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HomeMy WebLinkAbout1.25 Operations ManualOperation and Maintenance Plan PDC Energy Piceance Centralized Soil Treatment Facility OLSSON ASSOCIATES OA Project No. 011 -2627 760 Horizon Drive, Suite 102 1 Grand Junction, CO 81506 1 TEL 970.263.7800 1 FAX 970.263.7456 OPERATION AND MAINTENANCE COMPLIANCE PLAN Piceance Centralized Soil Treatment Facility Garfield County, Colorado Prepared by: PDC Energy, Inc. Denver, Colorado TABLE OF CONTENTS 1.0 OPERATOR INFORMATION 1 2.0 INTRODUCTION 2 2.1 Site Description 2 2.2 Geologic /Hydrogeologic Description 2 3.0 GENERAL OPERATING GUIDLINES 3 3.1 Allowable E &P Wastes — (REG. REQ.) 3 3.2 Facility Cell Rotation 4 3.3 Waste Preparation and Application 4 3.4 Tilling and Plowing 4 3.5 Soil Moisture 5 3.6 Run -on / Run -off 5 3.7 Fertilization 6 3.8 Soil Removal - (REG. REQ.) 6 3.8.1 Remediation Limits 6 3.8.2 Agency Approval 6 3.8.3 Beneficial Re -use of Remediated Soils 6 3.9 Site Security 7 3.10 Noise and Odor Mitigation 7 3.11 Inspections and Maintenance 8 3.12 Emergency Response 8 3.13 Winter Operations 8 4.0 SAMPLING AND MONITORING 8 4.1 Waste Sampling 8 4.1.1 Surface Soil (0" — 9 ", Biodegradation Zone) 8 4.1.2 Subsurface Soil (> 3', Unsaturated Zone) 9 4.1.3 Soil Sampling Required for Soil Removal / Beneficial Use 9 4.1.4 Groundwater 10 4.1.5 Emissions 10 5.0 RECORDKEEPING AND REPORTING 10 5.1 Recordkeeping 10 5.2 Reporting 11 6.0 PERMITS AND PERMIT CONDITIONS 11 6.1 Colorado Oil and Gas Conservation Commission (COGCC) 11 6.1.1 Performance Bond 11 6.1.2 Operating Permit 11 6.2 Colorado Department of Public Health and Environment (CDPHE), Air Pollution Control Division (APCD) 11 6.2.1 Construction Permit 12 6.2.2 Air Pollution Emission Notice (APEN) 12 6.3 Garfield County — Major Impact Review (LIR) 12 6.4 Surface Rights 12 7.0 REGULATORY MATRIX 14 Figure 1: Figure 2: Figure 3: Figure 4: Table 1: Table 2: Appendix A: Appendix B: Appendix C: Appendix D: Appendix E: List of Figures Facility Site Location — Topographic Facility Site Location — Aerial Facility Treatment Cell Layout Facility Treatment Cell — Sampling Grid List of Tables Nutrient Addition Worksheet COGCC Closure Limits for Remediated Soils (Table 910 -1) List of Appendices Facility Recordkeeping Forms COGCC Rules 907, 908, 909, 910 Permits ASTM Guidance Documents Typical Waste Profile Analytical Reports 1.0 OPERATOR INFORMATION Corporate Operator Information: PDC Energy, Inc. 1775 Sherman Street, Suite 3000 Denver, Colorado 80203 Telephone: (303) 860 -5800 Contact: Hayden Truscott Office: (303)- 860 -5806 Cell: (303)- 437 -0974 E -mail: htruscottpetd.com Local Operator Information: PDC Energy, Inc. 120 N. Railroad Avenue, Suite D Parachute, Colorado 81635 Telephone: (970) 285 -9606 Local Contact: Ed Winters Cell: (970) 319 -0498 E -mail: ewinters @petd.com Surface Owner Information: Puckett Land Company Air Quality Permit Information Permit Contact: Sarah Bartlett — Air Quality Engineer Email: sbartlett ©petd.com Facility Name: Piceance Centralized Soil Treatment Facility Construction Permit No.: 09GA1331 AIRS ID: 045/1879/001 Process Description: Treatment of exploration and production solid waste Facility Location: SW /4 Section 25, Township 6S, Range 95W, Garfield County, Colorado 1 2.0 INTRODUCTION PDC Energy, Inc. (PDC) will operate the Piceance Centralized Soil Treatment Facility (Facility), located in Garfield County, Colorado. This Operation and Maintenance Compliance Plan (O &M Plan) covers the proposed Facility identified in the Construction Permit Application as submitted to the Colorado Department of Public Health & Environment (CDPHE) / Air Pollution Control Division (APCD). This document has been prepared to outline the day -to -day operations and maintenance of this Centralized Exploration and Production (E &P) Waste Management Facility primarily regulated by the 900 series rules of the Colorado Oil and Gas Conservation Commission (COGCC) under the provisions of §34 -60- 103(4.5) of the Colorado Revised Statutes (C.R.S.). The soils to be treated on the Facility are E &P wastes exempt from hazardous regulation under Subtitle C of the Resource and Recovery Act (RCRA) of 1976. The guidance provided consists of regulatory requirements and recommended best practices. Regulatory requirements, including permit conditions, are specifically noted (REG. REQ.) in the text and summarized in Section 7.0 of this document. All other guidelines and recommendations are `best practices', subject to modification and improvement at the discretion of the Operator. This O &M Plan describes the methods and procedures that will be used to maintain and operate the soil treatment source, maintain required records, estimate air pollutant emissions, and demonstrate compliance with local, state and federal regulations as well as permit specific terms and conditions. 2.1 Site Description The Facility will be located in the southwest 1/4 of Section 25, Township 6 South, Range 95 West, in Garfield County, Colorado. The Facility will be located approximately 0.25 miles north of Interstate Highway 70 on parcel number 2173 - 352 -00 -016. Access to the Facility will be via a private road. The private road will be utilized via an existing permitted access that intersects with US Highway 6 & 24 approximately 3.25 miles east - northeast of the town of Parachute. 2.2 Geologic /Hydrogeologic Description According to available geologic information, surficial deposits within the area of the proposed site consist of young terrace and fan gravels of Quaternary Grand mesa (Qg) deposits. Grain size is typified by glacial and non - glacial pebble, cobble and boulder gravel within a sandy matrix. Grains are often imbricated and textural maturity ranges from moderately to well sorted, and subrounded to rounded grain surfaces. Parent material is derived from basalt and assorted sedimentary rocks from high topography to the north. Gradient within this formation typically varies from 50 feet to 100 feet per mile and averages five feet to 200 feet thick (Yeend and Donnell, 1960). Nearby water well boring Togs report these sediments to be approximately 70 feet thick in this area (Figure 1). The western portion of the proposed site sits on alluvial fan deposits from the drainage northeast of the Site. Alluvial fans commonly consist of silt, sand, and gravel, and can experience surface drainage constrained in either ephemeral stream channels or as sheet flow during high precipitation events. 2 Bedrock is comprised of the tertiary Wasatch Formation (Tw) consisting of red, gray, and purple to lavender shale and clay. The upper most member of the Wasatch Formation, the Shire Member, likely makes up the bedrock beneath the site, and is dominated by red claystone with minor fine to coarse grained sandstone lenses (Yeend and Donnell, 1960). Three water wells are located less than a mile east of the Site and are approximately along contour with the area of the proposed Site. Boring Togs for the wells report clay and sandstone gravels from 0 to 20 feet below ground surface (ft -bgs), red clay and sandstones from 20 to 48 ft -bgs, and pea size river gravel and sand from 48 to 67 ft -bgs. Bedrock was reported at approximately 70 ft -bgs, and is characterized by red sandstones, consistent with Wasatch Formation lithology. At the time of well completions (April 2004 and September 2004), groundwater was encountered at depths between 65 to 70 ft -bgs. Static depth to groundwater in the wells was reported between 55 to 60 ft -bgs. (Colorado Division of Water Resources; well permit numbers 75022 -F, 61348 -F, and 254154). The estimated groundwater flow direction is likely to be sub - parallel with the Colorado River, flowing south - southwest approximately 1500 feet from the proposed site. 3.0 GENERAL OPERATING GUIDLINES Land treatment or land application, is an above - ground remediation technology for impacted E &P waste that reduces concentrations of petroleum hydrocarbon constituents through natural biodegradation. For PDC's operations, this technology involves spreading impacted soils on the ground surface within the facility, shallow tilling to mix the soils, and stimulating aerobic microbial activity within the soils through aeration and the addition of fertilizers and moisture. The enhanced microbial activity will result in degradation of adsorbed petroleum hydrocarbon constituents through microbial respiration. Emissions of Volatile Organic Compounds (VOCs) and Hazardous Air Pollutants (HAPs) occur due to volatilization of the hydrocarbons from the Facility soils. Best management practices (BMPs) will be used to reduce emissions from the Facility. The Facility is subdivided into two remediation cells as shown in the attached Figure 3. Each cell will be monitored for contaminants as described in Section 4.0 of this document. When it has been demonstrated by analytical testing that treated soil complies with COGCC requirements for beneficial reuse, it is PDC's intention to recycle the soil elsewhere within its Piceance operations. Potential uses of the soil include access road construction, berm construction, or backfill for excavations at spill remediation sites. PDC's goal is to remediate certain wastes as they are produced, eliminating the need for disposal at landfill facilities. 3.1 Allowable E &P Wastes — (REG. REQ.) Material allowed at the Facility includes all wastes generated by and associated with PDC's primary field operations in the Piceance Field. These wastes are defined by §304 -60- 103(4.5) C.R.S. as wastes exempt from regulation as hazardous under Subtitle C of the Resource Conservation and Recovery Act (RCRA) of 1976, as amended. Allowable E &P wastes include: • Water based bentonitic drilling fluids and /or associated drill cuttings • Soil impacted by spills — produced water increases the potential for elevated sodium adsorption ratio (SAR) and electrical conductivity in soils. Treated 3 soils that exhibit elevated SAR and EC levels may be treated with gypsum, sulfur or other appropriate amendments. • Any other E &P waste directly attributable to and characteristic of, primary gas production activities. As noted in the bullet above, some `allowable' wastes are not recommended for the Facility. Wastes NOT allowed at the Facility include, but are not limited to: • Wastes contaminated by refined or processed materials, such as diesel, motor oil, lube oils, greases, or solvents. • Wastes generated by anyone other than PDC • Aerosol cans, light bulbs, batteries, or any other garbage not unique to an upstream gas producer and not qualifying as a waste exempt from hazardous regulation under Subtitle C of RCRA. 3.2 Facility Cell Rotation The Facility has been divided into two individual cells (Figure 3) varying in size from 1.97 acres to 4.70 acres. Depending on waste volumes to be treated in any given year, each cell can be managed as an independent unit or combined with an adjacent cell or cells and managed as a group. Subdividing the Facility into management cells will facilitate a rotation so each portion of the Facility will go through successive treatment stages. The overall intent is to stagger the phases so that some portion of the Facility is in a different phase at any given time. With appropriate project planning and budgeting, this staggered, phased approach should maximize the efficiency of Facility operations. 3.3 Waste Preparation and Application Prior to transport to the Facility, waste should be de- watered as much as possible. Wastes with high water content pose both technical and pragmatic challenges to Facility operations. The technical challenge stems from the fact that water associated with these wastes usually contains high concentrations of salts, inhibiting the effectiveness of the microbial degradation. The pragmatic challenge results from the difficultly of operating heavy equipment in excessively wet conditions. De- watered wastes will be transported to the Facility by end -dump trucks and placed on a specified remediation cell. The volume and type of each waste will be recorded in a Facility log book kept at the site and subsequently entered into an electronic waste log spreadsheet. Example recordkeeping forms are included in Appendix A. For operational and logistical reasons, wastes may be stockpiled in a staging area prior to application in a remediation cell. The waste will be applied to a depth of approximately 12 to 18 inches. The time elapsed between spreading and tilling will be documented for each application of waste (REG. REQ. per APCD Emissions Permit condition). The time between spreading and tilling will be operationally minimized to reduce VOC and HAP emissions. 3.4 Tilling and Plowing As noted above, the waste will be spread to a depth of 12 -18 inches and tilled periodically. Tilling serves two purposes — 1.) reducing VOC emissions and, 2.) aerating the soil. To ensure adequate oxygen exposure, the waste should not be tilled any 4 deeper than 12 -18 inches during the waste application processes. After the initial tilling, Facility cells in the "remediation" phase should be periodically shallow tilled during the active months (approximately April — October). The shallow tilling frequency should be at least monthly, and more often to enhance bioremediation. 3.5 Soil Moisture During the active remediation season, soil moisture should be maintained between five and twenty percent. Soil moisture levels above twenty percent displace oxygen and severely diminsh degradation rates. Soil moisture levels below five percent will limit microbial degradation, but less severely than levels above twenty percent. Due to the high altitude, generally low relative humidity and frequent high winds, soil moisture should be gauged often and adjustments made as appropriate. 3.6 Run -on / Run -off Run -on for the project will be controlled through the use of diversion berms and swales. Run -off for the project is controlled through the use of an onsite retention basin. On site conveyance utilizes sheet flow to either roadside ditches or diversion swales. Conveyance under drive areas includes CMP culverts. The project is designed in accordance with the COGCC rule stating, "Surface water diversion structures, including, but not limited to berms and ditches, shall be constructed to accommodate a one hundred (100) year, twenty -four (24) hour event. The facility shall be designed and constructed with a run -on control system to prevent flow onto the facility during peak discharge and a run -off control system to contain the water volume from a twenty -five (25) year, twenty -four (24) hour storm." The site is designed with a run -on diversion swale/ berm that convey the off -site run -on from the north to west and east around the site. Ultimately the stormwater will be conveyed via swales following the historic drainage path to the south. Stormwater within the site generally sheet flows from the northeast to the southwest. An internal roadway bisects the site from north to south. Roadside ditches will capture the stormwater and convey the on -site run -off to a retention basin located in the southwest corner of the site. Access points into each cell are provided. At these points drainage culverts will convey the stormwater under the access points. General design of the site is to prevent off -site stormwater from entering the site, while stormwater generated within the site is self- contained. The risks associated with stormwater run -on and run -off are mitigated by way of previously described methods. These methods are in conformance with COGCC rules. Drainage facilities associated with the site have been designed and the associated calculations can be found within the "Drainage Report, PDC Centralized Soil Treatment Facility, Garfield County, Colorado" prepared by Olsson Associates. The site is designed and will be operated to conform with the CDPHE General Construction Stormwater Permit #COR031735 and associated Stormwater Management Plan. 5 3.7 Fertilization As with all living things, the microbes that catalyze the degradation of hydrocarbons require a certain amount of micronutrients. Paramount among these are nitrogen and phosphorus. If the soil is deficient in these nutrients, soil supplements should be administered. Recommended nutrient levels are: • Nitrogen (soluble) — 50 — 200 ppm • Phosphorus - > 5 ppm • Gypsum /Sulfur — as needed dependent upon SAR and EC levels If waste loading on a particular cell is expected to be light, it is recommended that the Operator test nutrient levels at least bi- annually and exercise their best conservative judgment on the amount and timing of fertilizer application. If too little fertilizer is added the rate of bioremediation will be slower than optimum, however too much fertilizer can have toxic effects on the microbes. Therefore, under - fertilization is preferable to over - fertilization. If waste loading is expected to be high and high efficiency bioremediation is required for a quicker cycle time, then a more rigorous nutrient testing and soil amendment program is recommended. Periodic soil analysis for soluble nitrogen (ammonia nitrogen and nitrate nitrogen), and available phosphorus should be conducted and the results used to determine the amount of chemical fertilizer to be used. For highest efficiency, chemical fertilizers (rather than manure) are recommended so that quantities of nutrients added to the soil can be controlled more precisely. To estimate the amount of chemical fertilizer to be added, a Nutrient Addition Worksheet has been attached as Table 1. An excel worksheet with these calculations, Facility Nutrient Calcs.xls, is being provided with this documentation. 3.8 Soil Removal - (REG. REQ.) Reuse and recycling of remediated soils will be conducted according to the provisions of this written management plan per COGCC Rule 907 a.(3). 3.8.1 Remediation Limits Removing soil from the Facility for beneficial use requires that the treated soils meet the closure requirements as defined in COGCC Rules 909, 910, and Table 910 -1 (see Appendix B and Table 2). 3.8.2 Agency Approval Getting COGCC approval to remove soil from the Facility is a two -step process. a) Follow Centralized E &P Waste Management Facility permit requirements. b) Demonstrate compliance with the closure requirements listed in Table 2. See Section 4.1.4, Soil Sampling Required for Soil Removal. 3.8.3 Beneficial Re -use of Remediated Soils Once the soil in a Facility cell meets the closure requirements listed in Table 2 (see Soil Sampling for Soil Removal /Beneficial Re -use, Section 4.1.4), the 6 surface soil from that cell can be removed from the Facility and used for one of the following purposes within the Piceance Field: a) Fill dirt for drilling mud reserve pit closure in accordance with COGCC 900 Series rules b) Construction material of containment berms, dikes, or diversionary structures to control spills and / or storm water run -off. c) Road material for PDC lease roads within the Field. d) Fill dirt for construction sites. e) Post - construction contouring. f) Stockpiles reserved for one of the above listed uses. Whenever soil is removed from the Facility, documentation will be developed and maintained. That documentation should include: a) Soil analytical results demonstrating compliance with the COGCC closure limits prior to soil removal (see Section 4.1.4). b) Date of soil removal. c) Facility location (cell number) from which the soil originated d) Volume of soil removed and approximate depth of soil layer removed. e) Beneficial use (as outlined above), including location. If the soil is stockpiled for future beneficial use, then a log of the volumes, uses, and locations of the stockpiled soil should be maintained until removal. 3.9 Site Security Access to the Facility will be restricted by an eight (8) foot chain link fence and gate at the entrance. The gate shall be locked and any Facility activity must be approved through the local PDC Field Environmental and Safety Representative, Operations Supervisor, or other person specifically designated by the Operations Supervisor. (REG. REQ.) The Facility will be maintained with a perimeter fire lane at least ten (10) feet in width. The fire lane will be located within the perimeter berm. Normal operating hours will match the scheduled work shift(s) of the designated Facility Manager and typically from 7AM to 5PM on weekdays, however due to operating needs and project requirements, schedules may vary on an as- needed basis. 3.10 Noise and Odor Mitigation Due to the size and location of the Facility, noise mitigation is unnecessary except in the application of personal protective equipment (hearing protection) for personnel operating equipment. PDC will manage Facility operations in such a way that odors do not present an issue. If odors become an issue they will be aggressively mitigated by the tilling activities described above. 7 3.11 Inspections and Maintenance PDC has assigned one of the Parachute staff as the Facility Manager. That person is responsible for managing the day -to -day operations of the Facility and is responsible for periodic inspections and maintenance of equipment. Inspections will include all aspects of Facility operation as described in this O &M Plan. Routine and special maintenance will be performed as required. 3.12 Emergency Response Emergency response procedures for the Piceance Field (including the Centralized Soil Treatment Facility) are fully detailed in the Piceance Field Emergency Response Plan. 3.13 Winter Operations During winter months when the soil is snow covered and /or frozen, any waste material generated for Facility remediation will be stockpiled in a staging area. 4.0 SAMPLING AND MONITORING 4.1 Waste Sampling (REG. REQ.) — COGCC requires that for each type of waste to be treated a characteristic waste profile shall be completed. Waste profiles have been completed for hydrocarbon and produced water impacted soils — the most common type of wastes to be applied at the Facility (see attached reports as Appendix E). If an allowable waste that differs significantly in chemical or physical properties is applied to the Facility, then a waste profile shall be generated for that waste. The profile will include the parameters listed in the COGCC Table 910 -1 as a minimum. 4.1.1 Surface Soil (0" — 9 ", Biodegradation Zone) Pre - construction baseline soil samples have been collected and analyzed per the regulatory requirements for `active' cells plus the analyses required for closure (Table 2). This data will be used to establish baseline levels and facilitate long term planning for each cell. The requirements for annual testing should be conducted on each cell in the "Loading" or "Remediation" phases. (REG. REQ.) — The surface soil sampling and monitoring plan required to meet the permit requirements should include the following: • Annual sampling at the end of each remediation season • Ten random field samples from the `active' area, location determined using a random number table, mixed into a single composite lab sample. • Analyzed for: o TPH o pH o Salinity (Sodium Adsorption Ratio) o Other chemicals of concern 8 4.1.2 Subsurface Soil (> 3', Unsaturated Zone) Over time precipitation and water applications may cause petroleum hydrocarbons to leach into slightly deeper soil horizons. As a result, soils below the spreading and tilling depth of 12 -18 inches will be sampled periodically to determine any potential impacts to the undisturbed deeper soil horizons. (REG. REQ.) — The Subsurface soil sampling and monitoring plan required to meet the permit requirements should include the following: • Sample depth between 5 and 6 feet below grade • Annual sampling at the end of each remediation season • Ten random field samples from the `active' area, location determined using a random number table, mixed into a single composite lab sample. • Analyzed for: o Same parameters as the surface samples, plus o Nitrates 4.1.3 Soil Sampling Required for Soil Removal / Beneficial Use Once a cell is targeted for soil removal, certain procedures need to be employed to ensure compliance with all COGCC thresholds. Those procedures are: 1. Use the soil sampling procedures outlined in Section 4.1.1 of this document to establish the soil contaminant levels in the area /cell of interest. Use five (5) composited samples for each area /cell. 2. Estimate the total volume of soil to be removed based on surface area of cell and depth of removal. 3. Identify the area to be used for soil beneficial use (e.g., excavation backfill, post- construction contouring, berm material, etc.) 4. Collect soil samples to establish the background soil contaminant levels in the beneficial use area. Analyze for constituents of concern listed in COGCC Table 910 -1 (Table 2). 5. Use a mixing calculation to estimate the final "in- place" concentrations of all regulated contaminants, considering: a. Facility soil volumes b. Facility soil contaminant concentrations c. Estimated native soil volumes used to mix with the Facility soil volumes. d. Native soil background concentrations of selected contaminants. 6. If the estimated final "in- place" contaminant concentrations do no exceed 0.9 x COGCC Table 910 -1 thresholds (Table 2), then the soil removal and beneficial use placement is acceptable without further approval. 7. Variances to COGCC Table 910 -1 Thresholds a. If the native soil background concentrations at the beneficial use site exceed the COGCC Table 910 -1 thresholds (e.g., arsenic, barium), then the native soil background concentrations at each beneficial use site will be documented and maintained with the overall Facility compliance documentation maintained in the Piceance Field Office located in Parachute, Colorado. b. If the final "in- place" contaminant concentrations estimated by the mixing calculations described above do not exceed 1.2 x native soil background concentration, then the soil removal and beneficial use placement is permitted without further approval. 8. Final "in- place" soil sampling and analysis will be completed within 6 months of the project completion to demonstrate compliance with COGCC standards or the "variance" standard described in Section 4.1.4.7 9. Any variance from the procedures outlined in Section 4.0 will require prior approval from the COGCC. Additional guidance on sampling waste piles and representative sampling of wastes and contaminated media is provided in Appendix D — ASTM Guidance Documents. 4.1.4 Groundwater (REG. REQ.) — Three groundwater monitoring wells (two down gradient and one up gradient) will be installed to an anticipated total depth of 75 to 100 ft. -bgs once the Facility construction is completed. If water is found in any of the wells, a sample shall be taken and analyzed for (COGCC Rule 910 b.(4)C.): • BTEX (benzene, toluene, ethylbenzene, xylene) — EPA Method 8020 • Water analysis constituents detailed in the Colorado Oil and Gas Association's (COGA) Voluntary Baseline Sampling Program. 4.1.5 Emissions (REG. REQ.) — In 2012 an Emission Permit (09GA1331) was granted by the Air Pollution Control Division (APCD) of the Colorado Department of Public Health and Environment (CDPHE) for VOC emissions not to exceed206.2 tons per year. By permit condition, VOC emissions must be tracked on a rolling 12 -month basis. Emissions information shall be kept on a 12 -month rolling total basis so that compliance with the annual limits can be demonstrated. 5.0 RECORDKEEPING AND REPORTING 5.1 Recordkeeping (REG. REQ.) — Recordkeeping is required for two agencies — the CDPHE for VOC emissions estimates and the COGCC for annual reporting. Information required to estimate VOC emissions includes: • Volume, weight and type of waste applied • Application method (estimate of thickness applied) • Time between application and first tilling The COGCC requires records of the types and volumes of waste actually transported to the Facility, as well as a waste characterization profile of each type of waste handled at the Facility. The attached recordkeeping form (Appendix A) can be used to track the required and "best practice" data, which includes: • Date and time of waste application • Volume applied (and equivalent weight) 10 • Source of the waste • Type of waste • Facility cell used • Elapsed time between application and tilling • Application method (type of truck) and estimated thickness of application These records are managed and maintained by the Facility Manager and will be available for review by personnel from the COGCC and the APCD of the CDPHE upon request. 5.2 Reporting (REG. REQ.) — Effective April 1, 2009, each operator of an E &P Centralized Waste Management Facility is required to submit to the COGCC summarizing operations, including the types and volumes of waste actually handled at the Facility (COGCC Rule 908(f)). Data supplied in the attached recordkeeping format (Appendix A) can be used with a cover letter to comply with this requirement. 6.0 PERMITS AND PERMIT CONDITIONS 6.1 Colorado Oil and Gas Conservation Commission (COGCC) The Facility is classified as a Centralized E &P Waste Management Facility and is therefore regulated under the provisions of §34 -60- 103(4.5) of the Colorado Revised Statutes (C.R.S.) through the 900 series rules of the COGCC. A copy of the applicable 900 series rules is attached as Appendix B. The soil and groundwater sampling and analysis requirements are specified in these rules (as summarized above). 