.40 W 22 4823.00 11 .46 4811 .54 W 21 4793.00 13.70 4779.30 Coal DH 171 4811 .35 34.95 4776.40 DH 162 4847.59 53.42 4794.17 DH 138 4876.80 82.44 4794.36 DH 137 4876.46 81 .78 4794.68 DH 134 4874.80 80.54 4794.26 DH 132 4879.64 100.48 4779.16 DH 116 4832.00 49.76 4782.24 DH 62 4819.90 40.50 4779.40 DH 61 4820.00 41 .56 - 4778.44 DH 60 4819.80 40.34 4779.46 27 23 24 19 3 3 ? M CD CO z e: DH96 oD 173 2• oDH 16 26 25 0760-0 30 t. DH133 0W21 35 36 DH1180 4780 0 H122o T3N T2N 4800.0 2 1 / 6 / W 22 : 0 c Elevation in feet above mean sea level Figure 13. Piezometric surface of overburden aquifer in October, 1978. 28 23 24 19 O 0 O O v a rn II) O lb 0 co `o a) a) w co cc cc 1` N. N- N. . R V . \ DH162 oDHl71 '.a....\\26 25 t 30 'oDHl34 oDH 60 1l o\ `. = DH132 / 35 36 31 DHIl6o / / / . T3N / T2N / . 2 I l 6 '. Elevalian in feet above mean sea level Figure 14. Piezometric surface of coal aquifer in October, 1978. 29 piezometric surface slopes toward the northeast at a gradient of about .004. Ground water discharge from the coal seam toward Ennis Draw was estimated to be about 0.1 acre foot per year. This discharge is very small and coal aquifer discharge was not considered further in our analysis. Continuous water level recorders have been installed on wells 61 , 122 and 117 to record water level fluctuations in an attempt to estimate the quantity of recharge. The water level fluctuations recorded to date are presented in Figure 15. Since the generated data comprises a very short period of time (approximately 2 months) , it is not possible to draw any definite conclusion concerning recharge. However, the fluctu- ations do provide further evidence concerning the confined or unconfined nature of the overburden waters. Water levels in wells penetrating confined aquifers can be expected to respond to changes in atmospheric pressure, while the water level in wells penetrating unconfined aquifers are generally insensitive to changes in atmospheric pressure. The water levels in wells 61 (coal ) and 117 (overburden) exhibit fluctuations typical of confined aquifers responding to changes in atmospheric pressure. Note that the fluctuations in these two wells correlate very nicely, indicating that the cause of the fluc- tuations are the same in both cases. In contrast, the water level in well 122 shows almost no fluctuation during the same time period. These observations strongly indicate that the overburden aquifer is confined in the vicinity of well 117 and unconfined in the vicinity of well 122. D. Water Quality Samples for the determination of water quality were collected at two locations in the overburden (wells 117 and 172) , two locations in the coal (well 61 and 137) and three locations in Ennis Draw (wells 96, 30 • - -,..., -,- - _. a -� - -M - - _Cl c, N 0) C — Co O —'N O N U T a o i I C - _ _ v al O N c H 4-1 CU O ca i _ N 4-J - - - - v 3 in N - - r, - m N N O i rn 2 0 CI - 0 Ls- - CD • • • 0 a o o 0 o o c o 0 0 in 0 r` CO rn 0 N LC; tp 0 O O .- — r- N C V O N N N N N ;aa; - aa;epi 0; y;Gad 31 97 and 122) . The results of the analysis on the seven samples are shown in Table 3. The samples from Ennis Draw, on which the analysis were made, were collected after continuously bailing the wells. Those from the coal and overburden were collected from the pump discharge at the end of the pumping period during the aquifer tests. During the pumping period, the electrical conductivity, temperature, and pH were measured in the field at the time of sample collection. The samples collected were filtered through a 0.45 micron filter and one-half of the sample was acidified. The samples were then transported to the laboratory. The data in Table 3 show a striking difference between the waters in the coal and overburden. The water in the coal is of significantly better quality than that in the overburden, although in neither case can the water be regarded as acceptable for many uses. The large difference between the water quality in the coal and overburden aquifers is further evidence of little or no hydraulic communication between the coal and the overburden. Trace elements concentrations are generally low, the exception being iron in sample 117 and boron in sample 172. The observation that the trace elements in the overburden waters are significantly more concentrated than in the coal waters is probably partially explained by the fact that the overburden waters exhibit a lower pH than the coal waters. The sodium adsorption ratios (SAR) range from 10 to 18. These rather high SAR values, coupled with the high dissolved solid content, cause the waters to be classified barely acceptable to unacceptable for irrigation, although this depends upon the type of soil and crop to which they would be applied. 