Loading...
HomeMy WebLinkAbout20091009 • 8.0 STATEMENT OF ADEQUATE WATER SUPPLY Potable water will be supplied by commercial water service. The Applicant will use water from an existing well on the Morton Property for all operations including but not limited to: sand and gravel washing and processing; dust control and, ready mixed concrete production. An application for a commercial well permit has been filed with the office of the Colorado State Engineer. WATER INFORMATION 8.1 General The Morton Lakes Pit is located west of the South Platte River. Additionally, Big Dry Creek separates mining Stages 1 and 2 and discharges into the South Platte River from the west. Mining at the Morton Lakes Pit will intercept shallow groundwater, which lies • approximately 5 feet below the ground surface. Deeper bedrock,non-tributary aquifers, that underlie the site such as the Arapahoe and Laramie Fox-Hills will be unaffected by the mining operation because of the shallow depth of excavation. Local surface water ponds,ditches, watercourses, and tributaries are shown on the pre-mining map (Exhibit C-1). There will be no adverse impacts to the South Platte or Big Dry Creek because of the Holton Lakes Pit. 8.2 Potential Water Resource Impacts The proposed Morton Lakes Pit will have minimal impacts on the water resources in the area. Prior to dewatering Stages 2, 3,4 and 5, a soil-bentonite slurry wall will be installed around the perimeter of each mining stage. Once the slurry wall in place each mining stage will be de-watered prior to mining. With the slurry wall in place prior to any pit de-watering, adverse impacts to the surrounding alluvium will be minimized. • 2009-1009 Mining Stages 1, located in the south end of the Morton Lakes Pit will not be sealed • off from the surrounding South Platte aquifer. Mining Stage 1 will be dewatered,mined and allowed to fill with ground water following mining. Over the life of the pit, wash fines from the Morton sand and gravel processing plant will be used to backfill Stage 1. The wash fines will be used to create wetlands for the reclamation of Stage 1 8.3 Discharge Permits The proposed mine will be dewatered and operated as a dry mine. Alluvial groundwater from pit dewatering will be discharged into the South Platte and or Big Dry Creek from various locations. The Applicant previously obtained an NPDES discharge permit(Facility No.COG-501501) from the Colorado Department of Health and Environment for the Holton Lakes Pit which will also be used to cover groundwater discharges from the Morton Lakes Pit. Groundwater will be discharged in accordance with the approved NPDES permit conditions. 8.4 Surface Water Management • Runoff from disturbed areas will be managed to protect against pollution of either surface or groundwater through the implementation of a site specific Storm Water Management Plan (SWMP) for the Morton Lakes sand and gravel pit. 8.5 Consumptive Water Use The projected annual consumptive uses of water associated with the proposed Holton Lakes Sand and Gravel Pit and ready mixed concrete production are described below. 8.5.1 4% Moisture Loss in Materials 29.4 acre-feet. 8.5.2 Dust Control 2.0 acre-feet. • • • 8.5.3 Ready Mixed Concrete Production • 10.3 acre-feet. 8.5.4 Water Surface Evaporation 51.0 acre-feet. 8.6 Total Projected Annual Water Consumption 92.7 acre-feet. 8.7 Substitute Supply Plan Ground water depletions of water tributary to the South Platte River, as described above, will be augmented through a Substitute Water Supply Plan(SWSP)approved by the State Engineer for the Morton Lakes Pit. There will be no ground water depletions associated with the proposed Morton Lakes Pit until the Applicant has obtained an approved SWSP from the Office of the Colorado State Engineer. Post-reclamation ground water depletions, if any,will be replaced through a Water • Court approved Plan of Augmentation. 