6.1.1 Performance Bond Effective July 1, 2009 (COGCC amended rules 704 and 908.g.), each operator is required to post a financial assurance bond in an amount equal to the estimated cost necessary to ensure proper reclamation, closure and abandonment of the Facility. On XXXXXXXX, PDC Energy, Inc. posted a Performance Bond in an amount approved by the COGCC. (Bond No. XXXXXXXXXXX). A copy of that bond is included in Appendix C. The bond remains in effect until released by the COGCC and therefore requires no renewal or additional action by PDC, with the exception of the requirements under Rules 908.e. and 908.f. 6.1.2 Operating Permit On XXXXXXXXXXX, the COGCC granted a final Facility Operation Permit (No. XXXXXX). A copy of that permit is included in Appendix C. The permit is valid until revoked or amended by the COGCC and therefore requires no renewal or additional action by PDC. 6.2 Colorado Department of Public Health and Environment (CDPHE), Air Pollution Control Division (APCD) The APCD regulates air emissions from the Facility through the Construction (Emission) Permit program for stationary sources. The conditions and regulations are outlined below. 11 6.2.1 Construction Permit In 2012 the APCD granted Initial approval for Facility emissions through Permit 09GA1331 (copy attached in Appendix C). The germane permit conditions include: • VOC emissions limited to 206.2 tons per year • Total Facility loading limited to approximately 3,400 tons per year • Emissions records to be kept and compliance demonstrated on a rolling 12- month basis. • Revised Air Pollution Emission Notice (APEN) be filed whenever a significant change in emissions occurs, relative to the last submitted APEN. APENs are to be updated every 5 years. 6.2.2 Air Pollution Emission Notice (APEN) An APEN was submitted with the original Construction Permit application in October 2009. An updated APEN is required every five (5) years, at a minimum. 6.3 Garfield County — Major Impact Review (LIR) Garfield County requires a LIR Permit for the Facility operation. At any time when the size or general operating procedures change, a new or amended LIR Permit may be required. The current LIR Permit ( #XXXXXX) is expected to be issued in XXX 2012. Copies of the LIR Permit approval letter and application documents are included in Appendix C. 6.4 Surface Rights Puckett Land Company is the surface owner at this location. Surface Owner: Puckett Land Company Address: 5460 S. Quebec Street, Greenwood Village, CO 80111 Phone: (303) 763 -1000 Fax: (303) 763 -1040 Contact Person: Eric R. Stearns The legal description of the site is as follows: PUCKETT LAND COMPANY GARFIELD COUNTY COLORADO RECEPTION NUMBER 804598 RECORDED JUNE 30TH, 2011 LEGAL DESCRIPTION BEGINNING AT THE SOUTHWEST CORNER OF SECTION 25, T6S, R95W, U.S.B. &M, 6TH PRINCIPAL MERIDIAN THENCE NOODEGREES55'6 "W 489.40' ALONG THE WEST SECTION LINE OF SECTION 25 TO THE TRUE POINT OF 12 BEGINNING, THENCE NOODEGREES55'06 "W 834.01' ALONG THE SAID WEST LINE, THENCE N89DEGREES19'53 "E 986.57', THENCE S49DEGREES12'41 "WEST 1289.12' TO THE POINT OF BEGINNING. BASIS OF BEARINGS IS A GPS OBSERVATION. CONTAINS 9.509 ACRES MORE OR LESS. The surface rights to the property were leased to PDC by terms of a Surface Lease Agreement, dated April 18th, 2012. 13 7.0 REGULATORY MATRIX Category Agency or Agencies Requirement Affirmative Compliance Action Wastes applied EPA, COGCC, CDPHE Restricted to E &P wastes defined as exempt from hazardous regulation under subtitle C of RCRA Site security, restrict and document waste application Operating Permit COGCC Valid Operating Permit; compliance with approved operating plan and 900 series rules Permit approved x/x /xxxx. Operator understanding of 900 Series rules (attached as Appendix B) Sampling and Monitoring Plan COGCC Documented in Sections 3.0 of this document Maintain records of required monitoring. Reporting COGCC Annual Report Summarizing Operations Submitted annually summarizing waste volumes and type Air Emissions APCD Valid Emissions Permit (09GA1331, initial approval 2/8/12). (Note — this permit needs to be pushed to Final Approval) Compliance with Permit Conditions, including: • Limit emissions to <206.2 tons / yr. • Recordkeeping to demonstrate compliance with emissions limit • Submit revised APEN when significant changes occur. Air Pollution Emission Notice APCD Revised APEN submitted every 5 years, if no significant changes Keep and meet schedule for submitting revised APENs Land Use Garfield County Commissioners Major Impact Review Permit (Permit XXXXX) New permit required whenever significant change in operation. Revision of COGCC Operating Permit or non - routine APEN would trigger new permit requirement 14 UGSG Topographic Map, Garfield County Legend ® Site Boundary Access Road Q 217335200016 (Area: 364.66 acres) Highway /Interstate Parcels County Roads 1 1 1 Miles 0 0.125 0.25 0.5 PROJECT NO 011 -2627 DRAWN BY Jenna Muh!ha. DATE'. 7/19/12 TOPOGRAPHIC MAP PICEANCE CENTRALIZED SOIL TREATMENT FACILITY PETROLEUM DEVELOPMENT CORPORATION O\.OLSSO N ASSOC LAT ES 826 21 -1/2 ROAD GRAND JUNCTION, CO 81505 TEL 970.263.7800 FAX 970.263.7456 FIGURE 1 Legend ® Site Boundary Access Road 217335200016 (Area: 364.66 acres) Highway /Interstate Parcels County Roads 0 0.125 0.25 Miles 0.5 s PROJECT NO „_262, DRAWN BY Jen. MublbacM1 DATE'. 7/19/12 AERIAL MAP PICEANCE CENTRALIZED SOIL TREATMENT FACILITY PETROLEUM DEVELOPMENT CORPORATION O\OLSSO N AS5OCtATES 826 21 -1/2 ROAD GRAND JUNCTION, CO 81505 TEL 970.263.7800 FAX 970.263.7456 FIGURE 2 X X X X X X X X X X / /7 ,/ / / \ \ N 1 " =40' 0' 20' 40' 80' SCALE IN FEET LEGEND - SECTION LINE EXISTING PIPELINES - EDGE OF EXISTING ROAD EXISTING POWER EXISTING FENCE PROPOSED CHAINLINK FENCE PROPOSED ACCESS ROAD CENTERLINE EDGE OF PROPOSED ACCESS ROAD DRAINAGE SWALE FLOWLINE - CELL BOUNDARY 4m N THIS OTE DOCUMENT HAS BEEN RELEASED BY OLSSON ASSOCIATES ONLY FOR REVIEW BY REGULATORY AGENCIES AND OTHER PROFESSIONALS, AND IS SUBJECT TO CHANGE. THIS DOCUMENT IS NOT TO BE USED FOR CONSTRUCTION. OLSSON ASSOCIATES ASSUMES NO RESPONSIBILITY FOR EXISTING UTILITY LOCATIONS (HORIZONTAL OR VERTICAL). THE EXISTING UTILITIES SHOWN ON THIS DRAWING HAVE BEEN PLOTTED FROM THE BEST AVAILABLE INFORMATION. IT IS HOWEVER THE RESPONSIBILITY OF THE CONTRACTOR TO FIELD VERIFY THE LOCATION OF ALL UTILITIES PRIOR TO THE COMMENCEMENT OF ANY CONSTRUCTION ACTIVITIES. REVISIONS DESCRIPTION REVISIONS FACILITY TREATMENT CELL LAYOUT !J % ~ J• _ cI 0 L"L L• L D_ F oz UW f - � Z W EL • 1- -J o• 0 2N W • W aU GARFIELD COUNTY, COLORADO dawn by: E0 checked by: WP approved by: LP QA/QC by: WP project no.: 011 -2627 drawing no.: 011.2621 SAMPLING GRICS.CWG date: 04 -10 -2012 FIGURE 3 ■ • • • • CELL #1 3.71 ACRES ) // // / / / 1 I r I 1 Q O m N w U 2 - / //' CELL #2 1.33 ACRES /� / / /' I // • / /// / ' / / • / / // / / /// • / / / • / / / / lam / / // / % / / / / z !/ / / !� / / / /7/Z o / / , • ' ,c\OP / /' 7 / ' � / / ' / G-5 / ��' / / RETENTION / POND ACCESS / / • / / RETENTION POND • / • 7 /' - / / / / z/ \ / / / / / /7 ,/ / / \ \ N 1 " =40' 0' 20' 40' 80' SCALE IN FEET LEGEND - SECTION LINE EXISTING PIPELINES - EDGE OF EXISTING ROAD EXISTING POWER EXISTING FENCE PROPOSED CHAINLINK FENCE PROPOSED ACCESS ROAD CENTERLINE EDGE OF PROPOSED ACCESS ROAD DRAINAGE SWALE FLOWLINE - CELL BOUNDARY 4m N THIS OTE DOCUMENT HAS BEEN RELEASED BY OLSSON ASSOCIATES ONLY FOR REVIEW BY REGULATORY AGENCIES AND OTHER PROFESSIONALS, AND IS SUBJECT TO CHANGE. THIS DOCUMENT IS NOT TO BE USED FOR CONSTRUCTION. OLSSON ASSOCIATES ASSUMES NO RESPONSIBILITY FOR EXISTING UTILITY LOCATIONS (HORIZONTAL OR VERTICAL). THE EXISTING UTILITIES SHOWN ON THIS DRAWING HAVE BEEN PLOTTED FROM THE BEST AVAILABLE INFORMATION. IT IS HOWEVER THE RESPONSIBILITY OF THE CONTRACTOR TO FIELD VERIFY THE LOCATION OF ALL UTILITIES PRIOR TO THE COMMENCEMENT OF ANY CONSTRUCTION ACTIVITIES. REVISIONS DESCRIPTION REVISIONS FACILITY TREATMENT CELL LAYOUT !J % ~ J• _ cI 0 L"L L• L D_ F oz UW f - � Z W EL • 1- -J o• 0 2N W • W aU GARFIELD COUNTY, COLORADO dawn by: E0 checked by: WP approved by: LP QA/QC by: WP project no.: 011 -2627 drawing no.: 011.2621 SAMPLING GRICS.CWG date: 04 -10 -2012 FIGURE 3 o � a`. 0< 0 0 w 00 X X X X X X X X X X X X X 1 -001 1 -002 1 -003 1 -004 1 -005 1 -006 1 -007 1 -008 1 -009 1 -010 1 -011 1 -012 1 -913 1 -014 1 -015 1 -016 1 -017 1 -018 1 -019 1 -020 1 -021 1 -022 1 -023 1 -024 1 -025 —027 1 -028 1 -029 1 -030 1 -031 1 -032 1 -033 1 -034 1 -035 1 -036 —037 1 -038 1 =039 1 -040 1 -041 1 -042 1 -043 1 -1044 1 -045 1 -046 1 -047 1 -048 1 -049 1 -050 1 -051 1 -053 1 -054 1 -055 1 -056 1 -057 1 -058 1 -059 1 -060 1 -061 1 -062 1 -063 1 -064 1 -066 1 -067 1 -068 1 -069 1 -070 1 -071 1 -072 1 -073 1 -074 1 -075 1 -076 1 -077 1-078 — 079 1 -080 1 -081 1 -082 1 -083 1 -084 1 -085 CELL #1 1 -086 1 -087 1 -088 1 -089 1 -090 1 - -0 1 -092 1 -093 1 -094 1 -095 1 -096 3.71 ACRES 1 -097 1 -098 1 -099 1 -100 1 -101 1 -102 1 -103 1- -104 — 105 1 -106 1 -107 1 -108 1 -109 1 -110 1 -112 1 -113 1 -114 1 -115 1 -116 1 -117 it 11 8 1 -119 1 -120 1 -121 1 -123 1 -124 1 -125 1 -126 1 -127 1 -128 1 -129 1 -130 1 -131 1 -12 2 1 -133 1 -134 1 -135 1 -136 1 -137 1 -138 1 -139 1 -140 1 -141 1 -142 1 -143 1 -144 11-1 -5 1 -146 1 -147 1 -148 1 -149 1 -150 1 -151 1 -152 1 -153 1 -154 1 -155 1 -156 1 -157 4- 2 -027 #2 2 -028 2 -029 2 -030 2 -031 „ 63/ / / / / / 2 -033 2 -034 1.33 2 -035 A 2 -036 / ' 1 -159 1 -160 1 -161 1 -162 1 -163 1 -164 1 -165 1 -166 1 -167 1 -168 / / 1 -171 1 -172 1 -173 1 -174 1 -175 1 -176 1 -177 1 -178 1 -179 —1 1 -182 1 -183 1 -184 1 -185 1 -186 1 -187 1 -188 1 -189 1 ,f90 1 -191 1 -192 1 -193 1 -194 1 -195 1-196 1 -197 RETENTION POND ACCESS RETENTION POND / / / / / / / / / rn w 0 z / / / / / X X X X X X X X X X X X 2 -001 2 -002 2 -003 2 -004 2 -005 2 -006 2 -007 2 -008 2 -009 2 -010 2 -011 2 -012 2 -013 2 -014 2 -015 2 -016 2 -017 2 -018 2 -019 2 -020 2-021 2 -023 2 -024 2 -025 2 -026 CEL 2 -027 #2 2 -028 2 -029 2 -030 2 -031 „ 63/ / / / / / 2 -033 2 -034 1.33 2 -035 A 2 -036 RES 2 -037 2 -038 2 -039 2 -040 A 2 0 / / / / / / // 2 -042 2 -043 2 -044 2 -045 2 -046 2 -047 2 -048 ' s-• / ,,,- 2 -050 2 -051 2 -052 2 -053 2 -054 2 -05A �� s•• r// / / 2 -057 2 -058 2 -059 2 -060 2 -0�'f �A / / / / /// — 2 -063 2 -064 2 -065 2 1d6. • ./ / / / / / / 2 -067 2 -068 2 s:• � / / 2 -070 �� / / / // / / / / / / / / / / / / /� /7 / / / / / / �/ /�/ / / // + / // / / / �� /7/ / / 77 /+ / �� �// /7 ,/ 7/ 7 / / / // / /7 / / / / / / /j N 1 " =40' 0' 20' 40' 80' SCALE IN FEET LEGEND — SECTION LINE EXISTING PIPELINES — EDGE OF EXISTING ROAD —. EXISTING POWER EXISTING FENCE PROPOSED CHAINLINK FENCE PROPOSED ACCESS ROAD CENTERLINE EDGE OF PROPOSED ACCESS ROAD DRAINAGE SWALE FLOWLINE — CELL BOUNDARY N THIS OTE DOCUMENT HAS BEEN RELEASED BY OLSSON ASSOCIATES ONLY FOR REVIEW BY REGULATORY AGENCIES AND OTHER PROFESSIONALS, AND IS SUBJECT TO CHANGE. THIS DOCUMENT IS NOT TO BE USED FOR CONSTRUCTION. OLSSON ASSOCIATES ASSUMES NO RESPONSIBILITY FOR EXISTING UTILITY LOCATIONS (HORIZONTAL OR VERTICAL). THE EXISTING UTILITIES SHOWN ON THIS DRAWING HAVE BEEN PLOTTED FROM THE BEST AVAILABLE INFORMATION. IT IS HOWEVER THE RESPONSIBILITY OF THE CONTRACTOR TO FIELD VERIFY THE LOCATION OF ALL UTILITIES PRIOR TO THE COMMENCEMENT OF ANY CONSTRUCTION ACTIVITIES. REVISIONS DESCRIPTION REVISIONS FACILITY TREATMENT CELL - SAMPLE GRID 5 % ~ to J• _ C L• L D_ F o W z U f - � Z W • W o -JLu Lu o• 0 W 201 W J W 0 GARFIELD COUNTY, COLORADO drawn by: 50 checked by: WP approved by: LP QA/QC by: WP project no.: 011 -2627 drawing no.: 111.2627 SAMPLING GRIGS.GWG date: 04 -10 -2012 FIGURE 4 Table 1 - PDC Soil Treatment Facility - Nutrient Addition Worksheet Example 6/22/2012 Line Nutrient Addition Worksheet (Example) Input cells Formula cells Constants Units (Line Units 1 Bulk density, soil 100.0 Ib /ft3 10 Sp. vol., bulk soil 0.01000 ft3 /Ib 11 Weight of 1 acre of soil, 12" depth 2178 tons Calculations Nutrient content, common fertilizers 2 Target soluble nutrient concentration 200 ppm (mg /kg) 12 Urea 46% by weight 3 Current soluble nutrient concentration (from analysis) ppm (mg /kg) 13 Ammonium nitrate 33% by weight 4 Additional soluble nutrient required = Line 2 - Line 3 150 ppm (mg /kg) 14 Diammonium phosphate 18% by weight 15 Ammonium sulfate 21% by weight 5 Fertilizer used urea • 16 Other 1% by weight _ 6 Required soluble nutrient, per acre =(Line 4 / 1,000,000) x Line 11 x 2,000 653 Ibs 7 Total weight of fertilizer required, per acre =Line 6 / Appropriate value from Lines 12 - 16 1,420 Ibs 8 Area to be fertilized = acres 9 Total weight of fertilizer required Line 7 x Line 8 4,545 Ibs Table 2 COGCC Closure Limits for Remediated Soils (910 -1) Contaminant of Concern Concentrations Organic Compounds in Soil TPH (total volatile and extractable petroleum hydrocarbons) 500 mg /kg Benzene 0.17 mg/kg2 Toluene 85 mg/kg2 Ethylbenzene 100 mg/kg2 Xylenes (total 175 mg/kg2 Acenaphthene 1,000 mg/kg2 Anthracene 1,000 mg/kg2 Benzo(A)anthracene 0.22 mg/kg2 Benzo(B)fluoranthene 0.22 mg/kg2 Benzo(K)fluoranthene 2.2 mg /kg2 Benzo(A)pyrene 0.022 mg/kg2 Chrysene 22 mg/kg2 Dibenzo(A,H)anthracene 0.022 mg/kg2 Fluoranthene 1,000 mg/kg2 Fluorene 1,000 mg/kg2 Indeno(1,2,3,C,D)pyrene 0.22 mg/kg2 Napthalene 23 mg/kg2 Pyrene 1,000 mg/kg2 Organic Compounds in Ground Water Benzene 5 uSg /I3 Toluene 560 to 1,000 ;if g/13 Ethylbenzene 700 P4g /I3 Xylenes (Total) 1,400 to 10,000 ;M g/13,4 Inorganics in Soils Electrical Conductivity (EC) <4 mmhos /cm or 2x background Sodium Adsorption Ratio (SAR) <125 pH 6 -9 Inorganics in Ground Water Total Dissolved Solids (TDS) <1.25 x background3 Chlorides <1.25 x background3 Sulfates <1.25 x background3 Metals in Soils Arsenic 0.39 mg/kg2 Barium (LDNR True Total Barium) 15,000 mg/kg2 Boron (Hot Water Soluble) 2 mg /13 Cadmium 70 mg /kg3,6 Chromium (111) 120,000 mg/kg2 Chromium (VI) 23 mg /kg2,6 Copper 3,100 mg/kg2 Lead (inorganic) 400 mg/kg2 Mercury 23 mg/kg2 Nickel (soluble salts) 1,600 mg /kg2,6 Selenium 390 mg /kg2,6 Silver 390 mg/kg2 Zinc 23,000 mg /kg2,6 Liquid Hydrocarbons in Soils and Ground Water Liquid hydrocarbons including condensate and oil Below detection level OPERATION AND MAINTENANCE COMPLIANCE PLAN Piceance Centralized Soil Treatment Facility Garfield County, Colorado APPENDIX A Prepared by: PDC Energy, Inc. Denver, Colorado Petroleum Development Corporation Piceance Soil Treatment Facility Input Recordkeeping Format Waste Tracking Date Time Waste Type Application Method BBLS YDS FT3 TONS Source Location Comments Transporter 4 Petroleum Development Corporation Piceance Soil Treatment Facility Maintenance Recordkeeping Format Maintenance Tracking Date Time Disking Depth Plowing Date Sampling Fertilizer Maintenance Hours Cell Location Comments PDC Representative OPERATION AND MAINTENANCE COMPLIANCE PLAN Piceance Centralized Soil Treatment Facility Garfield County, Colorado APPENDIX B Prepared by: PDC Energy, Inc. Denver, Colorado E&P WASTE MANAGEMENT 901. INTRODUCTION a. General. The rules and regulations of this series establish the permitting, construction, operating and closure requirements for pits, methods of E &P waste management, procedures for spill /release response and reporting, and sampling and analysis for remediation activities. The 900 Series rules are applicable only to E &P waste, as defined in § 34 -60- 103(4.5), C.R.S., or other solid waste where the Colorado Department Of Public Health And Environment has allowed remediation and oversight by the Commission. b. COGCC reporting forms. The reporting required by the rules and regulations of this series shall be made on forms provided by the Director. Alternate forms may be used where equivalent information is supplied and the format has been approved by the Director. c. Additional requirements. Whenever the Director has reasonable cause to believe that an operator, in the conduct of any oil or gas operation, is performing any act or practice which threatens to cause or causes a violation of Table 910 -1 and with consideration of water quality standards or classifications established by the Water Quality Control Commission ( "WQCC" ) for waters of the state, the Director may impose additional requirements, including but not limited to, sensitive area determination, sampling and analysis, remediation, monitoring, permitting and the establishment of points of compliance. Any action taken pursuant to this Rule shall comply with the provisions of Rules 324A. through D. and the 500 Series rules. d. Alternative compliance methods. Operators may propose for prior approval by the Director alternative methods for determining the extent of contamination, sampling and analysis, or alternative cleanup goals using points of compliance. e. Sensitive area determination. When the operator or Director has data that indicate an impact or threat of impact to ground water or surface water, the Director may require the operator to make a sensitive area determination and that determination shall be subject to the Director's approval. The sensitive area determination shall be made using appropriate geologic and hydrogeologic data to evaluate the potential for impact to ground water and surface water, such as appropriate percolation tests that demonstrate that seepage will not reach underlying ground water or waters of the State and impact current or future uses of these waters. Operators shall submit data evaluated and analysis used in the determination to the Director. f. Sensitive area operations. Operations in sensitive areas shall incorporate adequate measures and controls to prevent significant adverse environmental impacts and ensure compliance with the concentration levels in Table 910 -1, with consideration to WQCC standards and classifications. 902. PITS - GENERAL AND SPECIAL RULES a. Pits used for exploration and production of oil and gas shall be constructed and operated to protect public health, safety, and welfare and the environment, including soil, waters of the state, and wildlife, from significant adverse environmental, public health, or welfare impacts from E &P waste, except as permitted by applicable laws and regulations. b. Pits shall be constructed, monitored, and operated to provide for a minimum of two (2) feet of freeboard at all times between the top of the pit wall at its point of lowest elevation and 900 -1 As of May 30, 2011 the fluid level of the pit. A method of monitoring and maintaining freeboard shall be employed. Any unauthorized release of fluids from a pit shall be subject to the reporting requirements of Rule 906. c. Any accumulation of oil or condensate in a pit shall be removed within twenty -four (24) hours of discovery. Operators shall use skimming, steam cleaning of exposed liners, or other safe and legal methods as necessary to maintain pits in clean condition and to control hydrocarbon odors. Only de minimis amounts of hydrocarbons may be present unless the pit is specifically permitted for oil or condensate recovery or disposal use. A Form 15 pit permit may be revoked by the Director and the Director may require that the pit be closed if an operator repeatedly allows more than de minimis amounts of oil or condensate to accumulate in a pit. This requirement is not applicable to properly permitted and properly fenced, lined, and netted skim pits that are designed, constructed, and operated to prevent impacts to wildlife, including migratory birds. d. Where necessary to protect public health, safety and welfare or to prevent significant adverse environmental impacts resulting from access to a pit by wildlife, migratory birds, domestic animals, or members of the general public, operators shall install appropriate netting or fencing. e. Pits used for a period of no more than three (3) years, or more than three (3) years if the Director has issued a variance, for storage, recycling, reuse, treatment, or disposal of E &P waste or fresh water, as applicable, may be permitted in accordance with Rule 903 to service multiple wells, subject to Director approval. f. Unlined pits shall not be constructed on fill material. g. Except as allowed under Rule 904.a, unlined pits shall not be constructed in areas where pathways for communication with ground water or surface water are likely to exist. h. Produced water shall be treated in accordance with Rule 907 before being placed in a production pit. i. Operators shall utilize appropriate biocide treatments to control bacterial growth and related odors as needed. 903. PIT PERMITTING /REPORTING REQUIREMENTS a. An Earthen Pit Report/Permit, Form 15, shall be submitted to the Director for prior approval for the following pits: (1) All production pits. (2) Special purpose pits except those reported under Rule 903.b.(1) or Rule 903.b.(2). (3) Drilling pits designed for use with fluids containing hydrocarbon concentrations exceeding 10,000 ppm TPH or chloride concentrations at total well depth exceeding 15,000 ppm. (4) Multi -well pits containing produced water, drilling fluids, or completion fluids that will be recycled or reused, except where reuse consists only of moving drilling fluids from one (1) oil and gas location to another such location for reuse there. b. An Earthen Pit Report /Permit, Form 15, shall be submitted within thirty (30) calendar days after construction for the following: 900 -2 As of May 30, 2011 (1) Special purpose pits used in the initial phase of emergency response. (2) Flare pits where there is no risk of condensate accumulation. c. An Earthen Pit Report/Permit, Form 15, shall not be required for drilling pits using water -based bentonitic drilling fluids with concentrations of TPH and chloride below those referenced in Rule 903.a.(3). d. An Earthen Pit Report /Permit, Form 15, shall be completed in accordance with the instructions in Appendix I. Failure to complete the form in full may result in delay of approval or return of form. e. The Director shall endeavor to review any properly completed Earthen Pit Report /Permit, Form 15, within thirty (30) calendar days after receipt. In order to allow adequate time for pit permit review and approval, operators shall submit an Earthen Pit Report /Permit, Form 15, at the same time as the Application for Permit to Drill, Form 2, is submitted. The Director may condition permit approval upon compliance with additional terms, provisions, or requirements necessary to protect the waters of the state, public health, or the environment. 904. PIT LINING REQUIREMENTS AND SPECIFICATIONS a. Pits that were constructed before May 1, 2009 on federal land, or before April 1, 2009 on other land, shall comply with the rules in effect at the time of their construction. The following pits shall be lined if they are constructed on or after May 1, 2009 on federal land, or on or after April 1, 2009 on other land: (1) Drilling pits designed for use with fluids containing hydrocarbon concentrations exceeding 10,000 ppm TPH or chloride concentrations at total well depth exceeding 15,000 ppm. (2) Production pits, other than skim pits, unless the operator demonstrates to the Director's satisfaction that the quality of the produced water is equivalent to or better than that of the underlying groundwater or the operator can clearly demonstrate by substantial evidence, such as by appropriate percolation tests, that seepage will not reach the underlying aquifer or waters of the state at contamination levels in excess of applicable standards. Subject to Rule 901.c, this requirement shall not apply to such pits in Huerfano or Las Animas Counties constructed before May 1, 2011, or to such pits in Washington, Yuma, Logan, or Morgan counties constructed before May 1, 2013. (3) Special purpose pits, except emergency pits constructed during initial emergency response to spills /releases, or flare pits where there is no risk of condensate accumulation. (4) Skim pits. (5) Multi -well pits used to contain produced water, drilling fluids, or completion fluids that will be recycled or reused, except where reuse consists only of moving drilling fluids from one oil and gas location to another such location for reuse there. Subject to Rule 901.c, this requirement shall not apply to multi -well pits used to contain produced water in Huerfano or Las Animas Counties constructed before May 1, 2011, or to multi -well 900 -3 As of May 30, 2011 pits used to contain produced water in Washington, Yuma, Logan, or Morgan counties constructed before May 1, 2013. (6) Pits at centralized E &P waste management facilities and UIC facilities. b. The following specifications shall apply to all pits that are required to be lined: (1) Materials used in lining pits shall be of a synthetic material that is impervious, has high puncture and tear strength, has adequate elongation, and is resistant to deterioration by ultraviolet light, weathering, hydrocarbons, aqueous acids, alkali, fungi or other substances in the produced water. (2) All pit lining systems shall be designed, constructed, installed, and maintained in accordance with the manufacturers' specifications and good engineering practices. (3) Field seams must be installed and tested in accordance with manufacturer specifications and good engineering practices. Testing results must be maintained by the operator and provided to the Director upon request. c. The following specifications shall also apply to pits that are required to be lined, except those at centralized E &P waste management facilities, unless an oil and gas operator demonstrates to the satisfaction of the Director that a liner system offering equivalent protection to public health, safety, and welfare, including the environment and wildlife resources, will be used: (1) Liners shall have a minimum thickness of twenty -four (24) mils. The synthetic or fabricated liner shall cover the bottom and interior sides of the pit with the edges secured with at least a twelve (12) inch deep anchor trench around the pit perimeter. The anchor trench shall be designed to secure, and prevent slippage or destruction of, the liner materials. (2) The foundation for the liner shall be constructed with soil having a minimum thickness of twelve (12) inches after compaction covering the entire bottom and interior sides of the pit, and shall be constructed so that the hydraulic conductivity shall not exceed 1.0 x 10 -' cm /sec after testing and compaction. Compaction and permeability test results measured in the laboratory and field must be maintained by the operator and provided to the Director upon request. (3) As an alternative to the soil foundation described in Rule 904.c.(2), the foundation may be constructed with bedding material that exceeds a hydraulic conductivity of 1.0 x 10-' cm /sec, if a double synthetic liner system is used; however, the bottom and sides of the pit shall be padded with soil or synthetic matting type material and shall be free of sharp rocks or other material that are capable of puncturing the liner. Each synthetic liner shall have a minimum thickness of twenty -four (24) mils. d. The following specifications shall also apply to pits used at centralized E &P waste management facilities, unless an oil and gas operator demonstrates to the satisfaction of the Director that a liner system offering equivalent protection to public health, safety, and welfare, including the environment and wildlife resources, will be used: (1) Liners shall have a minimum thickness of sixty (60) mils. The synthetic or fabricated liner shall cover the bottom and interior sides of the pit with the edges secured with at least a twelve (12) inch deep anchor trench around the pit perimeter. The 900 -4 As of May 30, 2011 anchor trench shall be designed to secure, and prevent slippage or destruction of, the liner materials. (2) The foundation for the liner shall be constructed with soil having a minimum thickness of twenty -four (24) inches after compaction covering the entire bottom and interior sides of the pit, and shall be constructed so that the hydraulic conductivity shall not exceed 1.0 x 10-7 cm /sec after testing and compaction. Compaction and permeability test results measured in the laboratory and field must be maintained by the operator and provided to the Director upon request. (3) As an alternative to the soil foundation described in Rule 904.d.(2), a secondary liner consisting of a geosynthetic clay liner, which is a manufactured hydraulic barrier typically consisting of bentonite clay or other very low permeability material, supported by geotextiles or geomembranes, which are held together by needling, stitching, or chemical adhesives, may be used. e. In Sensitive Areas, the Director may require a leak detection system for the pit or other equivalent protective measures, including but not limited to, increased record - keeping requirements, monitoring systems, and underlying gravel fill sumps and lateral systems. In making such determination, the Director shall consider the surface and subsurface geology, the use and quality of potentially- affected ground water, the quality of the produced water, the hydraulic conductivity of the surrounding soils, the depth to ground water, the distance to surface water and water wells, and the type of liner. 