32 * « . r 0000000 v) ---... M O O M O r CV O Cr1 LO N. CV cn in CTI 0 H E r r r` in n M N O U 0 0 0 0 0 0 0 CD OM 00 CD r r- v Y N r r CO r c t 0 0 0 0 CO 0 _ O N l0 O 00 M O r N M a' 00 CI CV r- VI r0 m N O S. = t•-• 0 1`.. l0 01 O C •• r (0 V l0 r Cc 3 Cr) Cr) LO M 01010) i Lf) 01 Lf) N. LC) N. CO 01 C F Nct M OMN .0 U V V r V N N r r •O Ln Ln Ln Ln Lo Ln LL) i U VVVVVVV O CO Gt CO O Cr) CO 1.0 a ro • C) U r MLA •V • • • • SC7 uD 10 r CJ LO LV) CO Ln C7 d' Q) \ N r ._ r v v N v r c> V V O a) • -0 on E N 0 0 0 0 0 0 r 0 0 0 0 0 0 0 C.J C 0 .D \ Ln Ln Ln Lc) En Ln r- W r0 Z 0 0 0 0 0 0 0 d v V v v v v w r0 0 M N LC) r VD CO L n CT N N N CO O S. O C • • • a V 01 t et r- Cr) 0 U 0 L n LCI CSIMCV et LC) N4 r rl0 N N r r N. r v N. r0 0 O Cr) O N ID d• CO N V U ^ LV LV NLV rN E >, 0 +•, U Mtne ^ LO MCT O •p_ = N I- M O O Ln r $.. reOra110 LC) 4- '0 O) N N M O Cr") r Cr) CO O co 0 U- •• O C N N U (Orr Cflr CVtn Y r r r0 • O) r (O N- r\ N N. N E _ M • 10 C11O1rN MN EL) a0 rrrr ++ - -N • 00 000 LOON LO E Z in %-...LC) C0O Ct C) CD COLE) t0 S 2 TSS 22 Lal . ... . .. . (1) 0000000 .) r 0 0O r N r r I— 0t C.; g = M L n L n l0 L n e t (O CI. • ) 1� 1— tO I- CO tO 0 Lv r l0 1 r- N r- N (O CI Ol r N co r` O r r r r E Z Ln 0000000 33 The data in Table 3 also indicate that the water in Ennis Draw is of significantly better quality than that in the overburden and coal . In fact, the dissolved solid concentration of the overburden waters is greater than that of Ennis Draw by a factor of 6. In addition to determining the quality of ground waters in the leasehold, samples were collected from twenty-four additional wells in the general vicinity. The location and number of these wells are shown on the map in Appendix D. The temperature and electrical conductivity of the sampi �s were measured. These data, together with other information supplied by the well owners, are presented in Table 4. It is difficult to draw any firm conclusions from the data on the wells in Table 4 because of insufficient knowledge of the depths, aquifers open to the well bore, and water levels. However, wells numbered W-1 , W-2, W-3, W-5, W-6, W-10 and W-24 which are all in the vicinity of the leasehold, are apparently completed in aquifers below the coal seam elevation. This is judged on the basis of the static water levels, length of pipe, and depth of hole. The total dissolved solids concen- tration (estimated from EC) is on the order of 750-1000 mg/1 in these wells. Information gathered from the city of Keensberg indicate that the dissolved solids concentration of the Foxhills waters is approx-mately 700 mg/l . This would strongly suggest that the above mentioned wells are completed in the Foxhills sandstone. Wells W-4, W-7, W-8, W-9, W-21 , W-22 and W-23 are relatively shallow wells located in Ennis Draw. Judging from their depths , static water levels and/or dissolved solids concentration, we firmly believe that these wells withdraw water from the stream sediments in the draw. However, it is possible that wells W-4 and W-9 are being affected by waters in the 34 Table 4. Well Inventory Windmill Owner Static Total Depth Length Temp Spec.Res. EC EC No. (Ranch) Level of Hole of Pipe °C ohm-cm @ T @25°C (ft) (ft) (ft) mmhos/cm W-1 2-E 111 420 222 17 750 1 .33 1 .581 W-2 2-E 190 372 252 17 870 1 .15 1 .367 W-3 2-E 100 400 147 17 950 1 .05 1 .248 W-4 L-F 50 - - 14 600 1 .67 2.133 W-5 2-E 210 - 242 17 940 1 .06 1 .260 W-6 . 2-E 170 390 178 18 1000 1 .00 1 .163 W-7 L-F - - - 17 1010 0.99 1 .177 W-8 L-F 10.55 150 - 17 860 1 . 16 1 .379 W-9 L-F 9. 10 150 - 18 500 2.00 2.326 W-10 L-F - - - 14 2250 0.44 0.562 W-11 L-F 165 580 - 16 340 2.94 3.581 W-12 L-F 173 402 - 17 430 2.33 2.770 W-13 2-E - - - 17 1200 0.83 0.987 W-14 2-E - - - 18 900 1 .11 1 .291 W-15 L-F 4. 