8.8 Hydrologic Balance Overview Introduction The proposed Morton Lakes sand and gravel pit is located in parts of Section 1 and Section 12, Township 1 North, Range 67 West, 6th P.M., Weld County, Colorado. The site is approximately one half mile west of Fort Lupton, south of Colorado State Highway 52. The proposed mining operation is west of the South Platte River. It will affect the South Platte River in the form of groundwater depletions due to evaporation and water uses associated with mining. The impacts to the South Platte River can be mitigated without injury to the vested senior water rights. Mining at the Morton Lakes Sand Pit will last approximately 10 years. The proposed reclamation plan will create four slurry wall sealed pits that will not • be hydraulically connected to the South Platte River alluvial aquifer. The proposed mining plan will also create one unlined pond totaling approximately 19 acres. This pond • will be used during mining; however, it will ultimately be backfilled leaving a 2 to 3 acre shallow pond in the north end of Stage 1 upon completion of mining. The remaining for mining stages will each be sealed prior to mining and have a total surface area of approximately 115 acres. A substitute water supply plan(SWSP)pursuant to C.R.S. 37- 90-137, will be filed with and approved by the State Engineer's Office(SEC)) for replacement of the depletions during the mining phase. Potential Ground Water Resource Impacts Ground Water Wells The Morton Lakes Pit will have minimal impacts on the prevailing hydrologic balance. Sand and gravel mining related impacts to ground water wells near the Morton Lakes Pit will be mitigated through the installation of slurry walls around the perimeter of mining stages 2, 3, 4 and 5 prior to the start of dewatering these stages. Potential ground water impacts associated with mining Stage 1 will be minimal due to the limited time this stage is dewatered and the fact that it will ultimately be backfilled as part of the reclamation plan. At least one year prior to the start of pit dewatering, the Applicant will install up to 10 ground water monitoring wells in order to evaluate ground water fluctuations and the potential for adverse impacts to neighboring wells due to mining. Monitoring wells will be located along the south,west and north permit boundaries. Ground water elevations in the monitoring wells will be measured monthly. In the event that any neighboring wells are adversely affected by pit dewatering the Applicant will promptly take steps to mitigate any adverse impacts. Cottonwood Trees in the Riparian Corridor If necessary, in order to protect cottonwood trees from adverse impacts due to pit de-watering,the Applicant will periodically pump ground water from the dewatered pit to areas where trees are at risk of damage from dewatering. This technique has been successfully used in Colorado for over 30 years to protect cottonwood trees from damage • due to pit de-watering. • • • Post Reclamation Ground water mounding and shadowing associated with the slurry wall sealed portions of the Morton Lakes Pit are not anticipated to produce any adverse impacts to adjacent properties. Potential ground water impacts will be mitigated because of the proximity of Big Dry Creek to sealed Stages 2, 3 and 4. Water elevations in Big Dry Creek will serve to regulate ground water elevations in the alluvium adjacent to each of the above three sealed pits. Water Requirements Water use at the site will include evaporation from exposed groundwater, sand and gravel processing,water retained in material removed from the site,concrete batching and dust control. The mining operation will extract sand and gravel deposits from the South Platte alluvium that is approximately 30 feet deep and this alluvial groundwater system is hydraulically connected to the South Platte River. The depth to groundwater is approximately 5 feet below the surface. • The South Platte River flows from south to north approximately ''A mile east of Morton Lakes. Big Dry Creek intersects the southeast corner of Morton Lakes,between Stages 1 and 4 to the west and north and Stage 2 located southeast of Big Dry. The Lupton Bottom Ditch bisects Stage 4 from its headgate on Big Dry Creek to the north boundary of the Stage. Lupton Meadows Ditch diverts from the Lupton Bottom Ditch on the north side of Stage 4 and flows due north. The Brighton Ditch is located along the south side of the property as well. The Little Dry Creek intersects the Lupton Bottom Ditch to the northwest of the property. The Fulton Ditch is located approximately 2 miles east of the site. The Platteville Ditch diverts