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Home My WebLink About921312.tiff Mr. Rick Hoffman Page 3 May 4 , 1992 Doty & Associates final cover. Prior to filling, the native soils were to be scarified and recompacted to provide a one-foot thick liner. In addition, the design provided for three wells to detect and collect leachate; the wells were located at low points in the liner. Also, a perimeter ditch system to collect leachate was designed. Requirements for environmental monitoring (ground-water and subsidence monitoring) were added for the first time. Hours of operation were eight hours per day, six days per week. 1988 Design The 1988 design (IC, 1988) was prepared to fulfill some of the requirements of the Certificate of Designation and SUP #400 transfer from Colorado Landfill, Inc. , to Laidlaw Waste Systems, Inc. The 1988 design modified the orientation of the ridge along the top of the designed final contours; otherwise, the fill geometry and total area to be covered by refuse are very similar to the 1982 design. A new excavation plan was prepared for areas not already covered by refuse in order to provide sufficient soil for daily, inter- mediate, and final cover. The final cover thickness was increased from two feet to 3 . 5 feet (3 feet of compacted clayey soil and 6 inches of topsoil) . Prior to filling, the native materials (soil or bedrock) were to be scarified and recompacted to provide a 6-inch thick liner (instead of the one foot thick liner previously required) . In addition, the design provided for four leachate detection/collection wells located at low points in the liner (as opposed to the three wells planned in the 1982 design) . The perimeter ditch system to collect leachate was removed from the design. The 1988 design included specifications for environmental monitoring (ground-water, leachate, subsidence and explosive gas monitoring) . Hours of operation were sixteen hours per day, seven days per week (as opposed to eight hours per day, six days per week) . 1991 Design The 1991 design (Golder, 1991) is intended to bring the facility into compliance with the new federal regulations (Subtitle D of RCRA) . The total area to be covered by refuse is similar to that of the 1988 design (smaller because the property line setback has been increased from 50 to 100 feet and a sedimenta- ID 921312 Mr. Rick Hoffman Page 4 May 4 , 1992 Doty & Associates tion pond will be constructed in the southwest corner of the site) . The key features of the 1991 design are a three foot thick compacted clay liner overlain by a 60 mil HDPE geosynthetic mem- brane. The membrane is covered with a 12-inch thick drainage layer which leads to four new leachate collection sumps (one of the 1988 detection/collection wells has already been installed) . In addition, the facility will be capped with a final cover system consisting of four feet of soil. In order to make these improved environmental controls economically feasible, the geometry of the fill was changed and the highest portion of the fill raised to 5334 feet. A new excavation plan was prepared for areas not already covered by refuse in order to provide the soil needed for the various covers. The 1991 design (like the 1988 design) includes specifications for environmental monitoring (ground-water, leachate, subsidence and explosive gas monitoring) . Hours of operation are anticipated to be fifteen hours per day, six days per week (although twenty-four hours per day, seven days per week is the requested allowable schedule) . COMPARISON OF DESIGNS Each of the designs has made some changes to the operational features at the site. The key features of the designs are summarized on Table 1. Probably the most significant changes occurred with the 1982 design when the fill was expanded to cover the entire site and the disposal volume increased from 4 . 2 to 16. 3 million cubic yards. The 1982 design also provided for a leachate collection system and environmental monitoring. A special use permit was issued which obliquely authorized this change (SUP #534 : 82 : 49) ; however, the permit really dealt with the adjoining Pratt property. The 1988 design was very similar to the 1982 design. The only differences involved a slight change to the overall geometry of the fill, a thinner liner, a thicker final cover, and an additional leachate detection/collection well . This design was reviewed by the County and SUP #400 (showing the 1979 design) was transferred to Laidlaw. Apparently, the County did not consider the design changes between 1979 and 1988 to be material deviations (see more on this topic below) . The 1991 design is actually rather similar to the 1982 and 1988 designs, in spite of the fact that the fill will extend to elevation 5334 . The total site capacity is increased from 16. 3 Ire LO's 3 Mr. Rick Hoffman Page 5 May 4, 1992 Doty & Associates to 23 . 2 million yards (a much less significant increase than the increase from 1979 to 1982) . This capacity increase is rather small given the height increase; the relatively small increase results from a reduced acreage to be covered by refuse (area is sacrificed for a sedimentation pond and an increased property line setback) . In addition, the excavation is limited to areas not already covered by refuse (this limits the volume of cover soil that can be developed on-site) . The other changes are consistent with earlier modifications, which generally tend toward more and better environmental controls. NEED FOR AMENDED SPECIAL USE PERMIT The need for an amended special use permit hinges on whether the 1991 design constitutes a "material deviation" from the 1979 permit; however, material deviation is not specifically defined in the County regulations. The use of the property has been consistent over the years and will not change under the 1991 design. Thus, the only change that might constitute a material deviation is the fill geometry change. However, SUP #400 clearly states in Note 8 that the final geometry of the fill depends on the availability of suitable material for use as cover and that the final geometry is likely to vary from the contours shown on the permit. I trust that this material and discussions meet your needs. Please call if you have questions or need additional informa- tion. Sincerely, DOTY & ASSOCIATES Benjamin P. D y, P.E. Mr. Rick Hoffman Page 6 May 4, 1992 Doty & Associates REFERENCES Golder, 1991, Design and Operations Plan for the Denver Regional Landfill (South) , Weld County, Colorado, prepared for Laidlaw Waste Systems (Colorado) , Inc. , prepared by Golder Associates Inc. , Project No. 913-2324 . 003 , September. IC, 1988, Laidlaw South Landfill, Design and Operations Plan, prepared for Laidlaw Waste Systems, Inc. , prepared by Industrial Compliance, Inc. , IC Project No. 2-1803 , March 28 . Nelson, 1979, Operations Plan for Southwest Weld County Land- fill, prepared for Colorado Landfill, Inc. , prepared by Nelson Engineers, September 24 . Nelson, 1982 , Operations Plan for Pratt Property Landfill, prepared for Colorado Landfill, Inc. , prepared by Nelson Engineers, Project No. 2017 , November 12 . SOLID WASTE DISPOSAL SITES USE BY SPECIAL REVIEW APPLICATION Department of Planning Services, 915 Tenth Street, Greeley, Colorado 50631 Phone - 356-4000 - Ext. 4400 Cue Number USR-972 Date Received October 2 190: Application Checked By RDA/CAC/WS Mylar Plat Submitted Application Fee $4,700.00 Receipt Number 64593/accounting Recording Fee Receipt Number TO BE COMPLETED BY APPLICANT: (please print or type, except for necessary signature) d I (we), the undersigned, hereby request a hearing before the Weld' County Planning Commission and Weld County Board of County Comissionera concerning the proposed Use by Special Review Permit on the following described unincorporated area of Weld County, Colorado: Wl/2 NE1/4 LEGAL DESCRIPTION OF SPECIAL REVIEW PERMIT AREA: E1/2 NW1/4,/Section 29 T 1 N, R 68 W LEGAL DESCRIPTION of contiguous property owned which Special Review Permit is proposed: Section T N, R W Property Address (if available) PRESENT ZONE A OVERLAY ZONES Geologic Hazard TOTAL ACREAGE 1b0 acres PROPOSED LAND USE Sanitary landfill EXISTING LAND USE Sanitary landfill SURFACE FEE (PROPERTY OWNERS) OF AREA PROPOSED FOR THE USE BY SPECIAL REVIEW PERMIT: Name: Laidlaw Waste Systems (Colorado), Inc. Address: P. 0. Box 320 City: Erie, CO Zip: 80516- Hone Telephone: Business Telephone: 673-9431 Name: Address: City: Zip: Home Telephone: Business Telephone: APPLICANT OR AUTHORIZED AGENT (if different than above): Name: Laidlaw Waste Systems (Colorado) Inc. Address: p. 0. Box 320 City: Erie, CO Zip: 80516 Home Telephone: Business Telephone: 6/3-9431 List the owner(s) and/or 1 of mineral rights on or under the subject properties of record. Hemet (See Affidavit attached to Use by Special Review) Address: City: Zip: .4--• Name: Address: City: Zip: I hereby depose and state under the penalties of perjury that ell statements. proposals and/or plans submitted with or contained within the application ere true and correct to the best of my knowledge. COUNTY OP Veld ) STATE OF COLORADO ) LAIDLAW TE S TEMS (COLORADO) INC. By: a �4+Q.(L�� I'sx+;h4 Site ref Authorised Agent 's �.4,4 Ritk Hoffman ,,:tr •h jmd sown to before as this cil/1'.Q of O(�CQ-Cit-.- 19 9/. tt r• /� e, :445414 +"�'Tj:�:ei1).. ,C.tt dc-n -21.7141•(• i pV,Q .iiG :p,, IOTA, `PUBLIC .Ifyit:......•lid //AV �.1)7!eopalps fom expire in e,,.,,1.. USE BY SPECIAL REVIEW PERMIT FOB THE DENVER REGIONAL LANDFILL (SOUTH) WELD COUNTY, COLORADO JAffaffAff (Golder Associates, Inc. 013-2324.003 SEPTEMBER 1991 gL Golder Associates Inc. E7CONSULTING ENGINEERS USE BY SPECIAL REVIEW PERMIT APPLICATION FOR TIIE DENVER REGIONAL LANDFILL (SOUTH) Submitted to: Laidlaw Waste Systems, Colorado, Inc. 2340 S. Arlington Heights Road, Suite 230 Arlington Heights, Illinois 60005 Distribution: 40 Copies - Weld County Planning Department 4 Copies - Laidlaw Waste Systems, Inc., Arlington Heights, Illinois 2 Copies - Golder Associates Inc., Lakewood, Colorado 1 Copy - Doty & Associates, Golden, Colorado 1 Copy - SubTerra Inc., Redmond, Washington 1 Copy - Fred Otis, Shade, Dolye, Klein, Otis & Frey September 1991 913-2324 GOLDER ASSOCIATES INC.•200 UNION BOULEVARD.SUITE 100.LAKEWOOD(DENVER).COLORADO.U S .80228•TEL.13031980-0540•FAX(303)985.2080 OFFICES IN UNITED STAI ES•CANADA•UNITED KINGDOM •SWEDEN•GERMANY•ITALY•AUSTRALIA September 1991 i 913-2324 TABLE OF CONTENTS Page 1.0 INTRODUCTION 1 2.0 DESCRIPTION OF OPERATION AND USE 2 2.1 Use 2 2.2 Proposed Operation 3 2.2.1 Environmental Controls 3 2.2.2 Environmental Controls Comparison Summary 5 2.2.3 Vertical Expansion 6 2.2.4 Site Characterization Investigation 6 2.2.5 Site Characterization Conclusions 7 2.2.6 Miscellaneous 9 2.3 Need for Proposed Use 9 2.4 Surrounding Land Uses 10 2.5 Distance to Residential Structures 10 2.6 Number of Users 11 2.7 Employee Requirements and Operation Schedule 11 2.8 Water Source 11 2.9 Access Routes 11 2.10 Vehicular Traffic 12 2.11 Sewage Facilities 13 2.12 Fire Protection 14 2.13 Types and Numbers of Animals 14 2.14 Waste, Stockpile, or Storage Areas 14 2.15 Storm-Water Management 14 2.16 Removal and Disposal of Debris, Junk and Other Wastes 15 2.17 Landscaping Plans and Erosion Control 15 2.18 Reclamation Procedure 16 2.19 Construction and Start-Up Schedule 16 3.0 SUPPORTING DOCUMENTS AND STATEMENTS 17 3.1 Need for the Facility Within the Proposed Area of Service 17 3.2 Consistency With the Weld County Comprehensive Plan 17 Golder Associates C 06.39 September 1991 ii 913-2324 TABLE OF CONTENTS--Continued Page 3.2.1 Agricultural Goals and Policies 18 3.2.2 Urban Growth Boundary Goals and Policies 20 3.2.3 Environmental Quality and Natural Resources Goals and Policies 20 3.3 Consistency With the Intent of the District in Which the Use is Located 23 3.4 A Statement Explaining What Efforts Have Been Made in the Location Decision for the Proposed Use to Conserve Productive Agricultural Land in the Agricultural-Zoned District 23 3.5 Protection of Health, Safety and Welfare of the Inhabitants of the Neighborhood and the County 23 3.6 Compatibility With Surrounding Land Uses 23 3.7 Compatibility With Future Development 24 3.8 Overlay Districts 24 3.9 Water Supply 24 3.10 Property Interests 24 3.11 Noise Report 25 3.12 Soil Report 25 3.13 Adjacent Property Owners 25 3.14 Mineral Owners and Lessees 25 LIST OF TABLES Table 1 Traffic Survey Table 2 Site Soils LIST OF FIGURES Figure 1 Site Location and Vicinity Map Figure 2 Vicinity Map Figure 3 Plot Map LIST OF APPENDICES Appendix A Original Special Use Permit and Certificate of Designation Appendix B Traffic Survey Appendix C Well Permit Appendix D Copy of Legal Instrument Showing Applicant's Interest in the Property Appendix E List of Property Owners Appendix F List of Mineral Owners and Leases Golder Associates oFrn September 1991 1 913-2324 1.0 INTRODUCTION -Phis Amended Use by Special Review Permit (the "Amended USR") Application is for the redesign of a solid waste disposal facility known as the Denver Regional Landfill South which is located in Section 29, Township 1 North, Range 68 West of the 6th P.M., Weld County, Colorado (the "Property"), and which presently holds an existing Certificate of Designation and Special Use Permit No. 400 ("SUP 400"). The Property is owned by the Applicant, Laidlaw Waste Systems (Colorado) Inc. ("Laidlaw"). The reason Laidlaw is requesting a change in the SUP 400 is to provide for a vertical expansion and to upgrade their facility to current Environ- mental Protection Agency (EPA) guidelines. The surface area of this Amended USR Application is within the geographical boundary of SUP 400. The vertical expansion will simply add a longer life to the existing solid waste disposal facility. SUP 400 was originally issued by Weld County in December 1979 (see Appendix A). Laidlaw acquired the Property on January 1, 1988, and submitted a Design and Operations Plan on March 28, 1988. This Amended USR Application, while adding vertical expansion, promises in exchange to provide significant additional protection to the environment beyond the current requirements of the Colorado Department of Health. The Design and Operations Plan is included as part of this Amended USR Application. Much of the operational information required by the Procedural Guide is included in greater detail in the Design and Operations Plan. This Application is organized according to the format presented in the Use by Special Review Procedural Guide issued by the Weld County Department of Planning Services. Section 2.0 -presents a description of the proposed operation and use, as required by Item 2 of the application ✓equirements specified in the Procedural Guide. Section 3.0 provides information regarding the consistency of the proposed use with the Weld County Comprehensive Plan and the Weld County Zoning Ordinance as specified in Item 3 of the application requirements. Section 4.0 includes the Use by Special Review Permit Plan Map and Section 5.0 lists the references used to prepare this Application. -Golder Associates �� ?� ✓7._ w2r September 1991 2 913-2324 2.0 DESCRIPTION OF OPERATION AND USE Descriptions of the use, the need for the use, types of surrounding land uses, traffic and access routes, fireprotection, storm-water management, and other related activities are presented in this section. 2.1 Use The Property is presently permitted under SUP 400 by Weld County as a solid waste disposal site and facility. The change requested by this Application will allow a vertical expansion on a portion of the Property and, in exchange for such vertical expansion, the Applicant will upgrade the existing design to comply with current EPA guidelines. The Property will continue to be used for disposal of residential, industrial and commercial non-hazardous, non-radioactive, solid wastes. -Refer to the Design and Operations Plan for additional information on the types and restrictions on wastes to be disposed of at the site. The Property is located approximately 1.5 miles southeast of Erie, Colorado, on the East Half of the Northwest Quarter, and the West Half of the Northeast Quarter of Section 29, Township 1 North, Range 68 West, as shown in Figure 1, Site Location and Vicinity Map. The Property consists of approximately 160 acres of which approximately 56 acres on the northern half of the Property contain waste that has already been placed and covered with one to three feet of soil cover material. Portions of the west, north and east slopes of the existing fill contain final cover. The remainder of the site contains areas which have been excavated to provide borrow material and soil which has been stockpiled. Golder Associates DnE33 September 1991 3 913-2324 2.2 Proposed Operation 2.2.1 -Environmental Controls Briefly, the Applicant's proposal is to-modify the design and operation of the site to include some significant improvements to the environmental controls. Specifically, the modified design includes the following: 1. All of the remaining virgin ground (approximately 70 acres) will be lined with a composite liner system consisting of three feet of low permeability _compacted clay overlain by a geomembrane (60 mil high density polyethylene). This is a significant improvement over the currently approved six-inch compacted -clay liner. 2. The entire composite liner will be covered with a leachate collection system (complete sand drainage layer with laterals and-headers) leading to four sumps from which leachate can be removed should any develop. The currently approved design has four leachate detection/ removal wells, but it relies on flow through the refuse to low points on the top of the clay liner for leachate collection. 3. The liner and the leachate collection systems have been designed with sufficient slope (4 percent) that the systems will continue to function properly even if subsidence occurs toward the mine which underlies the site. The potential subsidence was estimated using the results of strength testing of mine pillar, roof and floor materials collected during an investigation of site characteristics performed specifically to support the re-design. In addition, the design includes structural and hydrologic plugs for the two shafts and a decline tunnel. The currently permitted plan is not designed against potential subsidence and provides plugs for the two shafts but not the decline. 4. The final cover will consist of two feet of compacted clay, overlain by 1.5 feet of random soil cover and 0.5 feet of topsoil. This results in a total final cover thickness of four feet (the currently permitted thickness is three feet). The topsoil will be vegetated with a _grass mixture recommended by the U. S. Soil Conservation Service and with native shrubs (e.g., sage brush and rabbit brush) on ten foot centers. 5. The final cover slopes will be broken by fifteen foot wide benches approximately every forty vertical feet to reduce the velocity of run-off and thereby reduce _,older Associates �cinvrya September 1991 4 913-2324 erosion -of the cover. In addition, all run-off from the site will be routed to a sedimentation basin. The currently permitted design does not include either of these features. 6. The-buffer zone between the refuse anti the property lines has been increased from fifty to one hundred feet. 7. A new gas control system-has been developed that includes horizontal collectors running into the fill which will be constructed as fillingTrogresses, as well as the more conventional vertical collectors called for in the current design. This system is capable of either active or passive gas extraction and the gas can be used for power generation, flaring nr passive venting. 8. A-new groundwater monitoring system will be used to monitor the performance of the fill (the wells have already been installed as part of the site characteriza- tion). The currently approved system consists of eleven wells; however, only three of these contain water. S Colder Associates 'L2! September 1991 5 913-2324 2.2.2 Environmental Controls Comparison Summary Thefollowing is a summary of the_comparisons to the environmental controls being Proposed in this Amended-USR Applicationas distinguished from the existing design under SUP 400: EXISTING DESIGN NEW DESIGN UNDER UNDER SUP 400 AMENDED USR APPLICATION 1. 6" recompacted clay liner with 1. 3-feet thick clay liner with a 1 x 10' permeability of 1 x 10-6 cm/sec or cm/sec or less permeability ov_crlain less. by a 60 mil. HDPE Geomembrane liner (composite liner system). 2. Has a minimum leachate _collection 2. 12-inch sand drainage layer over the layer or sump collection system. _composite liner system will collect liquids which may migrate through -refuse and collect precipitation. 3. Minimal surface water control 3. Comprehensive -erosion control and structures. surface water control structures will be-built and designed for the 100-year storm. 4. No gas control plan. 4. Gas collection system will be constructed to _collect and flare landfill gas after closure. 5. Design doesn't address subsidence 5. Pit sloped and _designed to assume issue. worst case subsidence scenario. 6. Minimal -remediation of shafts and 6. Detailed engineering design and tunnel to Columbine Mine. analysis for remediation. 7. Minimal requirements for duality 7. Quality assurance and quality control control during construction of liner. plan to -ensure Properly _constructed liner and_cover. Golder-Associates September 1991 6 913-2324 2.2.3 Vertical Expansion In addition to the improved environmental controls, the new design provides for increased disposal capacity together with sufficient-excavation to produce the soil needed for cover material. The-permitted air space (available for refuse and _daily/intermediate cover) will be increased from 1-4.3 to 20.7 million cubic yards (approximately 45 percent). Because approximately 3.5 million cubic yards of refuse and cover have been placed under the existing permit, the available capacity for future filling will be approximately 17.2 million cubic yards (remaining air space is increased by 60 percent). The top of the new cover will be at elevation 5334 (approximately 94 feet-higher than the-currentrlesign) and the average top of the liner will be at elevation3100 (approximately 5D feet deeper than the current design). The top of theliner is at least fifteen feet2bove the uppermost bedrock-groundwater system and is approximately 30Dfeet above the top of the Laramie-Fox Hills, the aquifer used for water supply in-the area. 2.2.4 Site Characterization Investigation The new design is based on extensive on-site investigation. Thirty-six borings and wells had been drilled at the site _prior to 1-991. During the first half of 1991, the following additional investigative work was performed: ► Auger drilling, continuous sampling and core drilling of 14 boreholes; ► Geophysical lagging of the bedrock boreholes; ► Installation of fourteen new monitoring wells--four in-the soil (the S-100 series), nine in the Laramie Formation bedrock (the S-200 series),and one at the base of the refuse along the eastern property boundary (S-107); ► Rotary drilling and coring of four deep boreholes to address subsidence issues related to coal mining beneath the site (S-1 through S-4); ► Packer testing of six boreholes to_determine in situ-hydraulic conductivity; Golder Associates September 1991 7 913-2324 ► Well development and water level recovery monitoring in the new monitoring wells; ► Drilling, installation and development of a water supply well completed in the Laramie-Fox Hills Aquifer; ► Rotary drilling and installation of six piezometersin the southern half of the site (PZ-1 through PZ-6); and, ► Monitoring of groundwater levels in all of the wells and piezometers. 2.2.5 Site Characterization Conclusions This work and the conclusions-based thereon are-presented in detail in thesite characterization report; however, the conclusions can be summarized as follows: 1. Landfilling is consistent with current land uses in the area which are past on-site and off-site underground coal-mining withassociated surface operations, farming, the Erie Airpark residential/airport operation, an auto salvage yard, rural- residential use, and several disposal operations (including the landfill currentlyin operation at the site). 2. There are no perennial streams or ponds within the site boundaries. 3. Soils-are generally silty_clays with a trace to some sandand are of lowplasticity; soil thickness ranges from about 1.5 to 17 feet. There is very little_perennial saturation of the soils. The occurrence of water in the soils appears to be controlled by increased infiltration atareas of surface water concentration where there are also relatively thick soil deposits. Saturation of soils probably occurs periodically_elsewhere, but only in response to precipitation event. The-hydraulic conductivity of the soils is generally low (in the range of lx10-6 to 1x1O5 centimeters per second). 4. The uppermost bedrock is the upper Laramie Formation consisting primarily of claystone, with significantly lesser amounts of siltstone,sandstone,_coalandiela- tively thin layers of highly _cemented, _ferruginous siltstone -known locally as ironstone. The geologic structure is that of a mild dome plunging to the south- Golder Associates S.?-0_6 "3 September 1991 8 913-2324 east; there are no faults on-site. The hydraulic conductivities of the bedrock materials are as follows: Hydraulic Conductivity Material (centimeters per second) Claystone 7 x 10' Siltstone 1 x 10-6 Sandstone 6 x 19"5 Coal 3 x 10-5 Groundwater occurs in two or three hydraulically isolated and laterally continuous systems within two coal horizons and one sandstone layer. Because of structural control, the uppermost aquifer on the eastern talf of the site is a_coal known as the No. 6 Coal. _However, on the western half of the site, the No. 6 Coal is unsaturated and the uppermost aquifer isin a deeper sandstone and coal. 5. The regional aquifer is the Laramie-Fox-Hills which begins at-a depth of375 feet below ground and is approximately 343 feet thick. The top of the LaramieFox Hills is approximately 85 feet below the coal mining horizon (290 feet below ground); the materials separating the -mining -horizon and the aquifer consist mostly of non-fractured claystone with some coal -horizons. The water in the Laramie-Fox Hills is under confinement, with a water leveLrise ofabout 1/8 feet above the top of the aquifer. Groundwater flow in the Laramie-fox Hills is to the east-southeast under a gradient of-approximately 0.006. 6. The site is well located from the point of view of geologic and hydrologic hazards. There are no flood plains or wetlands at the site, and there is no evidence of recent slope instability, faulting, folding, 7ockfall or erosion. The site is not located in a seismic impact zone as _defined in the EPA regulations. Based one series of worst case assumptions, a maximum subsidence of two feet toward the old coal mine beneath the site_could occur, with a-maximum slope change of 1.6%; however, subsidence of this magnitude is Considered unlikely because of the extreme_conservatism of the analytical assumptions. Subsidence is substantially complete in the high-extraction area away from the shafts. 7. Contamination of the environment by the operation is considered very unlikely given the suitability of the siteand the operations plan. The characteristics of the site that make it suitable for landfilling are the absence of surface water, the low hydraulic conductivity bedrock and soil, and the relatively large depth to groundwater. Operational factors that minimize the potential for contamination -Golder Associates September 1991 9 913-2324 are the construction of a complete composite liner system consisting of compacted clayey material overlain by a geomembrane liner, which is in turn covered by a complete leachate collection system. In addition, daily cover consisting of low hydraulic conductivity soils will be placed.promptly and the entire site will be covered with a well-compacted final soil cover. The major conclusion of the -site characterization is that conditions at the site meet the site standards for new facilities described in Section 4.1 of the State of Colorado solid waste regulations and that a sanitary landfill can be operated at the site in an environmentally sound manner. 2.2.6 Miscellaneous The new operations plan provides for routine monitoring of environmental conditions. Groundwater, leachate anti explosive gas concentrations will-be monitored on a quarterly basis for the life of the facility and en a quarterly and semi-annual basis-for a 15-year post closure care period. Groundwater will be monitored for the parameters specified in the Colorado Department of Health Regulations and the results will be evaluated using a statistical procedure described in the sitecharacterization report. Reports of each monitoring event will-be prepared and submitted to Weld County and the State of Colorado. Other facilities associated with the proposed site include-agatehouse located on the-main access road at the entrance, along with an adjacent building containing the driver-break room. The landfill-has a machine shop which is used to maintain vehicles and also houses offices for site personnel. The site perimeter is currently enclosed with an eight-foot tall mesh fence. 2.3 Need for Proposed Use The existing Laidlaw-owned landfill facility currently serves Boulder County and the southern portion of Weld County as well as the northern Denver metropolitan area. There is a significant Golder Associates S70633 September 1991 10 913-2324 need for geologically sound and adequately designed landfills to service Weld County. In Colorado and the Front Range in particular, the facts relating to waste management are that: (I) existing disposal sites are diminishing, (2) waste generation rates are increasing, and are predicted to continue with that trend, (3) recovery of materials from the waste stream is not great, and (4) a strong need exists to innovativelyand effectively approach waste management. Considering the different factors involved, the need for a long-term disposal facility for Weld County can be provided with the approval of this Amended USR Application. This Application should be approved because of the significant upgrades to environmental controls that are proposed (see Section 2.1 above). The Amended USR Application-addresses the needs for a well-suited landfill in southern Weld County. The-site-exceeds the EPA Subtitle DRegulations2nd the setting makes it an excellent candidate for an-environmentally-sound landfill (see Section 2.1 above). 2.4 Surrounding Land Uses The Property is located_directly south of a landfill operated by Laidlaw known as the "Denver Regional Landfill (North)." To the east of the site is a closed25-acre landfill that is known-as the Pratt Property. The Pratt Property has been brought to final grade and a final cover-has been constructed over the site. Other Property directly surrounding the site is agricultural. Other uses in the vicinity of the site include dry land farming, an auto salvage yard that has been in operation for many years, Erie Airpark, limited residential uses, and oil and gas production. 