905. CLOSURE OF PITS, AND BURIED OR PARTIALLY BURIED PRODUCED WATER VESSELS. a. Drilling pits shall be closed in accordance with the 1000 - Series Rules. b. Pits not used exclusively for drilling operations, buried or partially buried produced water vessels, and emergency pits shall be closed in accordance with an approved Site Investigation and Remediation Workplan, Form 27. The workplan shall be submitted for prior Director approval and shall include a description of the proposed investigation and remediation activities in accordance with Rule 909. Emergency pits shall be closed and remediated as soon as the initial phase of emergency response operations are complete or process upset conditions are controlled. (1) Operators shall ensure that soils and ground water meet the concentration levels of Table 910 -1. (2) Pit evacuation. Prior to backfilling and site reclamation, E &P waste shall be treated or disposed in accordance with Rule 907. (3) Liners shall be disposed as follows: A. Synthetic liner disposal. Liner material shall be removed and disposed in accordance with applicable legal requirements for solid waste disposal. B. Constructed soil liners. Constructed soil liner material may be removed for treatment or disposal, or, where left in place, the material shall be ripped and mixed with native soils in a manner to alleviate compaction and prevent an impermeable barrier to infiltration and ground water flow and shall meet soil standards listed in Table 910 -1. 900 -5 As of May 30, 2011 (4) Soil beneath the low point of the pit must be sampled to verify no leakage of the managed fluids. Soil left in place shall meet the standards listed in Table 910 -1. c. Discovery of a spill /release during closure. When a spill /release is discovered during closure operations, operators shall report the spill /release on the Spill /Release Report, Form 19, in accordance with Rule 906. Leaking pits and buried or partially buried produced water vessels shall be closed and remediated in accordance with Rules 909. and 910. d. Unlined drilling pits. Unlined drilling pits shall be closed and reclaimed in accordance with the 1000 Series rules and operators shall ensure that soils and ground water meet the concentration levels in Table 910 -1. 906. SPILLS AND RELEASES a. General. Spills /releases of E &P waste, including produced fluids, shall be controlled and contained immediately upon discovery to protect the environment, public health, safety, and welfare, and wildlife resources. Impacts resulting from spills /releases shall be investigated and cleaned up as soon as practicable. The Director may require additional activities to prevent or mitigate threatened or actual significant adverse environmental impacts on any air, water, soil or biological resource, or to the extent necessary to ensure compliance with the concentration levels in Table 910 -1, with consideration to WQCC ground water standards and classifications. b. Reportable spills and reporting requirements for spills /releases. (1) Spills /releases of E &P waste or produced fluid exceeding five (5) barrels, including those contained within lined or unlined berms, shall be reported on COGCC Spill /Release Report, Form 19. (2) Spills /releases which exceed twenty (20) barrels of an E &P waste shall be reported on COGCC Spill /Release Report, Form 19, and shall also be verbally reported to the Director as soon as practicable, but not more than twenty -four (24) hours after discovery. (3) Spills /releases of any size which impact or threaten to impact any waters of the state, residence or occupied structure, livestock, or public byway shall be reported on COGCC Spill /Release Report, Form 19, and shall also be verbally reported to the Director as soon as practicable, but not more than twenty -four (24) hours, after discovery. (4) Spills /releases of any size which impact or threaten to impact any surface water supply area shall be reported to the Director and to the Environmental Release /Incident Report Hotline (1- 877 - 518 - 5608). Spills and releases that impact or threaten a surface water intake shall be verbally reported to the emergency contact for that facility immediately after discovery. (5) For all reportable spills, operators shall submit a Spill /Release Report, Form 19, within ten (10) days after discovery. An 8 1/2 x 11 inch topographic map showing the governmental section and location of the spill shall be included. Such report shall also include information relating to initial mitigation, site investigation, and remediation. The Director may require additional information. 900 -6 As of May 30, 2011 (6) Chemical spills and releases shall be reported in accordance with applicable state and federal laws, including the Emergency Planning and Community Right -to- Know Act, the Comprehensive Environmental Response, Compensation, and Liability Act, the Oil Pollution Act, and the Clean Water Act, as applicable. c. Surface owner notification and consultation. The operator shall notify the affected surface owner or the surface owner's appointed tenant of reportable spills as soon as practicable, but not more than twenty -four (24) hours, after discovery. The operator also shall make good faith efforts to notify and consult with the affected surface owner, or the surface owner's appointed tenant, prior to commencing operations to remediate E &P waste from a spill /release in an area not being utilized for oil and gas operations. d. Remediation of spills /releases. When threatened or actual significant adverse environmental impacts on any air, water, soil or other environmental resource from a spill /release exists or when necessary to ensure compliance with the concentration levels in Table 910 -1, with consideration to WQCC ground water standards and classifications, the Director may require operators to submit a Site Investigation and Remediation Workplan, Form 27. Such spills /releases shall be remediated in accordance with Rules 909. and 910. e. Spill /release prevention. (1) Secondary containment. Secondary containment that was constructed before May 1, 2009 on federal land, or before April 1, 2009 on other land, shall comply with the rules in effect at the time of construction. Secondary containment constructed on or after May 1, 2009 on federal land, or on or after April 1, 2009 on other land shall be constructed or installed around all tanks containing oil, condensate, or produced water with greater than 3,500 milligrams per liter (mg /I) total dissolved solids (TDS) and shall be sufficient to contain the contents of the largest single tank and sufficient freeboard to contain precipitation. Secondary containment structures shall be sufficiently impervious to contain discharged material. Operators are also subject to tank and containment requirements under Rules 603. and 604. This requirement shall not apply to water tanks with a capacity of fifty (50) barrels or less. (2) Spill /release evaluation. Operators shall determine the cause of a spill /release, and, to the extent practicable, shall implement measures to prevent spills /releases due to similar causes in the future. For reportable spills, operators shall submit this information to the Director on the Spill /Release Report, Form 19, within ten (10) days after discovery of the spill /release. 907. MANAGEMENT OF E &P WASTE a. General requirements. (1) Operator obligations. Operators shall ensure that E &P waste is properly stored, handled, transported, treated, recycled, or disposed to prevent threatened or actual significant adverse environmental impacts to air, water, soil or biological resources or to the extent necessary to ensure compliance with the concentration levels in Table 910 -1, with consideration to WQCC ground water standards and classifications. (2) E &P waste management activities shall be conducted, and facilities constructed and operated, to protect the waters of the state from significant adverse environmental impacts from E &P waste, except as permitted by applicable laws and regulations. 900 -7 As of May 30, 2011 (3) Reuse and recycling. To encourage and promote waste minimization, operators may propose plans for managing E &P waste through beneficial use, reuse, and recycling by submitting a written management plan to the Director for approval on a Sundry Notice, Form 4, if applicable. Such plans shall describe, at a minimum, the type(s) of waste, the proposed use of the waste, method of waste treatment, product quality assurance, and shall include a copy of any certification or authorization that may be required by other laws and regulations. The Director may require additional information. b. Waste transportation. (1) E &P waste, when transported off -site within Colorado for treatment or disposal, shall be transported to facilities authorized by the Director or waste disposal facilities approved to receive E &P waste by the Colorado Department of Public Health and Environment. When transported to facilities outside of Colorado for treatment or disposal, E &P waste shall be transported to facilities authorized and permitted by the appropriate regulatory agency in the receiving state. (2) Waste generator requirements. Generators of E &P waste that is transported off - site shall maintain, for not less than five (5) years, copies of each invoice, bill, or ticket and such other records as necessary to document the following requirements A through F: A. The date of the transport; B. The identity of the waste generator; C. The identity of the waste transporter; D. The location of the waste pickup site; E. The type and volume of waste; and F. The name and location of the treatment or disposal site. Such records shall be signed by the transporter, made available for inspection by the Director during normal business hours, and copies thereof shall be furnished to the Director upon request. c. Produced water. (1) Treatment of produced water. Produced water shall be treated prior to placement in a production pit to prevent crude oil and condensate from entering the pit. (2) Produced water disposal. Produced water may be disposed as follows: A. Injection into a Class 11 well, permitted in accordance with Rule 325.; B. Evaporation /percolation in a properly permitted pit; C. Disposal at permitted commercial facilities; D. Disposal by roadspreading on lease roads outside sensitive areas for produced waters with less than 3,500 mg /I TDS when authorized by the surface owner. Roadspreading of produced waters shall not impact 900 -8 As of May 30, 2011 (3) waters of the state, shall not result in pooling or runoff, and the adjacent soils shall meet the concentration levels in Table 910 -1. Flowback fluids shall not be used for dust suppression. E. Discharging into state waters, in accordance with the Water Quality Control Act and the rules and regulations promulgated thereunder. Operators shall provide the Colorado discharge permit number, latitude and longitude coordinates, in accordance with Rule 215.f, of the discharge outfall, and sources of produced water on a Source of Produced Water for Disposal, Form 26, and shall include a U.S.G.S. topographic map showing the location of the discharge outfall. ii. Produced water discharged pursuant to this subsection (2).E. may be put to beneficial use in accordance with applicable state statutes and regulations governing the use and administration of water. F. Evaporation in a properly lined pit at a centralized E &P waste management facility permitted in accordance with Rule 908. Produced water reuse and recycling. Produced water may be reused for enhanced recovery, drilling, and other approved uses in a manner consistent with existing water rights and in consideration of water quality standards and classifications established by the WQCC for waters of the state, or any point of compliance established by the Director pursuant to Rule 324D. (4) Mitigation. Water produced during operation of an oil or gas well may be used to provide an alternative domestic water supply to surface owners within the oil or gas field, in accordance with all applicable laws, including, but not limited to, obtaining the necessary approvals from the WQCD for constructing a new "waterworks," as defined by Section 25- 1- 107(1)(X)(II)(A), C.R.S. Any produced water not so used shall be disposed of in accordance with subsection (2) or (3). Providing produced water for domestic use within the meaning of this subsection (4) shall not constitute an admission by the operator that the well is dewatering or impacting any existing water well. The water produced shall be to the benefit of the surface owner within the oil and gas field and may not be sold for profit or traded. d. Drilling fluids. (1) Recycling and reuse. Drilling pit contents may be recycled to another drilling pit for reuse consistent with Rule 903. (2) Treatment and disposal. Drilling fluids may be treated or disposed as follows: A. Injection into a Class II well permitted in accordance with Rule 325; B. Disposal at a commercial solid waste disposal facility; or C. Land treatment or land application at a centralized E &P waste management facility permitted in accordance with Rule 908. (3) Additional authorized disposal of water -based bentonitic drilling fluids. Water - based bentonitic drilling fluids may be disposed as follows: 900 -9 As of May 30, 2011 A. Drying and burial in pits on non -crop land. The resulting concentrations shall not exceed the concentration levels in Table 910 -1, below; or B. Land application as follows: i. Applicability. Acceptable methods of land application include, but are not limited to, production facility construction and maintenance, and lease road maintenance. ii. Land application requirements. The average thickness of water - based bentonitic drilling fluid waste applied shall be no more than three (3) inches prior to incorporation. The waste shall be applied to prevent ponding or erosion and shall be incorporated as a beneficial amendment into the native soils within ten (10) days of application. The resulting concentrations shall not exceed those in Table 910 -1. iii. Surface owner approval. Operators shall obtain written authorization from the surface owner prior to land application of water -based bentonitic drilling fluids. iv. Operator obligations. Operators shall maintain a record of the source, the volume, and the location where the land application of the water -based bentonitic drilling fluid occurred. Upon the Director's written request, this information shall be provided within five (5) business days, in a format readily reviewable by the Director. Operators with control and authority over the wells from which the water -based bentonitic drilling fluid wastes are obtained retain responsibility for the land application operation, and shall diligently cooperate with the Director in responding to complaints regarding land application of water -based bentonitic drilling fluids. v. Approval. Prior Director approval is not required for reuse of water - based bentonitic drilling fluids for land application as a soil amendment. e. Oily waste. Oily waste includes those materials containing crude oil, condensate or other E &P waste, such as soil, frac sand, drilling fluids, and pit sludge that contain hydrocarbons. (1) Oily waste may be treated or disposed as follows: A. Disposal at a commercial solid waste disposal facility; B. Land treatment onsite; or C. Land treatment at a centralized E &P waste management facility permitted in accordance with Rule 908. (2) Land treatment requirements: A. Free oil shall be removed from the oily waste prior to land treatment. B. Oily waste shall be spread evenly to prevent pooling, ponding, or runoff. 900 -10 As of May 30, 2011 C. Contamination of stormwater runoff, ground water, or surface water shall be prevented. D. Biodegradation shall be enhanced by disking, tilling, aerating, or addition of nutrients, microbes, water or other amendments, as appropriate. E. Land - treated oily waste incorporated in place or beneficially reused shall not exceed the concentrations in Table 910 -1. F. When a threatened or significant adverse environmental impact from onsite land treatment exists, operators shall submit a Site Investigation and Remediation Workplan, Form 27, for approval by the Director. Treatment shall thereafter be completed in accordance with the workplan and Rules 909. and 910. G. When land treatment occurs in an area not being utilized for oil and gas operations, operators shall obtain prior written surface owner approval. f. Other E &P Waste. Other E &P waste such as workover fluids, tank bottoms, pigging wastes from gathering and flow lines, and natural gas gathering, processing, and storage wastes may be treated or disposed of as follows: (1) Disposal at a commercial solid waste disposal facility; (2) Treatment at a centralized E &P waste management facility permitted in accordance with Rule 908; (3) Injection into a Class II injection well permitted in accordance with Rule 325; or (4) An alternative method proposed in a waste management plan in accordance with rule 907.a.(3) and approved by the Director. 907A. MANAGEMENT OF NON -E &P WASTE a. Certain wastes generated by oil and gas - related activities are non -E &P wastes and are not exempt from regulation as solid or hazardous wastes. These wastes need to be properly identified and disposed of in accordance with state and federal regulations. b. Certain wastes generated by oil and gas - related activities can either be E &P wastes or non - E&P wastes depending on the circumstances of their generation. c. The hazardous waste regulations require that a hazardous waste determination be made for any non -E &P solid waste. Hazardous wastes require storage, treatment, and disposal practices in accordance with 6 C.C.R. 1007 -3. All non - hazardous /non -E &P wastes are considered solid waste which require storage, treatment, and disposal in accordance with 6 C.C.R. 1007 -2. 908. CENTRALIZED E &P WASTE MANAGEMENT FACILITIES a. Applicability. Operators may establish non - commercial, centralized E &P waste management facilities for the treatment, disposal, recycling or beneficial reuse of E &P waste. This rule applies only to non - commercial facilities, which means the operator does not represent itself as providing E &P waste management services to third parties, except as part of a unitized area or joint operating agreement or in response to an emergency. Centralized 900 -11 As of May 30, 2011 facilities may include components such as land treatment or land application sites, pits, and recycling equipment. b. Permit requirements. Before any person shall commence construction of a centralized E &P waste management facility, such person shall file with the Director an application on Form 28 and pay a filing and service fee established by the Commission (see Appendix 111), and obtain the Director's approval. The application shall contain the following: (1) The name, address, phone and fax number of the operator, and a designated contact person. (2) The name, address, and phone number of the surface owner of the site, if not the operator, and the written authorization of such surface owner. (3) The legal description of the site. (4) A general topographic, geologic, and hydrologic description of the site, including immediately adjacent land uses, a topographic map of a scale no less than 1:24,000 showing the location, and the average annual precipitation and evaporation rates at the site. (5) Centralized facility siting requirements. A. A site plan showing drainage patterns and any diversion or containment structures, and facilities such as roads, fencing, tanks, pits, buildings, and other construction details. B. Scaled drawings of entire sections containing the proposed facility. The field measured distances from the nearer north or south and nearer east or west section lines shall be measured at ninety (90) degrees from said section lines to facility boundaries and referenced on the drawing. A survey shall be provided including a complete description of established monuments or collateral evidence found and all aliquot corners. C. The facility shall be designed to control public access, prevent unauthorized vehicular traffic, provide for site security both during and after operating hours, and prevent illegal dumping of wastes. Appropriate measures shall also be implemented to prevent access to the centralized facility by wildlife or domestic animals. D. Centralized facilities shall have a fire lane of at least ten (10) feet in width around the active treatment areas and within the perimeter fence. In addition, a buffer zone of at least ten (10) feet shall be maintained within the perimeter fire lane. E. Surface water diversion structures, including, but not limited to, berms and ditches, shall be constructed to accommodate a one hundred (100) year, twenty four (24) hour event. The facility shall be designed and constructed with a run -on control system to prevent flow onto the facility during peak discharge and a run -off control system to contain the water volume from a twenty -five (25) year, twenty -four (24) hour storm. (6) Waste profile. For each type of waste, the amounts to be received and managed by the facility shall be estimated on a monthly average basis. For each waste type to be treated, a characteristic waste profile shall be completed. 900 -12 As of May 30, 2011 (7) Facility design and engineering. Facility design and engineering data, including plans and elevations, design basis, calculations, and process description. A. Geologic data, including, but not limited to: i. Type and thickness of unconsolidated soils; ii. Type and thickness of consolidated bedrock, if applicable; iii. Local and regional geologic structures; and iv. Any geologic hazards that may affect the design and operation of the facility. B. Hydrologic data, including, but not limited to: i. Surface water features within two (2) miles; ii. Depth to shallow ground water and major aquifers; iii. Water wells within one (1) mile of the site boundary and well depth, depth to water, screened intervals, yields, and aquifer name; iv. Hydrologic properties of shallow ground water and major aquifers including flow direction, flow rate, and potentiometric surface; v. Site location in relation to the floodplain of nearby surface water features; vi. Existing quality of shallow ground water; and vii. An evaluation of the potential for impacts to nearby surface water and ground water. C. Engineering data, including, but not limited to: i. Type and quantity of material required for use as a liner, including design components; ii. Location and depth of cut for liners; iii. Location, dimensions, and grades of all surface water diversion structures; iv. Location and dimensions of all surface water containment structures; and v. Location of all proposed facility structures and access roads. (8) Operating plan. An operating plan, including, but not limited to: A. A detailed description of the method of treatment, loading rates, and application of nutrients and soil amendments; B. Dust and moisture control; 900 -13 As of May 30, 2011 C. Sampling; D. Inspection and maintenance; E. Emergency response; F. Record - keeping; G. Site security; H. Hours of operation; I. Noise and odor mitigation; and J. Final disposition of waste. Where treated waste will be beneficially reused, a description of reuse and method of product quality assurance shall be included. (9) Ground water monitoring. A. Water Wells. Water samples shall be collected from water wells known to the operator or registered with the Colorado State Engineer within a one (1) mile radius of the proposed facility and shall be analyzed to establish baseline water quality. Analytical parameters shall be selected based upon the proposed waste stream and shall include, at a minimum, all major cations and anions, total dissolved solids, iron and manganese, nutrients (nitrates, nitrites, selenium), benzene, toluene, ethylbenzene, xylenes, pH, and specific conductance. Operators shall use reasonable good faith efforts to identify and obtain access to such water wells for the purpose of collecting water samples. If access cannot be obtained, then the operator shall notify the Director of the wells for which access was not obtained and sampling of such wells by the operator shall not be required. Not conducting sampling because access to water wells cannot be obtained shall not be grounds for denial of the proposed facility. Copies of all test results described above shall be provided to the Director and the water well owner within three (3) months of collecting the samples. Laboratory results shall also be submitted to the Director in an electronic data deliverable format. B. Site - specific monitoring wells. i. Where applicable, the Director shall require ground water monitoring to ensure compliance with the concentration levels in Table 910- 1 and WQCC standards and classifications by establishing points of compliance, unless an oil and gas operator demonstrates to the satisfaction of the Director that an alternative method offering equivalent protection of public health, safety, and welfare, including the environment and wildlife resources, can be employed and provided the operator employs a dual liner with a leak detection system that provides for immediate leak detection from the uppermost liner. All monitoring well construction must be completed in accordance with the 900 -14 As of May 30, 2011 State Engineer's regulations on well construction, "Water Well Construction Rules" (2 C.C.R. 402 -2). ii. Where monitoring is required, the direction of flow, ground water gradient and quality of water shall be established by the installation of a minimum of three (3) monitor wells, including an up- gradient well and two (2) down - gradient wells that will serve as points of compliance, or other methods authorized by the Director. (10) Surface water monitoring. Where applicable, the Director shall require baseline and periodic surface water monitoring to ensure compliance with WQCC surface water standards and classifications. Operators shall use reasonable good faith efforts to obtain access to such surface water for the purpose of collecting water samples. If access cannot be obtained, then the operator shall notify the Director of the surface water for which access was not obtained and sampling of such surface water by the operator shall not be required. Not conducting sampling because access to surface water cannot be obtained shall not be grounds for denial of the proposed facility. (11) Contingency plan. A contingency plan that describes the emergency response operations for the facility, 24 -hour contact information for the person who has authority to initiate emergency response actions, and an outline of responsibilities under the joint operating agreement regarding maintenance, closure, and monitoring of the facility. c. Permit approval. The Director shall endeavor to approve or deny the properly completed permit within thirty (30) days after receipt and may condition permit approval as necessary to prevent any threatened or actual significant adverse environmental impact on air, water, soil or biological resources or to the extent necessary to ensure compliance with the concentration levels in Table 910 -1, with consideration to WQCC ground water standards and classifications. d. Financial assurance. The operator of a centralized E &P waste management facility shall submit for the Director's approval such financial assurance as required by Rule 704. prior to issuance of the operating permit. e. Facility modifications. Throughout the life of the facility the operator shall submit proposed modifications to the facility design, operating plan, permit data, or permit conditions to the Director for prior approval. f. Annual permit review. To ensure compliance with permit conditions and the 900 Series rules, the facility permit shall be subject to an annual review by the Director. To facilitate this review, the operator shall submit an annual report summarizing operations, including the types and volumes of waste actually handled at the facility. The Director may require additional information. g. Closure. (1) Preliminary closure plan. A general preliminary plan for closure shall be submitted with the centralized E &P waste management facility permit, Form 28. The preliminary closure plan shall include, but not be limited to: A. A general plan for closure and reclamation of the entire facility, including a description of the activities required to decommission and remove all 900 -15 As of May 30, 2011 equipment, close and reclaim pits, dispose of or treat residual waste, collect samples as needed to verify compliance with soil and ground water standards, implement post - closure monitoring, and complete other remediation, as required. B. An estimate of the cost to close and reclaim the entire facility and to conduct post - closure monitoring. Cost estimates shall be subject to review by the Director. (2) Final closure plan. A detailed Site Investigation and Remediation Workplan, Form 27, shall be submitted at least sixty (60) days prior to closure for approval by the Director. The workplan shall include, but not be limited to, a description of the activities required to decommission and remove all equipment, close and reclaim pits, dispose of or treat residual waste, collect samples as needed to verify compliance with soil and ground water standards, implement post - closure monitoring, and complete other remediation, as required. h. Operators may be subject to local requirements for zoning and construction of facilities and shall provide copies of any approval notices, permits, or other similar types of notifications for the facility from local governments or other agencies to the Director for review prior to issuance of the operating permit. 909. SITE INVESTIGATION, REMEDIATION, AND CLOSURE a. Applicability. This section applies to the closure and remediation of pits other than drilling pits constructed pursuant to Rule 903.a.