0 100 - 15 1100 0.91 1 .135 W-16 L-F 95 300 - 17 1500 0.67 0.797 W-17 L-F - - - 15 2900 0.34 0.424 W-18 L-F - - - 16 3400 0.29 0.362 W-19 L-F - - - 15 3500 0.29 0.362 W-20 L-F - - - 15 3100 0.32 0.399 W-21 RC 13.70 21 - 3 1225 0.82 1 .400 W-22 — RC 11 .46 22. 5 - - - - - W-23 RC 9.78 21 - 3 - 460 2. 17 3.710 W-24 RC 150 465 - - - - - 35 coal and overburden aquifers, E. Summary of Existing Situation Based on our analysis we have concluded that the overburden waters in the project site are unconfined except in the vicinity of well 117 where the overburden aquifer is locally confined. We are fairly confident that the coal seam is indeed a confined aquifer. The fact that the piezometric head in the overburden is greater than in the coal suggest that there would be a tendency for water to move from the overburden into the coal if sufficient permeability existed. Evidence that such is not the case is provided by a comparison of the water quality in the two zones. The dissolved solids concentration in the overburden water is greater than in the coal waters by a factor of 2 or more. If there were significant hydraulic communication between the two aquifers the dissolved solids content of the two waters should not show such a dis- parity. Groundwater discharge through the coal seam was about 0.1 acre foot per year. This discharge is so small that it can be neglected for all practical purposes. Flow from the overburden to Ennis Draw was estima -ad at approximately 5.4 acre feet per year. It is not possible to calculate the actual flow from the south through Ennis Draw based upon data presently available to us. However, we do believe that the discharge through the draw from the south is significantly greater than the lateral inflow contributions from the over- burden in the study area. Evidence that such is the case is provided by a comparison of the water quality in the overburden and Ennis Draw. The fact that the overburden waters, with a dissolved solids concentration of 7025 ppm, discharge into the draw suggests that the much lower dissolved 36 solids concentration observed in Ennis Draw must result from dilution with better quality water flowing from the south through the sand and stream deposits in the draw. Locally, water may be trapped in Ennis Draw. Although the water in the coal is of significantly better quality than that of the overburden, in neither case can the waters be regarded as acceptable for many uses. Anticipated changes in water quality as a result of mining are discussed in a subsequent section of this report. IV. Subsurface Hydrology and Water Quality During Mining A. Pit Inflow Estimates Extraction of the coal seam by removing the overburden in strips and backfilling in the adjacent pit will completely disrupt the natural sequence of strata from the bottom of the coal seam to the surface. The existing strata will be replaced by a mixture of geologic materials in the form of rubble produced by the blasting and excavation of the over- burden and coal . The area to be mined is divided into three subareas , designated pits A, B, and C as shown in Figure 16. Except for a small area in the north- west corner of Pit A, the overburden will be removed by drag line, exposing the coal in a pit with the geometry of a trench 100 ft wide and 3000 ft long on the average. Operations will begin on the north boundary of Pit A and progress southward; the long axis of the pit being oriented in an approximate east-west direction. Mining will be confined to Pit A for the first year while a buried pipeline is removed from Pit B. After removal of the pipeline, the drag line will alternate between Pits A and B on each pass. Coal removal will occur in Pit B while the drag line is in Pit A and vice versa, — \ 37 \i_ Jr 71° t>"; ) ri-tt • \ 231 O\• 'o \\ 2aoD l \� IV 0, if J� J CA WS �1 '� ) i %I N \ \ \�% \ �� ` t2 "-I62 v'> 172„'s .' \-' 2t,N,_\.4P/r 6 \ /7- '5,,(\l„\\, ‘ 25 % ',c:,' \, 1 .\ � -\_, 37 134 ji, \ c \ \ \\4 V ' ,.0, 'y 77-0 •�V °I") '-'\ \ \ tad CO/ (0 1 N(\ n \ I \ 1 \ ' V-33 133 iCtc. / 1 \I f� af.,.0 / `�0.-1 \ '4-_-,S 5 I' 36? Tom ' �, :j :,c, \\:..„ _o .6 v-W�w o N o+ , %-t 1 yI %) Jed Na l ....