2.5 Distance to Residential Structures The approximate distance to the only off-site residential structures within one mile of the Property is 2,000 feet to the northeast. All other residential structures are located greater than one mile from the site. Golder Associates e inn September 1991 11 -913-2324 2.6 Number of Users Applicant has obtained traffic surveys which are provided in Appendix B to this Application. Applicant does not expect the number of patrons to change from what was established and in Appendix B; i.e., 400 to 500 vehicles per day. 2.7 Employee Requirements and Operation Schedule The Applicant does not expect the staffing levels at the Property to change from the existing level. The present and projected staffing levels are approximately twenty (20) positions which consist of two (2) site supervisors, three (3) gate and record keepers, nine (9) heavy equipment operators, three (3) laborer/spotters and three (3) mechanics. The landfill is presently permitted to operate twenty-four (24) hours per day and seven (7) days a week. However, the normal operation schedule is from 5:00 A.M. to 8:004.M., six days per week and will generally be closed on major legal holidays. 2.8 Water Source Two on-site wells will be used in conjunction with a 10,000 gallon cistern for storage. The wells are approximately 650 feet deep and will provide enough water for use during operation for dust and fire control. 2.9 Access Routes Access to the Property is from Interstate 25, Colorado Highways 52 and 7, and Weld County Road 5. The main gate entrance to the landfill facility is located to the west of the Pratt Property. All incoming vehicles must pass through a gatehouse at the entrance. Golder Associates fr'O' n" September 1991 12 913-2324 2.10 Vehicular Traffic Applicant does not expect the vehicular traffic to change from what has historically been established. A vehicular traffic survey was conducted on July 12, 1989, in order to determine the type of traffic at that time. The survey was conducted between the hours of 3 A.M. and 9 P.M. The survey indicated that the highest traffic volume occurs between the hours of 8:00 A.M. and 4:00_P.M. with peak flows from 12:00 noon to 3:00 P.M. Table 1 summarizes the results of the survey and Appendix B includes the traffic survey results. It also should be noted that the number of cars/pickup trucks normally increases on weekends and the number of commercial hauling trucks decrease on weekends. Golder Associates 0639 September 1991 13 913-2324 TABLE 1 TRAFFIC SURVEY Unloaded Weight: Loaded Weight vehicles Vehicle:.Type Front-Load Collection Truck 32,000 54,000 44 Rear-Load Collection Truck 29,000 54,000 149 Roll-Off Containers 21,000 54,000 34 Transfer Truck 40,000 80,000 67 (Tractor-Trailer) End-Dump Trucks N/A N/A 4 Cars N/A N/A 5 Pick-Up Trucks N/A N/A 52 Miscellaneous' N/A N/A 73 TOTAL 428 NOTES: 1. Miscellaneous vehicles include vans, cars with trailers, etc. 2. Weights are approximate. 3. N/A - indicates zlata is mot available. 2.11 Sewage Facilities Restroom facilities for site personnel are provided at the shop and at the gatehouse. Septic leach fields are located between the shop and office. Golder Associates t,,2:0,t.39 September 1991 14 913-2324 2.12 Fire Protection Burning of waste will not be permitted at the landfill site. Any fires which occur in the waste will be extinguished by excavating, removing the burning refuse and covering it with soil. Additionally, all equipment operators will keep fire extinguishers on their machines to control small fires that do not require excavation and covering. 2.13 Types and Numbers of Animals The Property is fenced at its perimeter and no animals will be associated with the operation of the landfill. 2.14 Waste, Stockpile, or Storage Areas All incoming waste will be immediately unloaded, spread, compacted and covered with soil. The stockpiled soil for daily, intermediate, and final cover for the compacted waste will be stored in the undeveloped portions of the landfill. When the last area (Cell D) is needed for waste disposal, the stockpile area will then be relocated on developed property. 2.15 Storm-Water Management The surface water management plan has been designed totontrol the surface water from the site in such a manner as to minimize the effect of landfill construction and operations on off-site drainage patterns. This includes features to control erosion and attenuate peak flows off of the area of operation. In accordance with CDH regulations, the 24-hour storm with a return period of 100 years has been used as the design storm for all permanent surface water control struc- tures. Temporary surface water controls were designed using the 25-year,24-hour storm. Golder Associates r.=J*''. September 1991 15 913-2324 Fifteen-feet wide grass-lined covered benches in the closure cover will be constructed 40 feet apart vertically and have a three percent longitudinal slope. Four gabion-lined channel downspouts will collect the surface water from the cover benches and direct it to the perimeter channels. The perimeter channels were designed to intercept surface-water runoff before it enters the landfill and collect surface-water runoff from the landfill. An access road channel, located on the landfill closure cover, parallels the access road and collects runoff from the road and from two closure cover benches. All channels are lined with riprap to control erosion. 2.16 Removal and Disposal of Debris, Junk and Other Wastes Compaction of waste immediately upon placement, application of soil cover, and control of the orientation and size of the working face are all effective in keeping blowing litter to a minimum. Portable fencing will be placed around active working areas and other strategic locations and permanent fencing will surround the facility. Any litter which escapes from the working face will be manually retrieved and returned to the landfill by site personnel and, if necessary, temporary labor. All incoming loads will be covered or otherwise be charged double the standard disposal fee. During high winds, the site supervisor will suspend landfill operations, as per CDH regulations,and place daily cover. 2.17 Landscaping Plans and Erosion Control Landscaping around the site includes planting drought-resistant trees and shrubs around the buildings to enhance the aesthetics of the structures and surrounding areas. The primary means of controlling erosion from the final closure cover is the establishment of vegetation as shown in the Design and Operations Plan. Cover benches will intercept surface runoff from the 4H:lV slope, thereby reducing the velocity and theTotentiallor soil erosion. Golder Associates r t)t September 1991 16 913-2324 Erosion potential of the landfill cover was evaluated using the Universal Soil Loss Equation. Calculations for erosion of the landfill indicate that 2.7 tons of soil per acre per year (approximately 1.36 inches in 100 years) will erode. 2.18 Reclamation Procedure The post-closure care period will continue for 15 years after completing the final closure cover of the landfill. The site is expected to remain in a vegetated, undeveloped condition throughout the post-closure period. Any other post-closure use of the site which may be planned or proposed will be designated such that the integrity of the final cover is not disturbed. The final cover topsoil will be revegetated with a grass mixture recommended by the U. S. Soil Conservation Service and with native shrubs (e.g., sage brush and rabbit brush) on ten-foot centers. Groundwater, leachate, and explosive gas concentrations will be monitored on a quarterly basis for the life of the facility and on a semi-annual and annual basis for a 15-year post-closure period. Additional post-closure care activities consist of: (1) inspection and repair of the cover as necessary to correct the effects of settlement, subsidence, surface cracking, and erosion; (2) maintenance and operation of the groundwater monitoring system; and (3) maintenance and operation of the gas management system. 2.19 Construction and Start-Up Schedule Construction of the landfill can begin as soon as February, 1992 with Weld County's approval of this Amended U.S.R. Application and issuance of a Certificate of Designation. Golder Associates r063 September 1991 17 913-2324 3.0 SUPPORTING DOCUMENTS AND STATEMENTS This section provides statements concerning the consistency of the proposed use with the Weld County Comprehensive Plan, the district in which the use is located, and the compatibility of the proposed use with the existing surrounding uses and future uses, as required in Item 3 of the application requirements. 3.1 Need for the Facility Within the Proposed Area of Service The Property which is the subject matter of this Amended USR Application is already designated as a sanitary landfill by SUP 400. The Denver Regional Landfill North, directly across the street from the Property is nearly at capacity and there are 400 to 500 vehicles which visit that site each day. When Denver Regional Landfill North reaches capacity, there will be a need for a landfill in the location of this Property. Further, (I) existing disposal sites are diminishing, (2) waste generation rates are increasing and are predicted to continue with that trend, (3) recovery of materials from the waste stream is not great, and (4) a strong need exists to innovatively and effectively approach waste management. This Amended USR Application addresses the need for a well-suited landfill which exceeds the EPA Subtitle D Regulations. 3.2 Consistency With the Weld County Comprehensive Plan The Weld County Comprehensive Plan consists of various goals and policies to guide existing and future land use planning decisions. The following sections of the Weld County Com- prehensive Plan are relevant: a. Agricultural Goals and Policies; b. Urban Growth Goals and Policies; and, c. Environmental Quality and Natural Resources Goals and Policies. Golder Associates �. Q6t.: September 1991 18 913-2324 3.2.1 Agricultural Goals and Policies The proposed Amended USR site is presently permitted as a landfill under SUP 400. The design has been modified to include vertical expansion and additional protection to the environment beyond the current requirements of the Colorado Health Department. Agricultural Goal 8 of the Weld County Comprehensive Plan is "to develop policies and regulations to permit the conversion of geologically suitable non-prime, agricultural land to solid, liquid and waste disposal sites." The Soil Conservation Service (SCS) indicates that the site is not prime agricultural land. According to the SCS, there are only two soil descriptions located at the site and they are classified as having "severe limitations that reduce the choice of plants..." or "require very careful management" or "that make them generally unsuitable for cultivation." Table 2 contains information regarding the soil names and capability classes of the soils on site. Agricultural Goal 8 is keyed to a position of support for approval of a Use by Special Review Permit for the facility. The soils surrounding the site are shown on the Figure 2, Vicinity Map. TABLE 2 SITE SOILS Soil Number Soil Name Capability Classes` 36 Midway Shingle Complex VIe nonirrigated 67 Ulm Clay Loam IVe Nonirrigated NOTES: 1. All land in Section 29, T. 1 N., R. 68 W. is nonirrigated farmland. The pertinent capability class descriptions are as follows: Class IV soils have very severe limitations that reduce the choice of plants, or that require very careful management, or both. Class VI soils have severe limitations that make them generally unsuitable for cultivation. Golder Associates ✓ 06..9 September 1991 19 913-2324 This application is innovative in that agricultural land will be preserved by the vertical expansion proposed by the Applicant because no additional surface area will be consumed. Agricultural Policy No. 9 indicates: "The County will develop and maintain procedures and guidelines for disposal sites that are operated as a commercial enterprise. This includes, but is not limited to, the disposal of solid, liquid, and wastewater in agricultural zoned districts. "A disposal site's plan should address preserving or minimizing the removal of prime agricultural land. In addition, any future reclamation plans must consider the Comprehensive Plan's Agricultural Goals and Policies. "Access between public roads and the proposed disposal site shall be granted only after consideration is given to the land uses and traffic patterns in the area of development and the specific site. Internal road circulation, off-street parking, acceleration-deceleration lanes, common access collection points, signalization and other traffic improvements shall be required wherever necessary to mitigate traffic impacts caused by the development. "A Municipality's adopted comprehensive plan goals and policies will be considered when the disposal site is determined to be located within a municipality's urban growth boundary area." Regarding Agricultural Policy No. 9, it should be noted that the Property is zoned Agricultural and in 1979 was given a Special Use Permit for a sanitary landfill (SUP 400). No additional agricultural land will be removed from production under this Amended USR Application. Further, regarding access between public roads and the proposed disposal site, the same traffic patterns will be used as have been used for the Denver Regional Landfill South which has been adequate to date. There will not be additional increased traffic and, thus, no need to mitigate additional traffic impacts. The Property has been determined to be in Erie's Comprehensive Plan and Applicant believes that the additional environmental safeguards will make the Property more suitable and acceptable to Erie (by adding the environmental enhancements) than the SUP Golder Associates c�^ � .a ••Qd 1. September 1991 20 913-2324 400. Further, Erie's Comprehensive Plan indicates that the majority of the area surrounding the proposed use will be utilized for non-urban purposes. 3.2.2 Urban Growth Boundary Goals and Policies The Property is located in the Urban Growth Boundaries of the Town of Erie, the Cities of Lafayette, Broomfield and Thornton. With regard to all of the surrounding communities, it is important to remember that the Applicant is already permitted to use the Property as a landfill under SUP 400 and the present Applicant will protect the Health, Safety and Welfare of the surrounding towns by upgrading the Environmental Controls (see Section 2 above). The Town of Erie Comprehensive Plan indicates that the Property which is the subject matter of this Amended USR Application will be used for non-urban purposes. Further, the Town of Erie has annexed the Denver Regional Landfill North which is across Weld County Road 6 from the subject Property and, accordingly, Applicant's use of its land will be compatible with other landfills in the area. Although the Property is within Weld County's Urban Growth Planning Area, it is not within the Comprehensive Plans or Master Plans of the Cities of Lafayette, Broomfield or Thornton. Again, since the Environmental Controls on the Property are essentially being upgraded from SUP 400, the changes should be welcomed by the surrounding municipalities. The County's Urban Growth Goals and Policies require that there be responsible residential land use and development cannot occur without well-planned, adequately-designed and efficiently-operated residential support facilities such as proper and environmentally-sound waste management service. The proposal of Applicant meets such a need. 3.2.3 Environmental Quality and Natural Resources Goals and Policies The "Solid Waste" section of the Environmental Quality and Natural Resources Goals and Policies portion of the Weld County Comprehensive Plan indicates that: Golder Associates �, T��9 Ca<: S3 September 1991 21 913-2324 "An application for a_disposal site will be evaluated in detail regarding the adequacy of: access roads, grades, leachate and drainage control measures, fencing, utilities, volume requirements, site improvements, reclamation plans, and-day-to-day operations including equipment requirements. In additional, compatibility with existing and future land uses of the area must be demonstrated in terms of visual degradation, pollution, traffic, dust, noise, scale, density, topographic form, geology, operating plans and reclamation plans." Accordingly, the following matters should be considered: a. Access Roads Access to the Property is via Colorado Highways 52 and 7 and Weld County Road 5 from Interstate 25. These roads have proven historically adequate while utilizing the Denver Regional Landfill North. Applicant expects that the same traffic patterns will be utilized for the amended USR Application Property (see Section 2.8 above). b. Grades Grades are shown on the Engineering Supplements submitted with this Application. The Engineering Reports indicate that the subject Property is an excellent site for a landfill of the type and nature requested by Applicant. c. Leachate and Drainage Control Measures See Section 2.1 above. The entire composite liner will be covered with a leachate collection system (complete sand drainage layer with laterals and headers) leading to four sumps from which leachate can be removed should any develop. An engineering plan has considered leachate and drainage control measures throughout. d. Fencing The Property's perimeter is completely fenced. e. Utilities As is indicated in Sections 2.7 and 2.10 above, there are utilities to the site including water and septic leach fields. f. Volume Requirements The volume requirements of the site are set forth in Section 2.1 above. Golder Associates cue, r September 1991 22 913-2324 g. Site Improvements There are numerous site improvements to the Property set forth in the attendant materials. h. Reclamation Plans There are numerous reclamation plans to the Property set forth in the attendant materials. i. Day-to-day Operations Including Equipment Requirements See the Design and Operation Plan submitted with this Application. The "Solid Waste" section of the Environmental Quality and Natural Resources portion of the Weld County Comprehensive Plan, at page 75, refers to the Property which is the subject matter of this Amended USR Application. The Property, at the time of writing the Comprehensive Plan, was known as the "Columbine Landfill." The Weld County Comprehensive Plan, at page 75, states the following: "The Columbine Landfill was opened in 1980 as a 160-acre site. In 1982, an additional 34-1/2 acres adjoining the northeast corner of the landfill were added to the site. The facility is located south of Weld County Road 6 and west of Weld County Road 5. The Columbine Landfill currently accepts up to 4,000 cubic yards of waste a day. The remaining capacity at this site is estimated at 12.5 to 25 million cubic yards. Depending on price, competition, operating capacity, and growth rate, the life of the site was estimated at 12 to 20 years in 1987. This site serves an estimated 500,000 in the Denver and Boulder metropolitan areas." From the above reading of the Weld County Comprehensive Plan, the Columbine Landfill was, at the time, estimated up to 25 million cubic yards. This Amended USR Application will not expand what was designated in the Comprehensive Plan to be the capacity of the landfill. In Section 2.1 above, it is estimated that the available capacity for future filling under this Amended USR Application will be approximately 1\7.2 million cubic yards. Golder Associates 639 c*. 0 ad L4... September 1991 23 913-2324 3.3 Consistency With the Intent of the District in Which the Use is Located See Section 3.2.1 above. 3.4 A Statement Explaining What Efforts Have Been Made in the Location Decision for the Proposed Use to Conserve Productive Agricultural Land in the Agricultural-Zoned District As indicated in Section 3.2.1 above, the Property has already been designated as a landfill under SUP 400. No additional agricultural land will be taken from productive use. In addition, the land is not "prime agricultural land." 3.5 Protection of Health, Safety and Welfare of the Inhabitants of the Neighborhood and the County This Amended USR Application is primarily aimed at environmental enhancements as set forth in Section 2.1 above. These environmental enhancements will meet EPA Subtitle D require- ments. Some of the measures taken to protect the health, safety and welfare of the nearby residents are clay liners to contain solid wastes and monitoring programs for groundwater, surface water, methane accumulation and leachate generation. Operational measures to prevent negative impacts on nearby-residents include: ceasing operation during period of high winds, utilizing litter-control fences, an immediate application of soil cover to reduce odors, vectors and litter. 3.6 Compatibility With Surrounding Land Uses The Property which is the subject matter of this Amended USR Application is located on an existing landfill (SUP 400). The surrounding land uses consist of agricultural land on the west and south, the Laidlaw Denver Regional Landfill North located directly to the north and the closed 25-acre landfill to the east. The use of the site for landfill has been established under SUP 400 and is compatible with the existing surrounding land uses. Golder Associates 7CteZn September 1991 24 913-2324 3.7 Compatibility With Future Development See Section 3.2.2 above. 3.8 Overlay Districts The proposed use is located on an existing landfill and is not located within the airport or flood plains overlay district areas. The proposed use is located within the geologic hazard overlay district, which has the potential for ground subsidence from the abandoned Columbine Mine underlying the landfill site. The landfill has been redesigned for the "worst-case" ground subsidence which indicates a maximum subsidence of two feet toward the old coal mine. Therefore, the proposed use as a landfill is an acceptable use. The Laidlaw Landfill, which is adjacent to the proposed site, is located in the same geologic hazard area, and the Town of Erie Comprehensive Plan indicates that soils underlying the Laidlaw Landfill are suitable for landfill development. 3.9 Water Supply As indicated previously, an existing well and a new 650-ft. well will provide the necessary water for the proposed use. In addition, a 10,000 gallon cistern is used for storage. A copy of the well permit is included in Appendix C. 3.10 Property Interests Photocopies of the Deeds indicating Laidlaw's interest in the proposed properties are presented in Appendix D. Golder Associates c+7-0,rl • September 1991 25 913-2324 3.11 Noise Report All operations at the site currently generate less than the light industrial limit of 70 decibels of noise 25 feet from the property line as required by C.R.S., Section 25-12-101, and no foreseeable change is expected. 3.12 Soil Report The SCS soil survey does not indicate any moderate or severe soil limitations for landfill activity at the site. The soils at the site are quite suitable for landfilling. Soils are generally silty clays with a trace to some sand and are of low plasticity; soil thickness ranges from about 1.5 to 17 feet. There is very little perennial saturation of the soils. The occurrence of water in the soils appears to be controlled by increased infiltration at areas of the surface water concentration and by the presence of relatively thick soil deposits. The hydraulic conductivity of the natural soils is generally low, from 1 x 10-6 to 1 x 10-5 cm/sec. 3.13 Adjacent Property Owners r Appendix E presents a list of property owners and addresses within 500 feet of the proposed rlandfill. This information was compiled from records of the Weld County Assessor. A signed affidavit indicating that the list was compiled within 30 days of the Application submission date is also included in Appendix E. r3.14 Mineral Owners and Lessees A certified list of names and addresses of mineral owners and lessees of minerals on or under the proposed site is provided in Appendix F. This list was compiled from records of the Weld County Clerk and Recorder within 30 days of this Application submission date. r Golder Associates x {� 7O23 3 V"- 1.ils. COLORA De*STAf ST-Aft-HIGH / 52 _ _ _ -'�, C�_ _ ' j: , %. r • .mot...•:`'' jIi '�.'� f. r .s� 1 s,S..l'r. S. .. 4 A rte: f 1,4,,, I IIJ -- ! • )o • • • s. 1 J.. b - r ....... �,. K • r i. ,',;AA-1.J_ .1 •^.14 t TA..14.5,fr.„... .L.:2; .,.1.0. - ifIT. .:.Praia ''1 Ill ., ,�,1,s" - l4.,• 1- _ _ •i Iii jIi f. ''• _ ` _. {' I ..��'.�•._ +• i 'l ...4..,,:,'.+�`ors€ . ' • 16 4.11 qtyy'' ' 7 15 34 t w •f is 3. r • N.. •., a , • s3 : :- 1;> •' 4 ea • �...i.�,• . -i , ...,..:.,.',u :e. .. ., I, rr�• 7 f .. �,4 _.�.. #. 1. �f` .,,, 27 "„ii_,.( ,� 26 sly *' "( �` N II¢. ,. . . l - l' , ; ...'s.-J i- 4" it s• l'-'-' •• r ]r 1. , ru. p %, 1 y \ 1 f • j q• .,.::- 1 .i .�r..,... ........‘,4. _ „„. L,,eOLOIDI O'O STATE H! 4 . • t R. 69 W. R. 68 W. �, - - REFERENCE: USGS FREDERICK, COW. QUADRANGLE, 1979 USGS ERIE, COLO. QUADRANGLE. 1979 9 Golder Associates Inc_ TITLE Denver. Colorado SITE LOCATION AND VIC I NITY CUENT/PR01ECf DENVER REGIONAL LANDFILL WELD COUNTY, COLORADO DATE SEPT 1991 SCALE 1•=1000' JON No 913-21924.009 BOL JCNtCKto SSL IDRAWN REVIEWto DLO PILE OWL NO. 3 APPENDIX A ORIGINAL SPECIAL USE PERMIT AND CERTIFICATE OF DESIGNATION I 1 1 I September 1991 913-2324 Golder Associates r^OS09 SENT BY:HQLLC -C , & HCIRT ; 6-11-91 Ii:16QM 1 3032958457-, 3033536712;# I ,Jl, MI Jd4L J0a1" In"4 I. Illunaw IMUM •I SENT BY. XEROX To;,eopier 1017;• 9- 4-91 ;10,;,OL*.yl 9036199432» 3032958318 ;6 2 II I • R6:, APPROVAL OF CERTIFICATE OF DtSIGNATION FOR COLORADO LANDFILL, INC, • ERIE SITE WHEREAS, the Board of County Commissioners of Weld County, Colorado, pursuant to Colorado, etatute and the Weld County Home Rule Charter, is vested with the authority ,of administering the affairs of weld County, Colorado; and , WHEREAS, on the 4th day of Hay, 1903 , a public hearing was held in the Chambers of the Board of County Commissioners of weld County, colorado for the purpose of considering whether or not to grant a Certificate of Designation to Colorado Landfill, Inc. for a solid waste diepbeal sits and facility to be located on the following described property; A tract of land situated in the feat It of the NE1 section 29, Township 1 North, Range 66 west of the 6th P.H, in weld County, Colorado, • being more particularly described as follows; Commsnatag at the Northeast Corner of said Section 29 and considerinq the North line of said Section, 29 to bear North 19'17 '31" West with all bearings herein relative thereto; .Thenda North 19'37131' west, a . distance of 144. 00 feet tb the True Point • of Beginning; Thence South 00'04 '55" West, a distance of • 1'061; 55 feet, Thence South 69'23'05"' West, a distance of 1252.00 feet; Thence North 00'04'55" rast,' a distance of 1506.00 feet, • Thence South 11437'11" Bast{ a distance of 1172.73 feet to the True Point of Beginning, said tract of land containing 34. 5 acres, more or 1esi, SXCLPT, beginning at the Northeast Corner of said Section 21, Thence 500 teat west along the North line of said Section 29 to the True Point of Beginning; South 700 feet; Thence West 435,6 feet; Thence North 200 feet; Thence Sant 435, 6 feet to the True Point of Beginning; said excepted tract containing 2 sores, more or lees, • WHERSAI, Section 30-20-104, CIO 1973, requires the $osrd of county commissioners to take into •crnllnt ea -t stn factare% and isTsocari wunnns, the Board has taken into account such factors and SENT BY:H0LLAND & MART t 6-11-91 11t17AM : 3032' •4S9i - .....' SIN' tlY7 XEROX T111COp0e. /0171 6- 4-61 02914OAi1 I .. 3e33s3571z: 2 5 Page 3 - 6O3e776/90!+ 3032056370 ;s J AEI CERTIFICATE OF DESIGNATION - COLORADO LANDFILL, INC. ' . a) The solid wants disposal site and facility will have no substantial detrimental effect on the surrounding property. b) Viet the solid waste disposal sits and facility will be convenient and acesaeibls to potential users, 0) That the applicant has the ability to comply with the health standards and eperatin pro- cedures required under Section 30-20-101. et tionagas prsicribed by the State 1973 nd the r as aDepartnd tment of Reelth. d) That the Board has considered the recommends, Lions by the Weld County Department of Health. a) That the proposed use will comply with the • Weld County Comprehensive Plan, ,, NOW, THEREFORE, SE IT RESOLVED by the Board of County Com- missioners of Weld County, Colorado that the Certificate of Desig- nation for Colorado Landfill, Inc. for a solid waste disposal site and facility located on the hereinabove described real pro• party be, and hereby is, granted, The above and foregoing Resolution wan, on motion duly made 1 and seconded, adopted by the following vote on the lih day of May, •A.0„ III). ATT3STt t 1/47 44. BOARD OF COUNTY COMxISSIONBRS a WILD COUNTY, COLORADO weld County Clerk and Recorder EXCDSED D TE OP IGGNzxo tavE ,an ark to the eon au x Carlson, Chairman Sys Duty Y T. ar , co- am • APPROVED AS TO FORMt Y;8 sa...ietries �� one . flantner bouulty eo ge2 AYE Orman itt 6eeltn equ ne ere...e"�. (JtYT) �a+r� sama . DAT FILE, xay 1, 1,12 ._. ../._ ua.: vS EP — 4 — •9 1 LIED : 49 SHA DF_ DO 'r' LE f: P - X32 .1 ARD F WHTY COMA 510N eS LT :L�)i THIS IS TO CERTIri THAT THE BOARD OF COUNTY CU4tISSIONER ELD Cp1MTT, COLORADO DOES HEREBY CONFIRM AND ADOPT THIS SPECJIAL USE PEWIT AND Ofvfl,pp (� ;STAr04RD5 . ' S a i AS SHOWN AND DESCRIBED HEREON THIS L" OAY of '—`�� h .� 1.0 -n . • RD !'''ee��...',�t.:I( LL BOARD OF COUNTfiryylDNER3 t ATTEST: COUNTY CLERK -J\Jr �\ • l , DY% DEPUTY s t RECORDED BY: \r' :::::::::11: OUNTY RECORDER 5TE: ' h PROPERTY NER�S ADP ROYAL „ . � 1. 1 THE Ut1�ERSIGNEO MAJOR PROPERTY OWHER(s) WITHIN THIS SPECIAL USE PEAXIT DO HEREBY OAY OFpr �E O TXE DEVELOPMENTSTANDARDSADESCRIBEDHEREONTHiS, A.D., 1979, e\\Heil 5UPV°W' ;.(\i:::;,....H ------• . . DEYELOPMCNT STANDaFDs_ appropriate equipment and structures may be permitted where 1: The permitted use on the hereon described Special Use Permit area shall be permitted insanitary landfill,y idettal and cep op Section clearly incidental and accessory Zoning to the landfill use as well as uses p 3.311 of the Weld County Zoning Resolution.and approved by qualified geotechnl- t of 2,• 'calSelection soathat^ all liner materials be achieved. .1,_.........aei--' County, State, and Federal Health Standards and Regulations and any other applicable j 3. All phases of the landfill facilities and operations shall conform with all applicable rules and regulations of government bodies raving auiiumipeimn On the D remises. A. All phases of the operation must conform CO mailmen permissible noise levels as stated in 25.12-103, CAS, 1973. B. The applicant will siod permit r tive C. The applicant Shall bberresponsi for obtainingg to the nprovisions.ofo the uC dust. an Colorado Air Pollution Control Commission's Regulation No. 2. other bodies of water. or D. There shall be no discharge of wastes Into any streams, nation System Permi adjact l imi- t et from the Systems without Colorado Departmertt of a Health��t • on Discharges E. All phases of the operation must conform to 30-20.101 et. seq,,CRS, 1973 for solid waste disposal sites and facilities. t lighting provided for security and night operation on the site ih ll•be designed so t a t . the lighting will not adversely affect surrounding prccerty owners. All S. accessesAll shall have inproval of accordancenwithe l the d n recommendations9and/ore equirements• of the Weld County Engineering Department, 6, All design and construction shall conform to applicable local,'state and national build- ing codes, 7. All structures shall comply with the minimum setback requirements as defined in Section 3.14 of the Weld County Zoning Resolution, uch a B. il erosion,i fugitives dust ands growth of noxiousnweeds.shall be maintaied ins The sites shall dbea maintai t ned to such a manner as to present a neat and well kept appearance. q, The site shall be appropriately fenced so as to control scattering ring of wind blown debris and confine ell solid wastes discharg to ed the site, in addition to debris stock and security fencing may be r rto • ignee to. Surface drainage diverted from ric patterns roval by 1 the9Cotorado Water area Conservation shall be s Ebard)• for a 100 year storm frequency (design approval il. Surface restoration shall be done concurrent with landfill ac tt vibes where practicable. ( Restoration lobetdo done eoin Conservationaccordance with SoiSoil Conservation Service recommendations ( or with approval hereon and governed 1. . TDee lopminl St¢ dardsT shall ae vmandd tl applicable Me d County Regulations Dy the Anv ma' - tevelopdyi Standards stated above sa and ell e alpthe atennt Planning t rttppl d¢ {aNpn from the plans and/or•DevetoDment Standards,es,shown or state a eve SAall require the approval of an amendment tb.the Special Use Permit by plans and/or n Commission and the Board of County Commissioners before Such changes from the plans and/ • Development Standards shell be filed in the office of the.Depertment Of Planning Services. Or Development Standards shall be permitted. 