from the South Platte downstream of this site. Evaporative losses are dependent on the exposed surface area, which will vary throughout the mining operation. The estimated maximum area of exposed water surface over the life of the mine will be 19 acres. The gross annual evaporation for the site is 43 inches or 3.6 feet,which was taken • from the NOAA Technical Report NWS 33, Evaporation Atlas for the Contiguous 48 • • United States. Monthly evaporation percentages, as suggested by the SEO were used to • calculate monthly evaporation. The Climatology of the United State No. 81 provided the estimated annual precipitation. The annual mean precipitation is 14.90 inches and is estimated to be an average of the Denver WSFO and Brighton weather stations. The effective precipitation is computed to determine the net evaporation from the exposed groundwater. Effective precipitation is calculated as 70%of the average annual precipitation and is 0.9 feet for the Holton Pit. The net evaporation is then determined by subtracting the effective precipitation from the gross evaporation. The net annual evaporation is approximately 2.7 feet,thus the resulting net annual evaporation consumptive use during the mining operation is 51 acre-feet. The other 115 acres of the pit will be lined prior to mining and reclamation and will not require augmentation of evaporative losses. The water retained in the mined material is considered a consumptive use. The anticipated amount of material that will be mined each year is 1,000,000 tons. Assuming 4%moisture content by weight as suggested by the SEO,the total annual depletion is 29.4 acre-feet. There will be approximately 2 acre-feet of water used for dust control. • Concrete will be produced at this site, approximately 50,000 cubic yards or 10.3 acre-feet of water will be needed. The maximum annual consumptive use associated with mining are as follows: • Evaporative Losses= 51 acre-feet • Moisture Retained in Product=29.4 acre-feet • Dust Control=2 acre-feet • Concrete Production= 10.3 acre-feet Total=92.7 acre-feet Water Rights and Replacement Water Replacement water will be provided under the Holton Lakes Substitute Water Supply Plan approved by the SEO. The Applicant has access to a portfolio of water rights and may use any combination of the following to make replacements at the site. • 0.125 shares of Brighton Ditch(estimated consumptive use—24 to 30 acre-feet) • Fulton Ditch water rights and storage water. • • Proposed Agreement with Central Colorado Water Conservancy District to • convert Holton's irrigation wells to an industrial use. Water from Holton's existing irrigation wells may supply water for operational needs including, sand and gravel processing,concrete batching and dust control. The Applicant will maintain a SWSP until the liner is constructed and approved by the SEO. If, after completion of the lined reservoirs, there may be up to 8.1 acre-feet of long-term evaporative depletions if a pond remains in the north end of Stage 1. Any post reclamation depletions will require augmentation under a court approved augmentation plan. Surrounding Water Rights Exhibit G-1 shows a map of all the water rights and permitted wells within 600 feet of the site. The SEO tabulation database was used to identify surrounding wells and water rights shown on the map. Exhibit G-2 is a list of the decreed water rights within 600 ft of the property boundary. Exhibit G-3 is a list of the wells within 600 ft of the property boundary. Although there may be other wells in the area, they are not registered • or permitted with the SEO. In addition, it should be noted that the SEO database does not indicate if a particular well is any longer in active use. This list of wells and water rights has not been verified in the field to determine if they still exist or their actual location. This work will be done when the Substitute Water Supply Plan for Morton Lakes is prepared including the application for the well permit for this gravel pit and the notice requirement to well owners within 600 feet of this site. As required by the SEO,a gravel pit well permit will be obtained before mining for uses pertaining to groundwater at the site. If the use of groundwater at Morton Lakes Pit results in material injury to surrounding wells,the operator of the site will take all necessary actions to remedy the injuries. 