„7, o � 9' R;; � / t�.a,e t .ee��Y ( r ) --1 J ' T 3 N f. GROUND WATER STUDY � - A0 o a-- y2N / PROPOSED SURFACE COAL MINE \2_,„----;-_o 2 / /%vim ADOLPH COORS COMPANY, GOLDEN, COLORADO 0 GROUND WATER OBSERVATION: WELL IN COAL SEAM •-, N V ,,(7: �� ' i-+ ISO PUMP TEST IN COAL SEA"' �'' n e a1., ® GROUND WATER OBSERVATION WELL IN OVERBURDEN � � ��, ,1 - d "�.. - f PUMP TEST IN OVERBURDEN �. . : I �Q • PIEZOMETER FOR AQUIFER TEST R'✓✓T : t'22 °C' EXISTING WELL I -'A '1 'w. m,-.-D�-/ J�J • N ?` \ 3 WELL NUMBER • 1 �' v a�' o �' > SCALE: feet cV v v'7 '\ L - , v` 0 2CCO 4000 6CCO i '-��\ _ _ �v \ t� xxxx coal extraction limits pit limits western edge of old Ennis Draw channel Figure 16. Approximate extent of mining. 38 Using an average seam thickness of 6.86 ft, a trench width of lC0 ft, a coal density of 80 lbs/ft3 , and a mean production rate of 510,000 tons/yr, the rate at which the trench is extended is 50 ft/day. On the average, the maximum length of open trench in Pit A will be 3000 ft, a length that will be achieved in some 60 days, assuming the average conditions presented above apply at the outset of mining. For the purposes of pit inflow estimates, it is further assumed that overburden removal in Pit B is initiated at the beginning of the second year and that the trench length is extended at the rate of 50 ft/day. Under these conditions, the maximum length of open trench at any time is 6000 ft. Inflow to the pit will occur from both sides and the ends . However, the area of aquifer exposed on the end of the trench is very small relative to the area exposed on the lateral surfaces of the pit, and inflow from the end of the trench was neglected, therefore. Depending upon the final mining plan, there is one area in Pit A where the eastern extremity of the pit may intersect the old stream deposits in Ennis Draw_ Potential inflow for this case will be discussed subsequently. Regardless of whether the aquifers are confined or unconfined initially, the exposure of the aquifers in the pit will cause the aquifers to become unconfined in the vicinity of the pit. Therefore, the aquifers will respond according to a coefficient of storage (apparent specific yield) characteristic of unconfined materials. Also, exposure of the aquifers in the pit causes the boundary condition on the outflow face of the aquifers to be that of atmospheric pressure. Because individual aquifers in the overburden could not be identified, the interval extend- ing from the bottom of the coal seam to the existing piezometric surface was regarded as the initial saturated thickness. The saturated thickness 39 varies from point-to-point, of course, but it was necessary to use a uniform average value in the computations. The use of a uniform initial saturated thickness does not severely limit the validity of the results , however. Inflow to the pit from all directions will occur when the trench is initiated, and the trench will be extended into overburden that has experienced some drainage, therefore. The difficulties of a rigorous mathematical treatment of this phenomena are considerable. An _stimate of the maximum inflow that can be reasonably expected is made by assuming one-dimensional inflow through the lateral surfaces of the trench. During the initial stages of overburden removal , the length of the trench will increase with time. This was handled by calculating the inflow to the trench in segments, taking into account that inflow into each segment begins at different times. Once the pit reaches maximum length, each new segment of the pit will be advanced into previously drained overburden, and it was assumed that no additional new inflow was induced. Therefore, inflow estimates after the trench has reached maximum length were made as if the position of the trench no longer changed with time. The cumulative volume of inflow from both sides of a trench segment of length L is estimated from Vi = 4L( 12 2 )-1/2 (t-t. )1/2 + goL(t-t. ) (1 ) 1 S Th ya o where Vi = cumulative volume for segment i , (L3) L = length of trench segment i , (L) Sya = apparent specific yield (dimensionless) , T = transmissivity (L2/T) , - h = initial saturated thickness (L) , 0 40 qo = natural flow in undisturbed aquifer per unit of trench length, (L3/LT) ti = time at which segment i came into existence (T) , This equation was derived using a "succession of steady states" approach which accounts for the variable saturated