(3); investigation, reporting and remediation of spills /releases; permitted waste management facilities including treatment facilities; plugged and abandoned wellsites; sites impacted by E &P waste management practices; or other sites as designated by the Director. b. General site investigation and remediation requirements. (1) Sensitive Area Determination. Operators shall complete a sensitive area determination in accordance with Rule 901.e. (2) Sampling and analyses. Sampling and analysis of soil and ground water shall be conducted in accordance with Rule 910. to determine the horizontal and vertical extent of any contamination in excess of the concentrations in Table 910 -1. (3) Management of E &P waste. E &P waste shall be managed in accordance with Rule 907. (4) Pit evacuation. Prior to backfilling and site reclamation, E &P waste shall be treated or disposed in accordance with Rule 907. and the 1000 Series rules. (5) Remediation. Remediation shall be performed in a manner to mitigate, remove, or reduce contamination that exceeds the concentrations in Table 910 -1 in order to ensure protection of public health, safety, and welfare, and to prevent and mitigate significant adverse environmental impacts. Soil that does not meet concentrations in Table 910 -1 shall be remediated. Ground water that does not meet concentrations in Table 910 -1 shall be remediated in accordance with a Site Investigation and Remediation Workplan, Form 27. (6) Reclamation. Remediation sites shall be reclaimed in accordance with the 1000 Series rules for reclamation. 900 -16 As of May 30, 2011 c. Site Investigation And Remediation Workplan, Form 27. Operators shall prepare and submit for prior Director approval a Site Investigation and Remediation Workplan, Form 27, for the following operations and remediation activities: (1) Unlined pit closure when required by Rule 905. (2) Remediation of spills /releases in accordance with Rule 906. (3) Land treatment of oily waste in accordance with Rule 907.e.(2).F. (4) Closure of centralized E &P waste management facilities in accordance with Rule 908.g. Remediation of impacted ground water in accordance with Rule 910.b.(4). (5) d. Multiple sites. Remediation of multiple sites may be submitted on a single workplan with prior Director approval. e. Closure. (1) Remediation and reclamation shall be complete upon compliance with the concentrations in Table 910 -1, or upon compliance with an approved workplan. (2) Notification of completion. Within thirty (30) days after conclusion of site remediation and reclamation activities operators shall provide the following notification of completion: A. Operators conducting remediation operations in accordance with Rule 909.b. shall submit to the Director a Site Investigation and Remediation Workplan, Form 27, containing information sufficient to demonstrate compliance with these rules. B. Operators conducting remediation under an approved workplan shall submit to the Director, by adding or attaching to the original workplan, information sufficient to demonstrate compliance with the workplan. f. Release of financial assurance. Financial assurance required by Rule 706. may be held by the Director until the required remediation of soil and /or ground water impacts is completed in accordance with the approved workplan, or until cleanup goals are met. 910. CONCENTRATIONS AND SAMPLING FOR SOIL AND GROUND WATER a. Soil and groundwater concentrations. The concentrations for soil and ground water are in Table 910 -1. Ground water standards and analytical methods are derived from the ground water standards and classifications established by WQCC. b. Sampling and analysis. (1) Existing workplans. Sampling and analysis for sites subject to an approved workplan shall be conducted in accordance with the workplan and the sampling and analysis requirements described in this rule. (2) Methods for sampling and analysis. Sampling and analysis for site investigation or confirmation of successful remediation shall be conducted to determine the 900 -17 As of May 30, 2011 (3) nature and extent of impact and confirm compliance with appropriate concentration levels in Table 910 -1. A. Field analysis. Field measurements and field tests shall be conducted using appropriate equipment, calibrated and operated according to manufacturer specifications, by personnel trained and familiar with the equipment. B. Sample collection. Samples shall be collected, preserved, documented, and shipped using standard environmental sampling procedures in a manner to ensure accurate representation of site conditions. C. Laboratory analytical methods. Laboratories shall analyze samples using standard methods (such as EPA SW -846 or API RP -45) appropriate for detecting the target analyte. The method selected shall have detection limits less than or equal to the concentrations in Table 910 -1. D. Background sampling. Samples of comparable, nearby, non - impacted, native soil, ground water or other medium may be required by the Director for establishing background conditions. Soil sampling and analysis. A. Applicability. If soil contamination is suspected or known to exist as a result of spills /releases or E &P waste management, representative samples of soil shall be collected and analyzed in accordance with this rule. B. Sample collection. Samples shall be collected from areas most likely to have been impacted, and the horizontal and vertical extent of contamination shall be determined. The number and location of samples shall be appropriate to the impact. C. Sample analysis. Soil samples shall be analyzed for contaminants listed in Table 910 -1 as appropriate to assess the impact or confirm remediation. The analytical parameters shall be selected based on site - specific conditions and process knowledge and shall be agreed to and approved by the Director. D. Reporting. Soil Analysis Report, Form 24, shall be used when the Director requires results of soil analyses. E. Soil impacted by produced water. For impacts to soil due to produced water, samples from comparable, nearby non - impacted native soil shall be collected and analyzed for purposes of establishing background soil conditions including pH and electrical conductivity (EC). Where EC of the impacted soil exceeds the level in Table 910 -1, the sodium adsorption ratio (SAR) shall also be determined. F. Soil impacted by hydrocarbons. For impacts to soil due to hydrocarbons, samples shall be analyzed for TPH. 900 -18 As of May 30, 2011 (4) Ground water sampling and analysis. A. Applicability. Operators shall collect and analyze representative samples of ground water in accordance with these rules under the following circumstances: (i) Where ground water contamination is suspected or known to exceed the concentrations in Table 910 -1; (ii) Where impacted soils are in contact with ground water; or (iii) Where impacts to soils extend down to the high water table. B. Sample collection. Samples shall be collected from areas most likely to have been impacted, downgradient or in the middle of excavated areas. The number and location of samples shall be appropriate to determine the horizontal and vertical extent of the impact. If the concentrations in Table 910 -1 are exceeded, the direction of flow and a ground water gradient shall be established, unless the extent of the contamination and migration can otherwise be adequately determined. C. Sample analysis. Ground water samples shall be analyzed for benzene, toluene, ethylbenzene, xylene, and API RP -45 constituents, or other parameters appropriate for evaluating the impact. The analytical parameters shall be selected based on site - specific conditions and process knowledge and shall be agreed to and approved by the Director. D. Reporting. Water Analysis Report, Form 25, shall be used when the Director requires results of water analyses. E. Impacted ground water. Where ground water contaminants exceed the concentrations listed in Table 910 -1, operators shall notify the Director and submit to the Director for prior approval a Site Investigation and Remediation Workplan, Form 27, for the investigation, remediation, or monitoring of ground water to meet the required concentrations in Table 910 -1. 911. PIT, BURIED OR PARTIALLY BURIED PRODUCED WATER VESSEL, BLOWDOWN PIT, AND BASIC SEDIMENT /TANK BOTTOM PIT MANAGEMENT REQUIREMENTS PRIOR TO DECEMBER 30, 1997. a. Applicability. This rule applies to the management, operation, closure and remediation of drilling, production and special purpose pits, buried or partially buried produced water vessels, blowdown pits, and basic sediment /tank bottom pits put into service prior to December 30, 1997 and unlined skim pits put into service prior to July 1, 1995. For pits constructed after December 30, 1997 and skim pits constructed after July 1, 1995, operators shall comply with the requirements contained in Rules 901. through 910. b. Inventory. Operators were required to submit to the Director no later than December 31, 1995, an inventory identifying production pits, buried or partially buried produced water vessels, blowdown pits, and basic sediment /tank bottom pits that existed on June 30, 1995. The inventory required operators to provide the facility name, a description of the location, type, capacity and use of pit /vessel, whether netted or fenced, lined or unlined, and where available, water quality data. Operators who have failed to submit the required inventory are in continuing violation of this rule. 900 -19 As of May 30, 2011 c. Sensitive area determination. (1) For unlined production and special purpose pits constructed prior to July 1, 1995 and not closed by December 30, 1997, operators were required to determine whether the pit was located within a sensitive area in accordance with the Sensitive Area Determination Decision Tree, Figure 901 -1 (now Rule 901.e.) and submit data evaluated and analysis used in the determination to the Director on a Sundry Notice, Form 4. In December 2008, Figure 901 -1 was deleted from the 900 - Series Rules. (2) For steel, fiberglass, concrete, or other similar produced water vessels that were buried or partially buried and located in sensitive areas prior to December 30, 1997, operators were required to test such vessels for integrity, unless a monitoring or leak detection system was put in place. d. The following permitting /reporting requirements applied to pits constructed prior to December 30, 1997: (1) A Sundry Notice, Form 4, including the name, address, and phone number of the primary contact person operating the production pit for the operator, the facility name, a description of the location, type, capacity and use of pit, engineering design, installation features and water quality data, if available, was required for the following: A. Lined production pits and lined special purpose pits constructed after July 1, 1995. B. Unlined production pits constructed prior to July 1, 1995 which are lined in accordance with Rule 905. by December 30, 1997. (2) An Application For Permit For Unlined Pit, Form 15 was required for the following: A. Unlined production pits and special purpose pits in sensitive areas constructed prior to July 1, 1995, and not closed by December 30, 1997. B. Unlined production pits outside sensitive areas constructed after July 1, 1995 and not closed by December 30, 1997. (3) An Application For Permit For Unlined Pit, Form 15 and a variance under Rule 904.e.(1). (repealed, now Rule 502.b.) was required for unlined production pits and unlined special purpose pits in sensitive areas constructed after July 1, 1995. (4) A Sundry Notice, Form 4 was required for unlined production pits outside sensitive areas receiving produced water at an average daily rate of five (5) or less barrels per day calculated on a monthly basis for each month of operation constructed prior to December 30, 1997. e. The Director may have established points of compliance for unlined production pits and special purpose pits and for lined production pits in sensitive areas constructed after July 1, 1995. f. Closure requirements. (1) Operators of production or special purpose pits existing on July 1, 1995 which were closed before December 30, 1997, were required to submit a Sundry Notice, 900 -20 As of May 30, 2011 Form 4, within thirty (30) days of December 30, 1997. The Sundry Notice, Form 4 shall include a copy of the existing pit permit, if a permit was obtained, and a description of the closure process. (2) Pits closed prior to December 30, 1997 were required to be reclaimed in accordance with the 1000 Series rules. Pits closed after December 30, 1997 shall be closed in accordance with the 900 Series rules and reclaimed in accordance with the 1000 Series rules. (3) Operators of steel, fiberglass, concrete or other similar produced water vessels buried or partially buried and located in sensitive areas were required to repair or replace vessels and tanks found to be leaking. Operators shall repair or replace vessels and tanks found to be leaking. Operators shall submit to the Director a Sundry Notice, Form 4, describing the integrity testing results and action taken within thirty (30) days of December 30, 1997. (4) Closure of pits and steel, fiberglass, concrete or other similar produced water vessels, and associated remediation operations conducted prior to December 30, 1997 are not subject to Rules 905., 906., 907., 909. and 910. 912. VENTING OR FLARING NATURAL GAS a. The unnecessary or excessive venting or flaring of natural gas produced from a well is prohibited. b. Except for gas flared or vented during an upset condition, well maintenance, well stimulation flowback, purging operations, or a productivity test, gas from a well shall be flared or vented only after notice has been given and approval obtained from the Director on a Sundry Notice, Form 4, stating the estimated volume and content of the gas. The notice shall indicate whether the gas contains more than one (1) ppm of hydrogen sulfide. If necessary to protect the public health, safety or welfare, the Director may require the flaring of gas. c. Gas flared, vented or used on the lease shall be estimated based on a gas -oil ratio test or other equivalent test approved by the Director, and reported on Operator's Monthly Production Report, Form 7. d. Flared gas that is subject to Sundry Notice, Form 4, shall be directed to a controlled flare in accordance with Rule 903.b.(2) or other combustion device operated as efficiently as possible to provide maximum reduction of air contaminants where practicable and without endangering the safety of the well site personnel and the public. e. Operators shall notify the local emergency dispatch or the local governmental designee of any natural gas flaring. Notice shall be given prior to flaring when flaring can be reasonably anticipated, or as soon as possible, but in no event more than two (2) hours after the flaring occurs. Table 910 -1 CONCENTRATION LEVELS' Contaminant of Concern Concentrations Organic Compounds in Soil TPH (total volatile and extractable petroleum hydrocarbons) 500 mg /kg Benzene 0.17 mg /kg2 900 -21 As of May 30, 2011 Toluene 85 mg /kg2 Ethylbenzene 100 mg/kg2 Xylenes (total 175 mg/kg2 Acenaphthene 1,000 mg/kg2 Anthracene 1,000 mg/k92 Benzo(A)anthracene 0.22 mg /kg Benzo(B)fluoranthene 0.22 mg /k92 Benzo(K)fluoranthene 2.2 mg /kg Benzo(A)pyrene 0.022 mg/kg2 Chrysene 22 mg/kg2 Dibenzo(A,H)anthracene 0.022 mg/kg2 Fluoranthene 1,000 mg/kg2 Fluorene 1,000 mg/k92 Indeno(1,2,3,C,D)pyrene 0.22 mg /k q Napthalene 23 mg /kg Pyrene 1,000 mg/kg2 Organic Compounds in Ground Water Benzene 514/I3 Toluene 560 to 1,00014/13 Ethylbenzene 700 µg /I3 Xylenes (Total) 1,400 to 10,000 µg /I3'4 Inorganics in Soils Electrical Conductivity (EC) <4 mmhos /cm or 2x background Sodium Adsorption Ratio (SAR) <125 pH 6 -9 Inorganics in Ground Water Total Dissolved Solids (TDS) <1.25 x background3 Chlorides <1.25 x background3 Sulfates <1.25 x background3 Metals in Soils Arsenic 0.39 mg/kg2 Barium (LDNR True Total Barium) 15,000 mg /kg2 Boron (Hot Water Soluble) 2 mg /13 Cadmium 70 mg /kg3'6 Chromium (III) 120,000 mg/kg2 Chromium (VI) 23 mg /kg2'6 Copper 3,100 mg/kg2 Lead (inorganic) 400 mg/kg2 Mercury 23 mg/kg2 Nickel (soluble salts) 1,600 mg /kg2'6 Selenium 390 mg /kg2•6 Silver 390 mg/kg2 Zinc 23,000 mg /kg2'6 Liquid Hydrocarbons in Soils and Ground Water Liquid hydrocarbons including condensate and oil Below detection level COGCC recommends that the latest version of EPA SW 846 analytical methods be used where possible and that analyses of samples be performed by laboratories that maintain state or national accreditation programs. 1 Consideration shall be given to background levels in native soils and ground water. 2 Concentrations taken from CDPHE -HMWMD Table 1 Colorado Soil Evaluation Values (December 2007). 3 Concentrations taken from CDPHE -WQCC Regulation 41 - The Basic Standards for Ground Water. 4 For this range of standards, the first number in the range is a strictly health -based value, based on the WQCC's established methodology for human health -based standards. The second number in the range is a maximum contaminant level (MCL), established under the Federal Safe Drinking Water Act which has been 900 -22 As of May 30, 2011 determined to be an acceptable level of this chemical in public water supplies, taking treatability and laboratory detection limits into account. The WQCC intends that control requirements for this chemical be implemented to attain a level of ambient water quality that is at least equal to the first number in the range except as follows: 1) where ground water quality exceeds the first number in the range due to a release of contaminants that occurred prior to September 14, 2004 (regardless of the date of discovery or subsequent migration of such contaminants) clean -up levels for the entire contaminant plume shall be no more restrictive than the second number in the range or the ground water quality resulting from such release, whichever is more protective, and 2) whenever the WQCC has adopted alternative, site - specific standards for the chemical, the site - specific standards shall apply instead of these statewide standards. 5 Analysis by USDA Agricultural Handbook 60 method (20B) with soluble cations determined by method (2). Method (20B) = estimation of exchangeable sodium percentage and exchangeable potassium percentage from soluble cations. Method (2) = saturated paste method (note: each analysis requires a unique sample of at least 500 grams). If soils are saturated, USDA Agricultural Handbook 60 with soluble cations determined by method (3A) saturation extraction method. 6 The table value for these inorganic constituents is taken from the CDPHE -HMWMD Table 1 Colorado Soil Evaluation Values (December 2007). However, because these values are high, it is possible that site - specific geochemical conditions may exist that could allow these constituents to migrate into ground water at levels exceeding ground water standards even though the concentrations are below the table values. Therefore, when these constituents are present as contaminants, a secondary evaluation of their leachability must be performed to ensure ground water protection. 900 -23 As of May 30, 2011 OPERATION AND MAINTENANCE COMPLIANCE PLAN Piceance Centralized Soil Treatment Facility Garfield County, Colorado APPENDIX C Prepared by: PDC Energy, Inc. Denver, Colorado Reserved - COGCC Performance Bond TO BE INSERTED UPON APPROVAL AND RECEIPT Reserved - COGCC FACILITY OPERATION PERMIT TO BE INSERTED UPON APPROVAL AND RECEIPT AIR POLLUTION CONTROL DIVISION CONSTRUCTION PERMIT GARFIELD COUNTY MAJOR IMPACT REVIEW PERMIT AND APPLICATION DOCUMENTS FINAL PERMIT APPROVAL TO BE INSERTED UPON APPROVAL AND RECEIPT OPERATION AND MAINTENANCE COMPLIANCE PLAN Piceance Centralized Soil Treatment Facility Garfield County, Colorado APPENDIX D Prepared by: PDC Energy, Inc. Denver, Colorado 'ISM Designation: D 6009 — 96 (Reapproved 2001) Standard Guide for Sampling Waste Piles1 This standard is issued under the fixed designation D 6009; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon (e) indicates an editorial change since the last revision or reapproval. 1. Scope 1.1 This guide provides guidance for obtaining representa- tive samples from waste piles. Guidance is provided for site evaluation, sampling design, selection of equipment, and data interpretation. 1.2 Waste piles include areas used primarily for waste storage or disposal, including above —grade dry land disposal units. This guide can be applied to sampling municipal waste piles. 1.3 This guide addresses how the choice of sampling design and sampling methods depends on specific features of the pile. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appro- priate safety and health practices and determine the applica- bility of regulatory limitations prior to use. 2. Referenced Documents 2.1 ASTM Standards: D 1452 Practice for Soil Investigation and Sampling by Auger Borings2 D 1586 Test Method for Penetration Test and Split — Barrel Sampling of Soils2 D 1587 Practice for Thin — Walled Tube Geotechnical Sam- pling of Soils2 D 4547 Practice for Sampling Waste and Soils for Volatile Organics' D 4687 Guide for General Planning of Waste Sampling' D 4700 Guide for Soil Sampling from the Vadose Zone2 D 4823 Guide for Core — Sampling Submerged, Unconsoli- dated Sediments' D 5088 Practice for Decontamination of Field Equipment Used at Nonradioactive Sites' D 5314 Guide for Soil Gas Monitoring in the Vadose Zone' D 5451 Practice for Sampling Using a Trier Sampler' D 5518 Guide for Acquisition of File Aerial Photography and Imagery for Establishing Historic Site —Use and Surfi- cial Conditions' This guide is under the jurisdiction of ASTM Committee D34 on Waste Management and is the direct responsibility of Subcommittee D34.01.01 on Planning for Sampling. Current edition approved Oct. 10, 1996. Published December 1996. Z Annual Book of ASTM Standards, Vol 04.08. 3 Annual Book of ASTM Standards, Vol 11.04. 4 Annual Book of ASTM Standards, Vol 11.02. 5 Annual Book of ASTM Standards, Vol 04.09. D 5730 Guide to Site Characterization for Environmental Purposes with Emphasis on Soil, Rock, the Vadose Zone and Ground Waters 3. Terminology 3.1 Definitions of Terms Specific to This Standard: 3.1.1 hot spots— strata that contain high concentrations of the characteristic of interest and are relatively small in size when compared with the total size of the materials being sampled. 3.1.2 representative sample —a sample collected such that it reflects one or more characteristics of interest (as defined by the project objectives) of the population from which it was collected. 3.1.2.1 Discussion —A representative sample can be a single sample, a set of samples, or one or more composite samples. 3.1.3 waste pile — unconfined storage of solid materials in an area of distinct boundaries, above grade and usually uncovered. This includes the following: 3.1.3.1 chemical manufacturing waste pile —a pile consist- ing primarily of discarded chemical products (whether market- able or not), by— products, radioactive wastes, or used or unused feedstocks. 3.1.3.2 scrap metal or junk pile —a pile consisting primarily of scrap metal or discarded durable goods such as appliances, automobiles, auto parts, or batteries. 3.1.3.3 trash pile —a pile of waste materials from municipal sources, consisting primarily of paper, garbage, or discarded nondurable goods that contain or have contained hazardous substances. It does not include waste destined for recyclers. 4. Significance and Use 4.1 This guide is intended to provide guidance for sampling waste piles. It can be used to obtain samples for waste characterization related to use, treatment, or disposal; to monitor an active pile; to prepare for closure of the waste pile; or to investigate the contents of an abandoned pile. 4.2 Techniques used to sample include both in —place evalu- ations of the pile and physically removing a sample. In —place evaluations include techniques such as remote sensing, on —site gas analysis, and permeability. 4.3 Sampling strategy for waste piles is dependent on the following: 4.3.1 Project objectives including acceptable levels of error when making decisions; Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428 -2959, United States. 1 �STM D 6009 4.3.2 Physical characteristics of the pile, such as its size and configuration, access to all parts of it, and the stability of the pile; 4.3.3 Process that generated the waste and the waste char- acteristics, such as hazardous chemical or physical properties, whether the waste consists of sludges, dry powders or granules, and the heterogeneity of the wastes; 4.3.4 History of the pile, including dates of generation, methods of handling and transport, and current management methods; 4.3.5 Regulatory considerations, such as regulatory classi- fication and characterization data; 4.3.6 Limits and bias of sampling methods, including bias that may be introduced by waste heterogeneity, sampling design, and sampling equipment. 4.4 It is recommended that this guide be used in conjunction with Guide D 4687, which addresses sampling design, quality assurance, general sampling considerations, preservation and containerization, cleaning equipment, packaging, and chain of custody. 4.5 A case history of the investigation of a waste pile is included in Appendix X1. 5. Site Evaluation 5.1 Site evaluations are performed to assist in designing the most appropriate sampling strategy. An evaluation may consist of on —site surveys and inspections, as well as a review of historical data. Nonintrusive geophysical and remote sensing methods are particularly useful at this stage of the investigation (see Guide D 5518). Table 1 summarizes the effects that various factors associated with the waste pile, such as the history of how the pile was generated, have upon the strategy and design of the sampling plan. The strategic and design considerations are discussed as well. 5.2 Generation History The waste pile may have been created over an extended time period. A remote sensing method that is very useful in establishing historical management practices for waste piles is aerial imagery. Aerial photographs are widely available and may be used to determine the history of a waste pile, sources of waste, and the presence and distribution of different strata. Satellite imagery could be used for larger waste piles. TABLE 1 Strategy Factors Waste Pile Factors Strategic Considerations Design Considerations Generation history Physical characteristics of pile: — size — shape — stability Waste characteristics Date of generation Types of processes Characteristics by process Delivery method Current management Regulatory considerations Physical variability of pile Access Safety Constituents present Constituent distribution Heterogeneity — physical variability — chemical variability Analysis required Location of samples Number of samples Location of samples Equipment selection Number of samples Analysis required Location of samples Representative samples Equipment selection 2 5.2.1 The date of generation could be important with respect to the types of processes that generated the waste, the charac- teristics of the waste, the distribution of the constituents, and regulatory concerns. 5.2.2 The type of process that generated the waste will determine the types of constituents that may be present in the waste pile. Chemical variability will influence the number of samples that are required to characterize the waste pile unless a directed (biased) sampling approach is acceptable. 5.2.3 The delivery method of the material to the waste pile could influence the concentrations of the constituents, affect the overall shape of the pile, or create physical dissimilarity within the waste pile through sorting by particle size or density. 5.2.4 If the pile is under current management and use, the variability in constituent types and concentrations may be affected. Current management activities also may influence the regulatory status of the waste pile. 5.2.5 Regulatory considerations will typically focus on waste identification questions, in other words is the material a solid waste that should be regulated and managed as a hazardous waste (1).6 This may involve a limited, directed sampling approach, particularly if a regulatory agency is conducting the investigation. A more comprehensive sampling design may be required to determine if the waste classifies as hazardous. Remediation efforts and questions regarding per- mits may focus on characterizing the entire pile, possibly as the removal of material is occurring. It should be noted that concentrations of contaminants near regulatory levels may increase the number of samples required to meet the objectives of the investigation. These regulatory levels could be those established to determine if a waste is hazardous, or "cleanup" levels set for a removal or remediation. 5.3 Physical Characteristics of Pile— Several physical characteristics of the waste pile must be considered during the site evaluation. Variability in size, shape, and stability of the pile affects access to it to obtain samples as well as safety considerations. Physical variability will influence the number of samples that are required to characterize the waste pile unless a directed (biased) sampling approach is considered to be acceptable. Techniques that might be used include resistivity and seismic refraction (for determining the depth of very large piles). 5.3.1 The size of the waste pile will influence the sampling strategy in that increasing size is often accompanied by increased variability in the physical characteristics of the waste pile. The number of samples, however, that are needed to characterize a waste pile adequately will typically be a function of the study objectives as well as the inherent variability of the pile. 5.3.2 The shape of the waste pile can influence the sampling strategy by limiting access to certain locations within the pile, and if it is topologically complex it is difficult to lay out a sampling grid. Also, a waste pile may extend vertically both above and below grade, making decisions regarding the depth of sample collection difficult. 