'Any other change}.tram the t t. SEP — 4 — S 1 wED 1 _ - 4a S+1 .-t DE . DJ 'r'1 = -, i_ 2.-. -. - . �- _ _ 0.00 1/001 'p' . , . • . . ,.i .. .... ,� .,:L•.. JJJj�{, r"' ' .'� •� IA 4,? ' '1104^;t:, .k•1'..^.Sa 11N•.. /rf. t t •1%♦ • ,Ii• • ' , • . , . : • . is 1. \•.� trio' '. :. _.I /I,- • .: , ti 1! L ;r I , ./• 1'-'•� ` ,. I.. •• i I' li, .,..,:.-:',•:,.. 7(-. - •\ 1•. L. `,, `�•! . i r1 • 1 r 1 / 1 i `1... . ♦ +'w: , r � - 1'• 1: . / wI.{ \ > �• + i ' :.r 1�•'_` f sd' •. fir �`. �• ; 2 ' �_� ;�': y-•�` �p _ _ •'n , :, w''� > CCU a\ /LG�f • • ( •i. rw ( .• - +r/ 11 .i.•_ , • �, 1 ', .`l1 0• '.L`"`, \\ -_\" a" :� =' , i�' ' wi'1 '.i_ '.28' c. elf ii Cst� 1 s p ilk 's" ,j..� � C t, (li �i� 200' �/` r \ ' 1 • 9S , \'` .i'•_ ,' ```'� + �- ✓l�1'_ •�� • _ / <.I 00 t� J 44. , \ 1 r _ rS• ..,.. . 1 [/-' :, .,-....,,..t�•'-.3 ., -- • - . ( . I 11 - �� _ ' .r Win'"_ l-`..�„ (_•t`. „C••••••---•••••••• � � i Y , f ci t _ J _• I1Ny iti ( (.•• ♦ ♦••_i 1 .•SJt .er 1 �•• ••• \� Yi, N • .a.. _... .... r 1 ..,..... AD 1 • °I-6"M Lufetttt INc'}`.J'- 1 1 L. A ', ! V �^ -; C - :A.A..' • acantt- Irumi.w/ , - y (� 'v P '�Y . ':.'. ..°k^V ..3 tl'• - : , , r . w 1' •. -.RCQT F',e".•22aO' . .: t 4•,./IYf • ' 1 I 1 APPENDIX B ' TRAFFIC SURVEY r i i I a September 1991 913-2324 Golder Associates • ©aillgffaf LAIDLAW WASTE SYSTEMS INC. DENVER REGIONALAANDFI L July 14, 1189 Daniel R. Horst 2240 -Weld Co. Rd. 15 Erie, al 80516 Dear Mr. Horst: As per your request, we ran a traffic study on the Denver Regional Landfill on July 12, 1989. A total of 428 vehicles came into our site between the hours of 3 :00 am and 9:00 pm. 4e consider this amount of traffic to be average for a Monday through Friday work- week . When we are open on Saturday from 3 :00 am to 6 :00 pm, there woul4 be approximately one third ( 140 ) large waste trucks coming into the landfill and approximately twice the amount of oars & pickups (80 - 100) , from the private sector. The direction/routes of the large waste trucks are as follows : From Denver, -Colo. using I-25 to State Hiway #7 T-0 Weld County Road #5 : 76% Thru Lafayette,Ctl0. •using State Hiway #7 To Weld Co. Rd. #5: 16% Thru Erie, Cola . using Road #8 To Weld Co. Rd. #5 : Less than 1% From I-25 using Road #8 To Weld Co , Rd. #5: 2% Trom Longmont using State Hiway #52 To Weld Co . Rd. #5 : 3% From 8erthoud,Colo. using State Hiway #7 To Weld Co. Rd. #5 : 2% Please see attached sheet for a breakdown of what ty-pe and amount of these vehicles come to our landfill . As far as the rest of the traffic, ( IE: cars , pickups , trailers ) the routes they use are hard to ascertain. 1441 WELD COUNTY ROAD 6. P.O. BOX 320. ERIE COLORADO 80316(303) 673.9431 c''lc 4 • ©affffffQg • Daniel R_ PJul 14,age 19339 Horst We are _quite sure these vehicles are from the fnllowirg are-as : Narthglenn Dacono Broomfield Frederic-k Westminster Brighton Louisville Ni-+ot Lafayette Erie It me can be of any further assist-ance.to you, please do not hesitate to call . Sincerely , Ric-k Hoffman Division Manager Enclosure ii • enn .... r... TIMM SWOT TOTE the !SORT-LOAD 17.O. L0AD ROLL-Ott WWA.SWI = ItlID-0@RS CAM ncr.0 S nrsr L.4 a I. J.... 7 J.:.. ate. I I — 0- I - 0' -0 - -0- -0- ' 3 I ...4 1 I 7 I -o- -0- -o - -o - 9 J..4 J..4 �o - -o - I Iy �... - 0' 8 3 - 0- �� 4 a I 3 -o - -0 - 3 a 15 I.... CD Li y -1-I _I 16 -o- -0 a a \ ;; e.... 3b c. 5 10 5 5 -0 - o - a I 9.... I a 36 ito a.. 9 9 4 5 - O - -0 - it:" 3 I S a -6 -0 - - 0 - 2 3 34 t. u... tt... t. S Ia 6 • 3 - 0 - -A - .5 5 36 cc. -i 12 3 77 -0 - -0 - q k 'i to 1p.4 .4..' 19 I `i -0 - I 5 3 1-/-3 t. :.... 2p.m. -o - I a q 9S t. y.. as I 6 Jp.4 Jp.o.to 3C 3 b -3 H -0 - I 5 `p'`t. a 3 -0 - 3 - 0 - -0 - H H I ' Spat. 6 -0 - 5 a I a 1 1' t. -•0 - Cro;; .. I - o • 5 - p - - o - I a t. -o - tp.4 to -0 - -0 - - 0 - 3 a I 3 I II Spam. Sp... - 3 -O L -0 . _ I - - - to 170C int_ ■I TOMS '4y I y_9___ 39 b1 LI 5 5 ; '73 LI APPENDIX C WELL PERMIT September 1991 913-2324 Golder Associates r--,.x.,`,79 HULL Ur ! FIE n - - - - -GWS-25 COLORADO DIVISION OF WATER RESOURCES 818 Centennial Bldg.. 131: ;man St.. Denver, Colorado 80203 (303) 866-3581 Stop 4 )� LIC RECEIVED WELL PERMIT NUMBER 038450 F -- APPLICANT 1 .1R 1 ') j 31 DIV. 1 CNTY. 62 WD 6 DES. BASIN MD DENVE 1'LL#534 APPROVED WELL LOCATION COUNTY WELD NW LAIDLAW WASTE SYSTEMS 1/4 NE 1/4 Section 29 _ P O BOX 320 Twp 1 N , Range 68 W _S_ P.M. ERIE, CO 80516 DISTANCES FROM SECTION LINES 60 Ft. from North Section Line 2912 Ft. from West Section Line PERMIT TO CONSTRUCT A WELL ISSUANCE OF THIS PERMIT DOES NOT CONFER A WATER RIGHT CONDII1ONS OF APPROVAL 1) This well shall be used in such a way as to cause no material injury to existing water rights. The issuance of the permit does not assure the applicant that no injury will occur to another vested water right or preclude another owner of a vested water right from seeking relief in a civil court action. ur11� 2) Approved pursuant to CRS 37-9O-137(4) and the findings of the State Engineer dated Arr.L. f/79y. 3) The allowed average annual amount of ground water to be withdrawn is 44.1 acre-feet. 4) The maximum pumping rate shall not exceed 30 GPM. 5) Production is limited to the Laramie Fox Hills aquifer which is located 325 feet below land surface and extends to a depth of 710 feet. Plain casing must be installed and sealed to prevent the withdrawal of ground water from other aquifers and the movement of ground water between aquifers. 6) This well shall be constructed not more than 200 feet from the location specified on this permit. 7) The entire length of the hole shall be geophysically logged as required by the Statewide Nontributary Ground Water Rules prior to installing casing. 8) A totalizing flow meter must be installed on the well and maintained in good working order. Permanent records of all diversions must be maintained by the well owner (recorded at least annually) and submitted to the Division Engineer upon request. 9) The owner shall mark the well in a conspicuous place with well permit number(s), name of the aquifer, and court case number(s) as appropriate. He shall take necessary means and precautions to preserve these markings. 10) Pursuant to CRS 37-90-137(9)(b) and the Denver Basin Rules, no more than 98% of the nontributary ground water withdrawn annually shall be consumed and the well owner shall demonstrate to the reasonable satisfaction of the State Engineer that no more than 98% of the water withdrawn will be consumed. 3/7M OWNER'S COPY APPROVED: �Q � / , Q JS !7°r /vk 1-t Staten MAR 121991 By ; Receipt No. 0321357 DATE ISSUED EXPIRATION DATE t..- - �..s FINDINGS OF THE STATE ENGINEER IN THE MATTER OF AN APPLICATION FOR A PERMIT TO CONSTRUCT A WELL IN WATER DIVISION NO. 1 , WELD COUNTY, COLORADO RECEIVED APPLICANT : LAIDLAW WASTE SYSTEMS, INC. f]:\R AQUIFER : LARAMIE-FOX HILLS PERMIT NO. : 321-15.O- FDENVE 'T ILL#534 In compliance with C.R.S. 37-90-137(1) and the Statewide Nontributary Ground Water Rules, Laidlaw Waste Systems, Inc. , P.O. Box 320, Erie, Colorado 80516, (hereinafter "applicant") submitted an application for a permit to construct a well . Based on information provided by the applicant and records of the Division of Water Resources, the State Engineer finds as follows: I . The application was received complete by the State Engineer on January 15, 1991. 2. The applicant proposes to construct the well in the NW1/4 of the NE1/4 of Section 29, Township 1 North, Range 68 West, 6th Principal Meridian. 3. The proposed well is located outside the boundaries of a designated ground water basin. 4. The applicant proposes to apply the water withdrawn from the well to the following beneficial uses: Commercial . 5. The proposed maximum pumping rate of the well is 30 gallons per minute, and the requested average annual amount of ground water to be withdrawn is 48.4 acre-feet. 6. The applicant is the owner of the land on which the well will be constructed. 7. The proposed well would withdraw ground water from the Laramie-Fox Hills Aquifer (hereinafter "aquifer") , which, according to the Denver Basin Rules is located 325 feet to 710 feet below land surface at the location of the proposed well . 8. The location of the proposed well is less than 600 feet from Permit No. 38'1S1 — F completed in the Laramie-Fox Hills Aquifer. An affidavit signed by the owner of the existing well specifically waiving any objection to the issuance of this well permit is on file with this office. 9. According to a sworn statement, the applicant owns, or has consent to with- draw ground water underlying 150.5 acres of land as further described in said statement, which is attached hereto as Exhibit A. 10. Withdrawal of ground water from the aquifer underlying the land claimed by the applicant will not, within one hundred years, deplete the flow of a natural stream at an annual rate greater than one-tenth of one percent of the annual rate of withdrawal and therefore the ground water is nontribu- tary ground water as defined in C.R.S. 37-90-103(10.5) . U Applicant: Laidlaw " ster Systems, -Inc. Page 2 Aquifer: Laramie-, Hills ERE:UEIVED Permit No. : SBL4So —F [11,R i , ji DENVE "rci' #534 11 . In considering whether the requested permit shall be approved, the provi - sions of C.R.S. 37-90-137(4) shall apply and the withdrawals shall be allowed on the basis of an aquifer life of 100 years, C.R.S. 37-90-137(4) (b) (I) . 12. The quantity of water in the aquifer, exclusive of artificial recharge, underlying the 150.5 acres of land described in Exhibit A is 4,597 acre- feet. This determination was based on the following as specified in the Denver Basin Rules: a. The average specific yield of the saturated aquifer materials under- lying the land under consideration is 15 percent. b. The average thickness of the saturated aquifer materials underlying the land under consideration is 204 feet. 13. A review of the records in the State Engineer's office has disclosed that there are existing wells or other water rights withdrawing ground water from the aquifer underlying the land claimed by the applicant. The well permit numbers, rates of withdrawal , and other relevant data concerning such rights are set forth in the attached Exhibit B. To prevent material injury to such vested water rights, the quantity of water underlying the land claimed by the applicant which is considered available for withdrawal has been reduced to 4407 acre-feet. This reduction was based on a calcu- lation of the area necessary to provide a quantity of water underlying such lands as would be sufficient for the persons entitled to withdraw water under existing rights to withdraw the average annual amount of water from the aquifer for the minimum useful life of the aquifer (100 years) . 14. An application for underground water rights for the proposed well is not pending in the Division 1 Water Court. Based on the above, the State Engineer finds that there is water available for withdrawal by the proposed well and no material injury to vested water rights would result from the issuance of the requested permit subject to the following conditions: a. The allowed average annual amount of water to be withdrawn from the aquifer by the well shall not exceed 44.1 acre-feet (the quantity of water is considered available divided by 100 year aquifer life) . b. The well shall be constructed no more than 200 feet from the location specified on the permit application. c. The applicant shall submit geophysical and lithologic logs after the construction of the well . The geophysical logs shall be obtained from the holes before the casings are installed. d. The maximum pumping rate of the well shall not exceed 30 gallons per minute. epn-nenn Applicant: Laidlaw v ter Systems, Inc. Rage 3 Aquifer: Laramie-Lx -Hills ,{ 1 31 Permit No. : 3845C)—F OENVE e. A totalizing flow meter must be installed on the well and maintained in good working order. Permanent records of all diversions must be main- tained by the well owner (recorded at least annually) and submitted to the Division Engineer upon request. f. Production is limited to the Laramie-Fox Hills Aquifer. The well must be constructed with plain, non-perforated casing properly grouted so as to prevent intermingling of water between aquifers. g. The owner shall mark the well in a conspicuous place with appropriate well permit numbers, name of the aquifer, and court case numbers. He -shall take necessary means and precautions to preserve these markings. arit Dated this c) day of ,% )�Cu�L. , 19 ris A. Danielson Sta e ngineer By: u-t F� %(9 —)-(C444" Bruce DeBrine Water Resources Engineer Ground Water Section Prepared by: JTS -6102I/Form 0546(1 ) erifir e 1 IS-Rev 76 COLORADO DIVISION OF WATER RESOURC-ES 818 Centen Bldg., 1313 ShermanSL.Denver, Colorado '.03 PERMIT APPLICATION FORM_ , ,plication must L. complete where (X) APERMIT TO_USE GROUND WATER applicable. Type or (X) APERMIT TO-CONSTRUCT A WELL ( ant in BLACK FOR: IX) A PERMIT TO INSTALL A PUMP I K.No overstrikes of -erasures unless ( )REPLACEMENT FOR NO. initialed. ( )OTHER WATER COURT CASE NO. (1) APPLICANT - mailing address FOR OFFICE USE ONLY: DO NOT WRITE IN THIS COLUMN t IME Saidlaw Waste Systems, Inc. Receipt No. STREET -P.O. Box 320 Basin Dist. c rY. Erie Colorado S0516 (State) (Zip) CONDITIONS OF APPROVAL (303) 673-9431 1fPHONE NO. This well shall be used in such a way as to cause no material injury to existing water rights. The (2) LOCATION OF PROPOSED WELL issuance of the permit does not assure the applicant that no injury will occur to another vested water right or preclude another owner of a vested water Weld ( unty right from seeking relief in a civil court action. NW ''h of the NE Y.,Section Z 9 p 1 N Rng 68 W 6th p.m. IN.S) (EMI ( 1 WATER USE AND WELL DATA Proposed maximum pumping rate (gpm) -30 F :rage annual amount of ground water 48 . 4 to be appropriated (acre-feet): ( -tuber of acres to be irrigated: 10 Proposed total depth (feet): 700 7 uifer ground water is to be obtained from: • Laramie-Fox Hills Shop Well ( rner's well designation GROUND WATER TO BE USED FOR: ( 1 HOUSEHOLD USE ONLY • no irrigation (0) ( ) DOMESTIC (1) ( ) INDUSTRIAL (5) ( _LIVESTOCK (2) ( ) IRRIGATION (6) • (JQ COMMERCIAL (4) ( ) MUNICIPAL (8) ( I OTHER (9) APPLICATION APPROVED DETAIL THE USE ON BACK IN (11) PERMIT NUMBER ) DRILLER DATE ISSUED r'-me Licensed EXPIRATION DATE ,eet ,.•ty (STATE ENGINEER) (State) (Zip) t'+'... L:•sf BY care .an Telephone No. tic. No. ID. COUNTY STATE OF COLORADO 3Z'4 3-F OFFICE OF THE STATE INGINE£R DIVISION OF WATER -RESOURCES NONT-RIBUTARY GROUND WATER LANDOWNERSHIP STATEMENT I (We) _ Rick S. -Hoffman for Laidlaw Waste Systems, Inc. (Name) cl-aim and say that I (we) am (are) the owner(s) of the following described property consisting of 150.5 acres in the County of Weld , State of Colorado: M (INSERT PROPERTY LEGAL DESCRIPTION) CJl 4J A parcel consisting of the NE 1/4 of NW 1/4 plus the NW 1/4 of a the NE 1/4, Section 29, T1N, R68W, 6th P.M. ; excepting a triangular area in the SW corner of the parcel 570 feet long to the north and 340 feet long to the east from the SW corner (2 . 2 acres more or less) , and excepting a second triangular area in the SE corner of the parcel 740 feet long to the north and 855 feet long to the west from the SE corner (7.3 acres more or less) and, that the _ground water sought to be withdrawn from the Larami-e-Fox Hills Aquifer underlying the above-described land has not been conveyed or -reserved to another, nor has consent been given to its withdrawal by another. • Further, I (we) claim and say that I (we) have read the statements made herein; know the contents hereof; and that the same are true to my (our) -own knowledge. Duns./0t( Al' gnature) (Date) (Signature) (Date) INSTRUCTIONS Please type or -print neatly in black ink. This form may be reproduced by photocopy or work processing means. See additional instructions on back. • 1313 Sherman Street 8th Floor Denver Colorado 80203 (303) 866-3581 FIGURE 1 WELL LOCATIONS EXIS11NT WELL PROPOSED WELL vr- 9 / i t1--_I525, • I .lie Mine iu• L___._) _tr..-- C El Q. ( .------ 7(.\----\ K. ES 0_0\\. N O cn C • ..--. Zyn di..8____ff.x\....___.-\_ /A. „. a U O N N a Ai i SCALE 1:12,000 0 \ a SECTION 29, T1N, R68W, 6th P.M. rcc-•s RECEIVED EXHIBIT B H R i J1 3$46-0-F DENVE `"'��r _ #534. APPLICANT: LATDLAW WASTE SYSTEMS, INC. AQUIFER: LARAMIE-FOX HILLS WELL LOCATION NUMBER 1/4 1/4 SEC TWP RN6 AF ST SY RADIUS AREA 83CW094 NW NE 2'9 1N -68W 1 .9 N/A N/A N/A N/A (32027-F) WELL NUMBER = WELL PERMIT NUMBER DR WATER O0URT CASE AND -WELL NUMBER AF = THE ANNUAL APPROPRIATION OF THE WELL IN ACRE-FEET ST = THICKNESS OF THE SATURATED AQUIFER MATERIAL AT THE -WELL LOCATION IN FEET SY = SPECIFIC YIELD OF THE SATURATED AQUIFER MATERIAL AT THE WELL LOCATION AS A PERCENT RADIUS = IS THE RADIOS OF T+IE CYLINDER OF APPROPRIATION IN FEET AREA = THE AREA OF THE APPLICANTS' LAND THAT IS OVERLAPPED BY THE CYLINDER OF APPROPRIATION IN ACRES. 0680I e 7Qe:. GWS-25 COLORADO DIVIS'ON OF WATER RESOURCES 818 Centennial Bldg.. 131, an St.. Denver, Colorado 80203 (303) 866-3581 OFFrcc /dalLIC RECEIVED WELL PERMIT NUMBER 038451 .APPLICANT MAR 1 ; 'l,;jl DIV. 1 CNTY. 62 WD 6 DES. BASIN MD DENVE- • MTJPLL#534 APPROVED WELL LOCATION COUNTY WELD LAIDLAW WASTE SYSTEMS INC NE 114 1/4 Section 29 -ID O BOX 320 Twp1 N , Range-68 W S P.M. ERIE, CD 8_051-6 `i DISTANC-ESfRDM SECTION LINES {®(ni �1 DV 63 Ft. from -North Section tine q�`156! Ei��31 t 2362 Ft. from West Section Line PERMIT TO USE A EXISTING WELL ISSUANCE OF THIS'PERMIT DOES NOTCONFER A WATER RIGHT CONDMONS OF APPROVAL 1) This wellshall be_used in such a way-as to cause no material injury to existing water rights. The issuance of the permit does not assure the applicant that no injury will occur to another vested water Tight or preclude another owner-of a vested water right from seeking relief in civil court action. 2) Approved pursuant to CRS S7-90-137(4) and the findings of the State Engineer dated July 22, 1987 for the expanded use of an existing well, permit no. 114405. 3) The allowed-average annual amount of ground water tome withdrawn is 1.9 acre-feet. 4) The maximum-pumping rate shall not Exceed 15 GPM. 5) Production is limited to the Laramie Fox Hills aquifer which is located 400 feet below land surface and extends to a depth of 6190 feet. 6) A totalizing flow-meter must be installed on the well and-maintained in good working order. Permanent records of all diversions must be maintained by the well owner (recorded at least annually) and submitted to the Division Engineer upon request. 7) The owner shall mark the well in a conspicuous place with well permit number(s), name of the aquifer, and court case number(s) as appropriate. He shall take necessary means and precautions to preserve these markings. 8) Pursuant to ORS 37-90-137(9)(b) and the Denver Basin Rules, no more thana8% of the nontributary ground water withdrawn annually-shall be consumed and the well ownershall demonstrate to the reasonable satisfaction of the State Engineer that no more than 98% of the water withdrawn will be consumed. J75 Ticil -APPROVED: a - /�/ �� JS {,ILt - • C `� 1-.J. Stele Engin r q By Receipt No. D3221361 DATE ISSUED MAR 1 2 199) EXPIRATION DAT .A 4 WRJ-5.Rev. 76 CO, ,nADO DIVISION OF WATER RESOU �S 818 C-entenniaL8ldg-, 1313 Sherman St.,Denver,Colorado 80203 PERMIT APPLICATION FORM Application must be complete where ( ) A PERMIT TO USE GROUND WATER applicable. Type or ( ) A PERMIT TO CONSTRUCT-A WELL print in BLACK FOR: ( ) A PERMIT TO INSTALL A PUMP INK.No overstrikes or erasures _unless I I REPLACEMENT FOR Nn initialed. (X) OTHER Reinstate Permit NO. 32027-F WATER COURT EASE NO. (1) APPLICANT - mailing address FOR OFFICE USE ONLY: DO NOT WRITE IN THIS COLUMN NAME Laidlaw Waste Systems, Inc. Receipt No. STREET B.O. -BOX 320 Basin Dist. CITY Erie Colorado 80516 (State) (Zip) CONDITIONS OF APPROVAL TELEPHONE NO. (303) 673—_9431 This well shall be _used in such a way as to cause no material injury to existing water rights- The (2) LOCATION OF PROPOSED WELL issuance of the permit does notassure the applic-ant that no injury will occur to another vested water right or preclude another owner of a vested water County Wald right from seekingTelief in a civil 'court action. NE of the NW V., Section 2-9 Twp. -2- 11 ,T(ng. 68 W 6th P.M. LN,SI LE.WI (3) WATER USE AND WELL DATA Proposed maximumidumping rate (gpm) -15 Average annual amount of ground water 1. 9 to be appropriated (acre-feet): Number-of acres to be irrigated: lass than 2 -acre Proposed total-depth (feet): 6330 Aquifer ground water is to be obtained from: Laramie-FoxHills Owner's well designation Office Well GROUND WATERTO BE USED FOR: I HOUSEHOLD USE ONLY - no irrigation (0) (>4.1 DOMESTIC (1) ( ) INDUSTRIAL (5) 1 I LIVESTOCK (2) ( ) IRRIGATION (6) IX) COMMERCIAL (4) ( ) MUNICIPAL (8) I OTHER (9) APPLICATION APPROVED DETAIL THE USE ON BACK IN (11) PERMIT NUMBER (4) DRILLER DATE ISSUED Name Existing EXPIRATION DATE Street _ City (STATE ENGINEER) a., (State) (Zip) ,r >atin BY Telephone No. _ iic. No. ____ FIGURE 1 WELL LOCATION EXISTING WELL Vr '8O /� 9 _ r _ 1.1===1525/ 51�c gill 0 ( I -- .'ne Min- - \ � � o � _... cm\8 • r K c L > N Do 'K. \\A O_ nj: G/, ..--rc,..\__________________ U D cn cn a 0)1 y. SCALE 1: 12,00-0 _A I- o N SECTION 29, T1N, REBW, 6th P.M. -r GWS-1 (Rev. April 19,17- STATE OF COLORADO OFFICE OF THE STATE ENGINEER IIVISION OF WATER RESOURCES NONTRIBUTARY GROUND WATER LANDOWNERSHIP STATEMENT I (We) Rick S. Hoffman for Laidlaw Waste Systems, Inc. (Name) claim end say that I (we) am (are) the -owners) of the following described property -consisting of 150.5 acres in the County of Weld —, State of -Colorado: (INSERT PROPERTY LEGAZ DESCRIPTION) A parcel consisting of the NE 1/4 of NW 1/4 plus the NW 1/A _of the NE 1/4 , Section 29, -T1N, R68W, 6th P.M. ; excepting a triangular area in the SW corner of the parcel 570 feet long to the north and 340 feet long to the -east from the SW corner (2 .2 acres more or less) , and excepting a second triangular area in the SE corner of the part-el 740 feet long to the north and 835 _feet long to the west from the SE corner (7 .3 acres -Wore or less) and, that the ground water sought to to withdrawn from the Laramie-Fox Mills aquifer underl-ying the above-described land has not been conveyed or reserved to another, -nor has consent teen given to its -withdrawal by another. Further, I (we) _claim and say that I (we) have read the statements made herein; know -the contents hereof; and that the same are true to my (our) own knowledge. (Signature) (Date) (Signature) (Date) INSTRUCTIONS Please -type or print neatly in black ink. This form may be reproduced by photocopy or work processing -means. See additional instructions on back. 1113 Sherman Street 8th Floor Denver Color-ado 80203 (303) 866-3581 C::0E29 APPENDIX D C Y OF LEGAL INSTR 1 i SHOWING AP ICANT'S INTEREST IN PROPERTY September 1991 913-2324 Golder Associates . . • it4IGtog`/%S AR2121500 D 1' EC 02127500 01/08/88 12136 9.00 1/003 - P 1: .4 MARY 'UMFEUERSTEIN CLERK a EEL AAR WELD CO, CO '5 f I •• RRCOEDa1YTA WNP • Tru DaED,Mdetni. Ith 474 January .1108 ,1 between Colorado Landfill, Inc. '� Stord +vwt1a7 fda ii I reepalattea duly.rgaand and*slating under and by Artae of the tan $ J !//f, JO ,I Mlh.Etate.Colorado attMnr.t pall,and Laidlaw Waste Systems (Colorado) , Inc. i a e.rpe*att.n duty lad end existing under and by virtue of the Wee Ii efth.Mate of Colorado of the second part;whom/legal II address le 60 rg ftSnR dfo.9 A d.nikn.fthesuraofrive Million O�kE ales seventy. T t ;I 9aneAau1�un rar},� see Dusan Six Hundred Forty Eight potl.Ata ,, .l tM tihd• fbXnttf��n • SiT+Y. Mrt11�+41, �g9,fSilFiiaTd'pa`rPy'sl'(bi:econ3 vil'tSii ni�plS�:F«71.hereby ;l teafem ed and acknowledged.ham/granted,bargained,sail and yed.and by thee*presento does grant,bargain, sal,nutty and confirm,ante the said party of the second part,its successors and yatana to .:I the gg..twt II dt.ntbd trpanM or land.altuat601ng and being in the Coun4of Weld and Stele,ideaterde;te.lt:•';i as met teeth on Attachment 1, ' incorporated herein by reference Ilp. II ,i i il ;I II i P '' tin !: l else known asareot and number TOCETNE4 with all and singular the heradltamewn and appurlrnmcn Ihtnunta Miangtng, or in wigwams ' to • epperlaiaine.and the r.rersten and reversions,remainder and remainders,rents,issues end pranta shunt and sit tI a feint.,right,title,interest,claim and demand what.oevet of the said party of the Itnt part,tither in law n equity.of,in and I. m the above bargained premium,with the htrediteeets and appurtenances. fY ITO IIAVE AND TO BALD the said premises above bargained and dbcritad,with the appurtenance.unto the said party orths second part rte a,lee.ew.r.and magna forever.And the said Colorado Landfill, Inc. party of the first part.for Itself,Its igereasara and aegis',doth covenant,grant,bargain and agree to and sit h the said party of the second part, its d staaigns,that at the time of the en.aiing and dellvory of these presents It te well send of the primulas above conveyed.as of good,sure,perfect.shastute and indefeasible estate of I '. Inherltanee,in h..la fre simple, and hath geed right.full power and lawful authority to cant,bargain. sell and l convey the Mama in manner and tarn,af.(elald.and that tN lame are free and Clear from all former sad other rants. i; bar toles,asks.Hens.taxes,"sateem.wts and lne.mhraneaa ofwhatever kind or nature*soy or, except for exceptions as set forth on Attachment 2, incorporated herein by reference. and the above bargained premises In the quiet and peaceable possession of the said party of the second part,its t sucnaaan And assigns against alt end every person or penuns lethally claiming.r to vlain.Ile' mimic re any ,a.t II tb ,the said party ofthe first part shall and will WARRANT AND FOREVER DCYEND. i. IN WITNESS WHIRCOY. The said party .f the reset part bath caused its corporate name to be hereonte ' ssbeerlbed by its presh:ant,and Reverberate seal to be hereunto attta td.attested is Its I, Secet.fi.the day and year not above rrittea. AlhMt ,� Colorado• Landfill, _ _ _ pr1t- tw,e,aq. ay.!•- fee - •—T':.fr— Gary ST.CTLLt1�LnRADe Oat's,. Souders . Ia. eesty of Rnul rims J T . pepsag Instrument tram se kneelrrrrd before me thlt Ith day el January i lista N.L alnny L. Souders .a neaweat and fat::: a tit ,1, - ..r•r•, L. Horton se Seentaryof :V .,,orA� �i'0 atee d ,1 .r.rp.r.tl.n. „ a .•r � 1 WY aMarlale*mmlsolee aaplrea � Iar 9 V t1� ..7 U 1�1.1�+J C Witness m nand and sffklAl uaL /��/11��//))' ✓}� /rr, •. Q y — Wrf(�.r o .*Au;R`�w. t Cr rite' {n .y„Stel�/'Ja.`{u_.._e01�y.�all/ . - .I%se. 'O L:v,,.. .} rail , Mrs pas Jtwoonimas. uaa..r. d ter.enelea.a ly.i..a,.,re togs..,,autos n.a...r...k. Will, 3it 1,, s 11.2 ARC 03127509 01/0•/t• 11,14 ••,00 3/043 r 1250 MART ■.. FSIBRSTRII CL RX • %Doo ss* WELD "I, CO 3).3 WaRRAtfY DEED ATTACHME>t? 2 RECEPTIONS TO TITLE I. ANY AND ALL UNPAID TAXES, MefsSMENTS AID UNREDEEMED TAX SALES. 2. RIGHT OF MAY OVER THE BM 1/4, THE SE 1/4 OF THE SW 1/41 AND THE W 1/2 or THE M 1/2 OF THE NE 1/4 0► SECTION 29, TOWNSHIP 1 NORTH, RANGE 68 WEST OF THE 6TH P.M. CONVEYED BY THE ROCKY MOUNTAIN FUEL COMPANY TO THE CHICAGO, BURLINGTON A QUINCY RAILROAD COMPANY IN DEED RECORDED APRIL 6, 1920, IN BOOK 543. AT PAGE 524. 3. RESERVATION AS CONTAINED IN DEED FROM THE ROCKY MOUNTAIN FUEL COMPANY TO COLORADO LANDPILL, INC., A COLORADO CORPORATION RECORDED SEPTEMBER 17, 1979, IN BOOK 881 AS RECEPTION NO. 1803442, DESCRIBED AS FOLLOWS, 'RESERVING UNTO GRANTOR ALL OIL. OAS AND OTHER MINERALS, EXCEPT THOSE CONSIDERED AS SALVAGE OR BY PRODUCTS FROM LANDFILL OPERATIONS, AND RESERVING UNTO GRANTOR THE RIGHT OF INGRESS AND TO USE SO MUCH OF THE SURFACE OF THE PROPERTY AS IS NECESSARY TO PRODUCE SUCH OIL, GAS AND OTHER MINERALS. ADDITIONALLY, GRANTEE SHALL HOLD HARMLESS THE GRANTOR FROM ANY LIABILITY FOR DAMAGES FROM SUBSIDENCE OR PREVIOUS MINING OPERATIONS WHICH TOOK PlA'E ON SAID PROPERTY..' (AFFECTS PARCXI. A). 4. RESERVATION AS CONTAINED IN DEED FROM THE POCKY MOUNTAIN FUEL COMPANY TO COLORADO LANDFILL, INC., A COLORADO CORPORATION, RECORDED SEPTEMBER 17, 1979, IN BOOK eat AS RECEPTION NO. 1803441, DESCRIBED A9 FOLLOWS, 'RESERVING UNTO THE GRANTOR THE RIGHT OF INGRESS AND EGRESS ON SAID RIGHT OP WAY FOR THE EXPLORATION AND PRODUCTION OF OIL, GAS, AND OTHER MINERALS CU PROPERTY OWNED BY THE GRANTOR IN SECTION TWENTY-NINE (29), TOWNSHIP ONE (1) NORTH, RANGE SIXTY-SIGHT (68) WEST OP THE 6TH P.M. IN WELD COUNTY. COLORADO,. RESERVING UNTO THE GRANTOR ALL OIL, GAS AND OTHER MINERALS. EXCEPT THOSE CONSIDERED AS SALVAGE OR SY-PRODUCTS PROM LANDPILL OPERATIONS, AND RESERVING TO GRANTOR THE RIGHT OF INGRESS AND EGRESS AND TO USE SO MUCH OF THE SURFACE OP THE PROPERTY AS IS NECESSARY TO PRODUCE SUCH OIL, OAS AND OTHER MINERALS. ADDITIONALLY, GRANTEE SHALL HOLD HARMLESS THE GRANTOR FROM ANY LIABILITY FOR DAMAGES FROM SUBSIDENCE OR ANY PREVIOUS MINING OPERATIONS WHICH TOOK PLACE CO SAID PROPERTY.' (AFFECTS PARCEL B.) S. RIGHT OP WAY EASEMENT FOR ELECTRIC PURPOSES GRANTED TO UNION RURAL ELECTRIC ASSOCIATION, INC., BY INSTRUMENT RECORDED OCTOBER 24, 1979, IN BOOK 885 AS RECEPTION NO. 1807275, SAID RIGHT Or WAY EASEMENT BEING DESCRIBED AS FOLLOWS, . 'THE SOUTH 16 FEET or THE' NORTH 46 FEET or SAID EAST 1/2 0? THE NORTHEAST 1/4 AND SAID WEST 1/2 OF THE NORTHEAST 1/4 IN SECTION 29, TOWNSHIP 1 NORTH, RANGE 68 WEST OP THE 6TH P.M.'. 6. TERMS, CONDITIONS, PROVISIONS AND OBLIGATIONS OF OIL AND GAS LEASE FROM THE ROCKY MOUNTAIN 'UM COMPANY AND ENERGY OIL. RECORDED SEPTEMBER 11, 1981, IN BOOK 974 AS RECEPTION NO. 1868804, AND ANY AND ALL SUBSEQUENT INSTRUMENTS RELATING THERETO. 7, NOTES AND DEVELoPMENT IN SOUTHWEST WELD COUNTY LANDFILL SITE MAP RECORDEDRD S AS SHOWN OCTOBER, 979 BOOK 683 AS RECEPTION NO. 1805457. 8. TEEMS AND CCNDLTIDNB OF RESOLUTION BY THE BOARD Or COUNTY COMMI98IONERS 0► WELD COUNTY, COLORADO, RECORDED DECEMBER 15, 1987 AS RECEPTION O. 2124879, • I. TRRMO AND CONDITIONS OF 1NSTRUMEIT RECORDED DECEMBER 1S, 1987 A• RECEPTION NO, 2124880. WDstt2JL• Y'rrR?