thickness of the aquifer in the vicinity of the pit. The mean discharge (rate of inflow) over a time period is computed by dividing the volume that has accumulated over the period by the duration of the period. Inflow estimates were made by applying equation 1 to trench segments 500 ft in length. At a rate of advance equal to 50 ft/day, a new segment comes into existence every 10 days until a trench length of 3000 ft is obtained. After that time, no new segments are considered because the trench will be advancing into previously drained overburden as explained previously. The cumulative volume for the entire length of open trench at any time is computed by adding the volumes contributed up to the time of interest by each segment. The estimated cumulative volume and rates of inflow are shown in Figure 17 for the first 460 days of operations. The following values were used for the parameters in equation 1 : T = 10 ft2/d (average deter- mined from aquifer tests) , Sya = 0.05 (typical value for clay and shale materials) , ho = 65 ft (average from Fig. 4) , go = 0.08 ft2/d (from measured T and slope of piezometric surface) , and L = 500 ft. The first peak in discharge occurs at the time when the trench in Pit A reaches a length of 3000 ft. The subsequent decline of inflow rate represents the continued drainage to the 3000 ft trench under the influence of progres- sively smaller hydraulic gradients. The second peak occurs as the result - of opening a new trench in Pit B during the first part of the second year 41 laa,t 3 0 '3Wfllon 3AIiVlfWf3 0 O o o to ct 'J al co '7 V' N I • I I 1 1 I I I OO I _-�-1 I CO O -'a. a _8 a- v 0 M O -N M O CO 0 • -V oo N v° we. �o O a _2 a Q � -N -o O (p u E CO O i f I I I 1 1 I I I t 1 I 0 0_ 0 0 0 0 0 o N-O 0 OO 0 0 0 0 0 s{ M N wd6 '1 I 01 3DaVHDSI0 3DVb3AV 42 of mining and includes inflow from the trench in Pits A and B. The rates and volumes of inflow shown in Figure 17 are probably the maximums that can be anticipated. As explained previously, the values of transmissivity obtained from the aquifer tests are believed to be greater -- than the actual values because they reflect the influence of well -bore storage not accounted for in the analysis procedure. Should the actual mean transmissivity be less than the value of 10 ft2/day used in the computations, inflow will be correspondingly less. It may also be that the actual rate of extension of trench length will be less than the value of 50 ft/day used in the computations; if so, the inflow peaks will be less than presented herein. Finally, the computation procedure ignores that, during the period in which the length of open trench is increasing, new increments are being advanced into overburden that has been partially drained by previous segments. This also will cause the inflow to be less than estimated. It should be recognized that the inflow to the trench will be dis- tributed all along the trench in the form of seeps at various points on the high wall and snanating from beneath the spoil . The distributed nature of the inflow will tend to maximize evaporation and it is highly unlikely that inflow will become sufficiently concentrated in the trench to flow as a stream and require removal . It was mentioned previously that a portion of the area designated as Pit A in Figure 16 intersects the area, beneath which, stream deposits associated with the old Ennis Draw exist. Inflow to the east end of the trench could be substantial from these deposits should they be intersected, and it is recommended that special care be taken to prevent significant _ disturbance of the waters in Ennis Draw. The proposals , advanced by Coors, 43 to: 1 ) construct a compacted shale cutoff trench on the east and south edges of the trench area that intercepts the old channel of Ennis Draw, or 2) restrict mining operations to those areas that will not substantially influence the subsurface water in the old channel of Ennis Draw will pro- vide adequate protection. B. Drawdown of Piezometric Surface Due to Pit Inflow The theory leading to Eq. 1 also provides a means for estimating the distance from the pit to points where the piezometric surface will remain essentially undisturbed. The equation is L = ( 3Tt )1/2 (2) Sya where L is the distance from the pit to