6 The boldface numbers in parentheses refer to the list of references at the end of this standard. 100) D 6009 5.3.3 The stability of the waste pile also can limit access to both the face and the interior of the pile. The use of certain types of heavier sampling equipment also could be limited by the ability of the pile to bear the weight of the equipment. 5.4 Waste Characteristics: 5.4.1 The constituents could include inorganics, volatile organic compounds (VOCs), and semivolatile organic com- pounds (including pesticides and polychlorinated biphenyls (PCBs)) (see Practice D 4547). Speciality analyses may be warranted, such as leaching tests or analyses for dioxin/furans or explosive compounds. Soil gas sampling is a minimally intrusive technique that may detect the presence and distribu- tion of volatile organic compounds in soils and in porous, unconsolidated materials. Appropriate applications for soil gas monitoring are identified in Guide D 5314. 5.4.2 The distribution of constituents in the waste pile could be influenced by changes in the manufacturing process which resulted in changes in the composition of the waste; the length of time the material has remained in the pile (particularly for VOCs); the mode of delivery of the waste materials to the pile; and management practices, such as mixing together wastes from more than one process. 5.4.3 Physical and chemical variabilities would include variability in the chemical characteristics of the material within the pile, as well as variability in particle size, density, hardness, whether brittle or flexible, moisture content, consolidated, or unconsolidated. The variability may be random or found as strata of materials having different properties or containing different types or concentrations of constituents. 5.4.3.1 Geophysical survey methods may be used on piles to estimate physical homogeneity, which may or may not be related to chemical homogeneity, and to detect buried objects, both of which may need to be considered during the develop- ment of the sampling design and the safety plan for the investigation. The most suitable technique for detecting non- metallic objects is electromagnetics. Ground — penetrating radar, a more sophisticated and complex technique, also may be considered. Electromagnetic techniques are suited particularly to large piles that contain leachate plumes (for example, mine tailings) or for the detection of large discontinuities in a pile (for example, different types of wastes or the transition from a disposal area to background soils). For metallic objects, metal detectors and magnetometers are useful and relatively easy to use in the field. 5.5 Potential Investigation Errors: 5.5.1 Equipment selection can bias sampling results even if the equipment is used properly. Bias can result from the incompatibility of the materials that the sampling equipment is made of with the materials being sampled. For example, the equipment could alter the characteristics of the sample. Some equipment will bias against the collection of certain particles sizes, and some equipment cannot penetrate the waste pile adequately. 5.5.2 Equipment, use, and operation can introduce error (bias) into the characterization of a waste pile. Sampling errors typically are caused when certain particle sizes are excluded, when a segment of the waste pile is not sampled, or when a location outside the pile is inadvertently sampled. 3 5.5.3 When stratification, layering, or solid phasing occurs it may be necessary to obtain and analyze samples of each of the distinct phases separately to minimize sampling bias. Care should be taken when sampling stratified layers to minimize cross contamination. Proper decontamination procedures should be used for all sampling equipment (see Practice D 5088). 5.5.4 Statistical bias includes situations where the data are not normally distributed or when the sampling strategy does not allow the potential for every portion of the pile to be sampled. 6. Sampling Strategy 6.1 Developing a strategy for sampling a waste pile requires a thorough examination of the site evaluation factors listed in Section 5. The location and frequency of sampling (number of samples) should be outlined clearly in the sampling plan, as well as provisions for the use of special sampling equipment, access of heavy equipment to all areas of the pile, if necessary, and so forth. 6.1.1 Representative Sampling —The collection of a repre- sentative set of samples from a waste pile typically will be complicated by the presence of a number of the site evaluation factors (2,3). 6.1.2 Heterogeneous Wastes —Waste piles may be homoge- neous, for applied purposes, or may be quite heterogeneous in particle size and contaminant distribution. If the particle sizes of the material in the waste pile and the distribution of contaminants are known, or can be estimated, then less sampling may be necessary to define the properties of interest in the waste pile. An estimate of the variability in contaminant distribution may be based on process knowledge or determined by preliminary sampling (4). The more heterogeneous the waste pile is, the greater the planning and sampling require- ments. 6.1.3 Strata and Hot Spots —A waste pile also could contain strata that have less internal variation in physical properties or concentrations of chemical constituents than the remainder of the waste pile (2,5). For example, strata may be present in a waste pile due to changes in the process that generated the waste, or if different processes at a facility contribute waste to different parts of the waste pile. A stratified sampling strategy would consider this situation by conducting independent sam- pling of each stratum, which could reduce the number of samples required. These strata could be in specific areas of the waste pile (4). Also, hot spots may be present in the waste pile that are unique in composition (2,5). 6.2 Specific Sampling Strategies: 6.2.1 Although the most appropriate method for evaluating material in waste piles is to sample at or immediately following the point of generation (for example, conveyor belt), most sampling problems involve existing or in —place waste piles. Therefore, the following discussion will focus on in —place waste piles. Sampling strategies available for waste piles include directed or judgmental sampling, simple random sam- pling, stratified random sampling, systematic grid sampling, and systematic sampling over time (2,6). General concerns about the collection of a representative sample, the existence of potential heterogeneity in the waste pile, the presence of strata In" D 6009 within the waste pile, and the existence of distinct hot spots within the waste pile may also influence the selection of an appropriate sampling strategy and development of the sam- pling plan (5). The following paragraphs provide an introduc- tion to determining the appropriate number of samples to collect and the sampling strategies available for determining sample locations. 6.2.2 Determining the Frequency or Number of Samples — The frequency of sampling or the number of samples to collect typically will be based on several factors including the study objectives, properties of wastes in the pile, degree of confi- dence required, access to sampling points, and budgetary constraints. Practical guidance for determining the number of samples is included in Guide D 4687 and Refs (2, 3). 6.2.3 Directed Sampling — Directed sampling (Fig. 1) is based on the judgment of the investigator and will not result necessarily in a sample that reflects the characteristics of the entire waste pile. Directed sampling also is called judgmental sampling, authoritative sampling, or nonprobability sampling. The experience of the investigator often is the basis for sample collection, and, depending on the study objectives, bias should be recognized as a potential problem. For preliminary screen- ing investigations of a waste pile and for certain regulatory investigations, however, directed sampling may be appropriate. A A OBLIQUE VIEW PLAN VIEW SIDE VIEW FIG. 1 Waste Pile Sampling Strategy— Directed Sampling A A directed sampling strategy could call for the collection of a composite sample from the surface area or the collection of discrete grabs at the surface of the pile (see Fig. 1). Directed sampling would typically focus on worst case conditions in a waste pile, for example, the most visually contaminated area or most recently generated waste. 6.2.4 Simple Random Sampling — Simple random sampling (Fig. 2) ensures that each element in the waste pile has an equal chance of being included in the sample (2). This may be the method of choice when, for purposes of the investigation, the waste pile is randomly heterogeneous (5). If the waste pile contains trends or patterns of contamination, a stratified ran- dom sampling or systematic grid sampling strategy would be more appropriate (2) (see 6.2.5 and 6.2.6). 6.2.4.1 A simple random approach could use a grid with random grids selected for sample collection (see Fig. 2). Note that the grid size could be selected based on the number of samples that are required (some guidance suggests having at least ten times the number of grids as samples required). Once the grid is overlaid and the sampling locations are selected, the decision must be made to collect either a discrete grab sample (surface), a composite of surface samples taken from predes- ignated locations within the grid cell (based on compass points), a vertical composite to a specified depth, or discrete A OBLIQUE VIEW PLAN VIEW A A A / \ A 4 SIDE VIEW FIG. 2 Waste Pile Sampling Strategy — Simple Random Sampling In" D 6009 grab samples at specified depths. If discrete grab samples are desired at specified depths, they typically would be collected at the same location as the bore hole is advanced into the pile. Fig. 2 illustrates the collection of vertical composites at each of the randomly selected locations. 6.2.5 Stratified Random Sampling — Stratified random sam- pling (see Fig. 3) may be useful when distinct strata or homogeneous subgroups are identified within the waste pile (2). The strata may be located in different areas of the pile or may be comprised of different layers (see Fig. 3). This approach is useful when the individual strata may be consid- ered internally homogeneous or at least have less internal variation in what would otherwise be considered a heteroge- neous waste pile (2). Information on the waste pile usually is required to establish the location of individual strata unless process knowledge or changes in the composition of the material is obvious, such as with discoloration or with the type of waste. The grid may be utilized for sampling several horizontal layers if the strata are oriented horizontally (4). A simple random sampling approach then is used within each stratum. The use of a stratified random sampling strategy may result in the collection of fewer samples. Fig. 3 illustrates a scenario where the number of samples collected in each stratum varies (plan view), and discrete grabs are collected in A A OBLIQUE VIEW PLAN VIEW • • SIDE VIEW FIG. 3 Waste Pile Sampling Strategy— Stratified Random Sampling A A 5 each boring at predesignated depths (side view). 6.2.6 Systemic Grid Sampling — Systematic grid sampling (see Fig. 4) involves the collection of samples at fixed intervals and is useful when the contamination is assumed to be distributed randomly (2). This method also is commonly used with waste piles when estimating trends or patterns of con- tamination or when the objective is to locate hot spots. This approach may not be acceptable if the entire waste pile is not accessible or if the sampling grid locations become phased with variations in the distribution of contaminants within the waste pile (6). It also may be useful for identifying the presence of strata within the pile. The grid and starting points should be laid out randomly over the waste pile, yet the method allows for rather easy location of exact sample locations by means of the grid (see Fig. 4). The same considerations discussed in 6.2.4 concerning the depth of each sample (surface, vertical composite, discrete grabs at depth) also should be considered. Fig. 4 illustrates the collection of vertical composites at each grid, which could be difficult and costly. Also note that the grid size typically would be adjusted according to the number of samples that are required. 6.2.7 Systematic Sampling Over Time— Systematic sam- pling over time at the point of generation is useful if the material is being sampled from a conveyor belt or being A A OBLIQUE VIEW PLAN VIEW A A SIDE VIEW FIG. 4 Waste Pile Sampling Strategy— Systematic Grid Sampling 10111 D 6009 delivered by means of truck or pipeline to the waste pile. The sampling interval can be determined on a time basis, for example, every hour from a conveyor belt or pipeline dis- charge, or from every third truck load. The time between intervals is influenced by the factors addressed in 6.2.2. 6.2.8 Alternative Approach —In many cases, an objective of waste pile characterization is to determine the impact of the pile on the environment. At times this may be accomplished more easily by sampling the routes by which contaminants are dispersed from the pile than through direct sampling of the pile, especially for piles that are difficult to characterize. For example, ground water up— and —down gradient from the pile could be sampled to check for ground water contamination. The vadose zone below the pile also might be sampled to detect leachate (and potential ground water contamination) through soil sampling, vacuum lysimeters, or soil gas. Surface water and sediment in drainage channels down gradient from the pile also might be sampled. Surface soils, air samples, and con- taminants deposited on vegetation can be used as indicators of atmospheric transport of contaminants from the pile, including both particulate and volatile materials. Such approaches will seldom replace pile sampling completely, but they may reduce the number of pile samples needed to make remedial action decisions (see Guide D 5730), also Refs (7 -9). 7. Selection of Sampling Equipment 7.1 Wastes in piles are often complex, multiphase mixtures of solids and semisolids. The wastes can range from powders to granules to large, heterogeneous solid fragments and can cover many acres in area. No single type of sampler can be used to collect representative samples of all types of waste from piles. Large, thick piles may require drill rigs to obtain samples from depth. The sampling of gases from within the pile requires other types of equipment. Table 2 lists typical waste types and the corresponding recommended samplers to use. 7.2 Sampling at depth from inside the pile may require heavy equipment designed for excavation or removal of soil or rock. Table 3 lists such equipment and its applications for sampling waste piles (10). 7.3 Sampling equipment should be constructed of materials that are compatible with the waste to be sampled. Compatibil- ity refers to the physical durability, lack of chemical reactivity with the waste, and lack of potential for contamination of the waste with analytes of concern. Typical materials of construc- tion include stainless steel, plastic, and glass. 8. Data Use 8.1 The decisions that will be made based upon the data must be identified early in the planning process since these affect the approach to the problem and how the data will be evaluated. Decisions affecting waste classification, closure, and post — closure issues, are examples of the uses of the data. Methods to determine the volume of contaminated material in a pile or pile strata may be needed. Standard mathematical formulas for calculating the volume of a cone, cylinder, various prisms, and so forth, may be used. 8.2 Statistical Considerations: 8.2.1 Data quality assessment (DQA) methods are used to evaluate the data for any anomalies and to evaluate the assumptions for statistical evaluation. The statistician makes use of both subjective judgment (graphical analysis for iden- tification of trends and anomalies) and statistical models and inference (for example, outlier detection, autocorrelation esti- mation) in the investigation of data for validity of the assump- tions needed to make a statistical test. Classical statistical models assume that the samples collected from the population of interest are independent and have an identical probability distribution (that is, normal distribution with constant mean and variance). Random sampling is a method to ensure independence. The probability distributional assumptions are part of DQA that will determine if the classical statistical TABLE 2 Sampling Devices Suitable for Waste Piles" Location and Waste Type Sampling Devices ASTM Standard Limitations Subsurface Powdered, granular, or soil -like solids; sludges split - barrel push coring device trier auger thin - walled tube sampler drill rigs soil gas samplers Surface Powdered, granular, or soil -like solids; sludges trowel or scoop Slag hammer /chisel Impact device D 1586 D 1587 D 4700 D 4823 D 5451 D 1452 D 4700 D 4823 D 4700 Limited application for sampling moist and sticky solids, or particles with diameter 0.6 cm (0.25 in.) or more. Depth limitation of about 1 m. May not retain core sample of very dry granular materials. Not applicable to sampling solid wastes with particle diameter >1 the diameter of the sampling tube. Does not collect undisturbed sample. Collects relatively undisturbed core. Difficult to use on gravelly or rocky soils. Used for geoenvironmental exploration. To minimize sample contamination, avoid those using a water -based drilling fluid. D 5314 Used for volatile organic compounds. D 4700 Not applicable to sampling deeper than 8 cm (3 in.). Difficult to obtain reproducible mass of sample. May exclude certain particle sizes, especially large aggregates. Changes particle size. A This table is not all inclusive; other equipment may be used. 6 �S1M D 6009 TABLE 3 Excavation and Removal Equipment for Waste Piles Excavation and Removal General Ability to Excavate Hard Equipment Excavation and Compacted Material Soil Hauling Mixing of Solids, Soil Spreading Cover Site Maneuverability Wheel or crawler Mounted backhoe Wheel or crawler Mounted front —end loader Skid steer loader Bulldozer A" A A A A A B A BB /Oc A/B B 0 A A A O A A B A NB NB A B A A = Good choice. Equipment is fully capable of performing function listed. B B = Secondary choice. Equipment is marginally capable of performing function listed. O = Not applicable or poor choice. model is appropriate for the collected data. For directed sampling, the sampling is subjective and the sample results are typically judged on a qualitative basis. 8.2.2 Simple random sampling will provide an unbiased estimate of the average waste concentration, that is, an estimate of the mean. This unbiased estimate is independent of the geometry of the pile and of the distribution of the concentration of the contaminants, but it may not have the smallest variance. Other sampling designs, such as systematic grid sampling or stratified random sampling, may provide an average that has a smaller variance. If the waste pile has uneven topography, the calculation of the mean concentration of the pile should be a volume— weighted average, using core volume as the weighting factor to reduce the variance of the estimated mean. 8.2.2.1 For simple random sampling and systematic grid sampling designs, histogram and normal probability plots of the sample data can be used to judge if the data conform to normal distribution. If not, there are several alternatives. First, the classical statistical model may still be considered robust for the decision — making process. Second, a transformation of the data may approximate a normal distribution of the data. For example, logarithmic transformation will normalize data that are lognormal originally. If the data are lognormal, the question of whether to use the arithmetic mean or the geometric mean for decision — making purposes must be decided. Third, an alternative statistical model based on nonparametric methods, but which uses weaker assumptions, may be proposed to analyze the decision — making process. It may be advisable to consult a statistician. 8.2.2.2 For the stratified random sampling design, the test of normality is not straightforward. Generally, it requires a mathematical model to take out the strata effects first, then test for normality using the residuals. A statistician should be consulted. 8.2.2.3 In any of these cases, alternative consequences of the level of uncertainty can be calculated prior to collecting the data. These alternatives can be used by decision — makers to select the best strategy to minimize the environmental risks. 9. Keywords 9.1 piles; sampling; waste APPENDIX (Nonmandatory Information) Xl. WASTE PILE —A CASE HISTORY X1.1 Background —The waste pile was generated by a facility that produces brass alloys from scrap metal. The byproduct from this operation was slag, which was generated in the recovery furnace. The slag was ground subsequently in a ball mill prior to being reintroduced into the recovery furnace. A large amount of the ground slag was disposed of in a waste pile which covered about one acre. No active manage- ment was occurring with the waste pile. No buried containers or extremely heterogenous material (unground slag) was sus- pected of being present in the waste pile based on facility records and interviews of personnel. X1.1.1 Lead and cadmium were the constituents of concern based on process knowledge, and the possibility for the waste being hazardous was the regulatory consideration. The poten- tial for off —site migration of contaminants was also an imme- diate concern, and this was considered in the development of the Phase 1 study design. Fig. X1.1 shows a site map of the 7 facility and the slag pile. Fig. X1.2 shows a computer enhance- ment of the slag pile, and Fig. X1.3 shows a topographic view of the pile. X1.2 Phase 1: X1.2.1 Objective —The primary objective of the initial in- vestigation was to determine if the slag in the waste pile classified as hazardous based on the concentration of lead and cadmium in a leach test. A secondary objective was to provide preliminary information on the potential migration and trans- port of contaminants from the waste pile off -site. The sampling plan for this initial investigation utilized a directed sampling strategy to provide a preliminary estimate of the lead concen- tration in the waste, the variability of contaminant concentra- tions in the pile, and the potential for leaching using the applicable leaching procedure mandated in regulations. Four composite samples were collected from the surface (0 to 15 cm or 0 to 6 in.) of the waste pile at locations within the four �S1M D 6009 GpP r SOIL DIKE SLAG PILE 'FIREBRICK PILE FIG. X1.1 Site Map BALL MILL RESIDUE PILE APPROXIMATE SCALE 300 0 300 (IN FEET) 1 INCH = 300 FT quadrants. The following environmental samples were also X1.2.1.2 Sediment upstream and downstream in a stream collected: which borders the facility, X1.2.1.1 Several soil samples in the vicinity of the waste X1.2.1.3 Sediment in a ditch which contained runoff from pile, the pile, and 8 11(0i 1p0. 300' In" D 6009 FIG. X1.2 Computer Enhancement of the Slag Pile (Front View) Scale 1:1:2 300, �•�A�� 0' 0' FIG. X1.3 Topographic View of the Slag Pile X1.2.1.4 Two background soil samples. X1.2.2 Fig. X1.4 shows the Phase 1 sampling locations within the slag pile, and Fig. X1.5 shows the same sampling locations on the topographic map of the pile. X1.2.3 Results —Zinc, copper, cadmium, and lead were all elevated (compared to background) in the samples collected from the waste pile, and the concentrations did not appear to vary significantly between the samples. Since lead and cad- mium are regulated constituents, a leach test was completed, and the lead results exceeded the regulatory level of 5 mg /L. Cadmium was just under the regulatory level of 1.0 mg/L. Lead and cadmium concentrations in the soil were 2 to 3 times above background, and the drainage ditch and downstream sediment sample also had elevated lead and cadmium levels. X1.2.4 Conclusion— The waste pile contained slag that is hazardous for lead. The waste pile required further character- ization to determine the variability in the pile. The presence of 9 300' 300' lead and cadmium in soils and the stream sediment down- stream of the facility was confirmed and should be investigated further to determine the extent of contaminant transport. X1.3 Phase 2: X1.3.1 Objective —The objective is to characterize the waste pile further using a systematic grid sampling design. This design will delineate horizontal and vertical variability in lead and cadmium concentrations. The Phase 1 investigation also provided a good estimate of the anticipated variability in the waste pile. The number of samples required to characterize the waste pile adequately was calculated based on the average concentration, the anticipated variability, the regulatory level of concern, and the specified confidence interval. The grid size then was adjusted to accommodate the projection on the required number of samples. Composite samples were col- lected within each grid cell based on one center point and eight 300' In" D 6009 0' ..,...0, FIG. X1.4 Front View of the Slag Pile Showing Sampling Locations Scale 1:1:2 -- rooms- 0' a' FIG. X1.5 Topographic View of the Slag Pile Showing Sampling Locations points on the compass (45° intervals) equidistant from the center point. Ten percent of the grids were designated for vertical as well as surface (0 to 15 cm or 0 to 6 in.) sample collection. Additionally, 10 % of the grids were designated randomly for duplicate sampling (using a different aliquot pattern) to check the preliminary estimate on the variability. Additional environmental sampling was conducted but will not be covered in this discussion. X1.3.2 Results —The results supported the initial Phase 1 investigation with lead consistently exceeding the regulatory level. Cadmium consistently was below the regulatory level. X1.3.3 Conclusion— The waste pile was characteristic for lead and classified as hazardous according to the applicable regulations. There was no significant variability with depth, although several gradients were noticed across the grid based on lead concentration (scan) results. 10 X1.4 Phase 3: 300' 300' X1.4.1 Objective —The objective is to determine thevolume of the waste pile in order to estimate both the disposal cost and the total amount of the civil penalty to be charged to the owner of the pile. The waste pile was surveyed using standard surveying techniques. X1.4.2 Results —The results were used to calculate the volume using geometric principles. Also, a computer program was utilized which constructs contours based on the surveying information. The computer program was used as a check of the manual method, which produced a result that was 10 % higher in volume than the computer program. X1.4.3 Conclusion— For penalty calculation purposes, the smaller estimate was utilized; however, the actual treatment and disposal costs could reflect the larger estimate. In" D 6009 REFERENCES (1) U.S. Environmental Protection Agency (EPA). 1986. Test Methods for Evaluating Solid Waste; SW -846, 3rd Edition. EPA/530 /SW -846 (NTIS PB88- 239223); First update, 3rd edition. EPA/530/SW- 846.3 -1 (NTIS PB89- 148076). Current edition and updates available on a subscription basis from U.S. Government Printing Office, Stock #955- 001- 00000 -1. (2) Gilbert, R. 0., "Statistical Methods for Environmental Pollution Monitoring," Van Nostrand Reinhold Co., 1987. (3) Ford, P. J., and Turina, P. J., Characterization of Hazardous Waste Sites —A Methods Manual, Vol 1: Site Investigations, EPA 600/4 -84/ 075, (NTIS PB85- 215960), 1985. (4) U.S. Environmental Protection Agency (EPA), Compendium of ERT Waste Sampling Procedures, Section 5.0 Waste Pile Sampling, SOP No. 2017, EPA 540/P- 91/008, OSWER Directive 9360.4 -07, January 1991. (5) Pitard, F., Pierre Gy's Sampling Theory and Sampling Practice, Vol 1: Heterogeneity and Sampling, Chemical and Rubber Company (CRC) Press, 1989. (6) U.S. Environmental Protection Agency (EPA), Characterizing Hetero- geneous Wastes: Methods and Recommendations, EPA 600/R- 92/033, (NTIS PB92- 216894) February 1992. {Also published as hardback Smoley Edition: Rupp and Joens (1993).] (7) Keith, L., Principles of Environmental Sampling, Ed. ACS, 1988. (8) U.S. Environmental Protection Agency (EPA). Guidance Document on the Statistical Analysis of Ground Water Monitoring Data at RCRA Facilities, Office of Solid Waste, 1993. (9) McCoy and Associates, Inc., "Soil Sampling and Analysis— Practices and Pitfalls," Hazardous Waste Consultant, Vol 10, No. 6, Lakewood, CO, 1992. (10) PEI Associates, 1991, Survey of Materials - Handling Technologies Used at Hazardous Waste Sites, EPA 540/2- 91/010, June 1991. (NTIS PB91- 186924), 225 pp. The American Society for Testing and Materials takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility. This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years and if not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standards and should be addressed to ASTM Headquarters. Your comments will receive careful consideration at a meeting of the responsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you should make your views known to the ASTM Committee on Standards, at the address shown below. This standard is copyrighted by ASTM, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428 -2959, United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the above address or at 610 - 832 -9585 (phone), 610 - 832 -9555 (fax), or service @astm.org (e- mail); or through the ASTM website (www.astm.org). 