{`"!n 0 1182 RISC 02127500 01/08/18 12:34 89.00 2/003 r 1249 MARY ANN PEUERSTEIN CLERK $ RECORDER HELD CO, CO ATTACHMENT 1 �•Z NORTHWEST WEST i1/4 OF SECTION 295 TOWWNST 1/4 HPI 1 NORTTH, ARAST AGE OF DE OF T1E 6TH P.M., MELD CDUNTY, COLORADO, LESS TIE FQ.LOwINI CESCR BED ARTS TIEREOF: PMT "A" THE NORTH 30 FEET OF THE SAID WEST 1/2 OF THE NORTHEAST 1/4 AND TIE EAST 1/2 OF TIE NORTHWEST 1/4 Of SECT ION 29, TOWNSHIP 1 NORTH, RMGE 68 WEST OF TIE 6Th P.M., WELD COUNTY, COLORADO MARFIELD STREET RIOM-OF-WAY• ). PMT '13" BEG INNING AT THE SOUTHEAST CORDER OF THE SA ID WEST 7/2 OF TIE NORTHEAST 1/4 OF SECTION 29, TOWNSHIP I NORTH, RANGE 68 WEST OF THE 6114 P.M., WELD COUNTY, OOLORADO$ THENCE N. 89'24'08■ W., ALOMG TIE SOUTH LINE OF TIE SA ID WEST 1/2 OF THE NORTHEAST 1/4, 835.82 FEET; THENCE N. 49.00'15" E., 1114.06 MET TO A POINT ON TIE EAST LINE OF THE SAID WEST 1/2 OF THE NORTHEAST 1/4; THENCE S. 00.04'57" W., ALOIG THE SAID EAST LINO, 739.59 FEET TO TIE PO INT Of EEO INN 110. PMT 'G" BE3tNNIIG AT TIE SOUTHWEST CORNER OF THE SAID EAST 7/2 Of THE NCRT144EST 1/4 OF SECTION 29, TOWNSHIP 1 NORTH, RANGE 66 WEST OF THE 6TH P.M., WELD COUNTT, COLORADO; THENCE M. 00'02'01" W. ALOIC THE WEST LINE OF TIE SAID EAST 1/2 OF TIE NORIHEEST 1/4, 570.17 FEET; 'PENCE S. 30'35'34" E., 666.48 FEET TO A POINT ON N. 5IE r024'O6"W.,, R.OHG TIE S Of THE SA ID AID SCUTHT 1/2 F DE LINE, 3388.06 FEETST 4; THENCE TO THE POINT OF DEO INNIN3. • • • I I APPENDIX E T OF PROPERTY 0 September 1991 913-2324 Golder Associates ATTIDAVIT Of INIZREST -UWNER° SURFACE ESTATr -Application No. Subject Property TIM NE1/4NW1/4 AND THE HW1/4NE1/4 OF SECTION 29, TOWNSHIP 1 NORTB, RANGE 68 WEST OF T F.FT. . WEL; cuuz11r, LiCCMCCr EXCEPT TWO PARCELS STATE OF COLORADO ) as. BOUNTY OF WELD ) THE UNDERSIGNED, being first duly sworn, states that to the best of his or her knowledge the ettsched list fie a true and accurate list of the names, addresses and the corresponding Parcel Identification Number assigned by the -Meld County Assessor of the owners of property (the surface estate) within five hundred (500) feet of the property subject to the application. This list was compiled from the records of the Weld County Assessor, or en ownership arpdate from a title or abstract company or attorney, derived from such records, or -from the records of the Weld County Clerk and Recorder. The list compiled from the records of the Weld County Assessor shell have bean assembled within thirty (30) days of the application subaisaion date. e filar: RUDY L. WELD COUNTY ITLE COMPANY The foregoing instrument was subscribed and sworn to before me this _,. day of ?_7 , . 19, ,. -WITNESS my hand and o-fficial seal. My floeaj ,ton. expires: oar4.0S fe , '€41ARr,7 � _, tar 1 n ?l/X[s/' • o Y � t`.' • or .•' £ 0 • d - F4 _13 -1 >l ' 31 .AOa ' 3aHH r T Z : sr }-10 W T ._. - 0z^. - d3S • ADDRESS, TOWN/-CITY, AS-BFSBCR'l PAMMCEL NA18 STATE AN, ZIP LODE flENTITI_CATION 0 Laidlaw -Waste Systems PLO, Box 122283 14422-9000006_ pt. -Worth. 1X. 76111 Cencall Inc, 1999 Bros��L,v /2'00 14672 900009 -Denver. CO -80202 Colorado Landfill Inc. I Bob Mc$enzis 1_467.29QDf1020 �-- 8,0. Sox 111283 • 7T, W¢tih, IX 7611¢ IPrett, Kenneth E. P.O. Box 801 _14672QQQ=042 and Landers, Karen K. Longmont , CO 805Q1 Coaelett, Richard 1Lonsmont National Bank 1467/0000010 Verney, Effie E. Armstrong, Ray 5th & Coffman Collins, Beverly J. - 7ease, June Ann Longmont, CO 80501 Gilkineon, Betty Jean Cose_laatt GSX Denver Regional X Bob McKenzie 14,720000011 Landfill Inc. P.O. Box 122283 ft. Worth, TX 76116 • -b.-0 - -- - N _I 31 >i 3 -1 J, O tZ ` 3 HS Z : S I NOW t 6 -8s - d 3 = ' APPENDIX F LIST 0 i i RAL OWNERS AND i .SEES I I I September 1991 913-2324 Golder Associates CT—n."471'3 - ".s Application No. Subject Property THE NEI/4NW1/-4 AND THE NWi/-4NE1/4 OF SECTION -29, TOWNSHIP N01trd, MANGE 68 WEST OF THE 6TX P.M. , WELD COMM, COL_ORADO EXCEPT 1440 PARCELS STATE OF COLORADO ) • COUNTY 07 WELt ) THE1JNDERSI_ONED, being first duly sworn, states that to the 'bast of his or her knowledps the -attached list is a true and accurate list of the names and addresses of all mineral owners and losses of mineral owners vn or urt-der the parcel of land which is the -subject of the application as their -names appea-r upon the records in the Weld -County Clerk end Recorder's _Office, or from en ownership update from a title or abstract compeny or en attorney, • RUDY L. -MFRS WELD COUNTY TITLE COMPANY The for-s$oing instrument was subscribed end sworn to before era this 3304 /day of b.,41+4 WITNESS my hand end Otitis' seal, +lU' d41!tp,.ycpireef o'J/b O 1 s otarOr lie lithei _ r,,,CL 3 NAMES ^' OWNERS bP MINtRAL9 ANT) _SASSES OP MINSRA -" • Rocky Mountain Fuel Company A1.1 nil, Gas and other Miner 1 _ 91n 15th Street x'756 Denver, CO 80302 AN'D 608 Emnxire 2�u11dinTt Denver, 40 80203 Leese* on 011 and Gas Lease Energy Oil, Inc. 17801 L-efthand -Circle Longmont, CO x0501 Assignee bf Ott And nee Lean $ny4er.-01 Patters I.P. , A _Delaware limited -partnershi-p r_ 2500 Interfirlt Tower, • Tort Worth.' TX 76102 AND 2500 -Tint Republia3ank Tower _Fort Worth, TX 76102 AND 1800 Glenarm dace, Setts 70-0 Denver, CO 80202 • 9E d -1 ' NIS1 :1 ^zt : ST NOW -T6- 02 -z13S ©A jitailAr L-AIDLAW WASTEIYSTEMS INC. DENVERRREGIONAL LANDFILL SPECIAL WASTE ACCEPTANCE PLAN DENVER REGIONAL LANDFILLS (NORTH AND SOUTH) February 13 , 1992 1441 WELD COUNTY ROADS, P:O. BOX-320, ERIE,COLORADO 80516 (303) 673-9431 Special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems, Inc. TABLE OF CONTENTS Page 1. 0 INTRODUCTION 1 2 .D DEFINITION OF SPECIAL WASTE 2 3 . 0 WASTE CHARACTERIZATION & ACCEPTANCE 5 3 . 1 SPECIAL WASTE ACCEPTANCE APPLICATION 5 3 .2 LAIDLAW EVALUATION OF WASTE CHARACTERISTICS . 7 4 . 0 SPECIAL DISPOSAL PROCEDURES 10 4 . 1 OFF SPECIFICATION PRODUCTS 10 4 .2 NONFRIABLE ASBESTOS 10 4. 3 MEDICAL WASTES 12 4 .4 COAL & OTHER FOSSIL FUEL ASH 12 4 . 5 CONTAMINATED SOIL 13 5. 0 RECORD-KEEPING 14 LIST OF 'TABLES Table 1. Special Wastes and Analytical Guidelines 1-6 Table 2 . Waste Acceptance Characteristics 1S LIST OF ATTACHMENTS Attachment I. Special Waste Acceptance Application Attachment II. Sampling Information Form Attachment III. Special Waste Disposal Agreement Attachment IV. Transportation Farm Att-achment V. Spacial Waste Notification Form -i- ecrnr-rtri Special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlew Waste Systems, Inc. 1. 0 INTRODUCTION This is a special waste acceptance plan applicable to the Denver Regional Landfills (North and South) . Both sites are sanitary landfills and are permitted to routinely accept non-hazardous, non-radioactive garbage, refuse and other solid discarded material including industrial, commercial, agricultural, community, and residential wastes. This plan -defines special wastes, establishes methods of waste characterization and sets criteria for the acceptance of special waste for disposal at the sites without additional review by the regulatory agencies. In addition, the plan presents disposal procedures for special wastes and zlescribes the records maintained for disposal of special wastes. -1- Special Waste Acceptance Plan Denver Regional Landfills - February 13 , 1992 Laidlaw Waste Systems, Inc. 2 . 0 DEFINITION OF SPECIAL WASTE Special wastes are any non-hazardous solid wastes that require specialized collection, handling, or disposal practices in order to manage them in an environmentally sound manner or that require chemical characterization prior to disposal to establish that they are not hazardous wastes. Specifically, a waste material is a special waste if it meets either of the following criteria. 1. The waste is listed on Table 1. 2 . The waste is other than one of the specifically exempted wastes under the RCRA regulations (40 CFR 261. 4 (b) ) . The RCRA exempted wastes include household wastes, solid waste from commercial or industrial sources that do not contain hazardous waste, and most farm and agricultural wastes. There are many special wastes that can be accepted for disposal in an environmentally sound manner. The following is a list of -examples of special wastes; however, the list is not meant to be all inclusive. Examples of special wastes are as follows: o Sludges, o Waste from an industrial manufacturing process, o Waste from a pollution-control process, o Solid residual or debris from clean-up of a spill _or release of a chemical substance, o Off-specification products, o Ash from combustion of municipal solid waste or medical wastes, o Print shop wastes, o Paint spray booth wastes, -2- Special Waste Acceptance Plan Denver Regional Landfills February 13 , 19-92 Laidlaw Waste Systems, anc. o Dry cleaning wastes, o -Medical wastes, o Asbestos containing wastes, o Fuel contaminated soils, o Demolition debris from industrial facilities, o Industrial equipment removed from service, o Grease trap wastes, o Absorbed wastes produced from maintenance of vehicles and equipment (e.g. , oil and anti-freeze) , o ash from the combustion of coal or other fossil fuels for power or steam generation, o PCB containing wastes, and o empty containers. These materials and any other wastes that are not specifically exempted under RCRA must be characterized and formally accepted for disposal (-as described in Section 3 of this plan) prior to acceptance at the landfills. The intent of this document is to describe the waste character- ization and acceptance procedures used at the Denver Regional Landfills so that individual approvals for each special waste will not be required from the local regulating agency (Town of Erie or Weld County Health Department) and the Colorado Depart- ment of -Health. However, it is recognized that certain special wastes will still -require specific approvals. One of these is sludges from potable water treatment plants (alum sludge) . Alum sludge will be accepted only after analyses as _required in -3- N•.d CCJ is Special Wast-e Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidl-aw Waste Systems, Inc. Section 12 of the Colorado Department of _Health regulations are performed and specific regulatory approval is obtained. -4- l`^nLE!1 .s.;:a,r cii:.d3 Special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems, Inc. 3 . 0 WASTE CHARACTERIZATION & ACCEPTANCE All special wastes are carefully characterized prior to accep- tance at the Denver Regional Landfills. The first step in the characterization -consists of preparation of the Special Waste Acceptance Application (SWAA) . The SWAA is then reviewed at the Regional Office (Arlington Heights, Illinois) and the waste characteristics are compared to established Laidlaw standards. In general, the waste acceptance standards are a minimum of twenty percent lower than the federal and state standards. If it is =determined that the waste can be handled safely and that it is appropriate material for disposal at the site, the SWAA is approved and the landfill can accept the material. This process is 'described in more 'detail below. 3 . 1 SPECIAL WASTE ACCEPTANCE APPLICATION The SWAA (Attachment I) will be completed using the following guidelines. 1. The application will be complete and legible. All signa- tures will be present. Any additionsor corrections to the signed SWAA win be initialed and dated. 2 . All information concerning the Generator will be provided. 3 . The -General Material Description will contain sufficient information to give the reviewer a clear understanding of the natureof the waste. 4 . The Waste Quantity and Frequency of Receipt will be estimated as accurately as possible. 5. The Process Generating Waste section will provide suffi- cient detail to -allow an -evaluation of whether the waste is a listed hazardous waste (specific or non specific source) . Listed hazardous waste will not be accepted. -5- .J. . J a a.'> • Special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems, Inc. 6. Laboratory analyses will be performed to characterize the waste, as appropriate, in order to complete the sections for Physical Properties, Chemical Properties and Other. Table 1 presents various special waste types together with the analysesrequired for their characterization. For many wastes, the first step in the characterization process involves checking that the waste is not a listed hazardous waste under 40 CFR 261. 31, 2-61. 32 and 261. 33 (List column on Table 1) . The laboratory report of any analyses will be attached to the SWAA and will contain the following: a) project description, b) results, c) analytical methods, d) chain of custody form, and e) quality assurance data. A Sampling -Information Form (Attachment II) will be completed for -any special waste sample. 7 . -The Other Informati-on section will be _completed in its entirety, including the following. The method of delivery will be specified. Approval by local and state regulatory authorities will be indicated; however, the purpose of this plan is to set special waste acceptance criteria for which additional regulatory approvals are not required. Thus, regulatory approval will only be required for special wastes that exceed the acceptance criteria presented herein, but which are nonetheless believed to be appropriate for disposal at the Denver Regional Landfills. Material Safety Data sheets (MSDS) will be provided for any of the following, when applicable: o Laboratory wastes, o Empty -containers, o Industrial equipment removed from service (for chemi- cals used in the equipment) , o Off-specification products, o Spill residues, -6- • • Special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems, Inc. o Paint wastes (paint and solvents) , and o Print shop -wastes (inks and solvents) . For virgin product material, a valid MSDS may be satisfac- tory documentation of the physical and chemical properties of the waste. The MSDS may also provide disposal informa- tion. 8 . The Generator Certification will be completed by the generator, certifying that the information on the SWAA is accurate and that the material is not a hazardous -waste. In addition to the generator certification on the SWAA, a Special Waste Disposal Agreement (Attachment III) will be completed by the generator (party responsible for disposal charges) documenting the representation by the generator that the special waste is not a hazardous waste. The SWAA, together with appropriate attachments (i.e. , sampling form, laboratory analyses, regulatory approval, MSDS, and special waste disposal agreement) will be sent to the Division Manager at the disposal site and then to the Regional -Office for evaluation. 3 . 2 LAIDLAW EVALUATION OF WASTE CHARACTERISTICS Every SWAA received at the Regional Office is carefully reviewed by the Regional Engineer or the Technical Services Represen- tative. The review is performed as follows. 1. -The SWAA is inspected for completeness and signatures. A SWAA must contain information concerning the generator, waste volume and waste type. 2 . The waste material and the process from which it is derived are checked against 40 CFR 2_61. 31, 2-61. 32 and 2_61. 33 to determine that the materiel is not a listed waste. A listed waste may ay be from non-specific (F list) or specific -7- Special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems. Inc. (K list) sources, or may be discarded commercial chemical products (Acute Hazardous or Toxic Chemical listings) . Listed wastes are hazardous wastes and will not be accept- ed. 3 . The waste analysis or MSDS is reviewed to determine if the material exhibits any hazardous waste characteristics. 4 . The chemical analysis is reviewed and the quality assurance (QA) data are checked. In no event will a waste be accepted if the material properties indicate that it is a hazardous waste by characteristics (40 CFR 261. 20 through 2-61. 24) . The characteristic concentrations are shown in the second column of Table 2 . The concentrations that Laidlaw brill accept (the Acceptance Criteria) are shown in columns 3 and 4 of Table 2 . Slightly higher concentrations are acceptable for materials that were analyzed with a matrix spike than for those that were not. However, the acceptable concentrations are all lower than the RCRA hazardous-by-characteristics concentrations (at least ten percent lower) . 5. The size, contained material and emptying or cleaning procedures are reviewed for all empty containers to evaluate whether they meet the criteria for empty according to 4D _CFR 2-61.7. Containers are empty if: a) (for wastes other than a compressed spas or an acute hazardous waste) no more than one inch of residue remains in the bottom, or no more than 3 percent by weight remains in a container of 110 gallons or less, or no more than D. 3 percent by weight remains in a container larger than 11D gallons, b) (for a compressed -gas) the pressure in the container is near atmospheric, or c) (for an acute hazardous waste) the container has been triple rinsed using -a solvent capable of removing the material originally in the container, ar the container has been cleaned by another method that has been proven to be effective, or the container had an inner liner that prevented contact of the contained material with the container and the inner liner has been removed. Only empty containers will be accepted. -8- • Special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems, Inc. 6. The physical properties of the waste are reviewed to determine if the material will require special handling during the haul or at the landfill. Special handling or other requirements are added by the reviewer, as appropri- ate, and entered in the Conditions for Acceptance section of the SWAA. The conditions may include a requirement for semiannual, annual or biennial recertification of the waste characteristics. If the waste is acceptable for disposal, the SWAA will be signed and dated by the reviewer and the other indicated personnel in the For Office Use Only section of the SWAA. -9- Special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems, Inc. 4. 0 SPECIAL DISPOSAL PROCEDURES In general, special wastes are handled _during disposal in a manner similar to routine wastes. The special wastes will be unloaded at the working face -and covered as necessary to minimize wind dispersal and control vectors. Every load of special waste will be accompanied by a Transportation Form (Attachment IV) and must have an approved SWAA on file at the disposal site. If a special waste -arrives at the site without the proper paperwork, a Special Waste Notification Form (Attach- ment V) is completed and the load is refused. The following sections describe special disposal procedures for off-specification products, asbestos containing material, medical waste, ash from the combustion of coal and other fossil fuels, and contaminated soils. 4 . 1 OFF-SPECIFICATION -PRODUCTS Off-specification products will be promptly covered with refuse or soil to minimize scavenging. Scavenging is prohibited at the Denver Regional Landfills. 4 . 2 NONFRIABLE ASBESTOS Asbestos containing material (ACM) will be handled in a manner to minimize air emissions during disposal . ACM is any material containing more than 1 percent asbestos by area, as _determined using Polarized Light Microscopy. The Denver Regional Landfills will only accept nonfriable asbestos (ACM, that when dry, cannot be crumbled, pulverized or reduced to powder by hand pressure) . -10- a-0 "r n Special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems, Inc. Examples of typical nonfriable ACM are packings, gaskets, resilient floor tiles, asphalt roofing and exterior siding products. An approved SWAA providing the analytical information concerning the type of ACM, friability determination and the approximate material quantity must be on file prior to disposal. All dumpsters containing nonfriable asbestos must be enclosed in a tarp prior to loading and during the haul to the site. The vehicle hauling the ACM must be placarded with the following. DANGER (1 inch block) (1 inch space) ASBESTOS DUST HAZARD (1 inch block) (1 inch space) CANCER AND LUNG DISEASE HAZARD (3/4 inch block) (1 inch space) Authorized Personnel Only (14 point Gothic) These markings must be visible from all sides of the dumpster, and must be displayed during loading and unloading of the ACM. ACM will be unloaded et the base or side of the working face. Other wastes will be used to cover the ACM as soon as possible. The ACM will be completely covered by two feet of non-ACM prior to trafficking -by landfill equipment so that the equipment does not contact the ACM. ACM will not be placed within 25 feet of an -outside slope (measured horizontally) nor within as feet of the final grade. The disposal location will be approximately identified using site coordinates and elevation and noted on both the Transportation Form and the gate receipt. -11- Special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems, Inc. 4 . 3 MEDICAL WASTES All medical wastes will be rendered non-infectious prior to disposal by steam autoclave or other appropriate means (chemical or germicidal treatment) . Used sharps (e.g. , needles and scalpels) must be in an approved sharps container and the container must have been rendered non-infectious. Body tissue and fluids are not allowed. Generators must supply their standard operating procedures for disinfection and their Facility Operating Plan as described in Section 13 . 6 . 4 of the Colorado Department of Health regulations prior to acceptance of any wastes. Laidlaw may require other guarantees and may audit the disinfection process. Medical waste will be unloaded at the base or side of the working face. Other wastes will be used to cover the medical waste as soon as possible. The medical waste will be completely covered by two feet of other waste prior to trafficking by landfill equipment so that the equipment does not contact the medical waste. Medical waste will not be placed within 25 feet of an outside slope (measured horizontally) nor within 15 feet of the final grade. 4 .4 COAL & OTHER FOSSIL FUEL ASH Fly and bottom ash from the combustion of coal and other fossil fuels will be placed at the working face with other refuse. All loads will be covered and inspected for evidence of drippage of ash or water during the haul. If the ash contains free liquids, the ash will be spread at the point of generation to enhance drying so that there will be no free liquids in the load at the -12- r*c^n.^ Special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems, Inc. time of unloading. Alternatively, the ash will be moisturized as necessary (at the point of generation) so that there will be sufficient moisture in the ash to limit fugitive dust at the time of unloading. After unloading, the ash will be covered with refuse or soil so that complete coverage is achieved in approximately an hour. Prompt cover placement is intended to minimize particulate emissions (fugitive dust) from the disposal operation. 4. 5 CONTAMINATED SOIL Contaminated soil will be used for daily or intermediate cover to the extent possible. If the soil cannot be used for cover because of site conditions, the soil will be placed at the working face and handled as normal refuse. If feasible, the soil will be spread and aerated before use. Contaminated soil waste will not be placed within 25 feet of an _outside slope (measured horizontally) nor within 15 feet of the -final grade. -13- Special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems, Inc. 5. 0 RECORD-KEEPING A filing system is maintained at the disposal site documenting all special wastes accepted. A separate file will be estab- lished for each waste. The file will contain the original approved Special Waste Acceptance Application (SWAA) with accompanying documentation which will include the following, as appropriate: o Material Safety Data Sheet (MSDS) , o Sampling Information Form, o Laboratory analytical results, o Special handling or recertification requirements imposed by the Regional Office, and o Local and state approvals, if required. The special waste file will also contain the Transportation Form documenting the date of receipt of the waste. The Transporta- tion Form will show the site coordinates and elevation at which all ACM wastes are disposed. The general location of other special wastes can also be determined by cross-referencing the date of disposal on the Transportation Form to the file records kept regarding areas and elevations filled each month. Other files associated with the _disposal of special wastes are also maintained at the site. Special Waste Disposal Agreements are kept on-file documenting the representation by the generator that the special waste is not a hazardous waste. A copy of the Standard Operating Procedures (SOPS) and Facility Operating Plan submitted by the generator detailing disinfection procedures is -14- Special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems, Inc. filed with the Special Waste Disposal Agreement for medical wastes. In addition, gate receipt files are maintained on both an alphabetical (monthly) and chronological basis. Both the date and time of entry are noted on the gate receipts. Gate receipts for ACM loads are annotated with the general location (site coordinates) and elevation of the actual disposal site. -15- r � «ug Special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems, Inc. Table 1. Special Wastes and Analytical Guidelines L RCRA T B P M S Special i C TTT C S 0 Waste s Ignit Corro Reac L E E V Paint B D P Type t able sive tive P X H H Filt. s Ss --- --- --- --- --- --- --- --- Sludges from POTW * * * * Food Processing * * * Oil-Water Separator * * * * * * Industrial Wastewater Treatment * * * * * * Vehicle Wash * * * * * * - ---- --- --- --- --- --- --- Industrial Mfg Process Wastes * * * * * * * * - ---- --- --- --- --- --- --- Spill . Cleanup * * * * * * * * --- ---- --- --- --- --- --- --- Off Spec Product * * * * * * --- ---- --- --- --- --- --- --- Incinerator Ash from: MSW * *1 * * * Med Waste * *1 * * * --- ---- --- --- --- --- --- --- Ash from Coal & Fossil Fuels * *1 * - ---- --- --- --- --- ---Restaurant Grease Traps * * * --- ---- --- --- --- --- --- --- Print Shop * * * * * * -16- Special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems, Inc. Table 1. Special Wastes and Analytical Guidelines (continued) L RCRA T B P M S Special i C TTT C S 0 Waste s Ignit Corro Reac L E E V Paint B DP Type t able sive tive P X H H Filt. s Ss --- ---- --- --- --- --- --- --- Paint Shop * * * * * * -- ---- --- --- --- --- --- --- Dry Cleaning * * * * * * --- ---- --- --- --- --- --- --- Medical Waste * * * --- ---- --- --- --- --- --- --- Scrap Processing * * * * * - ---- --- --- --- --- --- --- Vehicle Maintenance * * * * * * * --- ---- -- --- --- --- --- --- Empty Containers * * * --- ---- --- -- --- --- --- --- UST Soils Contaminated with Diesel * * * * Gasoline * *2 * * * Waste Oils & Solvents * * * * * * * * * Mixed Fuels & Oils * * * * * * * Product Solvents * * * * * * Unknown * * * * * * * * Asbestos % by Area (Polarized Light Microscopy) Friability Determination *1. TCLP metals only *2 . TCLP lead only -17- special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems, Inc. Table 2 . Waste Acceptance Characteristics RCRA Acceptance Acceptance Characteristic Hazardous Criteria Criteria Criteria w/o Matrix w/ Matrix Spike Spike Flash <60 C Ignitability Burns Flash > 75 C Flash > 75 C Vigorously (167 F) (167 F) = 2 > pH or Corrosivity > 12 corrosion 3 < pH <11. 5 3 < pH <11. 5 rate > 6. 35 mm/yr @ 55C Free CN Free CN Reactivity Stability < 250 mg/1 < 250 mg/1 with Free SO3 Free SO3 H2O, CN, S < 250 mg/1 < 250 mg/1 Method 1311 Method 1311 Method 1311 Toxicity (TCLP) (mg/1 in (mg/1 in (mg/1 in extract) extract) extract) METALS Arsenic 5 1 4 Barium 100 20 80 Cadmium 1 0. 2 0. 8 Chromium 5 1 4 Lead 5 1 4 Mercury 0 . 2 0. 04 0 . 16 Selenium 1 0. 2 0 . 8 Silver 5 1 4 -18- eFireen Special Waste Acceptance Plan Denver Regional Landfills February 13 . 1992 Laidlaw Waste Systems, Inc. Table 2 . Waste Acceptance Characteristics (continued) RCRA Acceptance Acceptance Characteristic Hazardous Criteria Criteria Criteria w/o Matrix w/ Matrix Spike Spike Method 1311 Method 1311 Method 1311 Toxicity (TCLP) (continued) (mg/1 in (mg/1 in (mg/1 in extract) extract) extract) VOLATILES Benzene 0. 5 0. 1 0 . 4 Carbon Tetrachloride 0.5 0. 1 0. 4 Chlorobenzene 100 20 80 Chloroform 6 1.2 4 . 8 1, 2-Dichloroethane 0. 5 0. 1 0. 4 1, 1-Dichloroethylene 0.7 0.14 0. 56 Methyl Ethyl Ketone 200 40 160 Tetrachloroethylene 0.7 0. 14 0. 56 Trichloroethylene 0.5 0. 1 0. 4 Vinyl Chloride 0. 2 0. 04 0. 16 SEMI-VOLATILES o-Cresol 200 20 160 m-Cresol 200 20 160 p-Cresol 200 20 160 Cresol 200 20 160 -19- Special Waste Acceptance Plan Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems, Inc. Table 2 . Waste Acceptance Characteristics (continued) = aaxsm.= = RCRA Acceptance Acceptance Characteristic Hazardous Criteria Criteria Criteria w/o Matrix w/ Matrix Spike Spike Method 1311 Method 1311 Method 1311 Toxicity (TCLP) (continued) (mg/1 in (mg/1 in (mg/1 in extract) extract) extract) SEMI-VOLATILES (cont) 1, 4-Dichlorobenzene 7 .5 1.5 6 2 , 4-Dinitrotoluene 0. 13 0. 026 0. 104 Hexachlorobenzene 0. 13 0. 026 0. 104 Hexachlorobutadiene 0 . 5 0. 1 0. 4 Hexachloroethane 3 0. 6 2 .4 Nitrobenzene 2 0.4 1. 6 Pentachlorophenol 100 20 80 Pyridine 5 1 4 2 , 4 , 5-Trichlorophenol 400 80 320 2 , 4, 6-Trichlorophenol 2 0. 4 1. 6 PESTICIDES/HERBICIDES Chlordane 0. 03 0. 006 0. 024 2 , 4-D 10 2 8 Endrin 0. 02 0 . 004 0. 016 Heptachlor 0. 008 0. 0016 0 . 0064 -20- r/^n r Special Waste Acceptance Plan -Denver Regional Landfills February 13 , 1992 Laidlaw Waste Systems, Inc. Table 2 . Waste Acceptance Characteristics (continued) s RCRA Acceptance Acceptance Characteristic Hazardous Criteria Criteria Criteria w/o Matrix w/ Matrix Spike Spike Method 1311 Method 1311 Method 1311 Toxicity (TCLP) (continued) (mg/1 in (mg/1 in (mg/1 in extract) extract) extract) PESTICIDES/HERBICIDES (continued) Heptachlor Hydroxide 0. 008 0. 0016 0 . 0064 Lindane 0. 4 0. 08 0. 32 Methoxychlor 10 2 8 Toxaphene 0. 5 0. 1 0. 4 2 , 4, 5-TP (Silvex) 1 0.2 0. 8 OTHER CHARACTERISTICS mg/1 mg/1 unless noted unless noted Paint Filter (Free Liquids) >0% 0% 0% TEH or TVH 1O, 000 10, 000 BTEX 1, 000 1, 000 PCBs 50 25 25 Minimum % Solids POTW Sludge 20% 20% Minimum % Solids All Other Material 40% 40% -21- ATTACHMENT I SPECIAL WASTE ACCEPTANCE APPLICATION i Code a 613 8 3 fl4B &42Yspeciai Waste Acceptance Application Generator Name: Originating Division: Address: Disposal Facility: Location: Telephone:( ) Waste Quantities: Units:Cubic Yds.