the point where the drawdown of the piezometric surface is zero, and other symbols are as previously defined. Using T=10 ft2 Sya=0.05, Eq. 2 yields the values of L shown in Table 5. Examples of the predicted shape -of the piezometric surface in the vicinity of the trench are shown in Figure 18. Table 5 . Distance From Pit to Line of Zero Drawdown in the The calculations shown in Table 5 Laramie Formation indicate that the disturbance of the L t ft years piezometric surface in the Laramie 230 0.25 330 0.50 caused by pit inflow will extend less 400 0.75 470 1 .00 than 0.5 miles on either side of the 660 2 1050 5 pit. Therefore, at no time during mining 1480 10 2090 20 should the piezometric surface in the Laramie be disturbed beyond about 0.5 miles from the pit location. This relatively small extent of the influence of the pit is due mainly to the very small hydraulic conductivity of the Laramie overburden, causing the drawdown profile to be very steep in the vicinity of the pit. 44 • 4-, •r O S- CI • O -O V )o • O O O Cr) 8 N a ft w T gW U O a ♦o p -o a 0 0) 0 v rn O 8 II- L W UCI ell Z U O H L t N s_ + 4) N "O O T V C O O 0 8 co N CJ S- CI O O 00 O O O OO cr N 4994 ' 210013 JJ 3A08' 30V32lI1S J1a13WOZ31d 30 II40/3H 45 The distance to which drawdown of water levels would occur in the stream deposits in Ennis Draw, should they be intersected by the pit, can- not be estimated quantitatively, The drawdown due to pit inflow could extend over a very large area depending upon the transmissivity of inter- sected deposits. Again, it is recommended that special care be taken to protect the waters in Ennis Draw from significant disturbance by either of the methods described previously. C. Quality of Mine Inflow The quality of waters presently existing in the overburden and coal aquifers is shown in Table 3. Water seeping into the pit from the high- wall side will be a mixture of water from the coal seam and from the overburden. Because the contribution from the coal seam will be quite small relative to that from the overburden, the quality of the seepage into the pit from the highwall will be essentially that of the existing overburden waters. Seepage from the side of the pit opposite the highwall must pass through the spoils before entering the pit. Experience with the quality of waters passing through spoil banks formed from the Williams Fork form- ation in western Colorado suggests that the effluent water will contain dissolved solids at a concentration about equal to that in water equil - ibrated with and saturating representative samples of the overburden. Similar experience in the Fort Union formation suggests that water saturating spoils will exhibit dissolved solids concentrations exceeding that in saturation extracts by a factor of about 2. Table 6 shows the pH and electrical conductivity (EC) of saturated extracts prepared from composite grab samples taken from 3 cores in the Laramie formation. 46 Comparison of the EC values in Table 6 . EC and pH of Saturated Extracts (Composite samples Table 6 with those for the overburden from Cores) Core No. water samples in Table 3 shows that pH EC @ mmhos/cmcm the existing dissolved solids concen- 83 7.8 4.3 65 7.7 6.9 tration is greater than that in the 101 7.6 6.7 saturated extracts. Based on the previous experience which suggests that spoil water will contain dissolved solids concentrations between 1 and 2 times that in saturated extracts and that the existing waters are already in this range, no appreciable further degradation of water quality is anticipated as the ground water passes through the spoils. Therefore, the quality of pit inflow should be nearly that shown in Table 3 for overburden waters. As previously noted, the water quality is such that the usefulness is probably limited to dust control or other non-agricul - turaT or domestic use. Furthermore, the quantity of inflow is likely to be too small to be effectively concentrated and used. V. Post-Mining Hydrology and Water Quality A. Post-Mining Flow Patterns and Hydrology Following the termination of mining , there will exist a period during which the spoils will tend to resaturate and water levels rise toward the premining values. We have no viable computation procedure for estimating the recovery time. Experience