11 'ISM Designation: D 6044 — 96 Standard Guide for Representative Sampling for Management of Waste and Contaminated Medial This standard is issued under the fixed designation D 6044; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon (e) indicates an editorial change since the last revision or reapproval. 1. Scope 1.1 This guide covers the definition of representativeness in environmental sampling, identifies sources that can affect representativeness (especially bias), and describes the at- tributes that a representative sample or a representative set of samples should possess. For convenience, the term" represen- tative sample" is used in this guide to denote both a represen- tative sample and a representative set of samples, unless otherwise qualified in the text. 1.2 This guide outlines a process by which a representative sample may be obtained from a population. The purpose of the representative sample is to provide information about a statis- tical parameter(s) (such as mean) of the population regarding some characteristic(s) (such as concentration) of its constitu- ent(s) (such as lead). This process includes the following stages: (1) minimization of sampling bias and optimization of precision while taking the physical samples, (2) minimization of measurement bias and optimization of precision when analyzing the physical samples to obtain data, and (3) minimi- zation of statistical bias when making inference from the sample data to the population. While both bias and precision are covered in this guide, major emphasis is given to bias reduction. 1.3 This guide describes the attributes of a representative sample and presents a general methodology for obtaining representative samples. It does not, however, provide specific or comprehensive sampling procedures. It is the user's respon- sibility to ensure that proper and adequate procedures are used. 1.4 The assessment of the representativeness of a sample is not covered in this guide since it is not possible to ever know the true value of the population. 1.5 Since the purpose of each sampling event is unique, this guide does not attempt to give a step by step account of how to develop a sampling design that results in the collection of representative samples. 1.6 Appendix X1 contains two case studies, which discuss the factors for obtaining representative samples. 1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the ' This guide is under the jurisdiction of ASTM Committee D34 on Waste Management and is the direct responsibility of Subcommittee D34.01.01 on Planning for Sampling. Current edition approved Nov. 10, 1996. Published January 1997. responsibility of the user of this standard to establish appro- priate safety and health practices and determine the applica- bility of regulatory limitations prior to use. 2. Referenced Documents 2.1 ASTM Standards: D 3370 Practices for Sampling Water from Closed Con - duits2 D 4448 Guide for Sampling Groundwater Monitoring Wells' D 4547 Practice for Sampling Waste and Soils for Volatile Organics' D 4700 Guide for Soil Sampling from the Vadose Zone4 D 4823 Guide for Core — Sampling Submerged, Unconsoli- dated Sediments' D 5088 Practice for Decontamination of Field Equipment Used at Nonradioactive Waste Sites6 D 5792 Practice for Generation of Environmental Data Related to Waste Management Activities: Development of Data Quality Objectives' D 5956 Guide for Sampling Strategies for Heterogeneous Wastes' D 6051 Guide for Composite Sampling and Field Subsam- pling for Environmental Waste Management Activities' 3. Terminology 3.1 analytical unit, n —the actual amount of the sample material analyzed in the laboratory. 3.2 bias, n —a systematic positive or negative deviation of the sample or estimated value from the true population value. 3.2.1 Discussion —This guide discusses three sources of bias — sampling bias, measurement bias, and statistical bias. There is a sampling bias when the value inherent in the physical samples is systematically different from what is inherent in the population. There is a measurement bias when the measurement process produces a sample value systematically different from that inherent in the sample itself, although the physical sample is s Annual Book of ASTM Standards, Vol 11.01. 3 Annual Book of ASTM Standards, Vol 11.04. 4 Annual Book of ASTM Standards, Vol 04.08. s Annual Book of ASTM Standards, Vol 11.02. e Annual Book of ASTM Standards, Vol 04.09. Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428 -2959, United States. 1 In" D 6044 itself unbiased. Measurement bias can also include any sys- tematic difference between the original sample and the sample analyzed, when the analyzed sample may have been altered due to improper procedures such as improper sample preser- vation or preparation, or both. There is a statistical bias when, in the absence of sampling bias and measurement bias, the statistical procedure produces a biased estimate of the population value. Sampling bias is considered the most important factor affecting inference from the samples to the population. 3.3 biased sampling, n —the taking of a sample(s) with prior knowledge that the sampling result will be biased relative to the true value of the population. 3.3.1 Discussion —This is the taking of a sample(s) based on available information or knowledge, especially in terms of visible signs or knowledge of contamination. This kind of sampling is used to detect the presence of localized contami- nation or to identify the source of a contamination. The sampling results are not intended for generalization to the entire population. This is one form of authoritative sampling (see judgment sampling.) 3.4 characteristic, n —a property of items in a sample or population that can be measured, counted, or otherwise ob- served, such as viscosity, flash point, or concentration. 3.5 composite sample, n —a combination of two or more samples. 3.6 constituent, n— an element, component, or ingredient of the population. 3.6.1 Discussion —If a population contains several contami- nants (such as acetone, lead, and chromium), these contami- nants are called the constituents of the population. 3.7 Data Quality Objectives, DQOs, n— qualitative and quantitative statements derived from a DQO process describing the decision rules and the uncertainties of the decision(s) within the context of the problem(s) (see Practice D 5792). 3.8 Data Quality Objective Process —a quality management tool based on the Scientific Method and developed by the U.S. Environmental Protection Agency to facilitate the planning of environmental data collection activities. The DQO process enables planners to focus their planning efforts by specifying the use of data (the decision), the decision criteria (action level), and the decision maker's acceptable decision error rates. The products of the DQO process are the DQOs (see Practice D 5792). 3.9 error n —the random or systematic deviation of the observed sample value from its true value (see bias and sampling error). 3.10 heterogeneity, n— the condition or degree of the population under which all items of the population are not identical with respect to the characteristic(s) of interest. 3.10.1 Discussion — Although the ultimate interest is in the statistical parameter such as the mean concentration of a constituent of the population, heterogeneity relates to the presence of differences in the characteristics (for example, concentration) of the units in the population. It is due to the 2 presence of fundamental heterogeneity (or fundamental error) in the population that sampling variance arises. Degree of sampling variance defines the degree of precision in estimating the population parameter using the sample data. The smaller the sampling variance is, the more precise the estimate is. See also sampling error. 3.11 homogeneity, n— the condition of the population under which all items of the population are identical with respect to the characteristic(s) of interest. 3.12 judgment sampling, n— taking of a sample(s) based on judgment that it will more or less represent the average condition of the population. 3.12.1 Discussion —The sampling location(s) is selected because it is judged to be representative of the average condition of the population. It can be effective when the population is relatively homogeneous or when the professional judgment is good. It may or may not introduce bias. It is a useful sampling approach when precision is not a concern. This is one form of authoritative sampling (see biased sampling.) 3.13 population, n— the totality of items or units of materials under consideration. 3.14 representative sample, n —a sample collected in such a manner that it reflects one or more characteristics of interest (as defined by the project objectives) of a population from which it is collected. 3.14.1 Discussion —A representative sample can be a single sample, a collection of samples, or one or more composite samples. A single sample can be representative only when the population is highly homogeneous. 3.15 representative sampling, n —the process of obtaining a representative sample or a representative set of samples. 3.16 representative set of samples, n —a set of samples that collectively reflect one or more characteristics of interest of a population from which they were collected. See representative sample. 3.17 sample, n —a portion of material that is taken for testing or for record purposes. 3.17.1 Discussion — Sample is a term with numerous mean- ings. The scientist collecting physical samples (for example, from a landfill, drum, or monitoring well) or analyzing samples considers a sample to be that unit of the population that was collected and placed in a container. A statistician considers a sample to be a subset of the population, and this subset may consist of one or more physical samples. To minimize confu- sion, the term sample, as used in this guide, is a reference to either a physical sample held in a sample container, or that portion of the population that is subjected to in situ measure- ments, or a set of physical samples. See representative sample. 3.17.1.1 The term sample size also means different things to the scientist and the statistician. To avoid confusion, terms such as sample mass /sample volume and number of samples are used instead of sample size. 3.18 sampling error— the systematic and random devia- tions of the sample value from that of the population. The Pitard, F. F., "Pierre Gy's Sampling Theory and Sampling Practice: Heteroge- neity, Sampling Correctness and Statistical Process Control," 2nd ed., CRC Press Publishers, 1993. 4111 D 6044 systematic error is the sampling bias. The random error is the sampling variance. 3.18.1 Discussion — Before the physical samples are taken, potential sampling variance comes from the inherent popula- tion heterogeneity (sometimes called the "fundamental error," see heterogeneity). In the physical sampling stage, additional contributors to sampling variance include random errors in collecting the samples. After the samples are collected, another contributor is the random error in the measurement process. In each of these stages, systematic errors can occur as well, but they are the sources of bias, not sampling variance. 3.18.1.1 Sampling variance is often used to refer to the total variance from the various sources. 3.19 stratum, n —a subgroup of the population separated in space or time, or both, from the remainder of the population, being internally similar with respect to a target characteristic of interest, and different from adjacent strata of the population. 3.19.1 Discussion —A landfill may display spatially sepa- rated strata, such as old cells containing different wastes than new cells. A waste pipe may discharge into temporally sepa- rated strata of different constituents or concentrations, or both, if night —shift production varies from the day shift. In this guide, strata refer mostly to the stratification in the concentrations of the same constituent(s). 3.20 subsample, n— a portion of the original sample that is taken for testing or for record purposes. 4. Significance and Use 4.1 Representative samples are defined in the context of the study objectives. 4.2 This guide defines the meaning of a representative sample, as well as the attributes the sample(s) needs to have in order to provide a valid inference from the sample data to the population. 4.3 This guide also provides a process to identify the sources of error (both systematic and random) so that an effort can be made to control or minimize these errors. These sources include sampling error, measurement error, and statistical bias. 4.4 When the objective is limited to the taking of a representative (physical) sample or a representative set of (physical) samples, only potential sampling errors need to be considered. When the objective is to make an inference from the sample data to the population, additional measurement error and statistical bias need to be considered. 4.5 This guide does not apply to the cases where the taking of a nonrepresentative sample(s) is prescribed by the study objective. In that case, sampling approaches such as judgment sampling or biased sampling can be taken. These approaches are not within the scope of this guide. 4.6 Following this guide does not guarantee that represen- tative samples will be obtained. But failure to follow this guide will likely result in obtaining sample data that are either biased or imprecise, or both. Following this guide should increase the level of confidence in making the inference from the sample data to the population. 4.7 This guide can be used in conjunction with the DQO process (see Practice D 5792). 4.8 This guide is intended for those who manage, design, and implement sampling and analytical plans for waste man- 3 agement and contaminated media. 5. Representative Samples 5.1 Samples are taken to infer about some statistical param- eter(s) of the population regarding some characteristic(s) of its constituent(s) of interest. This is discussed in the following sections. 5.2 Samples —When a representative sample consists of a single physical sample, it is a sample that by itself reflects the characteristics of interest of the population. On the other hand, when a representative sample consists of a set of physical samples, the samples collectively reflect some characteristics of the population, though the samples individually may not be representative. In most cases, more than one physical sample is necessary to characterize the population, because the popula- tion in environmental sampling is usually heterogeneous. 5.3 Constituents and Characteristics —A population can possess many constituents, each with many characteristics. Usually it is only a subset of these constituents and character- istics that are of interest in the context of the stated problem. Therefore, samples need to be representative of the population only in terms of these constituent(s) and characteristic(s) of interest. A sampling plan needs to be designed accordingly. 5.4 Parameters — Similarly, samples need to be representa- tive of the population only in the parameter(s) of interest. If the interest is only in estimating a parameter such as the population mean, then composite samples, when taken correctly, will not be biased and therefore constitute a representative sample (regarding bias) for that parameter. On the other hand, if the interest happens to be the estimation of the population variance (of individual sampling units), another parameter, then the variance of the composite samples is a biased estimate of the population variance and therefore is not representative. (It is to be noted that composite samples are often used to increase the precision in estimating the population mean and not to estimate the population variance of individual sampling units.) 5.5 Population —Since the samples are intended to be rep- resentative of a population, a population must be well defined, especially in its spatial or temporal boundaries, or both, according to the study objective. 5.6 Representativeness —The word "reflects" in this guide is used to mean a certain degree of low bias and high precision when comparing the sample value(s) to the population val- ue(s). This is a broad definition of sample representativeness used in this guide. A narrower definition of representativeness is often used to mean simply the absence of bias. 5.6.1 Bias —Bias is sometimes mistakenly taken to be "a difference between the observed value of a physical sample and the true population value." The correct definition of bias is "a systematic (or consistent) difference between an observed (sample) value and the true population value." The word "systematic" here implies "on the average" over a set of physical samples, and not a single physical sample. Recall that sampling error consists of the random and systematic devia- tions of a sample (or estimated) value from that of the population. Although random deviations may occur on occa- sions due to imprecision in the sampling or measurement processes, or both, they balance out on the average and lead to no systematic difference between the sample (or estimated) �S1M D 6044 value and the population value. The random deviation corre- sponds to the observation of "a random difference between a single physical sample value and the true population value," which can be randomly positive or negative, and is not a bias. On the other hand, a persistent positive or negative difference is a systematic error and is a bias. 5.6.1.1 In order to assess bias, the true population value must be known. Since the true population value is rarely known, bias cannot be quantitatively assessed. However, this guide provides an approach to identifying the potential sources of bias and general considerations for controlling or minimiz- ing these potential biases. 5.6.2 Precision — Precision has to do with the level of confidence in estimating the population value using the sample data. If the population is totally homogeneous and the mea- surement process is flawless, a single sample will provide a completely precise estimate of the population value. When the population is heterogeneous or the measurement process is not totally precise, or both, a larger number of samples will provide a more precise estimate than a smaller number of samples. 5.6.2.1 In the case of bias, the goal in environmental sampling is its absence. In the case of precision, the goal in sampling will depend on factors such as: (1) The precision level needed to achieve the desired levels of decision errors, both false positive and false negative errors, (2) If the true value is known or suspected to be well below the regulatory limit, high precision in the samples may not be needed, and (3) The study budget. 5.6.2.2 Note that the second item applies similarly to bias as well. 5.6.2.3 Since bias, especially during sampling, can be very large when proper procedures are not followed, it is considered to be the first necessary condition for sample representative- ness. On the other hand, precision can be more or less controlled, for example, by increasing the number of samples taken or by decreasing the sampling or measurement variabili- ties, or both. 5.6.2.4 The optimal number of samples to take to achieve a desired level of precision is typically an issue in optimization of a sampling plan. Therefore, the precision issue will be covered only briefly in this guide. 6. A Systematic Approach to Representative Sampling 6.1 A systematic approach is one that first defines the desired end result and then designs a process by which such a result can be obtained. In representative sampling, the desired end result is a sample or a set of samples that achieves desired levels of low bias and high precision. 6.2 A representative sampling process is described in Fig. 1. The key components in the process are described in this section. 6.3 Study Objective— A sampling plan is designed accord- ing to a defined problem or a stated study objective. The samples are then collected according to the sampling plan. Generally, the study objective dictates that representative samples be taken for the purpose of inference about the population. In that case, these samples will need to be collected according to this guide in order for the inference to be valid. 4 Representative Samples Study Objective Population a. Spatial & temporal boundaries b. Sampling unit c. Constituent/Property of interest d. Statistical parameter of interest Sampling Design No. of samples (In optimization) V a. Sampling Equipment & Procedures b. Statistical Sampling Principles Representative Set of Sample(s) Sample Preservation to minimize sampling bas V Representative Subsample Minimize subsampling bias Sample Preservation V Chemical Analysis Correct measurement process to minimize measurement bias Statistical Analysis Correct inference procedure to minimize statistical bias FIG. 1 A Systematic Approach to Representative Sampling Occasionally, the objective is merely to detect the presence of a contaminant or to obtain a "worst case" sample. In that case, an authoritative sampling approach (biased sampling or judg- ment sampling) may be taken and this guide does not apply. 6.4 Population —A population consists of the totality of items or units of materials under consideration (Compilation of ASTM Standard Definitions, 1990). Its boundaries (spatial or temporal, or both) are defined according to the problem statement. This population is usually called the target popula- tion. In order to solve the stated problem, samples must be taken from the target population. 6.4.1 Sampled Population— Sometimes some parts of the target population may not be amenable to sampling due to factors such as accessibility. The boundaries of the target population actually sampled due to factors such as incomplete accessibility define the sampled population. 6.4.1.1 Although the samples taken from the sampled popu- lation may be representative of the sampled population, they may not be representative of the target population. In this case, potential exists that the samples taken from the sampled population may systematically deviate from the true value of the target population, thereby introducing bias when making inference from the samples to the target population. 6.4.1.2 When the boundaries of the target and sampled populations are not identical, some possible solutions are: (1) The parties to the decision — making may agree that the In" D 6044 sampled population is a sufficient approximation to the target population. A sampling plan can then be designed to take representative samples from the" sampled population," (2) Qualifications on the sampling results are made based on the differences between the two populations. Some profes- sional judgment may have to be exercised here, and (3) Redefine the problem by considering what problem is solvable based on the observed differences between the two populations. 6.4.1.3 Occasionally, the sampled population is chosen on purpose to be different from the target population. For ex- ample, an investigator may be interested in the lead content in the sludge of a surface impoundment (the target population). He may decide to take samples from the sludge near the inlet (sampled population). Thus, the impoundment is the target population, while the inlet area is the sampled population. If the interest is in the target population, then this is an example of a biased sampling approach. On the other hand, the involved parties may decide to redefine the target population to include only the inlet area. Then the target population and the sampled population are identical. Again, the definition of a population depends on the problem statement. 6.4.1.4 In yet other circumstances, an investigator may take only a sample from the population. The following cases are possible: (1) This one physical sample can be a sample from a biased sampling approach, for the purpose of detecting the presence of a contaminant or identifying the source of contamination. Therefore, it is not a representative sample due to its bias, (2) This one physical sample can be a sample from judgment sampling, for the purpose of estimating the average condition of the population. Bias may or may not exist depending to some degree on the expertise of the sampler, (3) This sample can be viewed as a population itself if the investigator is interested in the sample alone and a result from this sample is not to be used to infer to areas outside the sample. In this case, no bias exists, and (4) If this sample is the composite of a few samples taken from the population, bias is likely to be minimal if the original samples are carefully taken. 6.4.2 Decision Unit— Often a population may be divided into several exposure units, cleanup units, or strata. If the environmental management decision is to be made for the entire population as a whole, representative samples can be obtained by designs such as a stratified random sampling design. Here the entire population is the decision unit. On the other hand, if the decision is to be made on each unit or stratum, then each unit or stratum is the decision unit. In this case, representative sample(s) need to be taken from each unit or stratum as if the unit or stratum is the population. 6.4.2.1 If the units or strata are relatively small in size or too numerous to take many samples per unit or stratum, composite sample(s) can be taken from each unit or stratum to increase precision without introducing bias. Alternatively, if precision is not a concern and there is sufficient professional expertise to avoid bias, a judgment sample(s) can be taken from each unit or stratum. 6.4.3 Heterogeneity— Heterogeneity is discussed in greater 5 detail in Guide D 5956. 6.4.3.1 The degree and extent of population heterogeneity affect potential bias and precision in the samples. Population heterogeneity can be viewed at least in three different ways: (1) When the population is heterogeneous in a random manner in only the distribution of the concentration, but not in the physical materials such as particle sizes, designs such as a simple random sampling design will generally produce samples with minimal bias. Its precision will then depend on the number of samples taken, (2) When the population is randomly heterogeneous in concentrations due to large differences in the materials such as particle size, a simple random sampling design may still be effective if the sample volume /weight and sampling equipment are chosen to accommodate the largest particles and thereby prevent introduction of bias, and (3) If the population is systematically heterogeneous, such as the presence of stratification in concentrations, then a simple random sampling design may not be biased, but will be less precise than an alternative design such as stratified random sampling. 6.4.3.2 Heterogeneity in the population affects the sampling variance. Sampling variance is a function of factors such as the population heterogeneity and the sample volume or weight. It is clear that the more heterogeneous the population is, the larger the inherent sampling variance is. It is also clear that samples of smaller volume or weight will have a higher sampling variance than those with greater volume or weight. However, the reduction in sampling variance due to increased volume or weight may eventually reach a limit Determination of the optimal sample volume or weight is beyond the scope of this guide.' 6.4.3.3 The proper procedure is to first determine the right sample volume or weight, then to determine the number of samples needed for the chosen sample volume or weight. 6.4.3.4 Since stratification as a phenomenon of population heterogeneity is fairly common, it is discussed in greater details as follows. 6.4.4 Stratification— There are generally three types of stratification affecting sample representativeness. One is a stratification in the distribution of the contaminant concentra- tion distribution alone. The second is a stratification in sam- pling materials or matrices alone. The third is a combination of both types. Stratification of any type is not a big problem regarding sample representativeness if each stratum is a decision unit. In that case, the units in a stratum are by definition relatively similar, apart from the random variations in concentrations. A simple random sampling design can be used to obtain representative samples (unbiased) for each stratum. The question of sample representativeness becomes more complicated when a decision is to be made over all the strata in the population. 6.4.4.1 A Single Representative Sample in A Stratified Population —When the objective is to obtain a single (physi- cal) representative sample of all the strata, the sample must be a composite of individual samples from the strata (for example, at least one individual sample per stratum). Here the volumes or weights of the individual samples should be proportional to �S1M D 6044 the relative stratum sizes. The composite sample so obtained would be unbiased. However, since there is only one composite sample, precision of the composite sample cannot be estimated. If there are existing data on the precision of the individual samples in the strata, then the precision of the composite sample can be inferred from the precision of the individual samples by theoretical or empirical relationship. See Guide D 6051. 