❑ Tons Generator Contact: Frequency of Receipt: Daily❑ Weekly❑Monthly❑ One Time❑ General Material Description: Other Process Generating Waste: Physical Properties:Physical State at 7lPR Solid❑ Semisolid❑ Liquid❑ Density: &CY Color: Viscosity: Low❑ Medium❑ High El Hash Point: °F Odor: Yes❑ No El Water Content: %by Weight Paint Filter Test: Passed❑ Failed❑ Reactive: Non Yes❑ With Waste pH: Infectious: Yes❑ No❑ Chemical Properties:(Concentrations in mg/I) (TCLP) Arsenic m-Cresol Hexachlorobenzene Pyridine Barium p-Cresol Hexachlorobutadiene _ Selenium Benzene Cresol Hexachloroethane Silver Cadmium 2,4-0 , Lead Tetrachloroethylene Carbon Tetrachloride 1,4 Dichforobenzene Lindane Toxaphene Chlordane 1,2 Dkhloroethane Mercury Trichloroethylene Chlorobenzene 1,1-Dkhloroethylene Methoxychlor 2,4,5-Trichlorophenol Chloroform z4-Dinitroto/uene Methyl Ethyl Ketone 2,4,6-Trichlorophenoi Chromium Endrin _ Nitrobenzene 2,4,5TP(Silver) o-Cresol Heptachlor Pentach/orophenol Vinyl Chloride Other(list): Other Information: Delivery Method: Bulk O Other Regulatory Agency Approval Received: Yes 0 No❑ Permit Number Matedal Safety Data Sheet Provided: Yes❑ No❑ GENERATOR CERTIFICATION To the best of my knowledge,the information FOR OFFICE USE ONLY provided above is accurate and the material is Conditions for Acceptance not classified as a hazardous waste in accordance with current regulations. Authorized Representative 1. Originating Division Manager Date Signature 2. Disposal Facility Manager Date Name 3. District Manager Date Title ._ 4.Regional Engineer_ __ _ _ Date Date Recertification Frequency: Si Annual❑ Annual ^ Semi Annual •.i.. v L.,l.'13 INSTRUCTIONS This form must be completed for all special wastes to be considered for transportation,storage,treatment or disposal by Laidlaw. All questions must be answered and the answers must be entered on the form in ink. Responses of"None"or"Not Applicable"may be made if appropriate. The various items on the form are explained below. Generator Name and Address: Name and location of facility producing the waste. Generator Contact: A person who could provide additional information about the waste if needed. General Material Description: A name which describes the waste in general terms. Process Generating Waste: Specific process or source which produces the waste. Laidlaw Facility: Laidlaw facility initiating this application. Disposal Facility: Name of disposal facility to which waste will be sent. Physical Properties: The physical character of the waste must be described according to the properties outlined. Chemical Properties: The chemical character of the waste must be described using the paramaters listed to insure that it is not a hazardous waste. Other Information: The method by which the waste will be contained for delivery(e.g.bagged,bulk,etc.). Regulatory approval data for disposal of the waste in the disposal facility. Provide a material safety data sheet,if available. Include any additional infor- mation you feel may assist with the evaluation of the waste. Generator Certification: An authorized representative of the company generating the waste must confirm by signature the accuracy of the information provided and that the waste is not hazardous under current regulations. The following list of wastes are classified by Laidlaw as"Special Wastes"and must be submitted for review using this form. I. Sludge wastes including those from domestic septic tanks,POTW's,food processing plants,industrial wastewater treatment plants,oil water separators,vehicle washing facilities,etc. 2. Industrial Manufacturing Process Wastes including foundry sands,diatomaceous earth,filter cake.etc. 3. Solid residual or debris from clean-up of a spill or release of product. 4. Off-specification,contaminated,spoiled,outdated or banned products and chemicals. 5. Ash from the incineration of municipal solid waste or medical waste. 6. Grease trap wastes from restaurants,hotels,etc. 7. Print shop wastes. 8. Paint spray booth wastes. 9. Dry cleaning wastes such as spent filters. 10. Medical wastes from hospitals,medical practitioners,clinics,nursing hoines,mortuaries,testing laboratories,veterinary clinics,etc. II. Animal waste and grease from slaughterhouse and rendering plants. 12.Asbestos containing waste. 13.Demolition debris from decommissioned industrial facilities. 14. Chemical process or storage plant removed from service(e.g.storage tanks,reactors,pipe work,etc). 15:Waste produced from vehicle maintenance facilities. 16. Landfill leachate and gas condensate removed from landfills. 17. Chemical-containing equipment removed from service including batteries,thermometers,fluorescent tubes.etc. 18. Chemical-,fuel-or oil-contaminated soils. 19. Empty chemical,paint or oil containers such as drums,pails,cans,etc. 20. Used tires. 21. Laboratory wastes. ATTACHMENT II SAMPLING INFORMATION FORM Aga DoL;A© Sampling Information 1.A Sampling time: date time 1.8 Sampling location(be specific: hopper,drum,excavation,tank,etc.): 1.C Sampler's Name Telephone 1.D Sampler's Firm(if different from Generator) 1.E Address City State Zip Phone 1.F Was a Generator's representative present during sampling? yes no 1.G Briefly describe sampling method and-equipment used: Representative Sampling Certification I hereby certify that the methods and equipment descnbed above in section 1.0 are an accurate report of the sampling procedure used. I also canary that the above-mentioned methods resulted in obtaining a sample that is representative of the waste. Sampler's Signature Witness'Signature' 'It the sanpleris not an employee of the generator,the generator should provide a witness during the sampling. ATTACHMENT III SPECIAL WASTE DISPOSAL AGREEMENT SPECIAL WASTE DISPOSAL AGREEMENT This Agreement is for Special Waste as defined by Laidlaw and containing the physical and chemical properties outlined in the Special Waste Acceptance Application attached hereto as Exhibit"A",code number: DIVISION SWAA CODE The customer represents that this Special Waste Is not a'Hazardous Waste'as defined by USEPA 40 CFR Part 261 or the state in which the Special Waste is to be generated.stored and/or disposed of.Customer agrees to Indemnify and save harmless Laidlaw from any and all damages or claims of any kind or metre arising out of LadlaWs receipt and disposal of the Special Waste.In the event lit Special Waste is later determined to be Hazardous or is later redefined as Hazardous or otherwise deemed unacceptable by Laidlaw this Agreement,In addition to the above hiderenity,will be subject to immediate termination by Laidlaw,irs subsidiaries or the Customer. 1. During the term of this Agreement Customer will utilize the services of Laidlaw To dispose of the quantities of Special Waste as listed in Exhibit"A"or as noted below. (Note if volumes or other items are guaranteed) Other items 2. Laidlaw agrees to provide Customer with the following services and/or equipment. disposal facility will cause the disposal of the Special Waste at a dis P fully permitted to accept and dispose of the described Special Waste. Other services as described below: (Customers initials on lines indicates acceptance.) 3. Laidlaw will provide services Customer desires within the following constraints(indicate hours,minimum or maximum loads,or other operational limitations to accepting the Special Waste.) 4. Customer agrees to pay the following charge to Laidlaw for services as described herein:ill be Increased to cover Increases In federal,and bat fUnless ees otherwise mposed during the term of thisng will be yaaw agreement a ment payableo ncreased dispoossal charges of s however all t Charges iIncreases shag be communicated by prior writtente. notes.)LaWew shall have the right to refuse acceptance of any Special Waste during any period of time that customer is past due in its payments. 5. This agreement will be for a term of_ years from the date of signing,subject to the right of either party to terminate upon day(s)written notice to the other party. 6. Should manifests or shipping forms be required by law or Laidlaw to accompany the Special Waste prior to disposal the Customer is responsible for preparing all such manifests or forms as may be required. 7. Laidlaw shall perform this agreement as an independent contractor,and will have and maintain complete control over all of its employee's,agents,and operations. 8. Laidlaw shall be entitled from Customer all reasonable attorney's fees,collection fees and costs for any action brought to enforce this Agreement. Laidlaw Waste Systems Inc. Customer Name: Di'�sion: (Customs') (Lrwew) Signature: Signature: Title: Title: Date: Date: LAIDLAW WASTE SYSTEMS INC. Continental Region WHITE-Laidlaw Copy YELLOW- Customer Copy (p_ ATTACHMENT IV TRANSPORTATION FORM Use this 3-part form for the hauler of the special waste to ensure acceptance at the landfill facility. A full set of approved documents should be attached. Upon acceptance at landfill facility, driver retains bottom copy, and original and one copy is retained at gate. Gate keeper to forward original to Account Executive to complete records. Generator: SWAA No.: Division No.: Region: Account Executive: Phone: Description of Waste: l will transport the above waste to (Hauler) (Facility Name) on . A full set of documents have been attached to this form for further (Date) information. The following signatures indicates transport has been completed. Signed: Date: Name of hauler Received by: Date: Facility gate keeper LAIDLAW WASTE SYSTEMS INC. Continental Region TOP- Account Executive Copy MIDDLE-Landfill Copy YELLOW- Transporter/Customer Copy ?n{e1s� ATTACHMENT V SPECIAL WASTE NOTIFICATION FORM t. FORM #1 LAIDLAW WASTE SYSTEMS, INC CONTINENTAL REGION SPECIAL WASTE NOTIFICATION REPORT lnsuuctions: This#onmiste be filled out for any problems associated with hauling of special wastes. If you have a spill involving special wastes,contact your dispatcher immediately. 1) Completely lilt out this form as soon as is possible following incident,' 2) Be complete and honest with reported problems. 3) Turn in this form to your dispatcher at the end of your workday. Date Time of incident AM or PM Generator: Incident reported: Driver's Signature Date Below to be completed by Division Manager Action taken: DM Signature Date Resolved: Rev 01 3/91 gC±, Golder Associates Inc. CONSULTING ENGINEERS SUBSIDENCE EVALUATION DENVER REGIONAL LANDFILL (SOUTH) Prepared for: Laidlaw Waste Systems, Inc. 2340 South Arlington Heights Road Suite 230 Arlington Heights, Illinois 60005 Prepared by: Golder Associates Inc. 200 Union Boulevard, Suite 100 Lakewood, Colorado 80228 with SubTerra, Inc. 5106 272nd Ave. N.E. Redmond, Washington 98053 and Doty & Associates 20011 Golden Gate Canyon Road, Suite 100 Golden, Colorado 80403 Distribution: 5 Copies - Laidlaw Waste Systems, Inc., Arlington Heights, Illinois 2 Copies - Golder Associates Inc., Lakewood, Colorado 1 Copy - Doty & Associates, Golden, Colorado 1 Copy - SubTerra Inc., Redmond, Washington September 1991 903-2284 as-_a „ GOLDER ASSOCIATES INC. •200 UNION ROUL FVARD.SUITE 100.LAKEWOOD(DENVER).COLORADO.U.S.A_80228•TEL(303)980-0500•FAX 1303)985-2080 OFFICES IN UNITED STALES•CANADA•UNITED KINGDOM •SWEDEN•GERMANY•ITALY•AUSTRALIA Subsidence Evaluation September 1991 i 903-2284 TABLE OF CONTENTS Paee 1.0 INTRODUCTION 1-1 1.1 Approach 1-1 1.2 Results of Field Investigation 1-2 2.0 SUMMARY OF AVAILABLE DATA 2-1 2.1 Mine Data Summary 2-1 2.1.1 Mine Layout 2-1 2.1.2 Mining Method and Production Estimates 2-1 2.1.3 Seam Depth, Dip and Strike 2-2 2.1.4 Seam Height and Extracted Coal Height 2-3 2.2 Geologic Sequence And Physical Characteristics 2-3 2.2.1 Coal Strength Data 2-4 2.2.2 Roof and Floor Rock Strength Data 2-4 2.3 Local Subsidence Events 2-5 3.0 GROUND FAILURE MECHANISMS AND ANALYSIS METHODS 3-1 3.1 Pillar Stability/Failure 3-1 3.2 Floor Stability/Failure 3-2 3.3 Roof Stability/Failure 3-3 4.0 RESULTS OF THE STABILITY ANALYSES 4-1 4.1 Pillar Stability 4-1 4.2 Floor Stability 4-1 4.3 Roof Stability 4-2 5.0 INTERPRETATION OF RESULTS 5-1 5.1 Potential For Sinkhole Development 5-1 5.2 Potential For Trough Subsidence 5-1 5.2.1 Pillar Stability 5-1 5.2.2 Floor Stability 5-1 5.2.3 Roof Stability 5-1 5.3 Subsidence Prediction 5-2 Golder Associates :Cv33 Subsidence Evaluation September 1991 ii 903-2284 TABLE OF CONTENTS (Continued) PPaa g 5.3.1 Worst Case Scenario 5-2 5.3.2 Maximum Subsidence & Subsidence Profile 5-2 5.3.3 Maximum Strain& Strain Profile 5-3 6.0 SUMMARY 6-1 7.0 REFERENCES 6-1 LIST OF TABLES Table 1-1 Subsidence Boring Locations and Elevation Data Table 1-2 Sample Locations for Laboratory Strength Testing Table 2-1 Coal Strengths from Laboratory Tests on Core Table 4-1 Pillar Stability Analysis - Area of Low Extraction Table 4-2 Pillar Stability Analysis - Area of High Extraction Table 4-3 Floor Stability Analysis - Area of Low Extraction Table 4-4 Floor Stability Analysis - Area of High Extraction Table 4-5 Roof Stability Analysis LIST OF FIGURES Figure 3-1 Sinkholes and Depth of Mining Figure 4-1 Pillar Stability - Area of Low Extraction Figure 4-2 Pillar Stability— Area of High Extraction Figure 4-3 Floor Stability— Area of Low Extraction Figure 4-4 Floor Stability - Area of High Extraction Figure 4-5 Roof Stability Figure 5-1 Subsidence Prediction Figure 5-2 Predicted Subsidence Profile Figure 5-3 Strain Profile LIST OF PLATES Plate 1 Worst Case Subsidence Prediction Golder Associates eF-nenra ' ...e , v+sar _ SUBSIDENCE EVALUATION September 1991 1-1 903-2284 1.0 INTRODUCTION This report presents an evaluation of the potential for ground subsidence toward the underground workings beneath the Laidlaw Denver Regional Landfill (South). Coal was mined at the site from the Columbine Mine from 1920 to 1951, at a depth of approximately 280 feet below ground. The main hoisting mine shaft and associated foundations are currently present near the center of the property. The shaft was plugged in June and July, 1990, by the Colorado Mined Land Reclamation Division from its total depth (282.5 feet below ground) to forty feet below ground. An air shaft and decline are also present on site. Subsidence related surface damage can take the form of sinkholes (if the abandoned workings are relatively shallow) or gently sloping troughs resulting from pillar collapse or pillar punching into either the floor or roof. Although regional data were available that could be used to evaluate the potential for surface damage resulting from these mechanisms, a field investigation was undertaken to determine the relative state of collapse of the workings as well as the in-situ material strengths (Doty, 1991). This report presents the results of the field investigation and the analyses based thereon. Conclusions regarding the potential for and magnitude of expected surface movement are also presented. 1.1 Approach The prediction of surface subsidence requires an analysis of the relative stability of the mine roof, floor, and pillars. Required input for theseanalyses includes details of the layout and extent of the subsurface workings and properties of the coal and surrounding strata. The approach taken in this report therefore consists of: ► Evaluation of on-site drilling data (this Section); ► Collection and documentation of mining data required for stability analyses(Section 2.0); ► Stability analyses using both the on-site and published data to quantify settlement potential (Sections 3.0 and 4.0); and ► Prediction of maximum subsidence and subsidence and strain profiles in the vicinity of the landfill expansion (Section 5.0). Golder Associates t%r r nn SUBSIDENCE EVALUATION September 1991 1-2 903-2284 1.2 Results of Field Investigation As stated, a field investigation was undertaken to determine the relative state of collapse of the workings as well as the on-site material strengths. Four boreholes(S-1 through S-4) were drilled at the locations shown on Plate 1. Coordinates and elevations of the boreholes are given in Table 1-1. Drilling began at S-2 approximately 39 feet south and 20 feet west of the center of the concrete collar of the main shaft. The boring was located to intercept a main haulage drift in an area of low extraction approximately 40 feet from the main shaft. The intent of the boring was to evaluate whether the haulage drift was still open. The drilling history of and core recovered from S-2 suggest that the boring intercepted a pillar rather than the haulage drift. Evidence includes the following. ► Consistent drilling pressures were maintained and good core recovery was achieved through most of the No. 3 Coal. ► The thickness of the No. 3 Coal in S-2 (11.6 feet) is generally consistent with the thickness reported in CMLRD(1986), Spencer(1986)and Amuedo and Ivey(1975) all of which indicate a minable thickness of up to 12 feet. ► Both the roof and floor material in S-2 appeared to be intact, based on the widely spaced fracturing observed in the core. Borehole S-1 was drilled approximately 11.7 feet west of S-2 (10 feet to the northwest perpendicular to the axis of the haulage) in another attempt to intercept the haulage drift. The borehole log of S-1 indicates the No. 3 Coal thickness to be 10.5 feet. It is believed that S-1 also penetrated the No. 3 seam in a pillar because drilling pressures remained constant while drilling through the coal even though the return of drill cuttings to the ground surface periodically stopped. A third attempt was made to drill into the haulage drift. Borehole S-3 was collared approximately 11.7 feet east of S-2 (10 feet to the southeast perpendicular to the axis of the haulage drift) and it is believed that the haulage drift was penetrated. The reasons for this are as follows. Golder Associates eneNr• SUBSIDENCE EVALUATION September 1991 1-3 903-2284 ► Immediately above the mining horizon, the data suggest the presence of relatively solid roof material. Core recovery is excellent down to and including the uppermost 2.9 feet of the No. 3 coal (down to 285.7 feet below ground). ► Very little core-was recovered from the interval believed to be mined. Below the 2.9 feet of coal, the recovered core consisted of coal chips (1/16 to 1/8 of an inch in diameter) and clay (both of which are believed to be rubble) and slough. Good recovery was not achieved until 299.0 feet below ground(brownish black claystone) although intact rock likely is present somewhat shallower than this depth. The elevation of the mine floor was effectively obscured by poor recovery possibly associated with a rubble blocked bit. In addition, there was essentially no return of cuttings to the ground surface. However, drilling pressures remained constant in these intervals of poor recovery suggesting an absence of voids. These poor ground conditions are thought to result from drilling through a rubble filled subsurface opening. A fourth subsidence boring (S-4) was drilled along the northern boundary of the site, immediately west of the shop. S-4 was drilled to evaluate the state of collapse of the mine workings in an area of high extraction. It is believed that the boring penetrated collapsed mine workings for the following reasons. ► The roof material was so badly broken that fractures could not be logged and cuttings return to the surface was non-existent. In addition, core recovery was very poor from 277.5 ft to 287.3 ft below ground. ► Coal was recovered from 287.3 to 288.0 which is believed to be coal left in the roof that has converged with the floor. ► Beneath the coal, core recovery improved dramatically and it is believed that intact floor material was being penetrated. A correlation between the S-2 and S-4 borehole logs indicates that either 2.5 feet of bottom coal was left in the area of S-4 or all but 1 foot of roof coal was taken. Leaving the lower coal may well have been justified by the thickness of the overlying claystone bed. Alternatively, removing all but one foot of roof coal would have been justified in areas designated for secondary mining (i.e., not requiring long term support). In either case, full subsidence is apparent. Samples of the roof, No. 3 coal, and floor material from S-2, S-1, and S-3 were submitted to the laboratory for strength testing. Sample numbers and depths are presented in Table 1-2. Detailed core logs and laboratory test analyses are contained in Appendices D and I (respectively) of Doty (1991). Golder Associates Cr tC,19 SUBSIDENCE EVALUATION September 1991 2-1 903-2284 2.0 SUMMARY OF AVAILABLE DATA 2.1 Mine Data Summary 2.1.1 Mine Layout Copies of the mine plan obtained from the Colorado Mined Land Reclamation Division (CMLRD)show that the site is underlain by the workings of the Columbine No. 1 Mine, including two mine shafts and a rock slope. The mine was operational until 1951 when it was abandoned; the main shaft was subsequently back- filled with muck and later grouted as part of the CMLRD's abandoned mine hazards abatement program. There are three key elements of the layout important to surface subsidence evaluations: 1. The main and ventilation shafts and decline (area 1); 2. An area of relatively low extraction(ER < 40%)adjacent to the main and ventilation shafts (area 2); and 3. Production areas to the north and south of the main shaft area where conventional, advance room and pillar mining and retreat mining (pillar robbing) were carried out (area 3). 2.1.2 Mining Method and Production Estimates The Columbine mine utilized the room and pillar system of coal extraction. A description of this method has been provided by Cooper and Abernethy (1937, p.313). The coal is undercut by machine, shot down with permissible explosives, and screened and picked, but not washed. ...The average daily output is 1,500 tons and the maximum 1,840 tons. The total output in 1931 was 275,072 tons. Ten percent of the output is from advance workings. The term "advance workings" in the last sentence of the description quoted above refers to the conventional method of room and pillar mining where rooms are excavated leaving square or rectangular pillars to support the roof. The remainder of the coal (e.g., 90% of the 1931 production) was mined "on retreat". This secondary mining method involves driving entries in the pillars left behind during advance mining, and is Golder Associates ("flint-nal SUBSIDENCE EVALUATION September 1991 2-2 903-2284 termed retreat mining because the process begins at the farthest extent of the panel mined on advance and continues back toward the main or panel entries. Extraction ratios in excess of 70% can be achieved using this secondary method. A typical Colorado coalfield operation would proceed as follows. ► Additional roof support (e.g., timbers) is set around the pillar to be mined. ► A 10 to 14 foot wide entry is driven through the pillar using timber props for roof support. ► The timbered supports are removed on completion of the entry. This operation induced roof failure and the transfer of load away from subsequent pillar robbing operations. Ground subsidence would occur as a result of the combined effects of pillar collapse, floor heave, and roof failure. Under these conditions, 90% of the expected surface deformations could be expected to occur almost instantaneously (e.g., within days). 2.1.3 Seam Depth. Dip and Strike According to Abernethy and Cooper (1937, p.312), the Laramie Formation in the Columbine No. 1 Mine strikes northeast and dips at about three degrees to the southeast. This has been confirmed, on a regional basis, by Amuedo and Ivy (1975) who have noted that the dip of the basin is gently east-southeast through most of the area, and regional strike is approximately northnortheast. Site specific dip estimates(determined by this investigation from depths to laterally extensive marker beds encountered during drilling) are on the order of 1.5 degrees to the southeast. The seam can therefore be considered to be flat for stability calculation purposes. The depth of the coal seam at the Columbine No. 1 Mine is required input for the calculation of overburden stresses and for determining the potential for sinkhole development. Three data points have been established based on existing information. 1. According to mine records, the approximate elevation of the Columbine shaft collar is 5165 ft, and the depth to coal, in the shaft, is 300 ft (Cooper and Abernethy, 1937, p.312; Amuedo and Ivy, 1975). This provides a seam elevation of 4865 ft. Golder Associates SUBSIDENCE EVALUATION September 1991 2-3 903-2284 2. Notes on the mine maps retrieved from the CMLRD indicate that the coal seam elevation varies from 4882 to 4888 ft. 3. The results of the drilling program indicate a seam elevation of 4882 feet in the vicinity of boreholes S-1 through S-3. A seam elevation of 4870 feet has been assumed for stability calculations. 2.1.4 Seam Height and Extracted Coal Height According to Amuedo and Ivy(1975), seven coalbeds of minable thickness occur in the Laramie Formation; they are numbered in ascending order from oldest to youngest. At the Columbine Mine, coalbeds 3 and 4 coalesce to form one bed as much as 12 feet thick. Up to three feet of coal was left in the roof at the Columbine No. 1 Mine to enhance roof support(Cooper and Abernethy, 1937). This accounts for the discrepancy between the 10 to 12 feet seam thickness reported by Amuedo and Ivy (1975) and the extracted seam height of seven (7) feet reported by Cooper and Abernethy. An extracted seam height of seven (7) feet is also consistent with the generic information presented by CMLRD (1986) for the Boulder Coalfield and with the results of the boring program. 2.2 Geologic Sequence And Physical Characteristics As noted above, the Columbine mine workings were located in the No. 3 and 4 Coals of the Laramie Formation. This formation is composed of interbedded shales, claystones, sandy shales, coalbeds, and thin beds of sandstone. Several qualitative characteristics of the strata surrounding the Columbine mine workings have been reported by Amuedo and Ivy (1975), as follows. 1. Local coal miners who have worked in the Columbine mine report that while the roof-stone of the mine is prone to collapse; an ironstone layer 12 to 80 feet above the mine workings tends to stop further upward caving. 2. The floor of the Columbine mine was a soft shale or clay, and a "squeeze" on the pillars was sometimes relieved by a heave or rise of the adjacent mine floor. The qualitative information noted in item 2 is confirmed by Abernethy and Cooper(1937)in their description of floor rock samples taken for laboratory testing. They also noted that the coal mined from the Golder Associates s;:v rn?g SUBSIDENCE EVALUATION September 1991 2-4 903-2284 northernmost coalfield(presumably Weld County)could not be transported long distances as it slaked rapidly after mining. The corelogs from boreholes S-1 to S-4 indicate the presence of a 2 to 3 foot layer of claystone in the immediate roof. This layer is overlain by interbedded siltstone and sandstone with a competent layer of sandstone located approximately 10 feet above the immediate roof. The mine floor consists of approximately 5 to 7 feet of claystone underlain by 1 to 2 feet of coal. 2.2.1 Coal Strength Data Rock mass coal strengths have been reported by CMLRD (1986) to range from 470 to 575 psi with a mean of 520 psi. Tests on core samples from the on-site boring program indicate a corrected average test specimen strength of 2,415 psi and an average coal rock mass strength of 630 psi. These results, and the range in Coal Rock Mass Strength for input to stability analyses, are summarized in Table 2-1. 2.2.2 Roof and Floor Rock Strength Data Roof and floor rock strength data have been calculated by CMLRD by "back-analyzing"historical data. The tensile strength of the roof rock was calculated assuming that the immediate mine roof behaves as a beam fixed at both ends (additional details of the analysis methodare presented in Section 4.2). The resulting tensile strength of the roof strata was calculated to range from 50 to 125 psi (CMLRD, 1986, p.8-11) for immediate roof thicknesses of from 5 to 7.5 feet and 20 feet roof spans. There appears to be a mistake in the units used in CMLRD (1986) in the calculation; the actual back-calculated tensile strength for a 5 to 7.5 feet thick roof beam at failure should range from 10 to 15 psi. However, back analysis based on more reasonable immediate roof thicknesses of 1 to 3 feet suggests tensile strengths at failure from 70 to 200 psi. Two brazilian disc tensile tests performed on core retrieved from borehole S-1 resulted in tensile strengths of 90 and 350 psi. Minimum, most likely, and maximum tensile strengths selected for use in the roof failure analysis are respectively 70, 90, and 200 psi. Maximum, most likely, and minimum shear strengths, estimated from tensile and uniaxial strength test results, are respectively 150, 175, and 250 psi. Golder Associates ter►rn9 SUBSIDENCE EVALUATION September 1991 2-5 903-2284 floor rock mass shear strength was calculated in CMLRD (1986)by back-analyzing data from the Hi-Way mine. The range in shear strength for the claystone floor material is reported by CMLRD (1986) to be 105 to 143 psi for strata thicknesses from 3.4 to 9.8 feet. Consolidated Undrained (CU) triaxial tests were performed on core retrieved from beneath the No. 3 seam in borehole S-2. The results (shown in Appendix I of Doty, 1991)provide estimated maximum,most likely, and minimum shear strengths of 65, 70, and 80 psi for use in the bearing capacity analysis. 2.3 Local Subsidence Events Two instances of subsidence in the vicinity of the site are documented in Amuedo and Ivy (1975). 1. The first incident is reported to have occurred approximately 1200 feet to the southwest of the main shaft. The incident description (Amuedo and Ivy, 1975, Map No. 7361-5, No. 64) simply contains the notation "Subsidence has been reported in this area above Columbine mine". 2. The second incident is reported to have occurred just'east of the site, directly east of the main shaft. The incident description (Amuedo and Ivy, 1975, Map No. 7361-5, No. 65) states, "Reports indicate that during mining, large(1.5 ft wide) cracks appeared along road here due to subsidence in fields to north and south". The first incident in all likelihood documents subsidence over the area of the mine where pillars were robbed. The second incident is undoubtedly abnormal movement associated with a fault which strikes approximately north. Golder Associates C'nrn SUBSIDENCE EVALUATION September 1991 3-1 903-2284 3.0 GROUND FAILURE MECHANISMS AND ANALYSIS METHODS This section of the report presents the theory and application of stability formulae used in Section 4.0 for subsidence potential evaluation. 3.1 Pillar Stability/Failure Coal pillar stability is calculated assuming each pillar supports an area equivalent to its own area plus an area of roof spanning half the distance to the next pillar. The pillar load (or stress) is calculated using the following formula: PL = (OLxAT) / AP where, PL = Pillar load (lb/in2, or lb/ft2); OL = Overburden Pressure, (lb/in2, or lb/ft2) calculated by multiplying the overburden thickness (ft) by the overburden unit weight (1b/fP); AT = Total area supported by pillar (ff); and AP = Area of pillar (ft2). This equation can be re-written in terms of the extraction ratio: PL = OL / (1 - ER) where, ER = Extraction ratio ((AT - AP) / AT). Traditional pillar strength formulae account for the intact coal strength (determined in the laboratory) and the pillar aspect ratio. The following two methods are used in this report. The first method is that suggested by Baushinger, as described by Hustrulid(1976, p.129)and Peng(1978, p.188). PS = CRMS x (0.778 + 0.222(Wp/Hp)) Golder Associates rn+^rn SUBSIDENCE EVALUATION September 1991 3-2 903-2284 where, PS = Pillar Strength (lb/in2, or lb/ft2); CRMS =Coal Rock Mass Strength (1b/in2, or lb/ft2); Wp = Coal Pillar Width (ft); and Hp = Extracted Seam Height (ft). The second is that suggested by Hustrulid (1976). PS = CRMS x SQRT(Wp/Hp). The factor of safety (FS) is calculated from the ratio of pillar strength to pillar stress. The ranges in the value of FS required for stability have been suggested by Brady and Brown(1985) to be 1.3 to 1.9, and by Peng (1978) to be 1.5 to 2.0. 3.2 Floor Stability/Failure Floor stability/failure is a function of the ability of the floor rock to resist the shear forces associated with pillar punching into the floor. Pillar punching is analogous to bearing capacity failure of a foundation and is analyzed using traditional foundation design methods. Again, two solution methods are described. The first method is that suggested by Brady and Brown (1985). Qb = 1/2(GMA.Wp.NG.SG)+c.cot(PHI).Nq.Sq. + c.cot(PHI) where, Qb = Bearing Capacity (lb/in2, or lb/ft2); NG = 1.5 x (Nq - 1) x tan(PHI); Nq = entire" x tan2(PI/4 + P111/2); SG = 1.0 - 0.4(Wp / Lp); Sq = 1.0 + sin(PIII).