100-Year Floodplain The Morton Pit is located in the 100-year floodplain of the South Platte River. A floodplain use permit will be obtained from Weld County before mining commences. • Water Quality • Groundwater will be pumped and discharged to either directly to the South Platte River or indirectly through the Big Dry Ditch. An NPDES Permit has been obtained from the Colorado Department of Public Health and Environment. This permit will remain active while mining operations discharge groundwater from the Morton Lakes Pit. Runoff from disturbed areas will be managed to protect against pollution of either surface or groundwater through the implementation of a site specific Storm Water Management Plan for the Morton Lakes Sand and Gravel Pit. • • • r : . iv v.7..... .. . . r. LEGEND R67 W 4 `'� R66W . - Morton Property Boundary - ••• a m 600 ft Property Buffer r i IIIII o V IIswitt n 6CO ft — --- - * Structures within 600 ft I l I. I ii I i t t A _ - 2 s z, _ - , Set. .1 - - e ei ` ' , � e,� �}., _ , ,� Le ♦ VO `� kg., • i r.e = 1 I 1 16 1 `/Q X. € 1 Q 1 .9 I I J W J - ' 1 �O CT1 —.r I - . II I . • • I • - - . I 1 - a I - _ g .. 1 T1 N 1 t * 1 + - • p s - ♦ 1 ' Morton 1 Property I c ill 9j5to/ I I 0. I I et "Gal 70 x 1 1 S • I4 I N , I I . ' I 1 - I ii i . opi F * 1 a + ..., - 11 • • ...• c .• ,. c1/4iiiii S gig Del 1 •♦ • 4 , �yr ♦ - ♦ . .... - Sec.` 12 ,_ t I . I • B. . -- is... .-r .. - - iiiimppr 1 inch eq Is 1,275.2 feet • .41L I - F -- Feet i alibi .40111st ra.,0 1 ,000 2,000 Applegate EXHIBIT G- 1 Date: 5 Sep 2008 • Group, Job #: 05-142 Water Resource Advisors for the West 1499West120h Ave.Ste 200 Phone:(303)452.6611 Morton Property Drawn By: KCH Denver.CO 80234-2728 Fax: (303)452-2759 www.Apple.'gats roup.com e-mail:mfo@applegategroup.com • • • Exhibit G-2 Surrounding Water Right Structures(may include wells or water rights that have been decreed) These structures are listed within 600 ft of Morton Property as of 9/7/2006 from SEO database However,these structures have not been field verifed and the actual location of these structures may be different than shown on the map No. ID STRUCTURE_ OWNER_NAME Dec Capacity TS RNG SEC Q160 Q40 Q10 COUNTY Structure Type 1 6598 HOLTON WELL 1-13697 HOLTON,TOM 1.55 C I N 66 W 7 NW SW SW WELD Well or Well field 2 6599 HOLTON WELL 2-13698 HOLTON,TOM 1.11 C I N 66 W 7 NW NW NW WELD Well or Well field 3 6602 HOLTON WELL 5-2216-F HOLTON,TOM 1.55 C 1 N 66 W 7 NW SW SW WELD Well or Well field 4 6920 LAMBRECHT WELL 1-12790 MORTON,MARGARET 2 C 1 N 67 W 12 NE SW SW WELD Well or Well field • • i r 0 Exhibit G-3 Surrounding Wens These wells are listed within 600 ft of Morton Property as of 7/1/2008 from SEO database However,theme wells have not been field vented and the actual location of these structures may he different than shown on the map The status code below shows"record changes"that may refer to an existing well and potentially should not be counted as another well. No. Permit No. Suttix Statue Code Use NAME C/O ADDRESS CITY STATE ZIP Record change. A portion of the PO BOX 693 I 12790 It file was modified/corrected. Irrigation MORTON MARGARET V FT LUPTON CO 80621 2 182106 Resubmitted date. Domestic,Stock SCHROEDER BRENT A MARY 1100 DENVER AVE rr LUPTON CO 80621 3 162966 Resubmitted date. Well permit issued. Domestic MORTON MARGARET V PO BOX 693 FT LUPTON CO 80621 Well permit expiration dale PO BOX 693 4 162797 Resubmitted date. extended. Irrigation MORTON MARGARET V FT LUPTON CO 80621 Record change. A portion of the 12032 HWY 52 S 13697 R file was nodifiedharrected. Well permit issued. Irrigation HOLTON TOM FT LUPTON CO 80621 Verbal approval granted to well 12032 HWY 52 • 6 96429 VE construction contractor. Irrigation HOLTON TOM FT LUPTON CO 80621 Household, SCHROEDER BRENT H&MARY 1100 DENVER AVE 7 213063 Well permit issued. Monitoring well A FORT LUPTON CO 80621 Industrial, WRIGHT INVESTMENT GROUP 1011 PJ.F.VF,Ffff1 AVE 8 61793 F Resubmitted date. Well permit issued. Commercial INC GREELEY CO 80631- WRIGHT INVESTMENT GROUP 9 274247 Resubmitted date. Well permit issued. Commercial INC C/O DONALD WRIGHT BOX 73 FORT LUPTON CO 80621- • • • Permit No.COG-500 Facility