6.4.4.2 A Representative Set of Samples —When the popu- lation is stratified, a set of samples obtained by statistical designs such as stratified random sampling, where the number of samples to be taken from the strata are proportional to the relative sizes of the strata, is unbiased and more precise than a set of samples taken without considering the stratification. 6.4.5 Parameter(s) of Interest —This refers to the statistical parameter such as mean or variance of the population. It is often used with a characteristic such as concentration of a constituent(s) of the population. An example is the mean (parameter) concentration (characteristic) of lead (constituent). Another example is a population of mixture of silt —size calcium carbonate particles and large cobble —size particles of calcium carbonate. The interest here could be in the mean (parameter) particle size or chemical composition (characteristic) of cal- cium carbonate (constituent), depending on the study objective. 6.5 Develop A Sampling Design —The objectives of a sam- pling design are to minimize bias and achieve a desired level of precision. Precision and bias are an issue at various stages of the process of inferring from the samples to the population. The first stage is the act of obtaining the physical samples. The second stage is the act of analyzing the physical samples and translating them into data. The third stage is the use of statistical method to infer from the sample data to the popula- tion. At the first stage, the main concerns are sampling precision and bias. At the second stage, the concerns are measurement of precision and bias. At the third stage, the concern is statistical bias. 6.5.1 At the first stage of obtaining physical samples, the issues of precision and bias are sometimes grouped together as sampling design issues. 6.5.2 Bias at this stage is often called the sampling bias. Sampling bias is the systematic difference between the value inherent in the physical samples and the true population value. The word "inherent" is used because at this point the physical samples have not been translated into data. 6.5.3 The phrase "systematic difference" implies a persis- tent difference in long —term average or expectation, not the occasional random difference. Representative samples, apart from the issue of precision, are obtained when this long —term expected difference is zero or nearly so. 6.5.4 Since the true population value is typically not known, sampling bias cannot be assessed. However, efforts to mini- mize sampling bias can be attempted in at least two areas: 6.5.4.1 Proper Statistical Sampling Design— Statistical sampling design has to do with where and how samples are to be taken, where equal probability of selecting any of the units or items in the population is often a primary requirement. If the probability of selection is not equal, it is highly likely that bias will have been introduced into the physical samples so ob- 6 tained. Depending on the layout of the population, designs such as simple random sampling or stratified random sampling can be used. 6.5.4.2 Proper Sampling Procedures and Sampling Equipment —This includes proper procedures for compositing, subsampling, sample preparation and preservation, and proper use of the chosen sampling equipment. This is a major source affecting precision and bias, especially bias. 6.5.5 In the case of precision, it can be controlled by things such as the number of samples taken, the use of composite samples, or more precise sampling techniques. Often, the number of samples to take is considered the key design issue. Some considerations regarding precision are: 6.5.5.1 If a population is relatively small compared to the sample mass /volume and the distribution of the characteristic of interest is random, it may be appropriate to collect a smaller number of samples by a random or systematic sampling approach, and 6.5.5.2 If a population is relatively large compared to sample mass /volume and the characteristic of interest is not randomly distributed (for example, stratified), a greater number of samples and a stratified sampling approach may be needed. 6.5.6 Compositing— Compositing is the combination of two or more individual physical samples into a single sample. It is often used to reduce the analytical costs, while maintaining or increasing precision relative to the individual samples (see Guide D 6051). Bias may or may not be introduced in compositing, depending on the study objective and the physical means of compositing. For example: 6.5.6.1 If the study calls for the estimation of the population variance (or standard deviation) of individual samples, then composite samples will surely underestimate the population variance, and 6.5.6.2 If the physical means of compositing changes the characteristics of the samples, then bias may have been introduced (unless such changes are part of the study design). 6.6 Subsampling— Sampling bias can be introduced in subsampling unless the same proper sampling protocol is followed as in taking samples from the original population. 6.6.1 Discussion —After the physical samples have been obtained and before they are measured, bias can be prevented by following proper sample preservation and preparation procedures. It is not important whether these procedures are viewed as part of the sampling process or as part of the measurement process. It is only important in following the proper procedures to prevent bias. 6.7 Measurement of Precision and Bias: 6.7.1 The measurement process, like the sampling process, also consists of a random error and a systematic error. The random errors define the degree of measurement precision, and the systematic error defines the degree of measurement bias. 6.7.2 Like sampling precision, measurement precision is controlled by things such as the number of replicate analyses performed per sample and refinements of the analytical method. 6.7.3 Measurement bias is a systematic difference between the sample value produced by the measurement process and the true population value, assuming that the physical samples are In" D 6044 unbiased before the analysis. The bias can come from contami- nation, loss or alteration of the sample materials, systematic errors in the measurement device, or from systematic human errors. 6.7.4 Often the measurement bias can be reasonably esti- mated in a laboratory testing setting when the true value is known. Laboratory samples spiked with known quantities of a chemical or certified reference standard can often be used to assess potential measurement bias. Minimization or adjustment for such estimable bias in the measurement process is essential in order to obtain data that are unbiased. When estimation of bias is not possible, care in measurement protocol and training is probably the only recourse. 6.7.4.1 Discussion —It is important to note that, when infer- ring from the sample data to the population, all the sources of imprecision, including sampling, subsampling, and measure- ment, need to be combined. The process of accumulating these sources of variation is sometimes called the "propagation of errors." The determination of the optimal numbers of samples, subsamples, and replicates are an issue of optimization and is not covered in this guide. 6.8 Statistical Bias— Statistical bias can result from an inappropriate sampling design or inappropriate estimation procedures, or both: 6.8.1 Selection Bias from Sampling Design —In the course of taking the sample, if the population units do not have the same probability of being selected, bias can be introduced. This bias can be prevented or minimized when a statistical sampling design is carefully selected, based on the study objective and the layout of the population. Some possible designs are the simple random sampling design and the stratified random sampling design. 6.8.2 Estimation of Bias from Estimation Procedures —This bias occurs when the expected value of the statistical estimator does not equal the true value. 6.8.2.1 Estimation bias can occur when the wrong statistical distribution of the data is used. For example, if the normal distribution assumption is used when the true data distribution is lognormal, the interval estimate of the mean concentration will be an biased estimate against the true interval. Thus, the expected value of the estimator will not be equal to the true value. To avoid this potential bias, it is wise to check the data distribution. 6.8.2.2 Estimation bias can also occur when a wrong statis- tical estimator is used. For example, if the sum of squares of deviations from the sample mean divided by the number of samples (that is, Ei =1,n (x, — x)Z /n) is used to estimate the population variance, then this estimator is biased (its math- ematical expected value is not equal to the population vari- ance). If its denominator is modified to be (n —1), then it is an unbiased estimator. For an unbiased statistical estimator, the reader is advised to check with a statistician. 7. Attributes of Representative Samples 7.1 The attributes of a representative (physical) sample or a representative set of (physical) samples can be described in the chronological order in which samples are taken. Note that these attributes apply only to how representative the physical 7 samples are of the population. This corresponds to the upper half of Fig. 1. 7.2 Design Considerations: 7.2.1 A well— defined target population. The target popula- tion includes all the population units as determined from the stated problem. 7.2.2 The sampled population equals the target population in their spatial or temporal boundaries, or both. The sampled population consists of the population units directly available for measurement.' 7.2.2.1 When all the population units in the target popula- tion are accessible and directly available for measurement, then the sampled population is identical to the target population in its spatial or temporal boundaries, or both. 7.2.2.2 When not all the population units are directly available for measurement, then the inference from the sample is made to the sampled population, not the target population. 7.2.3 Size (weight or volume) of the sampling unit is well defined. 7.2.3.1 The population can be divided into various sizes (weight or volume) of population units. The size of the sampling unit is the size of the population unit most appropri- ate for the sampling purposes. 7.2.3.2 The appropriate size of the sample is determined by degree of heterogeneity of the materials to be sampled, such as particle size or shape. 7.3 Sampling and Measurement Considerations: 7.3.1 Correct sampling procedures are followed to minimize sampling bias. 7.3.1.1 Absence or minimization of bias is a key attribute of representative samples. Sampling bias can be minimized by following correct sampling procedures. Correct sampling pro- cedures have two components. (1) A sampling procedure that maximizes the potential of population units having equal probability of selection as sampled, and (2) Correct sampling procedures. This includes the selec- tion of appropriate equipment and proper use of that equip- ment. 7.3.2 Sample integrity is maintained during sampling and before chemical analysis. 7.3.3 If subsampling is performed, correct sampling proce- dures are followed to minimize sampling bias. 7.3.4 Sample preparation errors such as contamination and loss or alteration of constituents are prevented or minimized. 7.3.5 The samples, in the end, collectively reflect the target population within the context of the problem. 7.3.6 These attributes can be summarized into three broad categories: 7.3.6.1 A well— defined population, 7.3.6.2 Correct sampling procedures, and 7.3.6.3 Samples collected in the context of the stated prob- lem. $ Gilbert, Richard 0., Statistical Methods for Environmental Pollution Monitor- ing, Van Nostrand Reinholt Co., New York, NY 1987. �S1M D 6044 sion of sampling ground water refer to Guide D 4448. 8.3.1.1 Ground —water samples are usually collected through an in —place well, either temporarily or permanently installed. The following is a list of concerns that should be considered when collecting a ground —water sample. (1) The well should be purged before collecting samples in order to clear the well of stagnant water which is not representative of aquifer conditions. Purging and sampling rates can cause chemical or physical changes in the water. (2) Purging can be performed in such a way that the entire column of water is not removed. The best method for avoiding this situation is by lowering a pump or bailer into the top of the column of water. (3) Bailing may stir up sediment in the well if conducted too vigorously. Increased turbidity can result in a higher metal content in the sample than in a non — turbid sample. (4) Samples for volatile organic analysis should be col- lected in a fashion that minimizes agitation of the sample. (5) Wells with in —place plumbing must also be purged. Samples should be collected immediately following purging. In order to collect a sample representative of ground water, samples should be collected before the water travels through any hoses or in —line treatment devices. 8.3.2 Surface Water and Sediment —For a more comprehen- sive discussion of sampling surface water and sediment, refer to Practice D 3370 and Guide D 4823. General and specific sampling concerns for collection of surface water and sediment samples are as follows: 8.3.2.1 General Considerations: (1) Although bridges and piers may provide access for water and sediment sampling, these structures can also alter the nature of water flow and thus influence sediment deposition or scouring. Depending on the construction materials, these structures can contaminate samples collected in the immediate vicinity. (2) Wading for water samples should be done with caution since bottom deposits are easily disturbed resulting in in- creased sediment in surface water samples and a removal of fines from the sediment sample. 8.3.2.2 Rivers, Streams, and Creeks: (1) A good location to collect a vertically mixed surface water sample is immediately downstream of a riffle area. This location is also a likely area for deposition of sediment since the greatest deposition occurs where stream velocity slows down. (2) Horizontal (cross — channel) mixing occurs in constric- tions in the channel. However, this is a poor sediment sample collection area because of scouring. (3) Surface water samples will be affected by point sources, such as tributaries and industrial and municipal effluents. (4) Locations immediately upstream or downstream from the confluence of two streams or rivers may not immediately mix, and at times, due to possible back flow, can upset the normal flow patterns. (5) Unless a stream is extremely turbulent, it is nearly impossible to measure the effect of a waste discharge or tributary immediately downstream of the source. Inflow fre- quently "hugs" the stream bank with very little cross — channel 8. Practical Considerations 8.1 Sampling Equipment —The choice of appropriate sam- pling equipment can be crucial to the task of collecting a representative sample or a representative set of samples. Depending on the goals of the sampling activity, the sampling device used should minimize bias by having certain character- istics and capabilities, such as: 8.1.1 The ability to access and extract from every location in the target population, 8.1.2 The ability to collect a sample of proper shape, 8.1.3 The ability to collect a sufficient mass or volume of sample such that the distribution of particle sizes in the population are represented, and 8.1.4 The ability to collect a sample without the addition or loss of contaminants of interest. 8.2 Equipment Design— The improper design of sampling equipment may result in the collection of samples that are not representative of the population. 8.2.1 An example of equipment design influencing sam- pling results is samplers which exclude certain sized particles from a soil matrix or waste pile sample. The shape of some scoops may influence the distribution of particle sizes collected from a sample. Dredges used to collect river or estuarine sediments may also exclude certain sized particles, particularly the fines fraction which may contain a significant percentage of some contaminants such as polynuclear aromatic hydrocarbons (PAHs). Specific considerations in equipment design are out- lined as follows. 8.2.1.1 Sample Volume Capabilities —Most sampling de- vices will provide adequate sample volume. However, the sampling equipment volumes should be compared to the volume necessary for all required analyses and the additional amount necessary for quality control (QC), split and repeat samples. Taking more than one aliquot to obtain an adequate sample volume can impact the representativeness of a sample. 8.2.1.2 Compatibility It is important that sampling equip- ment, other equipment that may come in contact with samples (such as gloves, mixing pans, knives, spatulas, spoons, etc.) and sample containers be constructed of materials that are compatible with the matrices and analytes of interest. Incom- patibility may result in the contamination of the sample and the degradation of the sampling equipment. 8.2.1.3 Decontamination (see Practice D 5088) and Reuse — Inadequate decontamination of sampling equipment can result in contamination of the sample and affects its representativeness. Due to design, some equipment is very difficult to adequately decontaminate. In some instances, it may even be desirable to either dispose of sampling equipment after use or to dedicate the equipment to a sampling point. 8.3 Sampling Procedure — Inappropriate use of sampling equipment is one of the largest sources of sampling bias. While it is beyond the scope of this guide to discuss it in depth, examples of how bias can be introduced during the sampling procedure are discussed in the following paragraphs. This guide does not provide comprehensive sampling procedures. It is the responsibility of the user to ensure that proper and adequate procedures are used. 8.3.1 Ground Water— For a more comprehensive discus- 8 �S1M D 6044 mixing for some distance. Samples from quarter points across a stream may miss the wastes altogether and reflect only the quality of water upstream from the waste source. Samples collected within the portion of the cross section containing the wastes would indicate excessive effects of the wastes with respect to the river as a whole. (6) When sampling tributaries, care should be exercised to avoid collecting water from the main stream that may flow into the mouth of the tributary on either the surface or bottom. 8.3.2.3 Lakes, Ponds, and Impoundments: (1) Stratification of surface water is of greater concern in standing water. For example: A turbidity difference may occur vertically where a highly turbid river enters a lake, and each layer of the stratified water column may need to be considered. In addition, stratification may be caused by water temperature difference; cooler, heavier river water is beneath the warmer lake water. (2) Dredges used to collect sediment samples can displace and miss lighter materials if allowed to drop freely. (3) Core samplers used to sample vertical columns of sediment are useful when there is a need to know the history of sediment deposition. Coring devices also minimize the distur- bance of fines at the sediment —water interface. However, coring devices can only sample a relatively small surface area. Depending on the core diameter, larger particles may be excluded and a single aliquot may not be sufficient for analytical needs. 8.3.3 Soils —For more detailed information, refer to Practice D 4547 and Guide D 4700. General areas of concern for sampling soils are as follows: 8.3.3.1 Soil samples for purgeable organic analyses should be collected with a minimum disturbance of the sample. 8.3.3.2 Samples for VOA analysis should not be mixed. 8.3.3.3 Two potential problems are associated with compos- iting soil samples. Low concentrations of contaminants present in individual aliquots may be diluted to the extent that the total composite concentration is below the minimum quantification limit. In addition, depending on the soil type, it can be very difficult to produce a homogeneous mixture. 8.3.4 Waste — Wastes referred to in this section include any liquid, solid, or sludge from pits, ponds, lagoons, waste piles, landfills, and open or closed containers such as drums, tank trucks, and storage tanks. 8.3.4.1 Any of these units may have multiple phases (float- ing solids, different density liquid phases, and sludge) and one or all of them may need to be sampled. 8.3.4.2 If sampling from access valves or ports on an open or closed container, care should be taken to be sure that the desired layer is sampled. For example, bottom sampling ports would allow only the heavier contents to be sampled while surface or top sampling would allow only sampling of the lighter layers. 8.4 Subsampling (Field): 8.4.1 Different analyses require different types of bottles and preservation. For multiple analyses of the same waste stream, this may require subsampling in the field. Subsampling in the laboratory may require many of the same procedures; however, laboratory subsampling is beyond the scope of this guide. 8.4.1.1 Samples for organic analyses should always be taken from the first material collected. This minimizes loss of volatile organics during handling of the material. 8.4.1.2 If necessary, place the appropriate volume of mate- rial in a tray or other suitable container to composite. The volume is dependent on the needed analyses, and should be specified by the analytical laboratory. 8.4.1.3 Transfer the material into the required containers for analyses. If subsampling takes place, then the analytical sample is the final portion of the material subsampled from the original sampling unit and analyzed in the laboratory. 8.4.2 In subsampling, the original sampling unit can be considered as the population and the correct sampling proce- dures must be followed to ensure a representative subsample 9. Keywords 9.1 bias; contaminated media; precision; representative; sample; waste; waste management APPENDIX (Nonmandatory Information) Xl. TWO CASE STUDIES OF REPRESENTATIVE SAMPLING X1.1 Case Study One —Waste Pile Investigation X1.1.1 Background— An industrial facility has managed recovery furnace slag and baghouse dust in a waste pile located on the site. No active management was occurring with the waste pile. No buried containers or extremely heterogenous material (debris) was suspected of being present in the waste pile based on facility records and interviews of personnel. X1.1.1.1 Lead and cadmium were the constituents of con- cern based on process knowledge, and the possibility for the waste being hazardous by means of the Toxicity Characteristic (TC) Rule was the regulatory consideration. No preliminary 9 information on the variability of lead and cadmium within the piles was available. The potential for off —site migration of contaminants by means of a drainage ditch that leads to a stream adjacent to the facility was an immediate concern. X1.1.2 Phase 1: Objective —The primary objective of the initial investigation was to determine if the slag and baghouse dust in the waste piles were characteristic for lead via the Toxicity Characteristic Rule. A secondary objective was to provide preliminary information on potential migration and transport of contaminants from the waste piles off site. X1.1.2.1 The sampling design for this initial investigation 4111 D 6044 utilized a judgmental sampling strategy to provide a prelimi- nary estimate of the lead and cadmium concentrations in the waste pile, the variability of contaminant concentrations in the pile, and the potential for leaching using the TCLP. Four areal composite samples were collected from the surface (0 to 6 in.) at the four quadrants of the waste pile. Borings were completed at the center of each area that was sampled on the surface. Each four —foot interval was analyzed to assess vertical variability. X1.1.2.2 The following environmental samples were also collected using a judgmental approach: (1) Several soil samples in the vicinity of the waste pile, (2) Sediment upstream and downstream in a stream that borders the facility, (3) Sediment in a ditch which contained run —off from the pile, and (4) Two background soil samples. X1.1.2.3 Results —Zinc, copper, cadmium, and lead were all elevated (compared to background) in the samples collected from the waste piles. Since lead and cadmium are TC Rule constituents, the TCLP was completed, and the lead results exceeded the regulatory level of 5 mg/L. Cadmium was just under the regulatory level of 1.0 mg/L. Lead and cadmium concentrations in the soil near the waste piles were 2 to 3 times above background, and the drainage ditch and downstream sediment sample also had elevated lead and cadmium levels. X1.1.2.4 Conclusion— The waste piles contain slag and baghouse dust that is hazardous for lead. The waste pile requires further characterization to determine the variability in the pile. The presence of lead and cadmium in soils and the stream sediment downstream of the facility was confirmed and should be further investigated to determine the extent of contaminant transport. X1.1.3 Phase 2: Objective —The sampling design utilized a systematic grid approach. This design will delineate horizontal and vertical variability in lead and cadmium concentrations. The Phase 1 investigation also provided a good estimate of the anticipated variability in the waste pile. X1.1.3.1 The number of samples required to adequately characterize the waste pile was calculated based on the anticipated variability, the regulatory level of concern, and the specified confidence interval. The grid sizes were then adjusted to accommodate the projection on the required number of samples. Composite samples were collected within each grid cell based on one center point and eight points on the compass (45 deg intervals) equidistant from the center point. X1.1.3.2 Twenty percent of the grids were designated for vertical characterization (at the grid center) at four —foot inter- vals, as well as surface (0 to 6 in.) sample collection. Additionally, ten percent of the grids were randomly desig- nated for duplicate sampling (using a different aliquot pattern within the cell) to check the preliminary estimate on the variability. X1.1.3.3 Additional environmental sampling was conducted that included a systematic sampling design for the stream adjacent to the facility with sediment samples collected at 100 —ft intervals. A systematic approach was also used for the 10 drainage ditch (50 —ft intervals), with judgmental samples being collected at any location where visible staining was observed. X1.1.3.4 Results —The results supported the initial investi- gation with lead consistently exceeding the TC Rule regulatory level; cadium was consistently below the regulatory level. Vertical differences in the lead and cadmium concentrations were not significant. Lead and cadmium were detected at elevated concentrations (relative to background) in the adjacent stream at a point downstream of the confluence with the drainage ditch. X1.1.3.5 Conclusion— The waste pile was characteristic for lead and subject to Subtitle C of RCRA. There was no significant variability with depth, although several gradients were noticed across the grid (horizontally) based on lead concentration (scan) results. X1.2 Case Study Two —Drum Sampling X1.2.1 Background— An industry has two areas where drums of waste have been stored. One area is a warehouse adjacent to an off—line plating process that contains less than 25 drums (55 gal). The drums have manufacturers' labels indicat- ing they contain an acid solution, and all of the drums are similar in appearance. A second area is a covered shed that has an estimated 100 drums from a variety of processes, several of which are no longer in use at the facility. Information on the content of these drums is not available. X1.2.2 Objective —The objective of the initial investigation was to survey both of the storage areas for safety purposes, assess and record information on the drums, and open drums that were candidates for screening. All drums that were opened were surveyed using an organic vapor analyzer (PID, FID), pH paper, halogen detector, cyanide detector, and radiation meter. X1.2.2.1 A judgmental sampling design was utilized in the warehouse where the anticipated variability was low. Based on the site screening (pH measurement), six samples were col- lected for pH analysis from the warehouse. X1.2.2.2 The drums in the shed were screened in a similar fashion. A variety of results were obtained which included elevated pH, high organic vapor readings, and so forth. A simple random sampling design was used which called for the collection of 15 samples, with five from each major group of drums based on the screening (five corrosives, five potential ignitables with no halogens, and five with elevated halogen readings). X1.2.2.3 Results —The warehouse samples were all corro- sive with pH values from 1 to 2 S.U. The shed samples resulted in the collection of five corrosive wastes, three that were both ignitable and characteristic for non — halogenated TC Rule constituents, and two that were ignitable and characteristic for halogenated constituents. In summary, of the 15 drums sampled, 10 contained hazardous waste. X1.2.2.4 Conclusions— All of the drums in the warehouse are subject to Subtitle C of RCRA. The drums in the shed require further assessment due to the fact that several of those sampled did not contain hazardous waste. In" D 6044 The American Society for Testing and Materials takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility. 