(Wp / Lp); c = material cohesion (lb/in2, or lb/ft2); and PHI = material friction angle. The second method is that suggested Vesic (1969) as reported in CMLRD (1986). Qb = SS x Nc where, Golder Associates rinn?c2c} SUBSIDENCE EVALUATION September 1991 3-3 903-2284 SS = Shear Strength (lb/in2, or lb/ft2); Nc = 5.61 + 0.146(Wp/t) for Wp/t > 3.8; and t = thickness of floor strata (ft). The disturbing force is the vertical pillar load (PL) previously defined in 3.1. The factor of safety is the ratio of the two forces (Qb/PL). 3.3 Roof Stability/Failure The process of collapse over a mine opening involves loosening and relaxation of the horizontally bedded roof strata which induces tensile and shear stresses at the abutments. If these stresses exceed the material strengths, then failure will occur. This failure will progress up into the roof until a stable arch is formed or partial support is provided by the broken rock pile. An analysis of the bulking potential of roof strata typical of the Laramie Formation indicates that movement would be arrested a distance approximately equal to 5 to 6 times the extracted seam height. This hypothesis has been field verified as part of the work conducted by the CMLRD. They conclude that the probability of failure extending beyond ten times the extracted seam height is less than 5% and beyond fifteen times the extracted seam height the probability is almost zero (Figure 3-1). Roof stability/failure can be determined by analyzing the resisting and disturbing forces present in the roof strata immediately prior to failure. Assuming that the roof strata behaves as a simple beam, the maximum tensile stress occurs at the outer fiber at the center of the beam, with: TS = (3 x GMA x 12) / (4 x t) where, TS = Maximum Tensile Stress in Roof Beam (1b/ft2); GMA= Unit Weight of Roof Strata (lb/ft'); L = Roof Span (ft); and t = Thickness of Roof Beam (ft). The maximum shear stress occurs at both ends of the beam above the rib, with: SS = (3xGMAxL) / 4 where, Golder Associates 1119.1`,F29 SUBSIDENCE EVALUATION September 1991 3-4 903-2284 SS = Shear strength (lb/in2, or lb/ft2). In the case where lateral deformation is restrained and the roof can be considered to act as a beam clamped at both ends, the maximum tensile stress occurs at the upper side on both ends of the beam, with: TS = (GMA x L2) / (2 x t). The resisting forces are the tensile (ZIGt) and shear strengths (TOR)of the roof strata. The factor of safety is again expressed as the ratio between the two resisting and disturbing forces (ZIGt/TS) and (TOR/SS). ecr ,. Golder Associates ....�u, 4.1 SUBSIDENCE EVALUATION September 1991 4-1 903-2284 4.0 RESULTS OF THE STABILITY ANALYSES 4.1 Pillar Stability -Pillar stability analyses have been carried out to evaluate the stability of workings in the vicinity of the main and ventilation shafts (area 2 in Section 2.1.1) and in areas where secondary mining has been carried out (area 3 in Section 2.1.1). The results of these calculations are presented in Tables 4-1 and 4-2 and Figures 4-1 and 4-2. Table 4-1 shows the range in pillar safety factor for the area of low extraction based on the laboratory coal strength test results and proposed site layout. Figure 4-1 provides a cumulative probability curve for the pillar safety factor after completion of the cover system. This curve shows that the most likely post- completion safety factor is 2.15 and that there is 90% certainty that the post completion safety factor is greater than 1.9. Table 4-2 and Figure 4-2 provide corresponding results for the area of high extraction;however,in this case, the cumulative probability curve represents conditions prior to construction. It can be seen that the most likely pre-construction safety factor is 0.7 and that there is a 90% certainty that the safety factor is less than 0.83. 4.2 Floor Stability Floor stability analyses have been carried out to evaluate the potential for failure in both areas 2 and 3. The results of these calculations are presented in Tables 4-3 and 4-4 and Figures 4-3 and 4-4. Table 4-3 shows the range in floor stability safety factor for the area of low extraction based on the laboratory rock strength test results and proposed landfill layout. Figure 4-1 provides a cumulative probability curve for the floor stability safety factor prior to landfill construction. This curve shows that the most likely pre-construction safety factor is 0.90 and that there is 90% certainty that the pre-construction safety factor is not less than 0.8. Golder Associates SUBSIDENCE EVALUATION September 1991 4-2 903-2284 Table 4-4 and Figure 4-4 provide corresponding results for the area of high extraction. It can be seen that the most likely pre-construction safety factor is 0.4 and that there is a 90% certainty that the safety factor is less than 0.3. 4.3 Roof Stability Roof stability analyses have been carried out for opening widths typical of area 2(i.e., 12 feet). The results, for various roof stratum thickness, are presented in Table 4-5 and Figure 4-5. Table 4-5 shows the range in the tensile and shear roof stability safety factors for roof layer thicknesses of 2 to 5 feet. Figure 4-5 shows the cumulative probability curve for the tensile safety factor assuming a range in roof layer thickness of from 1 to 3 feet. This curve shows that for conditions representative of the Columbine mine roof, the most likely roof stability safety factor is 0.9. nocGolder Associates ... � tri SUBSIDENCE EVALUATION September 1991 5-1 -91)3-2284 5.0 INTERPRETATION OF RESULTS 3.1 Potential For Sinkhole Development The ratio of overburden thickness to extracted height for workings in the Columbine Mine is 300/12 = 25 (worst case), or 300/7 = 43 (based on reports of extracted seam thickness). The potential for sinkhole development is therefore considered improbable. 5.2 Potential For Trough Subsidence As previously noted in Section 3.0, the potential for trough subsidence or regional downwarping is governed Py the stability of the pillars, roof and floor. Vertical deformation is primarily associated with pillar failure and pillar punching while roof failure results in a zone of loosened rock which serves to progressively restrict deformation of the pillars and floor. 5.2.1 Pillar Stability Based on the analysis results presented in Table 4-1,pillars in area 2 have an estimated minimum safety factor of approximately 2.0, indicating stability. Small, remnant pillars in area 3, where secondary mining has been carried out, will have collapsed. As noted in Section 2, these results have been confirmed by borings in area 2 (S-1 through S-3) and area 3 (S-4). 5.2.2 Floor Stability Analysis results contained in Tables 4-3 and 4-4 indicate that pillar punching is likely to have occurred throughout the mine. The corelog from borehole S-3 located adjacent to the main shaft also indicates that a significant part of this deformation is complete. 5.2.3 Roof Stability Field investigation and laboratory test results indicate that the immediate roof in the Columbine Mine is prone to collapse at roof spans characteristic of area 3. This condition would have been further worsened Golder Associates fy-;or e) SUBSIDENCE EVALUATION September 1-991 5-2 993-2284 by tensile stresses exerted in the mine roof as a sesult of adjacent pillar-robbing during secondary mining operations. In area 2, instabilities in the mine roof during mine operation were probably confined to minor falls since, consistent with standard practice, the narrower mined width (12 feet) was chosen to enhance -operational stability. However, more widespread failure is likely to have developed since abandonment. It is believed that failure will have occurred up to a depth of approximately 10 feet into the roof where a relatively competent sandstone is located. 5.3 Subsidence Prediction 5.3.1 Worst Case Scenario The analyses (Section 4) and interpretations (Section 5) presented above confirm that a majority of the potential subsidence above the Columbine Mine has already taken place. Nevertheless, it is prudent to -examine the worst case hypothesis that subsidence may still occur over area 2, the area of low extraction. The hypothetical worst case scenario is illustrated in Figure 5-1. In accordance with the analyses conducted, surface lowering is assumed to be associated with pillar punching; no prior deformation is assumed to have occurred. 5.3.2 Maximum Subsidence & Subsidence Profile Dilation of the rock mass will occur during failure resulting in a reduction in the magnitude of subsurface vertical displacements transmitted to the surface. A reduction factor of 20% is typically accepted for single seam workings based on European experience while factorsas high as 40% have been reported domestically. There is also evidence(S-4 corelog)that the shale/claystone parting between the upper and lower coal seams may have been disposed of underground as backfill. However, in line with the spirit of the worst case scenario, the reduction factor has been set at 0% and a maximum subsidence of 2 feet has been calculated using the following parameter values: Smallest pillar size in area (2) of 40 ft by 40 ft, hence, Wp = 40 ft., Room width (Wr) of 12 ft, and Extracted height (Hp) of 7 ft. fl-older Associates ine-:nor„, SUBSIDENCE EVALUATION September 1991 5-3 903-2284 The worst case scenario subsidence profile-has been estimated using the profile function contained in the Subsidence Engineers-Handbook(NCB, 1975, page 13) for a width to depth ratio of greater than 1.4 (i.e., supercritical width). Note that the ribside on the NCB's nomogram coincides with the boundary between area 2 and area 3. figure 5-2 shows the estimated subsidence profile and Plate 1 shows subsidence contours relative to the boundary between area2and area). The maximum slope associated with the worst case subsidence profile is estimated to be 1.6%. 5.3.3 Maximum Strain& Strain Profile Induced ground strains, which are primarily a function of the shape of the subsidence profile, have been estimated from Figure 13 on page 29 of the Subsidence Engineers handbook (NCB, 1975). From the nomogram: Maximum Extension = 0.65 x (2/300) = + 0.-004 in/in; and Maximum Compression = 0.60 x (2/300) = - 0.004 in/in. The corresponding profile has been estimated using the nomogram on page-25 of the Subsidence Engineers handbook (NCB, 1975) and is shown in Figure 3-3. Note that the point of maximum extension for supercritical width(+E) on the NCB's nomogram coincides with the boundary between area 2 and area). _Golder Associates +*F:Cr?9 Subsidence Evaluation September 1991 6-1 903-2284 6.0 SUMMARY The stability analyses presented above, in conjunction with the Eeld investigation program, confirm that subsidence is substantially complete in the area where secondary mining orpillar robbing has been carried out. Settlement predictions have been made,based on a-hypothetical worst case scenario, to estimate the potential magnitude of future surface deformations above the border between area 2 and area 3. A worst ease maximum subsidence of two (2) feet, maximum slope of 1.6% and maximum ground strains (both tensile and compressive) of 0.4% have been estimated for input to the design. It must be stressedthat the worst case scenario evaluated above is extremely conservative because it is-based on the following assumptions. ► No movement has occurred in the 40 years since abandonment. This is inconsistent with the conclusion of CMLRD (1986) which states on page 13-2, "the borehole data suggest that less than 10% of the total under-mined area investigated has some remaining void", and on page 8-34, "..approximately 90 percent of all subsidence events occurred within 10 to 40 years after the completion of mining." ► 100% of vertical subsurface displacement will betransmitted to the surface. Again, this is inconsistent with results in other coalfields which indicate a reduction of from 20 to 40%. Two abandoned mine access shafts and a decline have been identified as potentially impacting the development of the site. The main shaft has been backgrouted by CMLRD to a depth of 40 feet below surface and should pose noproblem for site development. Closure/reclamation designs for the air shaft and decline are presented in the design and operations plan. GOLDER ASSOCIATES INC. David L. 0'Sadnick, P.E. Chris D. Breeds, Ph.D. Associate _President Golder Associates Inc. SubTerra Inc. -Golder Associates SUBSIDENCE EVALUATION September 1991 7-1 903-2284 7.0 REFERENCES Amuedo and Ivey, 1975. Ground Subsidence and Land Use Considerations Over Coal Mines in the Boulder-Weld Coalfields. Colorado. Amuedo and Ivey Geological Consultants,Colorado Geological Survey, Environmental Geology No. 9. Brady, B.H.G., and-Brown, E.T., 1985. Rock Mechanics for-Underground Mining. Published by George Allenand Unwin, Winchester, Massachussets,327 p. Brown, ED., and Meyerhof, G.G., 1969. Experimental Study of the Bearing Capacity in Layered Clays. Proc.Seventh-International Conference Soil MechanicsandFoundation Engineering,lvlexico City, Vol.2, pp.-5i1. Chandrashekhar, K., Nath, R., and Tandon, S., 1987. Design of Coal -Pillars Under Weak Floor Conditions. 28th US Symposium onRock Mechanics, Tucson, Arizona, pp. 1072-1081. CMLRD, 1986.Boulder County Subsidence Investigation. Final Report, Colorado Mined Land Reclamation Division. Cooper, H.M., and Abernethy, R.F., 1937. Analysis of Colorado Coals. US Department of the Interior, Bureau of Mines, Technical Paper 574. Doty, 1991. Site Characterization,Denver Regional Landfill (Southl, prepared for Laidlaw Waste Systems, Inc.,Ioty & Associates Project No. 1202-05, September 4, 1991. Hustrulid, 1976. A Review of Coal Pillar Strength Formulas. hock Mechanics, V. 8. Vesic, A.S., 1970. Research on Bearing Capacity of Soil. (unpublished: reported inChandrashekhar et al., 1987) ng Golder Associates Table 1-1 SUBSIDENCEMORING LOCATIONS ANDjMELLEV`ATIONDATyA %`n .. ...KY th�,n /yy�K'��`}Yt.3SIO £ 3 ) = L-F 'A� 'r/�3.� . q V l lluL ' a a 'bo-X O RDI ALES Et:gVATtQ j e is aOREir£?.i 5P fltt Tkit1G. A E1t1Ca ; Fa :fl 1tY. . I :: .,,. . -S-1* 8438.20 12613.27 5163.91 320.00 S-2 -843645 1262489 5164.51 324.00 S-3 843477 12636.42 5165.42 321.50 S-4 -9932.54 12933.35 5177.40 334U0 Notes: Coordinatesand-elevations(feet NGVD)provided by Contract Surveyors, Ltd. * Coordinates of S-1 are astimated. September 1991 903 2284 Golder-Associates r - nc� Table 1-2 SAMPlf LOCATIONS FOR LABORATORY STRENGTH-TESTING MINE' TE$T $ . ys £ . . SAMPLE\hl< I sk FF:ir1TDRE . ..TYPE* BORING NUMBER k o-,I ATER1XL,tt :.; DEPTH(Fl) Roof Brazilian S-1 2 Claystone 274.9 - 275.9 Brazilian S-1 3 Claystone 280.2 — 280.8 UL S2 5 Claystone 2791 — 280.9 UU S2 1 Siltstone 280.3 - 281.0 Coal UU S-1 4 Coal 283.6 - 284.4 UIJ S-.2 7 Coal 283.9 - 285.3 UU S-3 2 Coal 286.5 - 287.3 Floor CU 5-1 8 Claystone 293.7 - 294.7 CU 5-2 9 Claystone 296.0 - 297.D CU S-3 3 Claystone 299.5 - 301.2 September 1991 903-2284 Golder Associates rrinrl2q Table 2-1 COAL STRENGTHS FROM LABORATORY TESTS ON CORE INEERIBIEMIIIIIMIAM BROMEINIIINillIIIIIIIIIIIIIIIIIIIIMINIIIIIII wowLO�.{iTOE�a L Q ; s 1 Lph i amen Ezgoani g¢ Coal 283.6-284.4 4.524 2.396 1W80 2457 2744 Coal 283.6-284.4 1.985 2.392 10700 2381 2277 Coal 283.9-285.3 2.534 2.409 10760 2361 2387 Coal 283.9-285.3 5.195 2.406 7100 1562 1773 Coal 286.5-287.3 1.811 2.498 12920 2636 2431 Coal 286.5-287.3 4.278 2.403 11770 2595 2875 2.417 2415 COpI 5trectgtp P)Nar ii40 . ..:... . . .__ 743 max 626 avg 458 min September 1991 903-2284 Golder-Associates r FTn...,, Table 4-1 PILLAR STABILITY ANALYSIS AREA OF LOW EXTRACTION Equation: PS = CRMS x (0.778 +0.222 x (W/H)) Seam Elevation: 4870 ft Ground Elevation: 5200 ft Floor Elevation: 5100 ft Waste Elevation: 5340 ft E.fttac k. Coai P►Itat ra zFllfter s F RAt1U $tterigtil f 5ttetiiii SE Beffits `` SF life Qyn �s Wa5t8 F f li {)Wlt}r ' E .R.MS (PSG €EJscBXattort :ttaitlttRrE i `..ErripiaSSSYtatit 35 460 1087 2.14 3.07 1.86 35 630 1489 2.93 4.21 2.55 35 740 1749 3.45 4;94 2.99 40 460 971 1.76 2:53 1.53 40 630 1329 2.42 3.47 2.1-0 40 740 1561 2.84 4:07 2.47 September 1991 903-2284 Golder Associates r.�n,r- ti Table 4-2 PILLAR STABILITY ANALYSIS AREA OF HIGH EXTRACTION Equation: PS = CRMS x(0.778 + 0.222 x (W/H)) Seam Elevation: 4870 ft Ground Elevation: 5200 ft Floor Elevation: 5100 ft Waste Elevation: 5340 ft Erctt#4 Coaiy ' Pfl[ar ' , �r> apt - SRAfteT Remit strength Strength sF Before S:FA 1"f wapte (ERt) "(C MSS ..:{PS) ..:,.:ExcaVadtrrt axca y .b:' tmpiataient 60 -460 650 0.79 1.13 0.68 60 630 890 1.08 1.55 0.94 60 740 1045 1.27 1.82 1.10 70 460 577 0.32 0.75 0.46 70 630 790 0.72 1.03 0.62 70 740 928 0.84 1.21 0.73 80 460 504 0.31 0.44 0.27 80 630 690 0.42 0.60 0.36 80 740 810 0.49 0.70 0.43 September 1991 903-2284 Golder Associates t'•^nr7 Table 4-3 FLOOR STABILITY ANALYSIS AREA OF LOW EXTRACTION Equation: Qb =SS x (5.61 +(0.146 x(WpfT))) Seam Elevation: 4870 ft Ground Elevation: 5200 ft Floor Elevation: 511O0 ft Waste Elevation: 5340 ft i>:c•J:c•:(.:iJ::J:•/o'c•:' :.`•.:::•.:• o≥c:::o5:2�`:�' ::.°�:?:#33:: �o:`::;:::c:': ��,.yr�y y}� .,-.k .y :::%.,.... }:..0:1'r:i:`.J>�.•>r`;:" .f-n• ::.Sr:•}:i'; ..h::.:.:r•:. >:r� ,:! vrl:yr-J ::�:}.::!.:•jjv�tiEtiv'ti(::S:1-Jv��`�..O.}}..}.-.}Svli,'.r v...0i.i:!ti l••'•-��%.v;}•4 CJ:.J':C...........ry r.,is�: 4�J:: JJ:((?^J::4J:^JJ;(!r,-:C:•::fr:r+?'iJ...2.h...r .n4v.w -.:%r:`V:r rn l.n}.v... .;Qi- Q::-..:i:•, r\lrvrn}•n%.%:'.A:J:4�:.....„ ::�l�:Q��:}:,:.;::}:•'':l:' v nrJ'�r vrr:ly::. r��'i:'-}•:• ,}}�.. .).. 3f.:. �y•:.?.::..:.(.:i''('i:AY:GJ;�:<Ji'v�r'�%J,.;..•}".(.. :\.(. ,� ,�„ ,aio::r•:•:•o:.,;r!:!:,::;:;�.;�$:: :; •i:i ;o-F::.x�Jy ,•.,2•.:opep. y. :J:" F{yam S' ryt.uy. •.,r:7�: •2J,:J:2i::Y4,}: :;n:!•ry :o1011t :;:•:!:i:::, l31. 61 11:#r••:�:;FS:SE"10..,r. :5•,''P:�S.....fif :?:'-:'!::•.nn}4-•::. :',Itt� Q(:c:."^ ...;,..;,.',.j: ::•:Q ::F.•:•`•-:i•TF.•0::.•:v'i.:v..:.:.:..:.,:..:...::v...... .r.«:}h.}v.w..... ...�::0�'i:::b} r•J.:-.h.r....:.. 2• •:N�' G:!7.4i:1.%ri((.r :+rhr'vri4%G[:ii]Y:9n:b h•�iOgRefl:J}%\2�} .�.:J..... ..�:?,. . f J .iriY.•:8j:`• .....�..'.//:ll!:^::2:':•'rrri ::.S:.. .:.!..;!:n::::r.:....�` :•:6c:: '}:u:...... <ra.?^.::,: ..r•;�S't��i:r.;:<o.:o:.::.,o•..S•,.,• "A::.•9.••. 35 65 444 0.87 1.25 0.76 35 70 478 -034 1.35 0.82 35 80 546 1.08 1.54 0.93 40 65 431 0.78 1.12 0.68 40 70 _464 -084 1.21 0.73 40 80 531 0.J6 1.38 0.84 September 1-991 903-2284 Golder Associates ",.-,Cr,a Table 4-4 O STY S AREAFLO R OF HIGHABILIT EXTRACTION Equation: Qb = SS x (5.61 +(0.146 x(Wp/T))) Seam_Elevation: 4870 ft Ground Elevation: 5200 ft Floor-Elevation: 5100 ft Wastealevation: 5340 ft Rltltl 5 Shear c Qapac4ty air$F Before r e SFAfen"v f a W9ate n en (. I eagt to)". �YEaccaltatiart�s. E`fccaUtt iralp)BCemd t. ER .,:. .str ft T :.M . 60 65 396 0.48 0M9 0.42 0.52 60 70 427 0.7-4 0.45 60 80 488 0.59 0.85 0.51 70 65 388 0.35 0.51 0.31 70 70 418 0.38 0.55 0.33 70 80 -478 0.43 0.62 0.38 80 65 380 0.23 0.33 0.20 80 70 410 0.25 0.36 0.22 80 80 468 0.28 0.41 0.25 September 1991 903-2284 Golder Associates t:( ,�r,�9 v Table 4-5 ROOF STABILITY ANALYSIS Equation: FS =TS/((GMA x Wr'2)/(2 x t)) Seam Elevation: 4870 ft Ground Elevation: 5200 ft Floor Elevation: 5100 ft Waste Elevation: 5340 ft NMmama iiiiiPOSIIII:110.1101 Tertsile < z z S F Shear Layer pat or "< Factor 1 suengttl z q*NMI"a�AN 'Tltic�ly less ti bit irf a 'iri SneatC ::;$0000001-4i. Plii4e )5. fj N(SS s5c .. tiim<e: :.: �� J:.(FS) .y ,<EJ (FS) q... 70 150 2.0 0.47 10.07 90 175 2.0 0.6 11.75 200 250 2.0 1.34 16.78 70 150 3.0 0.7 10.07 9D 175 3.0 0.91 11.75 200 250 3.0 2.01 16.78 70 150 4.0 0.94 10.07 90 175 4.0 1:21 11.75 200 250 4.0 2.69 16.78 70 150 5.0 1.17 10.07 90 175 5.0 1.51 11.75 200 250 5.0 3.36 16.78 September 1991 903-2284 Golder Associates rr O11.,?9 a z T Z co C z W LL 9 0 '' I -c a --, Ui w o- O 4) C CD - � z g Q 3 -O 0 C — r) w O J 0 V) in — N I O 3 Z_/� r W V/ S 0 c i. 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O c O 3 N z W a` n 9 b Q0 I 0i- rD z a wM J u CC O U CC Lij II F > W z w g LLI O � W ; 9211/639 i ifAffeffAff Air LA DLAW WASTE SYSTEVS , I \ C . JE_\ V= =GIC \ AL LA\ DF LL ( SO T- ) SITE CHARACTERIZATION DENVER REGIONAL LANDFILL ( SOU VOLUME II September 23, 1991 Prepared by: Doty & Associates 20011 Golden Gate Canyon Road Golden, Colorado 80215 92:C639 DOTY & ASSOCIATES ENVIRONMENTAL,GROUND-WATER AND WASTE MANAGEMENT ENGINEERS 20011 GOLDEN GATE CANYON ROAD SUITE 100 GOLDEN, COLORADO 80403-8125 TELEPHONE: (303) 279-9181 FAX: (303)279-9186 SITE CHARACTERIZATION DENVER REGIONAL LANDFILL (SOUTH) September 23, 1991 VOLUME II Prepared for: Laidlaw Waste Systems, Inc. 2340 South Arlington Heights Road Suite 230 Arlington Heights, Illinois 60005 Prepared by: Doty & Associates 20011 Golden Gate Canyon Road Suite 100 Golden, Colorado 80403 a a with 0 v Golder Associates Inc. L 200 Union Boulevard Suite 100 o Lakewood, Colorado 80228 Project No. 1202-05 920633 APPENDIX G PACKER TESTS a a u u 0 co V w c 0. 9C633 Laidlaw Denver Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates PACKER TESTING Packer tests were -performed in six of the borings during this investigation, using methods described in Appendix C. The resulting data were analyzed using the technique described below. The results and all data are presented following the description of the analytical technique. The formula for calculating hydraulic conductivity from packer test data is: Q L K = In (---) 2 (PI) (L) (H) r where K = Hydraulic conductivity (feet/min) , Q = Injection rate (feet3/min) , L = Length of test section (feet) , H = Differential head of water (feet) = distance from the water table to the gage plus gage pressure for test intervals below the water table. = distance from the center of the test interval to the gage plus gage pressure for test intervals above the water table, r = radius of borehole (feet) , In = natural logarithm, and PI = 3 . 141592 . The packer test results for each injection pressure are presented on Table G-1, together with a best estimate result for the test. In addition, a geometric mean of the tests considered to be a reliable for each material is presented. In calculating these material means, the following tests were -excluded: Boring Depth (feet) Reason for Rejection 0 S-4 50. 00-62 . 04 packers leaked S-203 33 . 45-44 .76 intensely fractured S-209 60. 61-71. 92 packers leaked S-209 57 . 29-68 . 60 packers leaked S-4 82 .4-94 . 28 packers leaked S-203 69 . 85-81. 16 sandstone very thin G-1 920633 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates 0 ., 0 "— A .O N in 04.00 O O m y 1- 1.1 E L P 0 N Oca co d - .O M W z N W C4J ANNA.OA.ONN ..TNWCOA Y)NN.T. NNN.ON N M C0 O q ai +i — N O O N N O N O N O N N d O N O O O O N OV OI•,. • • • •.OMMNN • • • • • .OANOJ NO AN M L CO Nerrr NM•O NNMJ.t NNNr • • • • • cNNNMN O 0 W4- f— M AIO.OAdA.O . . NN.ONA ANN . u . . .Ovf N N O O N N N O W O O N O O O N O at, ‘ rAMMMNN 0..0AON N•O.T on NM. W N.-.OrrNM rr rN•O •—.}N N NM r NE a ON ANNA.O A• .4 • QNd CO.0 CONN . N . .f.ON T N O O O N O O N 0 & ‘ 4, N N N Cl ' N O .ONMCOM.OAN N—NMEO .1A0 .O NN N A.O,-.rrr t' NN.OAr ANN A NCO, OC r W r ANJnA•OA.0.0N NN.000A NNNN NNN.O.O U O O L O N N O N O L O N O O 0 0 0 0 N N N N N U 0..O-r.1 P_OMN rN0NO CO P.ON NNOrP PNTrrr.000.O NNNNr NM.-w- NNNN.O O. N N M D N U N N N \ N O N U\ 0 CD F-0- K \ -,I01 e U N N N N N N N H U\ \00 \\ \ N \ 0,0U UJ.06 • reel-. \\ 00 `.... •000 L O O D U C N 4? N N N N N N N N N U U \\ Y \\\\.— 00 \\\ \\\1—H ON 0 00100CANCACI)VI 000141 —I WON in Col NW -J—I X 00000000 0 0 0 0 U N U U U U 0 0 1.1N N 0. ..pp .p .p N 41 O ggES O M .0OA In in.0 Cs NNNN.O •-•-.0 'O.O P.00 y y y y u O. N CONNWOCONr4p0p .442 NOW 0.0.r NCOMIN.O �l2f0 U L W N.O*4 in in P NA•O PW�^P CO..•-•• P0.O W N q .m...• N.1 L L JEEU N N late 0. N Npp O 11 11 11 O N OOL .O O NNNNf�.ON NNPN.O COA N.PO N N.O.O.O C WOMAG.AIry01. CVNO0..0 pt-corn MANON C r NNM.tM0MC10 NArr .OMON Copp,'" NN -N (;J r r r •• 000e V1 e L N M NN CO COPP NM CO MP O.N PPM N O. O 0000000 000 0 FIR 0 000 ,N, 1.1•N N N N N N N N NNN M N N N N N N N M N 0 m r N N N N N N 0010 N 0 W N W 04100N NNN N 2 G-2 92"0633 Laidlaw Denver Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-3 Test Date: 5/14/91 Hole Diameter: 5. 875 inches Depth Interval From: 86. 62 feet To: 98 . 66 feet Static Depth to Ground Water: 262 . 16 feet Height of Gage Above Ground: 6. 08 feet Inside Diameter of Manometer: 2 inches Interval #1 First Manometer Tape Reading: 30 inches Test #1 Initial Height of Water Above Gage: 4 . 06 feet Packer Inflation Pressure: 114 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 . 00 - 1 : 42 .50 1. 4e-7 3 : 35 . 50 1.2e-7 5 : 45 .50 l. le-7 8 : 7 .50 9 .8e-8 10 : 41 . 50 9 . 0e-8 13 : 28 . 50 8 . 3e-8 16 : 36 .50 7 . 4e-8 Geometric Mean 1. 0e-7 Interval #1 First Manometer Tape Reading: 35 inches $ Test #2 Initial Height of Water Above Gage: 3 . 643 feet E (1st) Packer Inflation Pressure: 114 psi Gage Pressure: 15 psi T Elapsed Manometer Hydraulic 0 Time Drop Conductivity Min :sec (inches) (cm/s) 0. 0 : 0 . 00 0 : 15 5. 00 7. 1e-6 0 : 26 5. 00 9 . 7e-6 0 : 38 5. 00 8 .9e-6 0 : 49 5. 00 9 .7e-6 1 : 0 5. 00 9 . 7e-6 Geometric Mean 9 . 0e-6 G-3 9 W£t a'9 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-3 Test Date: 5/14/91 Interval #1 First Manometer Tape Reading: 30 inches Test #2 Initial Height of Water Above Gage: 4 . 06 feet (2nd) Packer Inflation Pressure: 114 psi Gage Pressure: 15 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 . 00 - 0 : 42 5. 00 2 . 5e-6 1 : 22 5. 00 2 . 7e-6 2 : 7 5. 00 2 .4e-6 2 : 52 5. 00 2 . 4e-6 3 : 40 5. 00 2 .2e-6 4 : 26 5. 00 2 . 3e-6 Geometric Mean 2 . 4e-6 Interval #1 First Manometer Tape Reading: 32 inches Test #2 Initial Height of Water Above Gage: 3 . 893 feet (3rd) Packer Inflation Pressure: 114 psi Gage Pressure: 15 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min : Sec (inches) (cm/s) a 0 : 0 . 00 - 1 : 5 5. 00 1. 6e-6 E 1 : 57 5. 00 2 . 1e-6 2 : 56 5. 00 1. 8e-6 L 3 : 57 5. 00 1. 8e-6 0 4 : 57 5. 00 1. 8e-6 E 6 : 0 5. 00 1. 7e-6 c a Geometric Mean 1. 8e-6 G-4 Si'V S 3S laidlaw Denver Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-3 Test Date: 5/14/91 Interval #1 First Manometer Tape Reading: 34 inches Test #3 Initial Height of Water Above Gage: 3 .727 feet Packer Inflation Pressure: 120 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) O : 0 . 00 - O : 18 .50 7.7e-7 O : 36 . 50 7 .7e-7 0 : 52 .50 8.7e-7 1 : 9 .50 8 .2e-7 1 : 26 . 50 8 . 2e-7 1 : 42 .50 8 .7e-7 2 : 17 1. 00 8 . oe-7 2 : 51 1. 00 8 . 2e-7 3 : 28 1. 00 8 . 0e-7 3 : 59 1. 00 8 .5e-7 4 : 32 1. 00 8 . 5e-7 5 : 7 1.00 8 . 0e-7 5 : 45 1. 00 7 .4e-7 6 : 25 1.00 7 . 0e-7 7 : 9 1. 00 6.4e-7 7 : 58 1. 00 5.7e-7 8 : 52 1. 00 5 . 2e-7 10 : D 1. 00 4 . 1e-7 11 : 19 1. 00 3 . 6e-7 k 13 : 2 1. 00 2 . 7e-7 15 : 16 1. 00 2 . 1e-7 a 0 Geometric Mean 6. 4e-7 0 c 0 a 0 w c L a G-5 9:LCS33 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-3 Test Date: 5/14/91 Bole Diameter: 5.875 inches Depth Interval From: 70. 62 feet To: 82 . 66 feet Static Depth to Ground Water: 262 . 16 feet Height of Gage Above Ground: 6. 08 feet Inside Diameter of Manometer: 2 inches Interval #2 First Manometer Tape Reading: 12 inches Test #1 Initial Height of Water Above Gage: 5. 560 feet (1st) Packer Inflation Pressure: 120 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) O : 0 . 00 - O : 24 4 . 00 5.4e-6 O : 50 4 . 00 5. 0e-6 1 28 5. 00 4 . 3e-6 2 : 13 5. 00 3 . 6e-6 2 : 55 5. 00 3 .9e-6 3 : 34 5. 00 4 . 2e-6 4 : 16 5. 00 4 . 0e-6 5 : 2 5. 00 3 . 6e-6 5 : 53 5. 00 3 . 3e-6 6 : 48 5. 00 3 . 1e-6 7 : 47 5. 00 2 .9e-6 Geometric Mean 3 . 9e-6 a v v G-6 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-3 Test Date: 5/14/91 Interval #2 First Manometer Tape Reading: 5 inches Test #1 Initial Height of Water Above Gage: 6. 143 feet (2nd) Packer Inflation Pressure: 120 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 .00 - 0 : 59 5. 00 2 .7e-6 2 : 3 5. 00 2 . 5e-6 3 : 15 5. 00 2 . 3e-6 4 : 27 5. 00 2 . 3e-6 5 : 44 5. 00 2 . 1e-6 7 : 2 5. 00 2 . 1e-6 8 : 24 5. 00 2 . 0e-6 9 : 54 5.00 1. 8e-6 11 : 28 5. 00 1.8e-6 13 : 3 5.00 1. 8e-6 14 : 39 5. 00 1.8e-6 Geometric Mean 2 . 1e-6 Interval #2 First Manometer Tape Reading: 45 inches Test #2 Initial Height of Water Above Gage: 2 . 810 feet (1st) Packer Inflation Pressure: 120 psi Gage Pressure: 12 psi k Elapsed Manometer Hydraulic a Time Drop Conductivity E Min :Sec (inches) (cm/s) u u 0 : 0 . 00 a 0 : 11 5. 00 1. 2e-5 E 0 : 24 5. 00 9 .9e-6 0 : 38 5. 00 9 . 2e-6 6 Geometric Mean 1. 0e-5 G-7 moo. Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-3 Test Date: 5/14/91 Interval #2 First Manometer Tape Reading: 30 inches Test #2 Initial Height of Water Above Gage: 4 . 060 feet (2nd) Packer Inflation Pressure: 120 psi Gage Pressure: 12 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 . 00 - O : 13 5. 00 9.9e-6 O : 29 5. 00 8 . 1e-6 O : 46 5. 00 7 . 6e-6 1 : 4 5. 00 7 . 2e-6 1 : 22 5. 00 7 . 2e-6 1 : 42 5. 00 6.5e-6 Geometric Mean 7 . 7e-6 Interval #2 First Manometer Tape Reading: 25 inches Test #2 Initial Height of Water Above Gage: 4 . 477 feet (3rd) Packer Inflation Pressure: 120 psi Gage Pressure: 12 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) k 0 : 0 . 00 - a 0 : 18 5. 00 1 .2e-6 0 : 37 5. 00 6 . 8e-6 u 0 : 55 5. 00 7 . 2e-6 1 : 15 5. 00 6 . 5e-6 0 1 : 34 5. 00 6.8e-6 1 : 55 5. 00 6 . 2e-6 c 2 : 16 5. 00 6.2e-6 O 2 : 39 5. 00 5. 6e-6 Geometric Mean 6. 5e-6 G-8 S WCsa.5 Laidlaw Denver Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-3 Test Date: 5/14/91 Interval #2 First Manometer Tape Reading: 10 inches Test #3 Initial Height of Water Above Gage: 5.727 feet (1st) Packer Inflation Pressure: 120 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 . 00 - 0 : 44 5. 00 3 .7e-6 1 : 29 5. 00 3 . 6e-6 2 : 17 5. 00 3 .4e-6 3 : 7 5. 00 3 . 3e-6 3 : 59 5. 00 3 .2e-6 4 : 54 5. 00 3 . 0e-6 5 : 51 5. 00 2 . 9e-6 6 : 49 5. 00 2 . 9e-6 7 : 49 5. 00 2 .8e-6 8 : 54 5. 00 2 . 6e-6 10 : 4 5. 00 2 . 4e-6 Geometric Mean 3 . 0e-6 Interval #2 First Manometer Tape Reading: 20 inches Test #3 Initial Height of Water Above Gage: 4 . 893 feet (2nd) Packer Inflation Pressure: 120 psi Gage Pressure: 0 psi i Elapsed Manometer Hydraulic E Time Drop Conductivity Min :Sec (inches) (cm/s) T u 0 : 0 . 00 0 1 : 16 5 . 00 2 . 1e-6 "g 2 : 24 5. 00 2 . 4e-6 3 : 35 5. 00 2 . 3e-6 0. 4 : 46 5. 00 2 . 3e-6 6 : 1 5. 00 2 . 2e-6 7 : 22 5. 00 2 . 1e-6 Geometric Mean 2 .2e-6 G-9 9 'J L •J Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-3 Test Date: 5/14/91 Hole Diameter: 5. 875 inches Depth Interval From: 46. 62 feet To: 58 . 66 feet Static Depth to Ground Water: 262 . 16 feet Height of Gage Above Ground: 6. 08 feet Inside Diameter of Manometer: 2 inches Interval #3 First Manometer Tape Reading: 42 inches Test #1 Initial Height of Water Above Gage: 3 . 060 feet Packer Inflation Pressure: 120 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) O : 0 . 00 - O : 21 1. 00 2 . 2e-6 O : 43 1. 00 2 . 1e-6 1 : 8 1.00 1.9e-6 1 : 38 1. 00 1. 5e-6 2 : 5 1.00 1. 7e-6 2 : 31 1.00 1.5e-6 3 : 11 1. 00 1. 4e-6 3 : 49 1. 00 1. 2e-6 4 : 29 1. 00 1.2e-6 5 : 11 1. 00 l. le-6 5 : 58 1. 00 1. Oe-6 6 : 51 1. 00 8 .9e-7 1 7 : 55 1. 00 7. 3e-7 E 9 : 10 1. 00 6. 3e-7 10 : 49 1. 00 4 .8e-7 u 12 : 2 1. 00 6 . 5e-7 14 : 20 1. 00 3 .4e-7 0 17 : 24 1. 00 2 . 6e-7 Q C Geometric Mean 9 . 9e-7 a G-10 Laidlaw Denver Regional Landfill (South) Tacker Testing August 20, 1991 Doty & Associates Hole: S-3 Test Date: 5/14/91 Interval #3 First Manometer Tape Reading: 11 inches Test #2 Initial Height of Water Above Gage: 5. 643 feet Packer Inflation Pressure: 120 psi Gage Pressure: 6 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 .00 - 0 : 30 1. 00 9 .9e-7 1 : 1 1. 00 9. 5e-7 1 : 40 1. 00 7 . 6e-7 2 : 14 1. 00 8.7e-7 2 : 49 1. 