No.COG-501 Pa! Colorado Discharge Permit System Regulations CERTIFICATION . under GENERAL PERMIT FOR SAND AND GRAVEL MINING AND PROCESSING(SIC No:1440,]442) Category 07,Subcategory IA, General Permits,Sand& Gravel—Process Water&Storm water, S270 Annual fee This certification specifically authorizes Ready Mixed Aggregates,to discharge as described below and in accordance with the Gene: Permit for Sand and Gravel Production Operations. All correspondence relative to this facility should reference the specific facility number,COG-501501. Permittee Contacts Ready Mixed Aggregates Nathan Merkinson,Plant Manager,303-659-0630 4395 Washington Street Bill Timmons,General Manager,303-659-0630 Denver,CO 80216 Project Name,Activity and Location Holton Lakes Sand and Gravel Pit—The discharge will consist of stormwater and process water discharges including pit dewatering from the mine located at 12300 Highway 52 in Fort Lupton(Weld County)Colorado. Discharge Points The discharges(001A-006A)are located at Latitude 40.08°N,Longitude 104.83W. Outfall Description and Treatment Flows The discharge from the"Stage P"area is Avg =3.0 MGD 001 A sent to a settling pond prior to entering the Max.=4.6 MGD South Platte River 002A The discharge from the"Stage 2-C"area Avg.=3.0 MGD is sent to a settling pond prior to entering Max.=4.6 MGD • the South Platte River The discharge from the northwest corner Avg.=3.0 MGD 003A of the"Stage 3"area is sent to a settling Max.=4.6 MGD pond prior to entering the South Platte River The discharge from the west side of Avg.=3.0 MGD 004A "Stage 3"area is sent to a settling pond Max.=4.6 MGD prior to entering the South Platte River The discharge from the"Stage 4"area is Avg.=3.0 MGD 005A sent to a settling pond prior to entering the Max.=4.6 MGD South Platte River The discharge from the"Stage 5" area is Avg.=3.0 MGD 006A sent to a settling pond prior to entering the Max.=4.6 MGD South Platte River The discharges are to the North Platte River,Segment 1 b of the Middle South Platte River Sub-Basin,South Platte River River Basin,wh can be found in the Classifications and Numeric Standards for the Gunnison River Basin(Regulation 38; last update effective March 2008).Segment lb is designated Use Protected,and is classified for the following beneficial uses:Recreation Class la;Aquatic Life,Clas (Warm);Water Supply;and Agriculture. • ISSUED AND EFFECTIVE: MARCH 11,2008 EXPIRATION: SEPTEMBER 30,2007 Administratively Extended • • Permit No.COG-500000 Facility No.COG-501501 Page l b • Permit Limitations and Monitoring Requirements Discharge Limitations Maximum Concentrations Monitoring Parameter Sampleype T 30-Day 7-Day Daily Max. Frequency Average Average Flow,MGD Report NA Report Weekly Instantaneous or Continuous Total Suspended Solids, 30 45 NA Monthly Grab mg/1 Oil and Grease,mg/I NA NA 10* Weekly Visual* pH,s.u.(Minimum- NA NA 6.5-9.0 Monthly In-situ Maximum) Total Dissolved Solids ** ** ** ** ** mg/1 Total Phosphorus mg/I *** *** *** *** *** *There shall be no visible sheen. **Not required,applicable only to waters of the Colorado River Basin- ***Not required applicable only to waters with a control regulation for Phosphorus Other Conditions The permittee will need to develop and implement a Stormwater Management Plan(SWMP)for this facility. As a condition of this permit, a copy of the SWMP must be kept on site and provided to the Division upon request. The permittee is encouraged to read the general rationale for an understanding of how this permit was developed and read the permit to see what requirements exist. aoThe General Sand and Gravel Mining and Processing Permit is attached. If the permittee has questions related to this certification,contact the permit writer. Permit Writer Erin Scott 303.6923506 March 5,2008 9.0 EVIDENCE OF ADEQUATE SEWAGE DISPOSAL The building that will serve as the office/scale house and employee meeting room for the sand and gravel processing plant and the ready mixed concrete plant personnel has an existing sewage disposal system. If required,the applicant will apply to the Weld County Health Department for an ISDS Permit for the office/scale house. Portable restrooms will be used to provide sanitary services for employees working at the mine face in Stages 2, 3,4 and 5. A Hello