suggests that water levels will probably recover substantially within about 3 years following the termination of mining. In any case, recovery time is of little importance since no use of overburden waters presently exists. Recovery of water levels in the stream deposits in Ennis Draw is a more important consideration since there exist wells completed in these _ deposits in the vicinity of the proposed mine. Again, it is not possible 47 to estimate the recovery time quantitatively. However, it is reasonably certain that no permanent reduction of water levels in the stream deposits will result from mining. The apparently substantial flow from the south will tend to replenish any materials dewatered as a result of the mining pit incising the deposits. Should either of the previously described methods for protecting these waters during mining be adopted, there should be no substantial disturbance of the water levels in Ennis Draw. There is no way by which the hydraulic conductivity of the spoils can be estimated quantitatively. The large clay content in the Laramie formation suggests that the hydraulic conductivity will be small , probably on the same order as that of the re-mining overburden. In this case, the flow pattern through the aquifer will eventually return to essentially the existing pattern. If the hydraulic conductivity of the spoils is less-Than that of the surrounding aquifer, there will be a partial diver- sion of water around the mined area. On the other hand, there will tend to be a concentration of flow through the spoils if their hydraulic con- ductivity is greater than that of the surrounding aquifer. Again, the post-mining flow pattern in the Laramie is of little practical concern since no use of this water is made in the vicinity of the project. Consideration has been given to pushing much of the blow sand mantling the Laramie into the pit before backfilling with spoil . If this is in fact accomplished, it is likely that the resulting layer of sand beneath the spoils will become the major avenue for flow in the mined area. We see no problem with this plan except in the area where the pit has cut through the stream deposits in Ennis Draw. Contact of the sand layer underlying the spoils with the stream deposits would form a hydraulic con- _ nection between the waters in the stream deposits and in the mined area that is much better than existed prior to mining. The consequences of 48 the improved hydraulic connection are not clear. Constructing a compacted shale trench to prevent communication between pit backfill and the deposits in Ennis Draw or restricting mining so that the deposits are not inter- sected is recommended. B. Post-Mining Water Quantity and Quality We believe that the sources of existing ground waters on the lease- hold are located exterior to the site and will not be affected by the mining operations. Further, the disturbance of the overburden should not change the quantity of vertical recharge which is probably negligibly small . Thus , the mining operations should not significantly alter the existing quantities of water passing through the leasehold, once the water levels have recovered. This statement is based upon the assumption that a permanently improved hydraulic connection between waters in Einis Draw and the leasehold is avoided. Based on a comparison of the EC of saturation extracts prepared from composite samples of the overburden with that for existing overburden waters, no further degradation of water quality is anticipated as ground water passes through the spoils. Protection of water quality in the stream deposits in Ennis Draw can be provided by a compacted shale trench in areas where the pit cuts into these deposits, or by not permitting the mining operations to intersect the deposits. 49 VI. Acknowledgements Assistance in the collection of data for this study was provided by several individuals. Especially noteworthy is the assistance of Mr. J. Barrett and Mr. J. A. Brookman of' the Department of Agricultural and Chemical Engineering. Mr. Garland Putnan, Mr. Rodney Cuykendall and Mr. Mike Guttersan extended to us permission to sample wells owned by them and provided us with other information on these wells. Their cooper- ation is greatly appreciated. Hello