00 8 . 4e-7 3 : 25 1. 00 8 .2e-7 4 : 2 1. 00 8. 0e-7 4 : 39 1. 00 8 . 0e-7 5 : 16 1. 00 8 . 0e-7 5 : 54 1. 00 7 . 8e-7 6 : 32 1. 00 -7 .8e-7 7 : 1-0 1. 00 7 . 8e-7 7 : 49 1. 00 7. 6e-7 8 : 27 1. 00 7 .8e-7 9 : 4 1. 00 8 . 0e-7 9 : 43 1. 00 7. 6e-7 10 : 22 1. 00 7 . 6e-7 11 : 3 1. 00 7 .2e-7 11 : 46 1. 00 6. 9e-7 4 12 : 31 1. 00 6. 6e-7 13 : 19 1. 00 6. 2e-7 -E 14 : 8 1. 00 6. 0e-7 u 14 : 59 1. 00 5 . 8e-7 N L o Geometric Mean 7 . 6e-7 m W c L d G-11 9 'J' j:- Laidlaw Denver Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-3 'Test Date: 5/14/91 Interval #3 First Manometer Tape Reading: 32 inches Test #3 Initial Height of Water Above Gage: 3 .893 feet Packer Inflation Pressure: 120 psi Gage Pressure: D psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 . 00 - 0 : 49 . 50 4 . 7e-7 1 : 38 .50 4 .7e-7 2 : 29 .50 4 . 5e-7 3 : 17 .50 4 . 8e-7 4 : 44 1. 00 5. 3e-7 6 : 7 1. 00 5.5e-7 7 : 33 1. 00 5. 3e-7 8 : 59 1. 00 5. 3e-7 10 : 22 1. 00 5. 5e-7 11 : 49 1. 00 5.3e-7 13 : 15 1.00 5. 4e-7 14 : 44 1. 00 5.2e-7 16 : 9 1. 00 5.4e-7 -Geometric Mean 5. 1e-7 L a a u r u w L c a E c a G-12 9 :C`33 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-4 Test Date: 5/13/91 Hole Diameter: 5 . 875 inches Depth Interval From: 84 . 24 feet To: 96. 28 feet Static Depth to Ground Water: 241. 83 feet Height of Gage Above Ground: 5 . 63 feet Inside Diameter of Manometer: 2 inches Interval #1 Test #1 Test aborted because the packers would not seat. a A a u T O 0 c 0 C, 0 w a G-13 ✓ rn a i. �.'_ Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-4 Test Date: 5/13/91 Hole Diameter: 5 . 875 inches Depth Interval From: 82 . 24 feet To: 94 .28 feet Static Depth to Ground Water: 241. 83 feet Height of Gage Above Ground: 5. 63 feet Inside Diameter of Manometer: 2 inches Interval #2 First Manometer Tape Reading: N/A inches Test #1 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 105 psi Gage Pressure: .5 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) O : 0 . 00 - O : 11 1. 00 2 . 0e-4 0 : 22 1. 00 2 . 0e-4 O : 33 1. 00 2 . 0e-4 1 : 25 5. 00 2 . 1e-4 2 : 20 5. 00 2 . 0e-4 3 : 12 5. 00 2 . 1e-4 4 : 3 5. 00 2 .2e-4 4 : 52 5. 00 2 . 3e-4 5 : 44 5. 00 2 . 1e-4 6 : 33 5.00 2 . 3e-4 7 : 24 5. 00 2 . 2e-4 8 : 14 5. 00 2 .2e-4 9 : 5 5. 00 2 . 2e-4 m 9 : 55 5. 00 2 . 2e-4 10 : 46 5. 00 2 .2e-4 0 11 : 36 5. 00 2 . 2e-4 L 12 : 27 5. 00 2 . 2e-4 0 13 : 17 5. 00 2 . 2e-4 14 : 8 5. 00 2 . 2e-4 c 14 : 58 5. 00 2 . 2e-4 6 Geometric Mean 2 . 1e-4 G-14 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-4 Test Date: 5/13/91 Interval #2 First Manometer Tape Reading: N/A inches 'Test #2 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 107 psi Gage Pressure: 3 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : . 0 . 00 - 0 : 41 5. 00 2 . 5e-4 1 : 22 5. 00 2 .5e-4 2 : 4 5. 00 2 . 5e-4 2 : 47 5. 00 2 .4e-4 3 : 27 5. 00 2 . 6e-4 4 : 8 5. 00 2 . 5e-4 4 : 50 5. 00 2 . 5e-4 5 : 31 5. 00 2 .5e-4 6 : 13 5. 00 2 . 5e-4 6 : 55 5. 00 2 .5e-4 7 : 37 5. 00 2 . 5e-4 8 : 18 5. 00 2 . 5e-4 8 : 59 5. 00 2 . 5e-4 9 : 41 5. 00 2 . 5e-4 10 : 23 5. 00 2 .5e-4 11 : 4 5. 00 2 . 5e-4 11 : 50 5. 00 2 . 3e-4 12 : 29 5. 00 2 . 7e-4 13 : 9 5. 00 2 . 6e-4 13 : 50 5. 00 2 . 5e-4 14 : 32 5. 00 2 .5e-4 15 : 14 5. 00 2 . 5e-4 Geometric Mean 2 . 5e-4 0 0 v c a G-15 Tr ..1, L.8 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-4 Test Date: 5/13/91 Interval #2 First Manometer Tape Reading: N/A inches Test #3 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 107 psi Gage Pressure: . 5 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 . 00 - 0 : 46 5. 00 2 . 4e-4 1 : 35 5. 00 2 . 3e-4 2 : 29 5.00 2 . 0e-4 3 : 25 5. 00 2 . 0e-4 4 : 24 3. 00 1.9e-4 5 : 24 5. 00 1. 8e-4 6 : 23 5.00 1.9e-4 7 : 24 5. 00 1. 8e-4 8 : 23 5. 00 1. 9e-4 9 : 24 5. 00 1. 8e-4 10 : 24 5. 00 1.8e-4 11 : 26 5.00 1.8e-4 12 : 28 5. 00 1. 8e-4 13 : 29 5. 00 1.8e-4 14 : 29 5. 00 1. 8e-4 15 : 31 5. 00 1. 8e-4 Geometric Mean 1. 9e-4 I N a T U T u d L C O 3 C 6 G-16 9.-r fl Laidlaw Denver Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-4 Test Date: 5/13/91 Hole Diameter: 5. 875 inches Depth Interval From: 70 . 00 feet To: 82 . 04 feet Static Depth to Ground Water: 241. 83 feet Height of Gage Above Ground: 5. 63 feet Inside Diameter of Manometer: 2 inches Interval #3 Test #1 Test aborted because the upper packer would not sea (1st) Interval #4 Test #1 Test aborted because the packers would not seat. (2nd) L a C a v 0 u O L L C 0 G-17 Laidlaw Denver. Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-4 Test Date: 5/13/91 Hole Diameter: 5 . 875 inches Depth Interval From: 50. 00 feet To: 62 . 04 feet Static Depth to Ground Water: 241.83 feet Height of Gage Above Ground: 5. 63 feet Inside Diameter of Manometer: 2 inches Interval #5 First Manometer Tape Reading: N/A inches Test #1 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 120 psi Gage Pressure: . 5 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 . 00 - 0 : 42 1. 00 8. 0e-5 1 : 26 1. 00 7. 6e-5 2 : 6 1. 00 8 . 4e-5 3 : 0 1. 00 6. 2e-5 4 : 0 1. 00 5. 6e-5 5 : 10 1. 00 4. 8e-5 6 : 23 1. 00 4 . 6e-5 7 : 45 1. 00 4 . 1e-5 9 : 17 1. 00 3 . 6e-5 11 : 0 1. 00 3 .2e-5 12 : 48 1. 00 3 . 1e-5 14 : 50 1. 00 2 .7e-5 $ 15 : 50 . 50 2 . 8e-5 $ Geometric Mean 4. 6e-5 v 0 a w G-18 s3av,33 ILaidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-4 Test Date: 5/13/91 Interval #5 First Manometer Tape Reading: N/A inches Test #2 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 120 psi Gage Pressure: 7. 5 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 . 00 - 0 : 34 1. 00 7.8e-5 1 : 5 1. 00 8 . 6e-5 1 : 58 2 . 00 1. 0e-4 2 : 26 1. 00 9 .5e-5 3 : 22 2 . 00 9 .5e-5 4 : 34 2 . 00 7 .4e-5 5 : 55 2 . 00 6. 6e-5 7 : 18 2 . 00 6.4e-5 8 : 44 2 . 00 6.2e-5 10 : 24 2 . 00 5. 3e-5 12 : 9 2 . 00 5. 1e-5 13 : 58 2 . 00 4 . 9e-5 15 : 59 2 . 00 4 . 4e-5 Geometric Mean 6 . 8e-5 o_ E G-19 ( fcno Zaidlaw Denver Regional Landfill (South) Tacker Testing August 20 , 1991 "Doty & Associates :Hole: S-4 Test Date: 5/13/91 Interval #5 First Manometer Tape Reading: N/A inches Test #3 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 130 psi Gage Pressure: .5 psi Elapsed Flowmeter Hydraulic -Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 . 00 - 1 : 12 . 50 2 . 3e-5 2 : 32 . 50 2 . 1e-5 3 : 50 . 50 2 . 1e-5 5 : 13 .50 2 . 0e-5 6 : 38 . 50 2 . 0e-5 8 : 29 . 50 1. 5e-5 10 : 26 . 50 1. 4e-5 12 : 50 .50 1. 2e-5 15 : 12 . 50 1.2e-5 Geometric Mean 1.7e-5 L a n U T U U L C 0 G-20 Laidlaw Denver Regional landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-203 Test Date: 4/26/91 Hole Diameter: 4 . 00 inches Depth Interval From: 110. 9 feet To: 122 . 21 feet Static Depth to Ground Water: 147. 53 feet Height of Gage Above Ground: 4 . 16 feet Inside Diameter of Manometer: 2 inches Interval #1 first Manometer Tape Reading: 10 inches Test #1 Initial Height of Water Above Gage: 5.73 feet Packer Inflation Pressure: 100 psi Gage Pressure: 0 psi Elapsed Manometer hydraulic -Time Drop Conductivity Min :Sec (inches) (cm/s) O : -0 . 00 O : a 1. 00 2 . 9e-6 O : 19 1. 00 2 . 6e-6 O : 30 1. 00 2 .4e-6 O : 41 1. 00 2 .4e-6 O : 52 1. 00 2 .4e-6 1 : 2 1. 00 2 . 6e-6 1 : 13 1. 00 2 . 4e-6 1 : 24 1. 00 2 .4e-6 1 : 35 1. 00 2 .4e-6 1 : 46 1. 00 2 .4e-6 1 : 57 1. 00 2 .4e-6 2 : S 1. 00 2 . 4e-6 2 : 19 1. 00 2 . 4e-6 2 : 32 1. 00 2 . Oe-6 1 2 : 44 1. 00 2 . 2e-6 ✓ 2 : 56 1. 00 2 . 2e-6 3 : a 1. 00 2 . Oe-6 3 : 20 1. 00 2 . 4e-6 ✓ 3 : 33 1. 00 2 . Oe-6 3 : 46 1. 00 2 . Oe-6 3 : 59 1.-00 2 . Oe-6 4 : 11 1. 00 2 . 2e-6 4 : 24 1. 00 2 . Oe-6 4 : 38 1. 00 1. 9e-6 4 : 51 1. 00 2 . Oe-6 Continued on next page G-21 Laidlaw Denver Regional Landfill (South) Packer Testing August 2D , 1391 -Doty -& Associates Hole: S-203 Test Late: 4/26/91 Elapsed Manometer Hydraulic Time Drop -Conductivity Min :Sec (inches) (cm/s) 5 : -6 1.00 1.8e-6 5 : 21 1.00 1.8E-6 5 : 3-6 1.00 1. 8E-6 5 : 50 1. 00 1. 9e-6 6 7 1.00 1. 6e-6 6 : 24 1.-00 1.6E-6 6 : 42 1. 00 1.5e-6 6 : 58 1.00 1.7E-6 7 : 13 1. 00 1.8e-6 7 : 31 1.00 1. 5e-6 7 : 48 1. 00 1. 6E-6 8 : 6 1. 00 1. 5E-6 8 : 23 1. 00 1. 6e-6 8 : 42 1. 00 1. 4e-6 8 : 58 1.00 1.7e-6 9 : 10 1.D0 2 . 2e-6 9 : 2-5 1.D0 1.8e-6 9 : 39 1.-00 1.9e-6 9 : 52 1. 00 2 . 1e-6 10 : 6 1. 00 1.9e-6 10 : 21 1. 00 1.8e-b 10 : 35 1.00 1. 9e-6 10 : 50 1. 00 1. 8e-6 11 : 6 1.00 1. 7e-6 11 : 21 1. 00 1. 8e-6 a Geometric Mean 2 . 0e-6 T 0 0 c G-22 n Laidlaw Denver -Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-293 Test Date: 4/26/91 Interval #1 First Manometer Tape : Reading: N/A itches Test #2 Initial -Height of Water Above Gage: N/A feet Packer anflati-on Pressure: 1113 psi Gage Pressure: 19 psi Elapsed Fl-owmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 13 .D0 - 2 : 2 . 50 6. 08-5 4 : 4 . 50 -6. 0e-5 6 : 4 . 50 -6. le-5 8 : 5 . 50 -6. 0e-5 ' 9 : 58 . 50 11 : -46 . 50 6-8e-5 13 : 27 .50 7. 3e-5 15 : 7 . 50 7 .3e-6 Geometric Mean 6.5e-5 L 4 E u U L L C 9O N C a G-23 ac-CZ28 Laidlaw Denver Regional landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-203 Test Date: 4/26/91 Interval #1 First Manometer Tape _Reading: 2 inches Test 43 Initial -Height of Water Above Gage: 6.-39 feet Packer Inflation Pressure: 110 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) O : 0 .30 - O : 14 1.00 1. 8e-6 O : 2-9 1.00 1.7e-6 0 : 45 1.00 1.6e-6 1 : 3 1.D0 1. 4e-6 1 : 22 1.D0 1.4e-6 1 : 41 1.30 1.4e-6 2 : 0 1.00 1.4e-6 2 : 20 1.00 1. 3e-6 2 : 42 1.00 1. 2e-6 3 : 2 1.30 1. 2e-6 3 : 23 1.30 1. 2e-6 3 : 44 1.00 1. 2e-6 4 : 0 1.30 1. 6e-6 4 : 13 1.30 2 . 0e-6 4 : 26 1.00 2 . 0e-6 4 : 40 1.00 1.9e-6 4 : 53 1.D0 2 . Oe-6 5 : 6 1.-00 2 . 0e-6 5 : 19 1.D0 2 . 0e-6 1 5 : 33 1.D0 1. 9e-6 5 : 46 1.D0 2 . 0e-6 6 : 0 1.D0 1.9e-6 v 6 : 13 1. 00 2 . 0e-b 6 : 27 1.D0 1.9e-b 0 6 : 4D 1.D0 2 . 0e-b v 6 : 54 1. 00 1.9e-6 5 7 : 8 1.00 1.9e-_6 L n 1 : 22 1.D0 1.9e-b 7 : 36 1.00 1. 9e-6 1 : 4S 1.D0 2 . 02-b 8 : 3 1. 00 1.92-b Continued on next _page G-2-4 5.3:Oq Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: 5-203 Test Date: 4/26/91 Elapsed Manometer • Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 8 : 17 1. 00 1.9e-6 8 : 31 1. 00 1.9e--6 8 : -45 1. 00 1.2e-6 9 : 0 1. 00 1. 9e-6 9 : 15 1. 00 1.8e-6 9 : 29 1. 00 1.9e-6 9 : 44 1. 00 1.8e-6 9 : 58 1. 00 1.9e-6 10 : 13 1. 00 1.8e-6 10 : 27 1. 00 1.9e-5 10 : 41 1. 0-0 1. 9e-6 1-0 : 56 1. 010 1. 8e-6 11. : 11 1. 0-0 1.8e-6 11 : 25 1. 00 1.8e-5 11 : 42 1. 00 1.7e-6 11. : 57 1. 00 1.8e-6 12 : 12 1. 00 1.8e-6 12 : 27 1. 00 1.8e-6 12 : 42 1. 00 1.8e-6 12 : 58 1. 00 1.7e-5 13 : 13 1. 00 1. 8e-6 13 : 28 1. 00 1.8e-5 13 : 44 1. 00 1. 7e-6 13 : 59 1. 00 1.8e-6 14 : 15 1. 00 1. 7e-6 14 : 31 1. 00 1. 7e-6 14 : -48 1. 00 1. 62-5 a Geometric Mean 1. 7e-6 G-25 Laidlaw Denver Regional Landfill (South) Packer Testing August 210, 1991 Doty & Associates Hole: S-203 Test Date: 4/26/91 Hole Diameter: 4. 00 inches Depth Interval From: 92 . 6 feet To: 103 . 91 feet Static Depth to Ground Water: 1-47. 53 feet Height of Gage Above Ground: 4 . 16 feet Inside Diameter of Manometer: 2 inches Interval #2 First 1vIanometer Tape Reading: N/A inches Test #1 Initial Height of Water above Gage: N/A feet Packer Inflation Pressure: 105 psi Gage Pressure: 3 .5 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/-s) O : 0 . 0-0 - 0 : 10 1. 00 2 .2e-4 O : 21 1. 010 2 .De-4 0 : 32 1. 010 2 .De-4 0 : 42 1. 0D 2 .2e-4 O : 53 1. 00 2 .oe-4 1 : 4 1. 010 2 . 0e-4 1 : 14 1. 0D 2 .2e-4 1 : 25 1. 010 2 .De-4 1 : 35 1. 0D 2 .2e-4 2 : 30 5. 0D 2 .De-4 3 : 24 5. 010 2 .De-4 4 : 19 5. 010 2 .De-4 I 5 : 15 5. 010 2 .De-4 6 : 11 5. 013 2 .De-4 Ti 7 : 8 5. 0D 1. 9e-4 u 8 : 4 5. 00 2 .oe-4 W 9 : 2 5. 0D 1.9e-4 0 1D : 1 5. 010 1.-9e-4 v 11 : 2 5. 0D 1.Se-4 12 : 2 5. 00 1.8e-4 L a 13 : 3 5. 0D 1.S a-4 14 : 6 5. 0-0 1. 7e-4 15 : 9 5. 010 1. 7e-4 Geometric Mean 2 . 0e-4 G-2b 423 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-203 Test Date: 4/26/91 Interval #2 First Manometer Tape Reading: N/A inches Test #2 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 104 psi Gage Pr-assure: 13 .5 psi Elapsed Flowmet2r Hydraulic Time Change Conductivity Min :sec (gallons) (cm/s) 0 : 0 . 0O - 0 : 41 5. 60 2 . 22-4 1 : 24 5. 00 2 . 12-4 2 : 6 5. 00 2 . 2e-4 2 : 48 5. 0D 2 . 2e-4 3 : 30 5. 00 2 . 2e-4 4 : 13 5. 00 2 . 1e-4 4 : 55 5. 0D 2 . 2e-4 5 : 39 5. 00 2 . 1e-4 6 : 22 5. 0D 2 . 1e-4 7 : 6 5. 00 2 . 12-4 7 : 48 5. 00 2 . 2e-4 8 : 33 5. 00 2 . 0e-4 9 : 17 5. 00 2 . 1e--4 10 : 2 5. 00 2 . 0e--4 10 : 47 5. 00 2 . 0e-4 11 : 34 5. 00 1.9e-4 Geometric Mean 2 . le-4 L a a a w u U L L C O V Y G-27 420033 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-203 Test Date: 4/29/91 Hole Diameter: 4 . 00 inches Depth Interval From: 69 .85 feet To: 81. 16 feet Static Depth to Ground Water: 147 .53 feet Height of -Gage Above Ground: 5 . 11 feet Inside Diameter of Manometer: 2 inches Interval #3 First Manometer Tape Reading: 30 inches Test #1 Initial Height of Water Above Gage: 4 . 05 feet Packer Inflation _Pressure: 105 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/-s) 0 : 0 . 00 - 4 : 47 . 23 3 .4e-8 9 : 18 .2-5 3 . 6e-8 17 : 56 .23 1.9e-8 Geometric Mean 2 .S a-8 Interval #3 First Manometer TapeReading: 55 inches Test #2 Initial Height of Water Above Gage: 1.89 feet Packer Inflation Pressure: 103 psi Gage Pressure: 13 psi B.B. Elapsed Manometer Hydraulic -3 Time Drop Conductivity Min :Sec (inches) (cm/s) u v 0 : 0 . 00 - ° 1 : 4D .50 1.3e-7 $ 3 : 49 .50 1.2e-7 6 : 28 .50 9 .2e-8 0. 9 : 39 .50 7 . 8e-8 14 : 47 . 50 4 . 8e-8 17 : 7 . 13 2 .7e-S a-S Geometric Mean 7. 4e-S G-28 53:0:33 Laidlaw Denver Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-203 Test Date: 4/26/91 Interval #3 First Manometer Tape Reading: 30 inches Test #3 Initial Height of Water Above Gage: 4. 06 feet Packer Inflation Pressure: 103 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 . 00 - 1 : 36 . 25 1. Oe-7 2 : 51 .25 1. 3e-7 4 : 15 .25 1. 2e-7 5 : 36 .25 1.2e-7 6 : 49 . 25 1. 3e-7 8 : 1D . 25 1. 2e-7 9 : 34 . 25 1. 2e-7 10 : 51 . 25 1.3e-7 12 : 15 . 25 1.2e-7 13 : 30 .25 1. 3e-7 14 : 52 . 25 1.2e-7 16 : 7 . 25 1. 3e-7 Geometric Mean 1.2e-7 L a N n U T U N L C 0 V N C L a G-29 , v:43:3 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-203 Test Date: 4/29/91 Hole Diameter: 4 . 00 inches Depth Interval From: 33 . 45 feet To: 44 .7_6 feet Static Depth to Ground Water: 147. 53 feet Height of Gage Above Ground: 5. 61 feet Inside Diameter of Manometer: 2 inches Interval 44 First Manometer Tape Reading: N/A inches Test #1 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 110 psi Gage Pressure: 0 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 . 00 - 3 : 0 1. 00 3 . 0e-5 5 : 38 .5D 1. 7e-5 10 : 54 .50 8 . 6e-6 15 : 30 .2D 3 . 9e-6 Geometric Mean l. le-5 Interval #4 First Manometer Tape Reading: N/A inches Test #2 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 110 psi I Gage Pressure: 4 . 5 psi a -g Elapsed Flowmeter Hydraulic u Time Change Conductivity Min :Sec (gallons) (cm/s) 3 0 : D . 00 - 2 : 33 . 50 1. 4e-5 0. 5 : 20 .50 1.3e-5 9 : 40 .50 8 . 4e-_6 12 : 46 . 50 1.2e-5 15 : D . 50 1. 6e-5 Geometric Mean 1. 3e-5 G-30 nnLL�. V 7 cj Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-203 Test Date: 4/26/91 Interval #4 First Manometer Tape Reading: 20 inches Test #3 Initial -Height of Water Above Gage: 4 . 89 feet Packer Inflation Pressure: 11O psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 . 00 - 1 : 0 7. 00 7. 8e-6 1 : 21 2 . 00 6 .4e-6 1 : 41 2 . 00 6. 7e-6 2 : 2 2 . 00 6.4e-6 2 : 26 2 . 00 5.7e-6 2 : 49 2 . 00 5. 9e-6 3 : 15 2 . 00 5. 3e-6 3 : 41 2 . 00 5. 3e-6 4 : 7 2 . 00 5. 3e-6 4 : 36 2 . 00 4 .8e-6 5 : 4 2 . 00 5. 0e-6 5 : 28 2 . 0-0 5 . 8e-6 5 : 50 2 . 00 6. 3e-6 6 : 9 2 . 00 7 . 4e-6 6 : 29 2 .00 7 . 0e-6 6 : 48 2 . 00 7 .4e-6 7 : S 2 . 00 7.1e-6 7 : 27 2 . 00 7 . 5e-6 7 : 48 2 . 00 6.8e-6 8 : 9 2 . 00 6. 8e-6 8 : 33 2 . 00 6. 0e-6 Geometric Mean 6. 3e-6 0 0 0 O v 0 • G-31 191:0043,9 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-204 Test Date: 4/24/91 Hole Diameter: 4 . 00 inches Depth Interval From: 75.25 feet To: 86.56 feet Static Depth to Ground Water: 84 .92 feet Height of Gage Above Ground: 5.86 feet Inside Diameter of Manometer: 2 inches Interval #1 First Manometer Tape Reading: N/A inches Test #1 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 100 psi Gage Pressure: .25 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :sec (gallons) (cm/s) 0 : 0 . 00 - 0 : 45 . 50 3 . 1e-5 1 : 31 .50 3 . 0e-5 2 : 21 .50 2 .8e-5 3 : 9 . 50 2 .9e-5 4 : 1 .50 2 .7e-5 4 : 56 . 50 2 . 5e-5 5 : 45 .50 2 .8e-5 6 : -40 . 50 2 . 5e-5 7 : 36 .50 2 . 5e-5 8 : 32 . 50 2 .5e-5 9 : 30 .50 2 .4e-5 10 : 34 .50 2 .2e-5 11 38 .50 2 .2e-5 13 : 42 1. 00 2 . 2e-5 14 : 4-8 . 50 2 . 1e-5 15 : 57 .50 2 . 0e-5 L Geometric Mean 2 .5e-5 v C L a G-32 :31Wea3 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Dotv & Associates Hole: S-204 Test Date: 4/24/91 Interval #1 First Manometer Tape Reading: N/A inches Test #2 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 100 psi Gage Pressure: 12 .25 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 .00 - 0 : 45 .50 2 . 3e-5 1 : 41 . 50 1. 9e-5 2 : 25 .50 2 . 3e-5 3 : 15 . 50 2 . 1e-5 4 : 4 .50 2 . 1e-5 4 : 53 . 50 2 . 1e-5 5 : 44 . 50 2 . 1e-5 6 : 30 .50 2 . 3e-5 7 : 23 . 50 2 . 0e-5 8 : 12 . 50 2 . 1e-5 9 : 5 . 50 2 . 0e-5 10 : 0 .50 1. 9e-5 10 : 54 .50 1. 9e-5 11 : 47 .50 2 . 0e-5 12 : 39 . 50 2 . 0e-5 13 : 35 .50 1.9e-5 14 : 31 . 50 1.9e-5 15 : 23 . 50 2 . 0e-5 $ Geometric Mean 2 . 1e-5 G-33 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-204 Test Date: 4/24/91 Interval #1 First Manometer Tape Reading: N/A inches Test #3 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 100 psi Gage Pressure: 0 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : D . 00 - 1 : 26 .50 1. 6e-5 2 : 5b .50 1.5e-5 4 : 23 . 50 1. 6e-5 5 : 533 .50 1. 6e-5 7 : 2-0 . 50 1. 6e-5 8 : 48 .50 1. 6e-5 10 : 17 .50 1. 6e-5 11 : 48 .50 1.5e-5 13 : 18 . 50 1. 6e-5 14 : 51 . 50 1. 5e-5 16 : 2-4 .50 1.5e-5 Geometric Mean 1. 6e-5 a u O w O 0 C L a G-34 Uj 23 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-204 Test Date: 4/24/91 Hole Diameter: 4 . 00 inches Depth Interval From: 47. 25 feet To: 58. 56 feet Static Depth to Ground Water: 84 .92 feet Height of Gage Above Ground: 5. 86 feet Inside Diameter of Manometer: 2 inches Interval #2 First Manometer Tape Reading: 30 inches Test #1 Initial Height of Water Above Gage: 4. 06 feet Packer Inflation Pressure: 100 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 .00 - 3 : 39 1. 00 2 . 4e-7 10 : 20 1. 0D 1. 3e-7 20 : 35 1. 00 8 .5e-8 Geometric Mean 1. 4e-7 Interval #2 First Manometer Tape Reading: 30 inches Test #2 Initial Height of Water Above Gage: 4. 060 feet Packer Inflation Pressure: 105 psi Gage Pressure: 5 psi a Elapsed Manometer Hydraulic Time Drop Conductivity v Min :Sec (inches) (cm/s) 0 0 : D . 00 - E 1 : 53 .50 2 . 1e-7 3 : 55 .50 1.9e-7 C. 6 : 6 . 50 1. 8e-7 8 : 17 . 50 1. 8e-7 10 : 30 .50 1. 8e-7 12 : 40 . 50 1. 8e-7 15 : 5 .50 1. 6e-7 Geometric Mean 1. 8e-7 G-35 ;rir 28 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-204 Test Date: 4/24/91 Interval #2 First Manometer Tape Reading: 30 inches Test #3 Initial Height of Water Above Gage: 4. 06 feet Packer Inflation Pressure: 106 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :sec (inches) (cm/s) 0 : D . 00 - 0 : 27 . 50 9.7e-7 7 : 52 .50 5.9e-8 18 : 59 . 50 3 . 9e-8 Geometric Mean 1. 3e-7 L a a u U d C O V W C C. G-36 FTC 03 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-204 Test Date: 4/24/91 Hole Diameter: 4. 00 inches Depth Interval From: 39 .25 feet To: 50. 56 feet Static Depth to Ground Water: 84 . 92 feet Height of Gage Above Ground: 5. 86 feet Inside Diameter of Manometer: 2 inches Interval #3 First Manometer Tape Reading: 9. 5 inches Test #1 Initial Height of Water Above Gage: 5.77 feet Packer Inflation Pressure: 105 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) O : 0 . 00 - O : 23 1. 00 2 .5e-6 O : 44 1. 00 2 . 8e-6 O : 56 .50 2 . 4e-6 1 : 7 . 50 2 .7-e-6 1 : 18 .50 2 .7e-6 1 : 42 1. 00 2 .4e-6 2 : 7 1. 00 2 . 3e-6 2 : 32 1. 00 2 . 3e-6 3 : 0 1. 00 2 . 1e-6 3 : 28 1. 00 2 . 1e-6 3 : 56 1. 00 2 . 1e-6 4 : 24 1. 00 2 . 1e-6 $ 4 : 54 1. 00 2 . 0e-6 5 : 24 1. 00 2 . 0e-6 v 5 : 56 1. 00 1.9e-6 6 : 27 1. 00 1. 9e-6 7 : 1 1. 00 1.7e-6 0 7 : 34 1. 00 1.8e-6 8 : 9 1. 00 1. 7e-6 8 : 45 1. 00 1. 7e-6 9 : 23 1. 00 1. 6e-6 10 : 1 1. 00 1. 6e-6 10 : 40 1. 00 1. 5e-6 11 : 21 1. 00 1. 5e-6 Continued on next page G-37 a-• Yi'L'L5 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-204 Test Date: 4/24/91 Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 12 : 4 1. 00 1.4e-6 12 : 47 1. 00 1. 4e-6 13 : 32 1. 00 1.3e-6 14 : 17 1. 00 1. 3e-6 15 : ) 1. 00 1. 3e-6 Geometric Mean 1.9e-6 a a U d L C 9O N C L 6 G-38 Laidlaw Denver Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-204 Test Date: 4/24/91 Interval #2 First Manometer Tape Reading: 8 inches Test #2 Initial Height of Water Above Gage: 5. 893 feet Packer Inflation Pressure: 100 psi Gage Pressure: 9 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) O : 0 . 00 - O : 29 1. 00 1. 6e-6 1 : 1 1. 00 1.4e-6 1 : 3B 1. 00 1. 3e-6 2 : 1-0 1. 00 1.4e-6 2 : 45 1. 00 1. 3e-6 3 : 2D 1. 00 1. 3e-6 3 : 56 1. 00 1. 3e-6 4 : 31 1. 00 1. 3e-6 5 : B 1. 00 1.2e-6 5 : 44 1. 00 1. 3e-6 6 : 1:9 1. 00 1. 3e-6 6 : 54 1. 00 1. 3e-6 7 : 213 1. 00 1. 3e-6 8 : 6 1. 00 1.2e-6 8 : 41 1. 00 1. 3e-6 9 : 17 1.00 1. 3e-6 9 : 51 1. 00 1. 4e-6 10 : 27 1. 00 1. 3e-6 11 : 2 1. 00 1. 3e-6 11 38 1. 00 1. 3e-6 a 12 : 12 1. 00 1.4e-6 Z 12 : 49 1. 00 1. 2e-6 u 13 : 23 1. 00 1. 4e-6 14 : 0 1. 00 1. 2e-6 0 14 : 35 1. 00 1. 3e-6 ✓ 15 : 11 1. 00 1. 3e-6 0. Geometric Mean 1. 3e-6 G-39 ::;CC' S Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-204 Test Date: 4/24/91 Interval #2 First Manometer Tape Reading: 35 inches Test #3 Initial Height of Water Above Gage: 3 . 64 feet Packer Inflation Pressure: 105 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 . 00 - 0 : 47 1. 00 1. 3e-6 1 : 32 1. 00 1. 3e-6 2 : 12 1. 00 1. 5e-6 2 : 5b 1. 00 1.4e-6 3 : 42 1. 00 1. 3e-6 4 : 3D 1. 00 1. 3e-6 5 : 1b 1. 00 1. 3e-6 6 : 3 1. 00 1. 3e-6 6 : 4-9 1. 00 1. 3e-6 7 : 37 1. 00 1. 3e-6 8 : 25 1.00 1. 3e-6 9 : 11 1. 00 1. 3e-6 9 : 58 1. 00 1. 3e-6 10 : 44 1. 00 1. 3e-6 11 : 30 1. 00 1. 3e-6 12 : la 1. 00 1. 3e-6 13 : 7 1. 00 1. 3e-6 13 : 55 1. 00 1. 3e-6 14 : 45 1. 00 1. 2e-6 15 : 35 1. 00 1. 2e-6 Geometric Mean 1. 3e-6 v 0 3 a` G-40 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-204 Test Date: 4/24/91 Hole Diameter: 4. 00 inches Depth Interval From: 23 . 69 feet To: 41. 09 feet Static Depth to Ground Water: 84. 92 feet Height of Gage Above .Ground: 5.86 feet Inside Diameter of Manometer: 2 inches Interval #4 First Manometer Tape Reading: N/A inches Test #1 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 105 psi Gage Pressure: 0 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : .O . 00 - 0 : 21 1. 00 2 . 2e-4 0 : 44 1. 00 2 . 0e-4 1 : ' 1. 00 1. 9e-4 1 : .32 1. 00 1.9e-4 1 : 55 1. 00 2 . 0e-4 2 : 2D 1. 00 1. 8e-4 2 : 44 1.00 1.9e-4 3 : S 1. 00 1.8e-4 3 : 34 1. 00 1. 8e-4 3 : 59 1. 00 1.9e-4 4 : 24 1. 00 1.9e-4 4 : 50 1. 00 1.8e-4 1 5 : 15 1. 00 1.9e-4 E 5 : 41 1. 00 1. 8e-4 6 : 1 1. 00 1. 8e-4 6 : 34 1. 00 1.7e-4 7 : 0 1. 00 1.8e-4 0 7 : 27 1. 00 1.7e-4 -g 7 : 54 1. 00 1. 7e-4 t 8 : 20 1. 00 1. 8e-4 8 : 47 1. 00 1. 8e-4 9 : 14 1. 00 1. 8e-4 9 : 42 1. 00 1. 7e-4 10 : 9 1. 00 1. 8e-4 Continued on next page G-41 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-204 Test Date: 4/24/91 Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 10 : 37 1. 00 1. 7e-4 11 : 6 1.00 1. 7e-4 11 : 34 1. 00 1.7e-4 12 : 2 1. 00 1.7e-4 12 : 30 1. 00 1.7e-4 13 : 0 1. 00 1. 6e-4 13 : 28 1. 00 1. 7e-4 13 : 57 1. 00 1.7e-4 14 : 25 1. 00 1.7e-4 14 : 54 1. 00 1.7e-4 15 : 23 1. 00 1. 7e-4 Geometric Mean 1. 8e-4 L a a E u 0 L L O 0 3 G-42 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-208 Test Date: 5/ 6/91 Hole Diameter: 4 . 00 inches Depth Interval From: 134 . 69 feet To: 146. 00 feet Static Depth to Ground Water: 142 . 24 feet Height of Gage Above Ground: 6. 03 feet Inside Diameter of Manometer: 2 inches Interval #1 First Manometer Tape Reading: N/A inches Test #1 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 105 psi Gage Pressure: 0 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 . 00 - 2 : 47 1. 00 9 .9e-6 4 : 29 .50 8. 1e-6 6 : 22 .50 7 . 3e-6 8 : 20 . 50 7 . 0e-6 10 : 47 .50 5. 6e-6 13 : 9 . 50 5. 8e-6 15 : 34 .50 5.7e-6 Geometric Mean 6. 9e-6 a u d C 0 a G-43 onn.^13 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-208 Test Date: 5/ 6/91 Interval #1 First Manometer Tape Reading: N/A inches Test #2 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 105 psi Gage Pressure: 25 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) O : 0 . 00 - D : 10 1. 00 1. 2e-4 0 : 20 1. 00 1. 2e-4 0 : 30 1. 00 1. 2e-4 O : 40 1. 00 1. 2e-4 O : 51 1. 00 l. le-4 1 : 44 5. 00 l. le-4 2 : 42 5. 00 1. 0e-4 3 : 44 5. 00 9. 6e-5 4 : 51 5. 00 8 . 8e-5 6 : 2 5. 00 8. 3e-5 7 : 13 5. 00 8 . 3e-5 8 : 24 5. 00 8 . 3e-5 9 : 39 5. 00 7.9e-5 10 : 55 5. 00 7. 8e-5 12 : 20 5. 00 7 . 0e-5 13 : 50 5. 00 6. 6e-5 15 : 16 5. 00 6.9e-5 Geometric Mean 9 . 2e-5 a U T U 0 L C 0 F L G-44 ` ,1CC?! Iaidlaw Denver Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-208 Test Date: 5/ 6/91 Interval #1 First Manometer Tape Reading: N/A inches Test #3 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 105 psi Gage Pressure: 0 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 . 00 - 0 : 33 1.00 5. Oe-5 1 : 5 1. 00 5.2e-5 1 : 43 1. 00 4. 4e-5 2 : 21 1. 00 4. 4e-5 3 : 4 1. 00 3 .9e-5 3 : 51 1. 00 3 .5e-5 4 : 38 1. 00 3 . 5e-5 5 : 30 1. 00 3 .2e-5 6 : 24 1. 00 3 . 1e-5 7 : 20 1. 00 3 : 0e-5 8 : 14 1. 00 3 . 1e-5 9 : 8 1. 00 3 . 1e-5 10 : 6 1. 00 2 . 9e-5 11 : 2 1. 00 3 . Oe-5 11 : 57 1. 00 3 . Oe-5 12 : 50 1. 00 3 . 1e-5 13 : 45 1. 00 3 . Oe-5 14 : 42 1. 00 2 . 9e-5 15 : 41 1. 00 2 . 8e-5 a $ Geometric Mean 3 . 4e-5 O O a G-45 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-208 Test Date: 5/ 6/91 Hole Diameter: 4. 00 inches Depth Interval From: 119 . 25 feet To: 130. 56 feet Static Depth to Ground Water: 142 . 24 feet Height of Gage Above _Ground: 6. 03 feet Inside Diameter of Manometer: 2 inches Interval #2 First Manometer Tape Reading: 30 inches Test #1 Initial Height of Water Above Gage: 4 . 06 feet Packer Inflation Pressure: 105 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : D . 00 - 2 : 4) .25 3 .7e-8 5 : 53 . 25 3 . 2e-8 9 : 27 . 25 2 .8e-8 14 : 31 .25 2 . 0e-8 18 : 3 . 13 1. 5e-8 Geometric Mean 2 .5e-8 Interval #2 First Manometer Tape Reading: 45 inches Test #2 Initial Height of Water Above Gage: 2 .810 feet Packer Inflation Pressure: 105 psi Gage Pressure: 23 . 25 psi Elapsed Manometer Hydraulic $ Time Drop Conductivity Min :Sem (inches) (cm/s) 0 0 : D . 00 - 3 1 : 53 .50 7. 9e-8 3 : 24 .50 9 .8e-8 4 : 7 .50 2 . 1e-7 6 : 18 .50 7 .4e-8 8 : 54 .50 5. 4e-8 12 : 9 .50 4 . 6e-8 15 : 54 . 50 4 . 0e-8 Geometric Mean 7 . 3e-8 G-46 "I S T,aidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-208 Test Date: 5/ 6/91 Interval #2 First Manometer Tape Reading: 38 inches Test #3 Initial Height of Water Above Gage: 3 . 39 feet Packer Inflation Pressure: 105 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : -0 . 00 - 3 : 24 . 25 3 . 0e-8 9 : 4-0 . 25 1. 6e-8 15 : 59 . 25 1. 6e-8 Geometric Mean 2 . 0e-8 a n 0 O O d O 0 0 u 0 i G-47 t24 %-- 3 taidlaw Denver Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-208 Test Date: 5/ 6/91 Hole Diameter: 4 . 00 inches Depth Interval From: 87. 25 feet To: 98 .56 feet Static Depth to Ground Water: 142 .24 feet Height of Gage Above Ground: 6. 03 feet Inside Diameter of Manometer: 2 inches Interval #3 First Manometer Tape Reading: 30 inches Test #1 Initial Height of Water Above Gage: 4. 06 feet Packer Inflation Pressure: 106 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 . 00 — 1 : 32 .50 1.7e-7 3 : 17 . 50 1.5e-7 5 : 26 . 50 1.2e-7 8 : 1 .50 1. 0e-7 11 : 3 .50 8 .8e-8 15 : 12 . 50 6. 4e-8 Geometric Mean 1. 1e-7 L a a a L C O L a G-48 �n _strtS Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-208 Test Date: 5/ 6/91 Interval #3 First Manometer Tape Reading: 51 inches Test #2 Initial Height of Water Above Gage: 2 . 310 feet Packer Inflation Pressure: 106 psi Gage Pressure: 14 .75 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 . 00 - 1 : 3 .50 2 . 0e-7 2 : 11 . 50 1.8e-7 3 : 25 . 50 1.7e-7 4 : 42 .50 1. 6e-7 6 : 1 . 50 1. 6e-7 7 : 19 . 50 1. 6e-7 8 : 39 . 50 1.5e-7 10 : 2 . 50 1. 5e-7 11 : 24 . 50 1. 5e-7 12 : 46 . 50 1. 5e-7 14 : 13 . 50 1. 4e-7 15 : 37 . 50 1. 5e-7 Geometric Mean 1. 6e-7 k a v v v 0 0 O w c L a G-49 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates hole: S-208 Test Date: 5/ 6/91 Interval #3 First Manometer Tape Reading: 47 inches Test #3 Initial Height of Water Above Gage: 2 . 64 feet Packer Inflation Pressure: 106 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) O : 0 . 00 - 0 : 12 .50 1.3e-6 O : 24 .50 1. 3e-6 0 : 37 . 50 1. 2e-6 O : 51 . 50 1. 2e-6 1 : 6 .50 1. 1e-6 1 : 21 .50 1. 1e-6 1 : 38 .50 9 .5e-7 1 : 55 .50 9. 5e-7 2 : 14 . 50 8. 5e-7 2 : 35 . 50 7 . 7e-7 2 : 58 .50 7 . 1e-7 3 : 26 .50 5.8e-7 3 : 59 .50 4 . 9e-7 4 : 37 .50 4 . 3e-7 5 : 22 . 50 3 . 6e-7 6 : 19 . 50 2 . 9e-7 7 : 42 . 50 2 . 0e-7 13 : 59 . 50 4. 3e-8 16 : 15 . 13 3 . 0e-8 a a Geometric Mean 5. 2e-7 N a • n G-50 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-208 Test Date: 5/ 6/91 Hole Diameter: 4. 00 inches Depth Interval From: 33 .79 feet To: 45. 10 feet Static Depth to Ground Water: 142 . 24 feet Height of Gage Above Ground: 6. 03 feet Inside Diameter of Manometer: 2 inches Interval #4 First Manometer Tape Reading: 18 inches Test #1 Initial Height of Water Above Gage: 5. 06 feet (1st) Packer Inflation Pressure: 105 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 . 00 - 0 : 25 6. 0 1. 6e-5 0 : 48 6. 0 1.7e-5 1 : 15 6. 0 1. 5e-5 1 : 41 6. 0 1. 6e-5 2 : 5 6. 0 1. 7e-5 2 : 24 6. 0 2 . 2e-5 2 : 35 6. 0 3 . 8e-5 Geometric Mean 1. 9e-5 l a a U U L C 0 L G-51 Laidlaw Denver Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-208 Test Date: 5/ 6/91 Interval #4 First Manometer Tape Reading: 15 inches Test #1 Initial Height of Water Above Gage: 5. 31 feet (2nd) Packer Inflation Pressure: 105 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) O : 0 . 00 - O : 14 2. 0 9. 3e-6 O : 29 2 . 0 8. 7e-6 O : 41 2 . 0 1. 1e-5 0 : 56 2 . 0 8. 7e-6 1 : 15 2 . 0 6. 9e-6 1 : 28 2 . 0 1. 0e-5 1 : 44 2 . 0 8 . 3e-6 2 : 0 2 . 0 8. 3e-6 2 : 17 2 . 0 7. 8e-6 2 : 32 2 . 0 8.9e-6 2 : 48 2 . 0 8 .4e-6 3 : 8 2 . 0 6.7e-6 3 : 22 2. 0 9. 6e-6 3 : 36 2 . 0 9 .7e-6 3 : 51 2 . 0 9 . 1e-6 4 : 11 2 . 0 6.8e-6 4 : 37 2 . 0 5. 3e-6 5 : 5 2. 0 4 .9e-6 5 : 30 2 . 0 5.5e-6 $ 5 : 51 2 . 0 6. 6e-6 6 : 9 2 . 0 7 .7e-6 6 : 29 2 . 0 7. 0e-6 Geometric Mean 7. 8e-6 0 a Y G-52 Laidlaw Denver Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-208 Test Date: 5/ 6/91 Interval #4 First Manometer Tape Reading: 5 inches Test #1 Initial Height of Water Above Gage: 6. 14 feet (3rd) Packer Inflation Pressure: 106 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) A : 0 . 00 - 0 : 19 2 . 0 6.7e-6 0 : 37 2 . 0 7 . 1e-6 0 : 55 2 . 0 7. 1e-6 1 : 14 2 . 0 6. 8e-6 1 : 34 2 . 0 6. 5e-6 1 : 53 2 . 0 6. 8e-6 2 : 14 2 . 0 6. 2e-6 2 : 35 2 . 0 6.2e-6 2 : 55 2 . 0 6. 6e-6 3 : 16 2 . 0 6. 3e-6 3 : 38 2 . 0 6. 0e-6 3 : 59 2. 0 6. 3e-6 4 : 21 2 . 0 6. 0e-6 4 : 43 2 . 0 6. 1e-6 5 : 7 2 . 0 5. 6e-6 5 : 30 2 . 0 5. 8e-6 5 : 52 2 . 0 6. 1e-6 6 : 15 2 . 0 5. 9e-6 6 : 39 2 . 0 5. 6e-6 a 7 : 3 2 . 0 5.7e-6 $ 7 : 27 2 . 0 5.7e-6 7 : 53 2 . 0 5. 3e-6 u 8 : 18 2 . 0 5. 5e-6 8 : 43 2 . 0 5. 5e-6 9 : 10 2 . 0 5 . 1e-6 E 9 : 36 2. 0 5. 3e-6 10 : 4 2 . 0 5. 0e-6 L a Geometric Mean 6. 0e-6 G-53 `" 'G 23 Laidlaw Denver Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-208 Test Date: 5/ 6/91 Interval #4 First Manometer Tape Reading: 18 inches Test #2 Initial Height of Water Above Gage: 5 . 060 feet Packer Inflation Pressure: 106 psi Gage Pressure: 5 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) O : 0 . 00 - O : 24 2. 0 4. 8e-6 O : 5.0 2 . 0 4 . 4e-6 1 : 15 2 . 0 4 . 6e-6 1 : 40 2 . 0 4 . 6e-6 2 : 7 2 . 0 4. 3e-6 2 : 33 2 . 0 4. 4e-6 2 : 59 2 . 0 4. 4e-6 3 : 25 2 . 0 4. 4e-6 3 : 42 2 . 0 6. 8e-6 4 : 4 2. 0 5.2e-6 4 : 29 2. 0 4 . 6e-6 4 : 55 2 . 0 4 .4e-6 5 : 21 2 . 0. 4 .4e-6 5 : 47 2 . 0 4 .4e-6 6 : 13 2 . 0 4 .4e-6 6 : 39 2 . 0 4 . 4e-6 7 : 6 2 . 0 4 . 3e-6 7 : 33 2 . 0 4. 3e-6 7 : 51 2 . 0 6.4e-6 8 : 15 2 . 0 4 . 8e-6 8 : 41 2 . 0 4 .4e-6 v Geometric Mean 4 .7e-6 0 0 0 a c L a G-54 fir:ZWes, Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-208 Test Date: 5/ 6/91 Interval #4 First Manometer Tape Reading: 8 inches Test #3 Initial Height of Water Above Gage: 5. 89 feet Packer Inflation Pressure: 106 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic -Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 . 00 - 0 : 35 2 . 0 3 .7e-6 1 : 11 2 . 0 3 . 6e-6 1 : 47 2 . 0 3 . 6e-6 2 : 23 2 . 0 3 . 6e-6 3 : 0 2 . 0 3 . 5e-6 3 : 37 2 . 0 3 . 5e-6 4 : 14 2 . 0 3 . 5e-6 4 : 52 2 . 0 3 . 4e-6 5 : 31 2 . 0 3 . 4e-6 6 : 10 2 . 0 3 .4e-6 6 : 49 2 . 0 3 .4e-6 7 : 28 2 . 0 3 .4e-6 8 : 8 2 . 0 3 . 3e-6 8 : 49 2 . 0 3 . 3e-6 9 : 29 2 . 0 3 . 4e-6 10 : 11 2 . 0 3 . 2e-6 10 : 52 2 . 0 3 . 3e-6 11 : 34 2 . 0 3 .2e-6 12 : 17 2 . 0 3 . 2e-6 13 : 1 2 . 0 3 . 1e-6 13 : 44 2 . 0 3 . 2e-6 14 : 28 2 . 0 3 . 1e-6 v 15 : 12 2 . 0 3 . 1e-6 o Geometric Mean 3 .4e-6 3 a G-55 Laidlaw Denver Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-209 Test Date: 4/17/91 Hole Diameter: 4 . 00 inches Depth Interval From: 108. 29 feet To: 119 . 60 feet Static Depth to Ground Water: 81. 6 feet Height of Gage Above Ground: 4. 80 feet Inside Diameter of Manometer: 2 inches Interval #1 First Manometer Tape Reading: N/A inches Test #1 Initial Height of Water Above Gage: N/A feet _Packer Inflation Pressure: 125 psi Gage Pressure: 0 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 . 00 - 1 : 48 1. 00 1.9e-5 3 : 41 1. 00 1. 8e-5 6 : 5 1. 00 1. 4e-5 8 : 33 1. 00 1. 4e-5 10 : 77 1. 00 1. 8e-5 13 : 3 1. 00 1. 3e-5 15 : 26 1. 00 1.4e-5 Geometric Mean 1. 6e-5 L n U U d L O O 'O Y C L 6 G-56 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-209 Test Date: 4/17/91 Interval #1 First Manometer Tape Reading: N/A inches Test #2 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 125 psi Gage Pressure: 19 .5 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 . 00 - 0 : 25 1.00 5. 9e-5 0 : 51 1. 00 5. 7e-5 1 : 23 1. 00 4 . 6e-5 1 : 51 1. 00 5. 3e-5 2 : 22 1. 00 4 .8e-5 2 : 50 1. 00 5. 3e-5 3 : 22 1. 00 4 . 6e-5 3 : 51 1.00 5. 1e-5 4 : 22 1. 00 4 .8e-5 ' 4 : 55 1.00 4 .5e-5 5 : 33 1.00 3 .9e-5 6 : 12 1. 00 3 .8e-5 6 : 50 1. 00 3 . 9e-5 7 : 29 1. 00 3 . 8e-5 8 : 12 1. 00 3 .4e-5 8 : 53 1. 00 3 . 6e-5 9 : 37 1. 00 3 . 4e-5 10 : 20 1. 00 3 .4e-5 11 : 4 1. 00 3 .4e-5 1- 11 : 51 1. 00 3 . 1e-5 $ 12 : 37 1. 00 3 .2e-5 13 : 27 1. 00 3 . Oe-5 14 : 17 1. 00 3 . Oe-5 15 : 3 1. 00 3 .2e-5 5 E Geometric Mean 4. Oe-5 c d G-57 °L 3 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-209 Test Date: 4/17/91 Interval #1 First Manometer Tape Reading: N/A inches Test #3 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 125 psi Gage Pressure: 0 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 . 00 - 1 : 42 1. 00 2 . 0e-5 3 : 5 1. 00 2 . 5e-5 4 : 28 1. 00 2 . 5e-5 5 : 49 1. 00 2 .5e-5 7 : 10 1. 00 2 . 5e-5 8 : 33 1. 00 2 . 5e-5 9 : 55 1. 00 2 . 5e-5 11 : 17 1. 00 2 .5e-5 12 : 42 1. 00 2 .4e-5 14 : 6 1. 00 2 . 4e-5 15 : 28 1. 00 2 .5e-5 Geometric Mean 2 . 4e-5 I a a u T 0 0 c 0 V 0 c L a G-58 Laidlaw Denver Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-209 Test Date: 4/18/91 Hole Diameter: 4. 00 inches Depth Interval From: 87. 29 feet To: 98. 60 feet Static Depth to Ground Water: 81. 6 feet Height of Gage Above Ground: 4. 80 feet Inside Diameter of Manometer: 2 inches Interval #2 First Manometer Tape Reading: N/A inches Test #1 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 90 psi Gage Pressure: 0 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 . 00 - 0 : 40 1. 00 6. 2e-5 1 : 20 1. 00 6. 2e-5 2 : 2 1. 00 5.9e-5 2 : 45 1. 00 5. 8e-5 3 : 29 1. 00 5. 6e-5 4 : 13 1. 00 5. 6e-5 4 : 56 1. 00 5.8e-5 5 : 40 1. 00 5. 7e-5 6 : 24 1. 00 5.7e-5 7 : 9 1. 00 5. 5e-5 7 : 53 1. 00 5.7e-5 8 : 38 1.00 5. 6e-5 a 9 : 22 1. 00 5.7e-5 10 : 9 1. 00 5. 3e-5 IC 10 : 56 1. 00 5. 3e-5 11 : 42 1. 00 5.5e-5 0 12 : 29 1. 00 5. 3e-5 14 :13 : 18 7 1. 00 5. 1e-5 c 1. 00 5 , 1e-5 14 : 57 1. 00 5. 0e-5 0. 15 : 47 1. 00 5. Oe-5 Geometric Mean 5.5e-5 Interval #2 Test #2 Test aborted because the packers were leaking. G-59 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-209 Test Date: 4/18/91 Hole Diameter: 4. 00 inches Depth Interval From: 83 . 23 feet To: 94. 60 feet Static Depth to Ground Water: 81. 6 feet Height of Gage Above Ground: 4 .80 feet Inside Diameter of Manometer: 2 inches Interval #3 First Manometer Tape Reading: 30 inches Test #1 Initial Height of Water Above Gage: 4 . 06 feet (1st) Packer Inflation Pressure: 90 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 . 00 - 0 : 10 6.48 2 . 2e-5 0 : 20 6.96 2 .4e-5 0 : 30 6. 36 2 .2e-5 0 : 40 6. 12 2 . 1e-5 0 : 50 6. 00 2 . 1e-5 1 : 0 5.88 2 . 0e-5 Geometric Mean 2 . 1e-5 Interval #3 First Manometer Tape Reading: 20 inches Test #1 Initial Height of Water Above Gage: 4. 89 feet (2nd) Packer Inflation Pressure: 90 psi Gage Pressure: 0 psi aElapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) N 0 : 0 . 00 - ° 0 : 10 6. 24 2 . 1e-5 -E 0 : 20 5.76 1. 9e-5 `- 0 : 30 5. 88 2 . 0e-5 0. 0 : 40 5.40 1. 8e-5 0 : 50 5. 16 1.8e-5 1 : 0 4. 92 1. 7e-5 1 : 10 4 . 80 1. 6e-5 1 : 20 5.28 1. 8e-5 1 : 30 4. 56 1. 6e-5 Geometric Mean 1. 8e-5 G-60 .9.:::c.:423 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-209 Test Date: 4/18/91 Interval #3 First Manometer Tape Reading: 17 inches Test #1 Initial Height of Water Above Gage: 5. 14 feet (3rd) Packer Inflation Pressure: 90 psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : 0 . 00 - 0 : 10 8 .40 2 . 8e-5 0 : 20 8. 04 2 . 7e-5 0 : 30 7.56 2 .5e-5 0 : 40 7. 32 2 .5e-5 0 : 50 6.96 2 . 4e-5 1 : 0 6. 60 2 . 3e-5 1 : 10 6.48 2 . 2e-5 Geometric Mean 2 .5e-5 Interval #3 First Manometer Tape Reading: N/A inches Test #2 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 100 psi Gage Pressure: 13 . 75 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) a 0 : 0 . 00 - 0 41 1. 00 9. 1e-5 1. 00 9 . 6e-5 ° 1 23 1. 00 9 . 6e-5 v 1 45 1. 00 8 . 7e-5 1. 00 8 . 7e-5 2 58 1. 00 8. 3e-5 0. 2 : 34 1. 00 7 . 4e-5 2 : 58 1. 00 8 . 0e-5 3 : 22 1. 00 8 . 0e-5 Continued on next page G-61 CC3 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-209 Test Date: 4/18/91 Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 3 : 46 1. 00 8. Oe-5 4 : 8 1. 00 8.7e-5 4 : 32 1. 00 8 . Oe-5 4 : 58 1. 00 7.4e-5 5 : 26 1. 00 6. 9e-5 5 : 53 1. 00 7. 1e-5 6 : 44 2 . 00 7 .5e-5 7 : 9 1. 00 7. 7e-5 7 : 36 1. 00 7 . 1e-5 8 : 1 1. 00 7. 7e-5 8 : 29 1. 00 8 56 6. 9e-5 1. 00 7 . 1e-5 9 : 23 1. 00 7. 1e-5 9 : 49 1. 00 7.4e-5 10 : 17 1. 00 6. 9e-5 10 : 42 1. 00 7. 7e-5 11 : 10 1. 00 6.9e-5 11 : 36 1. 00 7 .4e-5 12 : 3 1. 00 7 . 1e-5 12 : 30 1. 00 7. 1e-5 12 : 57 1. 00 7. 1e-5 13 : 25 1. 00 6. 9e-5 13 : 53 1. 00 6. 9e-5 14 : 20 1. 00 7. 1e-5 14 : 48 1. 00 6. 9e-5 1 a 15 . 00 15 7. 1e-5 v 0 Geometric Mean 7 . 6e-5 T u 0 c 0 E c n G-62 T:C 3 Laidlaw Denver Regional Landfill (South) Tacker Testing August 20, 1991 Doty & Associates Hole: S-209 Test Date: 4/18/91 Interval #3 First Manometer Tape Reading: N/A inches Test #3 Initial Height of Water Above Gage: N/A feet Tacker Inflation Pressure: 100 psi Gage Pressure: 0 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 . 00 - 0 : 43 1. 00 6. Oe-5 1 : 26 1. 00 6. Oe-5 2 : 11 1. 00 5. 7e-5 2 : 57 1. 00 5. 6e-5 3 : 45 1. 00 5. 4e-5 A : 32 1. 00 5.5e-5 -5 : 20 1. 00 5. 4e-5 6 : 9 1. 00 5. 3e-5 7 : 0 1. 00 5. 1e-5 7 : 52 1. 00 5. Oe-5 B : 42 1. 00 5. 2e-5 9 : 34 1. 00 5. Oe-5 10 : 25 1. 00 5. 1e-5 11 : 17 1. 00 5. 0e-5 12 : 10 13 3 1. 00 4. 9e-5 1. 00 4 . 9e-5 13 : 54 1. 00 5. 1e-5 14 : 46 1. 00 5. Oe-5 15 : 37 1. 00 5. 1e-5 a Geometric Mean 5.5e-5 u u L C O a v a G-63 Laidlaw Denver Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-209 -Test Date: 4/18/91 Hole Diameter: 4. 00 inches Depth Interval From: 60. 61 feet To: 71. 92 feet Static Depth to Ground Water: 81. 6 feet Height of Gage Above Ground: 4. 80 feet Inside Diameter of Manometer: 2 inches Interval #4 First Manometer Tape Reading: N/A inches Test #1 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 90 psi Gage Pressure: 0 psi Elapsed Flowmeter _Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 . 00 - 4 : 59 1. 00 1. 1e-5 -8 : 22 . 50 8 .4e-6 11 : 56 .50 E . Oe-6 14 : 18 .25 _6. 0e-6 15 : 59 .25 8 .4e-6 Geometric Mean 8. 3e-6 a 0. 7 U O U v 0 0 v 0 L a G-64 fr-C'.w Laid--aw Denver Regional Landfill (South) Packer Testing August 29, 1991 Doty & Associates Hole: S-209 T-est Date: 4/18/91 Interval #4 first Manometer Tape Reading: N/A inches Test #2 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: S3 psi Gage Pressure: 10.25 psi Dlapsed Flowmeter -Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 . 00 - 0 : 36 .50 3 .5e-5 1 : 7 .50 4. 1e-5 1 : 26 1 : 38 .50 6. 7e-5 1 : 55 .50 l. le-4 21. 00 1. 5e-4 : 12 2 1. 00 1.5e-4 37 2 . 00 2 . oe-4 2 : 47 1. 00 2 . 6e-4 2 : 57 1. 00 2 . 6e-4 3 : 8 1. 00 2 . 3e-4 Geometric Mean 1.2e-4 a d z 0 v i L a G-65 Laidlaw Denver Regional Landfill (South) Packer _Testing August 20, 1991 Doty I Associates Hole: S-209 Test Date: 4/15/91 Hole Diameter: 4.00 inches Depth Interval From: 57.29 feet To: 68. 6-0 feet Static Depth to Ground Water: 81.6 feet Height o₹ Gage Above Ground: 4.80 feet Inside Diameter ofManometer: 2 inches Interval #5 First Manometer Tape heading: -N/A inches -Test #1 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 90 Psi Gage Pressure: 0 psi Elapsed Tlowmeter Hydraulic -Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 .00 - 0 : 43 1. 00 B . 3e-5 1 : 30 1. 00 7 .5e-5 2 : 20 1. 00 7.2e-5 3 : 11 1. 00 7 . Oe-5 4 : 4 1. 00 6.5e-5 5 : 4 1. 00 6.0e-5 6 : 0 1. 00 6 59 5. 4e-5 1. 00 6. 1e-5 7 : 59 1. 00 6. 0e-5 9 : 0 1. 00 5.9e-5 10 : 1 1. 00 5. 9e-5 11 : 4 1.00 5. 7e-5 a 12 4 1. 00 6. Oe-5 $ 14 : 6 1. 00 6. 1e-5 r 1. 00 5. 9e-5 v 15 : 8 1. 00 5. 9e-5 c 0 v Geometric Mean 6. 4e-5 c a G-66 Laidlaw Denver -Regional Landfill (South) Packer Testing August 20 , 1991 Doty & Associates Hole: S-209 Test Date: 4/19/91 Hole Diameter: 4 . 09 inches Depth Interval From: 48. 2-9 feet To: 59 . 60 feet Static Depth to Ground Water: '81. 6 feet Height of Gage Above Ground: 4. 8-0 feet Inside Diameter of Manometer: 2 inches interval #6 Test #1 Test aborted (could not get packers to interval) . Hole: S-209 Test Date: -4/19/21 Hole Diameter: 4 . 00 inches Depth Interval From: 37 .79 feet To: 49 . 10 feet Static Depth to Ground Water: 81. 6 feet Height of Gage Above Ground: 4 . 80 feet Inside Diameter of Manometer: 2 inches Interval 47 First Manometer Tape Reading: 10 inches Test #1 Initial Height of Water Above Gage: 5.73 feet (1st) Packer Inflation Pressure: 110 psi Gage Pressure: D psi Elapsed Manometer -Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) D : 0 . 00 - o 0 : 10 5. 96 4 . 3e-5 a 0 : 20 5. 52 3 .4e-5 -o 0 30 4 .20 2 . 6e-5 0 : 40 0 50 4 .32 2 . 7e-5 3 .54 2 . 4e-5 b 1 : D 3 . 72 2 . 4e-5 Ti : 20 3 . 12 2 . 0e-3 3 .24 2 . le-5 0. 1 : 30 3 . 00 1.9e-5 1 : 40 3 . 00 1.9e-5 1 : 50 3 . 00 2 . 0e-5 2 : 0 2 .88 1.9e-5 2 : 10 2 . 64 1.7e-5 2 : 20 2 . 7b 1-8e-5 2 : 30 2 .28 1.5e-5 Geometric Mean 2 . 2e-5 G-67 ._.t Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-209 Test Date: 4/19/91 Interval #7 First Manometer Tape heading: 10 inches Test #1 Initial Height -of Water Above -Gage: -5. 73 feet (2nd) Packer Inflation Pressure: no psi Gage Pressure: 0 psi. Elapsed Manometer Hydraulic Time Drop Conductivity Min :Sec (inches) (cm/s) 0 : D .D0 - 0 : 1D 10. 92 6.7e-5 0 : 20 8 .40 5.2e-5 D : 30 6.96 4. 4e-5 0 : 40 6. 00 3 .te-5 0 : 50 5. 04 3 .2e-5 1 : 0 4 .8D 3 .1e-5 1 : 10 -4. 68 3 . 1e-5 1 : 20 4 .20 2 .Ee-5 Geometric Mean 3 . 9e-5 a -12 U d C 0 L G-68 5103 Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Holm: 6-209 Test Mate: 4/19/91 Interval 47 First Manometer Tape Reading: N/A inches Test #2 Initial Height of Water Above Gage: N/A feet Packer Inflation Pressure: 110 psi Gage -Pressure: 5 psi Elapsed flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) (cm/s) 0 : 0 . 0D - 0 : 30 .5D 6. 7e-5 1 : 12 .5D 4.8e-5 1 : 50 .50 2 285. 3e-5 .50 5. 3e-5 3 : 11 .50 3 48 4 .7e-5 50 5. 5e-5 4 : 25 .50 5 05. 5e-5 .50 5.8e-5 5 : 33 .50 6. 1e-T3 6 : 5 . 50 6. 3e-5 6 : 37 .50 6. 3e-5 7 : 10 .50 6. 1e-5 8 : 14 1.-00 -6. 3e-5 9 : 19 1. 00 6.2e-5 10 : 29 1. 00 5. 8e-5 11 : -41 1. 00 5.6e-5 12 : 51 1. 00 14 4 3.5e-5 1. 0D 5.5e-5 15 : 1.9 1. OD ti 5.4e-5 co Geometric Mean 5. 7e-5 y a y c 0 3 c a G-b9 Laidlaw Denver Regional Landfill (South) Packer Vesting August 2D, 1991 Doty & Associates Hole: S-209 Test Date: 4/19/91 Interval 47 First Manometer Tape Reading: N/A inches Test #3 Initial Height of dater Above Gage: N/A feet Packer Inflation Pressure: 11D psi Gage Pressure: . 5 psi Elapsed Flowmeter Hydraulic Time Change Conductivity Min :Sec (gallons) 0 : 0 . 00 - 0 : 32 .5D 4 .7e-5 1 : 49 . 5D 4 . 4e-5 2 : 45 . 5D 4. 5e-5 3 : 54 .5D 3 .se-5 4 : 54 .5D 4 .2e-5 5 : 51 .5D 4 .4e-5 6 : 41 .5D 5.De-5 D e-5 7 : 34 .50 4. 7e-5 8 : 28 .50 4 .3e-5 9 : 1'7 .-50 5. 1e-5 10 8 . 50 4 . 9e-5 10 : 59 .50 4. 9e-5 11 : 50 .50 4 .9e-5 12 : 41 .30 4 .9E-5 13 : 33 .50 4 . 8E-5 14 : 30 .50 4.4s5 15 : 23 .50 4.7e-3 Geometric Mean -4 . 6-e-5 a a d Hole: S-209 Test Date: 4/13/91 L Hole Diameter: 4 . 00 inches a c Depth Interval From: 36.79 feet To: 48 . 10 feet Static Depth to Ground Water: 81. 6 feet Height of Gage Above Ground: 4 . 80 feet Inside -Diameter of Manometer: 2 inches Interval #13 Test 41 Test aborted (could not get packers to seat) . G-70 (1y Laidlaw Denver Regional Landfill (South) Packer Testing August 20, 1991 Doty & Associates Hole: S-209 Test Date: 4/19/91 Hole Diameter: 4. 00 inches Depth Interval From: 25. 29 feet To: 35.60 feet Static Depth to Ground Water: 81. 6 feet Height of Gage Above Ground: 4 .8D feet Inside Diameter of Manometer: 2 inches Interval #9 First Manometer Tape Reading: 15 inches Test #1 Initial Height of Water love Gage: 5. 31 feet Packer Inflation Pressure: 11n psi Gage Pressure: 0 psi Elapsed Manometer Hydraulic Time Drop Conductivity Min :Dec (inches) (cm/s) 0 : 0 . 0-0 - 1 : 0 3 . 6D 4 -8e-6 2 : 0 3 .-6D 4. 9e-6 3 : 0 3 .36 4 .6e-6 4 : 0 3 .24 4 . 4e-6 5 : 0 3 . 36 4.be-6 6 : 0 3 .24 4.5E-6 7 : 0 3 .36 4 .7e-6 8 : 0 3 . 24 4 . 6e-6 9 : 0 3 .-36 4. 8e-6 10 : 0 3 .48 5. Oe-6 11 : 0 3 . 24 4 . 7e-6 o a 13 0 3 .211 4. 7e-6 3 . 211 4 .le-5 14 3 . 12 4 . 6e-5 15 : 0 2 .88 4.3e-6 U 0 Geometric Mean 4 .-6e-6 0 0 G-71 APPENDIX H RECOVERY TESTS L a a u v c O v c 6 Laidlaw Denver Regional Landfill (South) Recovery Tests August 20, 1991 Doty & Associates S-203 RECOVERY TEST S-203 was repeatedly bailed -during the period June 7 through June 12, 1991, in order to developthe well. Approximately 0. 3 gallons were removed from the well each time, and the water level recovered to the static level fairly -quickly. On June 13 , the recovery was monitored for hydraulic conductivity estimation. The June 12 recovery data are shown on the following tables and figures. Analyses Analyses were performed using the Theis recovery method (Theis, 1935) , coupled with the Jacob straight line method (Cooper and Jacob, 1964) . The straight 1i-ne match is shown on one of the fallowing figures, yielding: Transmissivity = 7 . 4x1-0-6 ft2/min Assuming a storage coefficient of 0. 0101 (the water yielding material is a fully saturated coal. approximately 2 . 9 feet thick) , then u = 0.1002 at the end of the -test and is ₹hi-gher at earlier times; n must -be less than 0. 01 to meet the assumptions o₹ the analysis. Therefore, the Theis/Jacob analysis is strictly applicable only for the later times. This result was evaluated for reasonableness by performing a predictive analysis using the Theis recovery method. She -Theis a recovery method involves superposing an injection well on the $ withdrawal well at the time withdrawal ceased, and summing the rlrawdowns from each in order to simulate the recovering water levels. The best match is shown on an attached figure; the match was obtained using the values O Transmissivity = 1x10-4 ft2/min Storage = 10. 001 H1 Laidlaw Denver Regional Landfill (South) Recovery Tests Auciust 20, 1991 Doty & Associates Result The Theis match was quite adequate and the resulting hydraulic values, Conductivity = 1.8x10-5 cm/s Storage = 0.-001 should be used AS the result of -this test. L a u T u w L 0 0 E 0. H-2 t.,-I . _.! Laidlaw Denver Regional Landfill (South) Recovery Tests August 20, 1991 Doty & Associates S-203 RECOVERY TEST DATA Date: 6/12/91 Static Depth to Water: 101. 24 Bailing began: 10: 24 : 0 Bailing ceased: 10: 50: 0 Volume removed (gals) : . 35 Flow rate (gpm) : . 007 Length of inflow (ft) : 2 .-9 Material: Coal Depth to Time Water hrs min sec (feet) 10: 51: 25 102 . 95 10: 53 : 14 102 . 80 10: 54: 22 102 . 70 110: 55: 33 102 .-60 10: 56: 49 102 .50 110: 58: 4 102 .40 11: 0: 4 1102 . 30 11: 2 : 3-6 102 . 20 11: 5: 2B 1-02 . 10 11: 8: 31 1_02 . 00 11: 11: 59 101. 910 11: 15: 15 101.80 11: 18: 2-6 101. 710 11: 22 : 15 101. 610 11: 28 : 2-8 101.51) 11: 3-6: 45 101.40 12 : 3 : 25 101.24 O 0 O 0 V w a H-3 _ Cti253 S- 203 RECOVERY DATA 0 ,p .5 r• m V w v L 1 0 a N) L 0 a O a 1.5 r in N Coc o Nr v ., c a in 2 — 0 20 40 60 80 0 Recovery Time (min) Qs 0 0 S- 203 STRAIGHT LINE ANALYSIS 0 -B-- Data Straight line .5 1 a) 3 1.5 0 13 0 n 0 2 g o a — o N 2.5 0 o N c — W 3 a 0 .5 1 1.5 Log (t/t') >- 0 0 S-203 RECOVERY MATCH T=1E-4 ft2/min; S=0.001; Q=9.4E-4 ft3/min 0 —a— Data —x— Predicted .5 ti- a) C 3 1 0 D n g o - 1.5 ≥ O w I ° O N c _ z a 2 20 40 60 80 100 N Pumping Time (min) '0 0 Laidlaw Denver Regional Landfill (South) Recovery Tests Aucqust 20, 1991 Doty & Associates S-204 RECOVERY TEST S-204 was bailed twice on June 7, 1991, in order to develop the well. Approximately 24 . 9 gallons were removed from the well between 9: 33 am and 2 : 42 pm. Recovery of the water level in the well was then monitored for a period of 156 minutes. The recovery data are shown on the following tables -and figures. Analyses Analyses were performed using the Theis recovery method (Theis, 1935) , coupled with the Jacob straight line method (Cooper and Jacob, 1964) . The straight line match is shown on one of the following figures, yielding: Transmissivity = 2 . 4x10'4 ft2/min Assuming a storage coefficient of 0.001 (the water yielding material is a fully saturated sandstone approximately 12 . 2 feet thick) , then u = 0. 0002 at the end of the test and is higher at earlier times; u must be less than 0. 01 to meet the assumptions of the analysis. Therefore, the Theis/7acob analysis is generally applicable for this test. This result -was evaluated for reasonableness by performing a predictive analysis using the Theis recovery method. The Theis recovery method involves superposing an injection well on the withdrawal well at the time withdrawal ceased, and summing the drawdowns -from each in order to simulate the recovering water levels. The best match is shown on an attached figure; the match was obtained using the values al Transmissivity = 3x1O-4 ft2/min O Storage = 0. 001 O.a H-7 net."'" Laidlaw Denver Regional Landfill (South) Recovery Tests August 20, 1991 Doty & Associates Result The Theis match is reasonably adequate and the resulting hydraulic values, Conductivity = 1. 3x10-5 cm/s Storage = 0. 001 should be used as the result of this test. L a a T U N C 0 N C a H-8 Laidlaw Denver Regional Landfill (South) Recovery Tests August 20, 1991 Doty & Associates S-204 RECOVERY TEST DATA Date: 6/ 7/91 Static Depth to Water (ft) : 58 . 21 Bailing began: 9: 33 : 3 am Bailing ceased: 2 : 42 : 6 pm Duration of bailing (min) : 1-89 . 05 Volume removed (gals) : 24. 9 Flow rate (gpm) : . 13 Length of inflow (ft) : 12 .2 Material: Sandstone Depth to Time Water hrs min sec (feet) 2 : 43 : 30 101. 00 2 : 44 : 4 100. 90 2 : 44 : 45 100. 8-0 2 : 45: 24 100. 70 2 : 45: 2 100. 60 2 : 46: 46 100.50 2 : 47: 28 100.40 2 : 48: 7 100. 30 2 : 48 : 50 100. 20 2 : 49 : 33 100. 10 2 : 50: 17 100. 00 2 : 51: 3 99. 90 v 2 : 51: 48 99 . 810 2 : 52 : 38 99 .70 v 2 : 53 : 26 99 . 60 2 : 54 : 19 99 . 50 2 : 55: 9 99 . 410 2 : 56: 1 99. 30 2 : 56 : 56 99 . 20 2 : 57: 48 99 . 10 2 : 58 : 42 99 . 0D 3 : 0: 32 98 .80 3 : 2 : 34 9-8. 60 3 : 4: 34 98 .40 3 : 6: 44 98 . 20 3 : 8 : 50 98 . 00 H-9 Laidlaw Denver Regional Landfill (South) Recovery Tests August 20, 1991 Doty & Associates S-204 RECOVERY TEST DATA (continued) Depth to Time Water hrs min sec (feet) 3 : 12 : 11 97 .70 3 : 15: 44 97 .40 3 : 19 : 21 97 . 10 3 : 26: 44 96. 50 3 : 33 : 36 96. 00 3 : 43 : 32 95.50 3 : 58 : 7 95. 00 5: 18 : 18 93 . 40 L a a. u u a c O a v C L O. H-10 S- 204 RECOVERY DATA 4 6 0 - a 3 0 3 10 \ 0 r7") a' a 1. 0 12 w L N 0 0 N L a 14 0 50 100 150 200 Recovery Time (min) 0 0 S- 204 STRAIGHT LINE ANALYSIS 4 —9-- Data —*-- Straight Line 6 8 v p C 3 0 13 3 10 \ o L \ O g o a u O 12 u I ` i• N O : . o N • 14 0 .5 1 L5 2 2.5 U a Log (t/t') cks 0 a S- 204 RECOVERY MATCH T=3E-4 ft2/min; S=0.001; Q=0.0174 ft3/min 0 —8— Data --X— Predicted 4 a) 8 0 12 0 � 0 r I o a _ r 0 16 L N O 0 N 20n 0 50 100 150 200 Recovery Time (min) 0 0 Laidlaw Denver Regional Landfill (South) Recovery Tests August 20 , 1991 Doty & Associates S-205 RECOVERY TEST S-205 was bailed on June 6, 10 and 11, 1991, in order to develop the well. Approximately 6. 3 gallons were removed from the well between 1:44 and 2 : 48 pm, on June 10. Recovery of the water level in the well was monitored following the June 10 bailing for a period of 101 minutes. The recovery data are shown on the following tables and figures. Analyses Analyses were performed using the Theis recovery method (Theis, 1935) , coupled with the Jacob straight line method (Cooper and Jacob, 1964) . The straight line match is shown on one of the following figures, yielding: Transmissivity = 1.5x10-3 ft2/min Assuming a storage coefficient of 0. 1 (the water yielding material is a partially saturated coal Horizon approximately 2 .9 feet thick) , then u = 0. 02 at the end of the test and is higher at earlier times; u must be less than 0. 01 to meet the assumptions of the analysis. Therefore, the Theis/Jacob analysis is not strictly applicable for this test. This result was evaluated for reasonableness by performing a predictive analysis using the Theis recovery method. The Theis k recovery method involves superposing an injection well on the withdrawal well at the time withdrawal ceased, and summing the drawdowns from each in _order to simulate the recovering water levels. The best match is shown on an attached figure; the match was obtained using the values ° Transmissivity = 2x10'4 ft2/min Storage = 0. 1 H-14 Laidlaw Denver Regional Landfill (South) Recovery Tests August 20, 1991 Doty & Associates Result The Theis match is reasonably adequate and the resulting hydraulic values, Conductivity = 3 .5x10'5 cm/s Storage = 0. 1 should be used as the result of this test. a a 0 v u O 0 0 C 0 O 0 L n H-15 Laidlaw Denver Regional Landfill (South) Recovery Tests August 20, 1991 Doty & Associates S-205 RECOVERY TEST DATA Date: 6/10/91 Static Depth to Water (ft) : 35. 91 Bailing began: 1: 44: 25 Bailing ceased: 3 : 2 : 29 Duration of bailing (min) : 78. 07 Volume removed (gals) : 6. 3 Flow rate (gpm) : . 081 Length of inflow (ft) : 2 . 9 Material: Coal Depth to Time Water hrs min sec (feet) 3 : 3 : 17 43 . 40 3 : 3 : 56 43 . 30 3 : 4 : 42 43 . 20 3 : 5: 30 43 . 10 3 : 6: 17 43 . 00 3 : 7: 14 42 .90 3 : 8 : 4 42 .80 3 : 9 : 25 42 . 60 3 : 11: 27 42 . 40 3 : 13 : 5 42 . 20 3 : 14 : 46 42 . 00 3 : 16: 20 41. 80 3 : 18: 1 41. 60 3 : 19: 41 41. 40 3 : 21: 0 41. 20 3 : 22 : 21 41. 00 3 : 23 : 58 40.80 3 : 26: 9 40. 60 3 : 28 : 58 40. 40 a 0 3 : 31: 51 40. 20 3 : 35: 22 40. 00 3 : 40: 26 39 . 80 3 : 49 : 16 39. 60 4: 5: 21 39. 40 4 : 43 : 16 38. 77 H-16 S- 205 RECOVERY DATA 2 3 4J 4 a) a) 35 0 D o 0 6 c a o a E ;, v N 7 c o _ O iy Ul 8 0 50 100 150 Recovery Time (min) O 0 S- 205 STRAIGHT LINE ANALYSIS 0 —9— Data —x— Straight Line r. 3 a) C 3 0 0 0 6 a a E ,n I W L N c 0 o N a v c a 9 0 .5 1 1.5 2 Log (t/t') 0 0 S- 205 RECOVERY MATCH T=2E-4 ft2/min; S=0.1; Q=0.011 ft3/min 2 - —9— Data Predicted 3 4 4) U 4) � 5 C 3 0 -- 0 6 a L k 0 7 a T 0 d I- N p O 8 cn 9 0 50 100 150 0 Recovery Time (min) 0 0 Laidlaw Denver Regional Landfill (South) Recovery Tests August 20, 1991 Doty & Associates S-208 RECOVERY TEST S-208 was bailed on June 6, 10 and 12 , 1991, in order to develop the well. Approximately 1. 8 gallons were removed from the well between 1: 46 and 2 :20 pm, on June 6. Recovery of the water level in the well was monitored following the June 6 bailing for a period of 5, 384 minutes. The recovery data are shown on the following tables and figures. Analyses Analyses were performed using the Theis recovery method (Theis, 1935) , coupled with the Jacob straight line method (Cooper and Jacob, 1964) . The straight line match is shown on one of the following figures, yielding: Transmissivity = 1. 2x10'3 ft2/min Assuming a storage coefficient of 0. 001 (the water yielding material is a nearly fully saturated coal horizon approximately 1. 6 feet thick) , then u = 0. 0001 at the midpoint of the test; u must be less than 0. 01 to meet the assumptions of the analysis. Therefore, the Theis/Jacob analysis is apparently applicable for this test. This result was evaluated for reasonableness by performing a predictive analysis using the Theis recovery method. The Theis recovery method involves superposing an injection well on the withdrawal well at the time withdrawal ceased, and summing the $ drawdowns from each in order to simulate the recovering water levels. The best match is shown on an attached figure; the match was obtained using the values Transmissivity = 2 .5x10-6 ft2/min O Storage = 0. 001 H-20 Laidlaw Denver Regional Landfill (South) Recovery Tests August 20, 1991 Doty & Associates Result The best Theis match is not very good, indicating that the data violate the assumptions of the analyses. This is probably primarily due to wellbore storage effects (the formation is of low hydraulic conductivity and the flow to the well required to produce recovering water levels impose a significant continuing hydraulic stress on the formation. The true hydraulic conductivity is probably somewhat less than the Theis match result (7.9x10'8 cm/s) . It is considered likely that the following hydraulic values are generally appropriate for the subsurface material: Conductivity = 5x10-8 cm/s Storage = 0. 001 c4 0. u O 0 c 0 ac a H-21 Laidlaw Denver Regional Landfill (South) Recovery Tests August 20, 1991 Doty & Associates S-208 RECOVERY TEST DATA Date: 06/06/91 Static Depth to Water (ft) : 144 . 39 Bailing began: 0: 00: 00 Bailing ceased: 0: 34: 17 Duration of bailing (min) : 34. 28 Volume removed (gals) : 1.8 Flow rate (gpm) : . 053 Length of inflow (ft) : 1. 6 Material: Coal Depth to Elapsed Time Water hrs min sec (feet) 0: 34 : 57 148. 80 0: 36: 14 148. 70 0: 37 : 51 148. 60 0: 39 : 43 148. 50 0: 41: 49 148 . 40 0: 44: 39 148 . 30 0: 48: 17 148 .20 0: 52 : 57 148 . 10 0: 58: 35 148 . 00 1: 4: 26 147 .90 1: 12 : 10 147 .80 1: 21: 52 147 .70 1: 34: 37 147 . 60 a 2 : 10: 42 147 .40 3 : 20: 31 147 .21 17: 12 : 46 146. 60 22 : 1: 50 146. 48 d 26: 10: 0 146. 40 0 44: 34 : 10 145. 98 & 89: 10: 0 145. 24 H-22 • ~n9 .�&.vim',;, S- 208 RECOVERY DATA 0 1 02 C 0 3 3 \ 0 M L. \ 0 a o a 0 v 4 : U L N co N v v c n W 5 a 0 1000 2000 3000 4000 5000 6000 Recovery Time (min) 019 cks nr fle. - -. S-208 STRAIGHT LINE ANALYSIS 0 -9- Data -*- Straight Line 1 U) v 2 w r 3 0 D 3 3 • 0 L O O m a $ 0 4 N N c O o N a v C L 6 5 0 .05 .1 A5 .2 .25 .3 b9 (t/t') cki O yam... S- 208 RECOVERY MATCH • T=2.5E-5 ft2/min; S=0.001 ; Q=0.0071 ft3/min 0 -8- Data x -X— Predicted 1 4.1 0 ° 2 L 3 0 D 33 0 M L 0 4 kNol w 5 i 0 1000 2000 3000 4000 5000 6000 U Recovery Time (min) ckc (t.'i ,n r1.n Laidlaw Denver Regional Landfill (South) Recovery Tests August 20, 1991 Doty & Associates S-209 RECOVERY TEST S-209 was bailed on June 7 and 10, 1991, in order to develop the well. Approximately 19. 2 gallons were removed from the well between 10: 27 am and 12 : 05 pm, on June 10. Recovery of the water level in the well was monitored following the June 10 bailing for a period of 272 minutes. The recovery data are shown on the following tables and figures. Analyses Analyses were performed using the Theis recovery method (Theis, 1935) , coupled with the Jacob straight line method (Cooper and Jacob, 1964) . The straight line match is shown on one of the following figures, yielding: Transmissivity = 1. 6x10'3 ft2/min Assuming a storage coefficient of 0. 1 (the water yielding material is a fully saturated coal horizon approximately 2 . 5 feet thick) , then u = 0. 01 at the midpoint of the test; u must be less than 0. 01 to meet the assumptions of the analysis. Therefore, the Theis/Jacob analysis is not strictly applicable for this test. This result was evaluated for reasonableness by performing a predictive analysis using the Theis recovery method. The Theis recovery method involves superposing an injection well on the withdrawal well at the time withdrawal ceased, and summing the drawdowns from each in order to simulate the recovering water $ levels. The best match is shown on an attached figure; the match was obtained using the values u Transmissivity = 3 . 0x10"3 ft2/min 0 a Storage = 0. 1 H-26 Laidlaw Denver Regional Landfill (South) Recovery Tests August 20, 1991 Doty & Associates Result The Theis match is reasonably adequate and the resulting hydraulic values, Conductivity = 6. 1x10'4 cm/s Storage = 0. 1 should be used as the result of this test. L a u O d C I O H-27 Laidlaw Denver Regional Landfill (South) Recovery Tests August 20, 1991 Doty & Associates S-209 RECOVERY DATA Date: 6/10/91 Static Depth to Water (ft) : 81. 87 Bailing began: 10: 27 : 25 am Bailing ceased: 12 : 4: 58 pm Duration of bailing (min) : 97 .55 Volume removed (gals) : 19 .2 Flow rate (gpm) : .20 Length of inflow (ft) : 2 .5 Material: Coal Depth to Time Water hrs min sec (feet) 12 : 5: 46 83 .86 12 : 6: 21 83 .70 12 : 6: 57 83 . 60 12 : 8: 9 83 .50 12 : 10: 21 83 . 40 12 : 14 : 26 83 . 30 12 : 20: 5 83 . 20 13 : 34 : 10 82 . 67 16: 36: 45 82 . 31 k a 0 v U T U U C 0 3 C a H-28 n} S-209 RECOVERY DATA 0 .5 4-2 o 1 D 3 a I L M a 0 1.5 T L N c o o N a m c 2 0 50 100 150 200 250 300 Recovery Time (min) 0 0 S- 209 STRAIGHT LINE ANALYSIS 0 -B Data Straight Line .5 4-4- v C 0 1 U — 3 rn 0 M 0 � O — 1.5 -g Ln u o u E N O o c0 v n 2 0 .5 1 1.5 2 2.5 Log (t/t') cks } 0 0 S- 209 RECOVERY MATCH T=3E-3 ft2/min; S=0.1; Q=0.027 ft3/min 0 --8- Data —x— Predicted -1 3 2 0 -o 3 � o M L � 0 o a ' O T N y N O c N 0 E — c 4 0 50 100 150 200 250 300 Recovery Time (min) .45 } I Laidlaw Denver Regional Landfill (South) Recovery Tests August 20, 1991 Doty & Associates REFERENCES Cooper, H.H. , Jr. , and C.E. Jacob, 1964, A Generalized Graphical Method for Evaluating Formation Constants and Summarizing Well-Field History, Transactions of the American Geophysical Union, Volume 27, pp. 525-534 . Theis, C.V. , 1935, The Relation between the Lowering of the Piezometric Surface and the Rate and Duration of Discharge of a Well using Groundwater Storage, Transactions of the American Geophysical Union, Volume 16, pp. 519-524 . a n a a d U T U W L C b 7 H-32 2S Hello