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Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the above address or at 610 - 832 -9585 (phone), 610- 832 -9555 (fax), or service @astm.org (e- mail); or through the ASTM website (www.astm.org). 11 OPERATION AND MAINTENANCE COMPLIANCE PLAN Piceance Centralized Soil Treatment Facility Garfield County, Colorado APPENDIX E Prepared by: PDC Energy, Inc. Denver, Colorado L El Mountain States ACCUTEST. L;•t,•a .,t es ACCUTEST LABORATORIES 1956- 2006 Technical Report for r PDC PDC -PC5 & GG2 Profile Sampling Accutest Job Number: D13026 Sampling Date; 05/04/10 Report to: HRL Compliance Solutions Inc. 744 Horizon Court Suite 140 Grand Junction, CO 81506 hlucero chi hrlcomp, com ATTN: Herman Lucero Total number of pages in report: 48 Test results contained within this data package meet the requirements of the National Environmental Laboratory Accreditation Conference and/or state specific certification programs as applicable, Client Service contact; Shea Greiner 303 -425 -6021 e- Hardcopy 2.0 Automated Report 05/12/10 Jesse L. Smith Laboratory Director Certifications: CO, ID, NE, NM, NO (R -027) (PW) UT (NELAP CO00049) This report shall not be reproduced, except in its entirety, without the written approval ofAecutest Laboratories. Test results relate only to samples analyzed, Mountain States • 4036 Ynungfield St. • Wheat Ridge, CO 80033 -3962 • tell 303 - 425 -6021 • fax: 303- 425 -6854 • http: / /www,accutest,eam 1 of 48 ®ACCUTEST. D13026 to G•:,itoi.� Accutest Laboratories is the sole authority for authorizing edits or modifications to this document. Unauthorized modification of this report is strictly prohibited, Table of Contents -1- Section 1: Sample Summary 3 Section 2: Case Narrative /Conformance Summary 4 a cciimi l era lt<> ...............................<..,......... ......,,,.,..,..•......... >.., ti 3.f : D13026-1: PDC PC5 PROFILE COMP 1 7 3.'2: D 13026 -2: PDC PC5 PROFILE COMP 2 11 3,3: D13026 -3: PDC PC5 PROFILE COMP 3 15 3. : D13026 -4: PDC GG2 PROFILE COMP 1 19 3.S: D13026 -5: PDC GG2 PROFILE COMP 2 23 3,6: D13026 -6: PDC GG2 PROFILE COMP 3 27 Section 4: Misc. Forms ,.. 31 4.1: Chain of Custody 32 Section 5: GC Volatiiles QC Data Suinniaries 33 5.1: Method Blank Summary 34 5.2: Blank Spike Summary 37 5.3: Matrix Spike /Matrix. Spike Duplicate Summary 40 Section 6: GC Semi- vol.atiles - QC Data Summaries 43 6.1: Method Blank Summary 44 6.2: Blank Spike Summary ..... 45 6.3: Matrix Spike/Matrix Spike Duplicate Summary 46 Section 7: General Chemistry - QC Data Summaries 47 7.1: Method Blank and Spike Results Summary 48 Sections: On 2 of 48 taACCUTEST. 013020 I =4 r,., i•s,,.. Accutest Laboratories Sample Summary PDC PDC -PC5 & GG2 Profile Sampling Job No: D13026 Sample Collected Matrix Client Number Date Time By Received Code Type Sample Ii} D13026 -I 05/04/10 13:20 HL 05/05/10 SO Soil D13026 -2 05/04/10 13:25 HL 05/05/10 SO Soil D13026 -3 05/04/10 13:50 HL 05/05/10 SO Soil D13026 -4 95/04/10 14 :20 HL 05/05/10 SO Soil D13026 -5 05/04/10 14 :30 HL 05/05/10 SO Soil D13026-6 05/04/10 14:45 HL 05/05/10 SO Soil PDC PC5 PROFILE COMP 1 PDC PC5 PROFILE COMP 2 PDC PC5 PROFILE COMP 3 PDC GG2 PROFILE COMP 1 PDC GG2 PROFILE COMP 2 PDC GG2 PROFILE COMP 3 Soil samples reported on a dry weight basis unless otherwise indicated on result page. ON 3 of 48 ACCUTEST 013026 1 ..� /4CCUTEST: Laboratories CASE NARRATIVE / CONFORMANCE SUMMARY Client: PDC Site: PDC -PC5 & GG2 Profile Sampling 1:1 Job No D13026 Report Dat 5/12/2010 5 :01 :21 PM On 05/05/2010, six (6) samples were received at Accutest Mountain States at atemperature of3.0°C. The samples were intact and properly preserved, unless noted below. An Accutest Mountain States Job Number of D13026 was assigned to the project. The laboratory sample IDs, client sample IDs, and dates of sample collection are detailed in the report's Results Summary Specified quality control criteria were achieved for this job except as noted below, For more information, please refer to the analytical results and QC summary pages, Volatiles by GC By Method SW846 8015B Matrix SO Batch ID: GGB231 ▪ All samples were analyzed within the recommended method holding time. • Samples D13026 -IMS and D13026 -1MS1] were used as the QC samples indicated. • All method blanks for this batch meet method specific criteria. • Samples D13026 -1MS, D13026 -1MSD, D13026 -2, D13026 -3, D13026 -5, and D13026-6 have the surrogate outside control limits due to coeluting interference. This does not affect the analysis of the target analytes, which elute before the interference. Volatiles by GC By Method SW846 8021B Matrix SO Batch ID: GTB231 ® All samples were analyzed within the recommended method holding time, ® Samples D13026 -1M5 and D13026 -1MSD were used as the QC samples indicated. M All method blanks for this batch meet method specific criteria, Matrix SO Batch ID: GTB234 • All samples were analyzed within the recommended method holding time. ® Samples D12636 -20MS and D12636 -20MSD were used as the QC samples indicated, • All method blanks for this batch meet method specific criteria. Extractables by GC By Method SW846 -8015B Matrix SO Batch ID: OP1823 61 All samples were extracted within the recommended method holding time. al All samples were analyzed within the recommended method holding time. ra Samples DI3026 -1MS and D13026 -1MSD were used as the QC samples indicated, All method blanks for this batch meet method specific criteria. Wet Chemistry By Method SM 19 2540B M Matrix SO Batch ID: GN4225 The data for SM19 2540E M meets quality control requirements. Wednesday, May 12, 2010 Page 1 of2 4 of 48 tjACCUTEST. 013026 i,�:�" •, ,•:> Wet Chemistry By Method SW846 1010, PM CC Matrix ALL Batch ID: GN4224 • The data for SW846 1010, PM CC meets quality control requirements, ® Samples D13026-1 through -4 Flashpoint At 620 mm Hg: Not ignitable. Matrix ALL Batch ID: GN4251 G, Samples D13026 -5 and D13026 -6 for Flashpoint At 620 min Hg: Ignitable Wet Chemistry By Method SW846 7.2 Matrix So Batch ID: GN4234 • Conrosivity as pi I: Non Corrosive for all samples. Wet Chemistry By Method SW846 9095 Matrix so Batch ID: GN4226 • The data for SW846 9095 meets quality control requirements. Paint Filter Test: No free liquids for all samples. Wet Chemistry By Method SW846 CHAP 7.3 Matrix SO Batch ID: GP1904 All samples were prepared within the recommended method holding time. • All samples were analyzed within the recommended method bolding lime. • All method blanks for this batch meet method specific criteria. Wet Chemistry By Method SW846 CHAP7 Matrix SO Batch ID: GP1907 • All samples were prepared within the recommended method holding time. • All samples were analyzed within the recommended method holding time. • All method blanks for this batch meet method specific criteria, Accutest Mountain States certifies that data reported for samples received, listed on the associated custody chain or analytical task order, were produced to specifications meeting Accutest Mountain States's Quality System precision, accuracy and complete Estimated non-standard method measurement uncertainty data is available on request, based on quality control bias and implicit for standard methods. Acceptable uncertainty requires tested parameter quality control data to meet method criteria. Accutest Mountain States is not responsible for data quality assumptions if partial reports are used and recommends that this report be used in its entirety. Data release is authorized by Accutest Mountain States indicated via signature on the report cov Wednesday, May 12, 2010 Page 2 oft ffil® 5of48 ®ACCU7ESt n13026 i:,L ^ *- > =.:> Eari Mountain States ACCUTEST - L bol a , it'S ALL IN itit cuemisiltY Sample Results Report of Analysis S 1 io, EIN 6 of 48 gjACCIJTESI: 013028 L Le r.11o111 Accutest Laboratories Report of Analysis Page 1 of I Client Sample ID: Lab Sample ID: Matrix: Method: Project: PDC PC5 PROFILE COMP 1 D 13026 -1 SO - soil SW846 8015B PAC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 79.3 Run #1 Run #2 File ID GB4271.D DF 1 Analyzed By 05/07/10 DG Prep Date n/a Prep Batch Analytical Batch n/a GGB231 Run #1 Run #2 Initial Weight Final Volume Methanol Aliquot 5.O g 10.0 ml 25.0 ul CAS No. CAS No. 120 -82 -1 Compound TPH -GRO (C6 -C10) Surrogate Recoveries 1,2,4 - Trichlorobenzene Result RL MDL Units 2870 110 110 mg/kg Run# 1 Run# 2 Limits 140% 60 -140% Q ND = Not detected MDL - Method Detection Limit RL = Reporting Limit E = Indicates value exceeds calibration range I= Indicates an estimated value B = Indicates analyze found in associated method blank N = Indicates presumptive evidence of a compound f® 7of48 AccUTEet D13026 Lea ,s Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: Lab Sample ID: Matrix: Method: Project: PDC PC5 PROFILE COMP 1 D13026-1 SO - Soil SW 846 802113 PDC -PC5 & G02 Profile Sampling Date Sampled: 05/04/10 Date Received: 05 /05 /10 Percent Solids: 79.3 Run #1 Run #2 File ID TB4271.D DF Analyzed By 05/07/10 DG Prep Date n/a Prep Batch Analytical Batch n/a GTB231 Run #1 Run #2 Initial Weight Final Volume Methanol Aliquot 5.0 g 10.0 ml 25.0 ul Purgeable Aromatics CAS No. Compound Result RL 71 -43 -2 Benzene 1230 560 108 -88 -3 Toluene 17900 1100 100 -41 -4 Ethylbenzene 12900 1I00 m,p-Xylene 131000 1100 95 -47 -6 o- Xylene 16900 1100 CAS No, Surrogate Recoveries Run# 1 Run# 2 120 -82 -1 1,2,4 - Trichlorobenzene 106% MDL Units Q 560 1100 1100 1100 1100 ug/kg ug/kg ug/kg ug/kg ug/kg Limits 60 -140% ND = Not detected MDL - Method Detection Limit RL = Reporting Limit E = Indicates value exceeds calibration range J — Indicates an estimated value B = Indicates analyte found in associated method blank N = Indicates presumptive evidence of a compound O© 8 of 48 gACCI~ F EST. D13026 I - 4 .> Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: PDC PC5 PROFILE COMP 1 Lab Sample ID: D13026 -1 Matrix: Method: Project: SO - Soil SW846 -8015B SW846 3550B PDC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received; 05/05/10 Percent Solids: 79.3 Run #1 Run #2 File ID FD 1225. D DF 1 Analyzed By 05/07/10 CP Prep Date 05/07/10 Prep Batch Analytical Batch OP 1823 GFD88 Run #1 Run #2 Initial Weight Final Volume 30.1 g 2.0 ml CAS No. Compound TPH -DRO (C10 -C28) CAS No. Surrogate Recoveries 84 -15 -1 o- Terphenyl Result RL Units Q 257 17 mg/kg Run# 1 Run# 2 Limits 85% 63 -130% ND = Not detected RL = Reporting Limit E = Indicates value exceeds calibration range 7 = Indicates an estimated value B = Indicates analyte found in associated method blank N Indicates presumptive evidence of a compound WI 9 of 48 El.AGGL.9TEBT 013026 L,� :•.i„ vs Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: PDC PC5 PROFILE COMP i Lab Sample ID: D13026 -I Matrix: SO - Soil Project: PDC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05 /05 /10 Percent Solids: 79.3 General Chemistry Analyte Corrosivity as pH a Cyanide Reactivity Flasltpoint At 620 mm Hg b Paint Filter Test Solids, Percent Sulfide Reactivity (a) Non Corrosive (b) Not ignitable (o) No free liquids. Result RI_, Units Dr Analyzed By Method 8.87 su I 05/05/10 12:35 JK < 1.5 1.5 mg /kg 1 05/07/10 m > 140 Deg. F 1 05/05/10 JJ < 1.0 1.0 ml/ 100g 1 05/05/10 JJ 79.3 % 1 05/05/10 SWT 90.0 10 mg /kg 1 05/07/10 JD SW846 7.2 SW846 CHAP7 SW846 1010, PM CC SW846 9095 SM19 25408 M SW846 CHAP 7.3 RL = Reporting Limit sin 10 of 48 ACCUTEST D13026 Lsz..:•�•��u�,.. Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: PDC PC5 PROFILE COMP 2 Lab Sample ID: D13026 -2 Matrix: Method: Project: SO - Soil SW846 801513 PDC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 83.0 Run #1 Run #2 File ID GB4285.D DF 1 Analyzed By 05/07/10 DG Prep Date n/a Prep Batch Analytical Batch n/a GGB231 Run 41 Run #2 Initial Weight Final Volume Methanol Aliquot 5.0 g 10.0 nil 100 ul CAS No. Compound Result RL MDL Units TPH -GRO (C6 -C10) 1780 26 26 mg/kg CAS No. Surrogate Recoveries Run# 1 Run# 2 Limits 120 -82 -1 1,2,4 -- Triohlorobenzene 193% a 60 -140% (a) Outside control limits due to matrix interference. Q ND = Not detected MDL - Method Detection Limit RL — Reporting Limit E = Indicates value exceeds calibration range J = Indicates an estimated value B — Indicates analyte found in associated method blank N = Indicates presumptive evidence of a compound © 11of48 gl ACCIUTEST. 013026 L t,.:, Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: Lab Sample ID: Matrix: Method: Project: PDC PC5 PROFILE COMP 2 D13026-2 SO - Soil SW846 8021B PDC -PC5 & 0G2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 83.0 Run #1 Run #2 File ID TB4285,D TB4274.D DF 1 1 Analyzed 05/07/10 05/07/10 By DG DG Prep Date n/a n/a Prep Batch n/a n/a Analytical Batch GTB231 GT8231 Run #1 Run #2 Initial Weight 5.0 g 5.0 g Final Volume 10.0 ml 10.0 ml Methanol Aliquot 100 ul 40.0 ul Purgeable Aromatics CAS No. Compound 71 -43 -2 Benzene 108 -88 -3 Toluene 100 -41 -4 Ethylbenzene rn,p- Xylene 95 -47 -6 o- Xylene CAS No. Surrogate Recoveries 120 -82 -1 1,2,4 - Trichlorobenzene (a) Result is from Run# 2 Result RL MDL Units 394 130 130 2790 260 260 7720 260 260 84300 a 650 650 7490 260 260 ug /kg ug /kg ug /kg ug /kg ug /kg Run# I Run# 2 Limits 140% 105% 60 -140% Q ND = Not detected MDL - Method Detection Limit RL = Reporting Limit E = Indicates value exceeds calibration range J = Indicates an estimated value 13 = Indicates analyte found in associated method blank N = Indicates presumptive evidence of a compound fain 12 of 48 ®ACCUTEST. 013026 l b Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: PDC PC5 PROFILE COMP 2 Lab Sample ID: D13026 -2 Matrix: Method: Project: SO - Soil SW846 -8015B SW846 3550E PDC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 83.0 Run #1 Run #2 File ID FD 1228. D DF 1 Analyzed By 05/07/10 CP Prep Date 05/07/10 Prep Batch Analytical Batch OP 1823 GFD88 Run #1 Run #2 Initial Weight Final Volume 30.1 g 2.0 ml CAS No. Compound TPH -DRO (C10-C28) CAS No. Surrogate Recoveries 84 -15 -1 o- Terphenyl Result RL Units Q 165 16 mg/kg Run# 1 Run# 2 Limits 90% 63 -130% ND = Not detected RL = Reporting Limit E = Indicates value exceeds ealibration range J = Indicates an estimated value B = Indicates analyte found in associated method blank N = Indicates presumptive evidence of a compound M® 13 of 48 13 ACC UTEST D13026 Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: PDC PC5 PROFILE COMP 2 Lab Sample ID: D13026 -2 Matrix: SO - Soil Project: PDC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 83.0 General Chemistry Analyte Corrosivity as pH a Cyanide Reactivity Flashpoint At 620 mm Hg b Paint Filter 'Pest Solids, Percent Sulfide Reactivity (a) Non Corrosive (b) Not ignitable (c) No free liquids. Result RL Units DF Analyzed By Method 8.73 al 1 05/05/10 12:35 JK < 1.5 1.5 mg /kg I 05/07/10 JD > 140 Deg. F 1 05/05/10 JJ < 1.0 1.0 m1/100g 1 05/05/10 JJ 83 % 1 05/05/10 SW'r 10.0 10 mg/kg 1 05/07/10 JD SW846 7.2 SW846 CHAP7 SW846 1010, PM CC SW846 9095 SM19 2540B M SW846 CHAP 7.3 RL — Reporting Limit El 14 of 48 ggi ACC I<JTEST. 013026 � � Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: Lab Sample ID: Matrix: Method: Project: PDC PC5 PROFILE COMP 3 D13026-3 SO - Soil SW846 8015B PDC -PC5 & 002 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 83.5 Run #1 Run #2 File ID O134275.D DF 1 Analyzed By 05107/10 DG Prep Date n/a Prep Batch Analytical Batch n/a 0013231 Run #1 Run #2 Initial Weight Final Volume Methanol Aliquot 5.O g 10.0 ml 40.0 ul CAS No. Compound TPH -GRO (C6 -C10) CAS No. Surrogate Recoveries 120 -82 -1 I,2,4- Trichlorobenzene Result RL MDL Units 2230 65 Run# 1 Run# 2 184% (a) Outside control limits due to matrix interference. 65 mg/kg Limits 60 -140% Q ND = Not detected MDL - Method Detection Limit RL = Reporting Limit E = Indicates value exceeds calibration range J = Indicates an estimated value 13 = Indicates analyte found in associated method blank N = Indicates presumptive evidence of a compound <r; Ed 15 of 48 EjACCUTEST. 013026 Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: Lab Sample ID: Matrix: Method: Project: PDC PC5 PROFILE COMP 3 D 13026 -3 SO - Soil SW846 8021E PDC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 83.5 Run #1 Run #2 File ID T134275. D DF 1 Analyzed By 05/07/10 DG Prep Date n/a Prep Batch Analytical Batch n/a GTB231 Run #1 Run #2 Initial Weight Final Volume 5.0 g 10.0 ml Methanol Aliquot 40.0 ul Purgeable Aromatics CAS No, Compound 71 -43 -2 Benzene 108 -88 -3 Toluene 100 -41-4 Ethylbenzene m,p- Xylene 95 -47 -6 o- Xylene CAS No. Surrogate Recoveries Result RL MDL Units Q 398 320 320 ug/kg 14600 650 650 ug /kg 4830 650 650 ug/kg 72700 650 650 ug/kg 16500 650 650 ug /kg Run# 1 Run# 2 Limits 120 -82 -1 1,2,4- Trichiorobenzene 120% 60-140% ND = Not detected MDL - Method Detection Limit RL = Reporting Limit E = Indicates value exceeds calibration range J = Indicates an estimated value B = Indicates analyle found in associated method blank N = Indicates presumptive evidence of a compound ® 16of4B ACCLrrEST 1:113628 I,,:: Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: Lab Sample ID: Matrix: Method: Project: PDC PC5 PROFILE COMP 3 D13026-3 SO - Soil SW846 -801513 SW846 35503 PDC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 83.5 Run #1 Run #2 File ID FD 1229. D DF Analyzed By 05/07/10 CP Prep Date 05/07/10 Prep Batch Analytical Batch OP1823 GFD88 Run #1 Run #2 Initial Weight Final Volume 30.2 g 2,0 ml CAS No. CAS No. 84 -15 -1 Compound TPH -DRO (C10-C28) Surrogate Recoveries o- Terphenyl Result 332 Run## 1 84% RL Units Q 16 mg/kg Run# 2 Limits 63 -130% ND = Not detected RL = Reporting Limit E = Indicates value exceeds calibration range J = Indicates an estimated value B = Indicates analyte found in associated method blank N = Indicates presumptive evidence of a compound u© 17 of 48 ACCUTEST. 013026 L ,.�aio„•:. Aceutest Laboratories Report of Analysis Page 1 of 1 Client Sample 1D: PDC PC5 PROFILE COMP 3 Lab Sample ID: D13026 -3 Matrix: SO - Soil Project: PDC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 83.5 General Chemistry Analyte Corrosivity as pH a Cyanide Reactivity Flashpoint At 620 mm Hg b Paint Filter `test c Solids, Percent Sulfide Reactivity (a) Non Corrosive (h) Not ignitable (c) No free liquids. Result 9.20 < 1.5 > 140 < 1.0 83.5 20.0 RL Units DF Analyzed By su 1 1.5 mg /kg 1 Deg, F 1 1.0 m1/100g 1 10 mg /kg 1 05/05/10 12:35 33( 05/07/10 .m 05/05/10 ra 05/05/10 1] 05/05/10 05/07/10 SWT rD Method SW846 7.2 SW846 CHAP? SW846 1010, PM CC SW846 9095 SM19 254013 M SW846 CHAP 7.3 RL = Reporting Limit QQ 18 of 48 CIACCLJTEST. 013026 t ,.<to�,.., Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: PDC 002 PROFILE COMP 1 Lab Sample ID: D13026 -4 Matrix: Method: Project: SO - Soil SW846 8015B PDC -PCS & 002 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 81.2 Run #1 Run. #2 File ID GB4276,D DF Analyzed By 05/07/10 DO Prep Date n/a Prep Batch Analytical Batch n/a 00B231 Initial Weight Final Volume Methanol Aliquot Run #1 5.0 g 10,0 ml 10,0 ul Run #2 CAS No. Compound Result RL MDL Units TPH -GRO (C6 -C10) 6830 270 270 mg/kg CAS No. Surrogate Recoveries Run# 1 Run# 2 Limits 120 -82 -1 1,2,4 - Trichlorobenzene 131% 60 -140% Q ND = Not detected MDL - Method Detection Limit RL = Reporting Limit E = Indicates value exceeds calibration range ,T= Indicates an estimated value 13 = Indicates analyte found in associated method blank N = Indicates presumptive evidence of a compound E® 19 of 48 ® ACCUTEST. 013026 L��..•�•�i•a�,.� Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: PDC GG2 PR ©FILE COMP Lab Sample ID: D13026 -4 Matrix: Method: Project: SO - Soil SW846 8021E PDC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 8L2 Run #1 Run #2 File ID TB4276.D DF 1 Analyzed By 05/07/10 DO Prep Date n/a Prep Batch Analytical Batch n/a GTB231 Run #1 Run #2 Initial Weight Final Volume Methanol Aliquot 5.0g 10.0 ml 10.Oul Purgeable Aromatics CAS No. Compound Result RL MDL Units Q 71 -43 -2 Benzene 7920 1300 1300 ug/kg 108 -88 -3 Toluene 125000 2700 2700 ug /kg 100 -41 -4 Ethythenzene 27500 2700 2700 ug/kg m,p- Xylene 239000 2700 2700 ug/kg 95 -47 -6 o- Xylene 52200 2700 2700 ug/kg CAS No, Surrogate Recoveries Run# 1 Run# 2 Limits 120 -82 -1 1,2,4 - Trichlorobenzene 104% 60 -140% ND — Not detected MDL - Method Detection Limit RL m Reporting Limit E = Indicates value exceeds calibration range J = Indicates an estimated value B = Indicates analyte found in associated method blank N = Indicates presumptive evidence of a compound c3 EBEI 20 of 48 giACCLITES1 D13026 r°.� Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: PDC GG2 PROFILE COMP 1 Lab Sample ID: D13026 -4 Matrix: Method: Project: SO - Soil SW846 -8015B SW896 3550E PDC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 8L2 Run #1 Run #2 File 11) FD 1255.D DF Analyzed By 10 05 /10 /10 CP Prep Date 05/07/10 Prep Batch Analytical Batch OP1823 GFD89 Run #1 Run #2 Initial Weight Final Volume 30.1 g 2.Oml CAS No. Compound TPH -DRO (C10-C28) CAS No. Surrogate Recoveries 84 -15 -1 o- Terphenyl Result RL Units Q 4690 160 mg /kg Run# 1 Run# 2 Limits 127% 63 -130% ND = Not detected RL = Reporting Limit E = Indicatcs value exceeds calibration range .1= Indicates an estimated value B = Indicates analyte found in associated method blank N = Indicates presumptive evidence of a compound t d 21 of 48 ACCL TEST. D13928 Accutest Laboratories Report of Analysis Page I of I Client Sample ID: PDC GG2 PROFILE COMP 1 Lab Sample ID: D13026 -4 Matrix: SO - Soil Project: PDC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 81.2 General Chemistry Analyte Corrosivity as pH a Cyanide Reactivity Flashpoint At 620 mm Hg b Paint Filter Test ° Solids, Percent Sulfide Reactivity (a) Non Corrosive (b) Ignitable (c) No free liquids. Result RL Units DI? Analyzed By Method 9.43 su 1 05/05/10 12:35 JK < 1.5 1.5 mg/kg 1 05/07/10 JD 65.0 Deg. F 1 05/06/10 JJ < 1.0 1.0 ml/100g 1 05/06/10 JJ 81.2 % 1 05/05/10 SWT < 10 10 mg /kg I 05/07/10 JD SW846 7.2 SW846 CHAP? SW846 1010, PM CC SW846 9095 SM 19 25408 M SW846 CHAP 7.3 RL = Reporting Limit 22 of 48 ®A.CCUTEST. 013026 +...� .� , Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: Lab Sample ID: Matrix: Method: Project: PDC GG2 PROFILE COMP 2 D13026-5 SO - Soil SW846 8015B PDC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 82.8 Run #1 Run #2 File ID GB4277.D DF 1 Analyzed By 05/07/10 DG Prep Date n/a Prep Batch Analytical Batch n/a GGB231 Run #1 Run #2 Initial Weight Final Volume Methanol Aliquot 5.Og 10,0 ml 40,Oul CAS No. CAS No. 120 -82 -1 Compound TPH -0rR0 (C6 -C10) Surrogate Recoveries 1,2,4- Trichlorobenzene Result 2720 Run# 1 161% a (a) Outside control limits due to matrix interference. RL MDL Units 66 66 mg/kg Run# 2 Limits 60 -140% Q ND = Not detected MDL - Method Detection Limit RL = Reporting Limit E = Indicates value exceeds calibration range J = Indicates an estimated value B = Indicates analyte found in associated method blank N = Indicates presumptive evidence of a compound M© 23 of 48 CACCL.UTES , 013026 L l. " u l v i •: s Aceutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: Lab Sample ID: Matrix: Method: Project: PDC GG2 PROFILE COMP 2 D13026-5 SO - Soil SW846 8021B PDC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 82.8 Run #1 Run #2 File ID TB4350.D DF l Analyzed By 05/11/10 DG Prep Date n/a Prep Batch Analytical Batch n/a GTB234 Run #1 Run #2 Initial Weight Final Volume 5.0 g 10.0 ml Methanol Aliquot 25.0 ul Purgeable Aromatics CAS No. Compound 71 -43 -2 Benzene 108 -88 -3 Toluene 100 -41 -4 Ethylbenzene m,p- Xylene 95 -47 -6 a- Xylene CAS No. Surrogate Recoveries 120 -82 -1 1,2,4 - Trichlorobenzene Result RL MDL Units Q 1320 520 520 ug/kg 47200 1000 1000 ug /kg 11000 1000 1000 ug/kg 141000 1000 1000 ug/kg 29500 1000 1000 ug/kg Rung 1 Run# 2 Limits 102% 60 -140% ND = Not detected MDL - Method Detection Limit RL = Reporting Limit E = Indicates value exceeds calibration range I Indicates an estimated value B = Indicates analyte found in associated method blank N = indicates presumptive evidence of a compound © 24 of 48 glACCUTEST. U13Ll26 i,L.c i -a� .. Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: PDC GG2 PROFILE COMP 2 Lab Sample ID: D13026 -5 Matrix: Method: Project; SO - Soil SW846- 801513 SW846 3550B PDC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05! 10 Percent Solids: 82.8 Run #1 Run #2 File ID FD 1231.D DF 1 Analyzed By 05/07/10 CP Prep Date Prep Batch Analytical Batch 05/07/10 OP1823 GFD88 Run #1 Run #2 Initial Weight Final Volume 30.2g 2.O m1 CAS No. Compound TPH -DRO (C10-C28) CAS No. Surrogate Recoveries 84 -15 -1 o- Terphenyl Result RL Units Q 994 16 mg/kg Run# 1 Run# 2 Limits 97% 63- 130% ND = Not detected RL = Reporting Limit E = Indicates value exceeds calibration range = Indicates an estimated value B = Indicates analyte found in associated method blank N = Indicates presumptive evidence of a compound cfi ® 25 of 48 ACCUTEST. D13426 4,a•, „,,,' Accutest Laboratories Report of Analysis Page 1 of' 1 Client Sample ID: PDC GG2 PROFILE COMP 2 Lab Sample ID: D13026-5 Matrix: SO - Soil Project: PDC -PC5 & 002 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 82.8 General Chemistry Analyte Corrosivity as pH a Cyanide Reactivity Flashpoint At 620 mm Hg 1r Paint Filter Test Solids, Percent Sulfide Reactivity (a) Non Corrosive (b) Ignitable (c) No free liquids, Result RL Units DF Analyzed By Method 9.28 su 1 05/05/10 12;35 JK < 1.5 1.5 mg/kg 1 05/07/10 JD 110 Deg. F 1 05/06/10 JJ < 1,0 1.0 m1/100g 1 05/06/10 JJ 82.8 % 1 05/05/I0 SWT < 10 10 mg/kg 1 05/07/I0 JD SW846 7.2 SW846 CHAP7 SW846 1010, PM CC SW846 9095 SM 19 2540E M SW846 CRAP 7.3 RL = Reporting Limit © 26 of 48 CIA St 1313026 I .,G•.�,,,: Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: Lab Sample ID: Matrix: Method: Project: PDC GG2 PROFILE COMP 3 D 13026 -6 SO - Soil SW846 8015B PDC -PCS & G02 Profile Sampling Date Sampled: 05/04/10 Date Received: 05 /05 /10 Percent Solids: 84.0 Run #1 Run #2 File ID GB4278,D DF 1 Analyzed By 05/07/10 DG Prep Date n/a Prep Batch Analytical Batch n/a GGB231 Run #1 Run #2 Initial Weight Final Volume 5.0 g 10.0 ml Methanol Aliquot 100 ul CAS No. Compound TPH -GRO (C6-C10) CAS No. Surrogate Recoveries 120 --82 1 1,Z 4- Trichlorobenzene Result RL MDL Units 814 26 Run# 1 Run# 2 151% a (a) Outside control limits due to matrix interference. 26 mg/kg Limits 60-140% Q ND = Not detected MDL - Method Detection Limit RL .— Reporting Limit E Indicates value exceeds calibration range J = Indicates an estimated value B = Indicates analyte found in associated method blank N = Indicates presumptive evidence of a compound G® 27 of 48 ACCUTEST. D13026 L4L' ;o _.> • Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: Lab Sample ID: Matrix: Method: Project: PDC GG2 PROFILE COMP 3 D13026-6 SO _ Soil SW846 8021B PDC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 84.0 Run #1 Run #2 File ID TB4278.D DF 1 Analyzed By 05/07/10 DG Prep Date n/a Prep Batch Analytical Batch n/a GTB231 Run #1 Run #2 Initial Weight Final Volume 5.0 g 10.0 ml Methanol Aliquot 100 ul Purgeable Aromatics CAS No. Compound 71 -43 -2 Benzene 108 -88 -3 Toluene 100-41 -4 Ethylbenzene m,p- Xylene 95 -47 -6 o- Xylene CAS No. Surrogate Recoveries Result RL MDL Units Q 184 • 130 130 ug/kg 998 260 260 ug/kg 2810 260 260 ug/kg 33200 260 260 ug /kg 5110 260 260 ug/kg Run# 1 Run# 2 Limits 120 -82 -1 1,2,4- Trichlorobenzene 114% 60- 140% ND = Not detected MDL - Method Detection Limit RL = Reporting Limit E — Indicates value exceeds calibration range .1= Indicates an estimated value B Indicates analyte found in associated method blank N = Indicates presumptive evidence of a compound © 28 of 48 tjACCUT'EST 013026 i ic> Aceutest Laboratories Report of Analysis Page 1 of' 1 Client Sample ID: PDC GG2 PROFILE COMP 3 Lab Sample ID: D13026-6 Matrix: Method: Project: SO - Soil SW846 -80158 SW846 3550E PDC -PC5 & GG2 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 84.0 Run #1 Run #2 File ID FD 1232. D DF 1 Analyzed By 05/07/10 CP Prep Date 05/07/10 Prep Batch Analytical Batch 01'1823 GFD88 Run #1 Run #2 Initial Weight Final Volume 30.1 g 2.0 ml CAS No. Compound TPH -DRO (C10 -C28) CAS No. Surrogate Recoveries 84 -15 -1 o- Terphenyl Result RI.. Units Q 1040 16 mg/kg Run# 1 Run# 2 Limits 88% 63 -130% ND = Not detected RL = Reporting Limit E = Indicates value exceeds calibration range J = Indicates an estimated value B = Indicates analyte found in associated method blank N = Indicates presumptive evidence of a compound E© 29 of 48 glAccLrIEST. 013025 1- . .. I Accutest Laboratories Report of Analysis Page 1 of 1 Client Sample ID: PDC GG2 PROFILE COMP 3 Lab Sample ID: D13026-6 Matrix: SO - Soil Project: PDC -PC5 & 002 Profile Sampling Date Sampled: 05/04/10 Date Received: 05/05/10 Percent Solids: 84.0 General Chemistry Analyte Corrosivity as pH a Cyanide Reactivity Flashpoint At 620 mm Hg b Paint Filter Test Solids, Percent Sulfide Reactivity (a) Non Corrosive (b) Ignitable (c) No free liquids. Result RL Units DF Analyzed By Method 9.30 su 1 05/05/10 12:35 nc < 1.5 1.5 mg/kg 1 05/07/10 ro 95.0 Deg, F 1 05/06/10 JJ < 1.0 1.0 m1/100g 1 05/06/10 JJ 84 % 1 05/05/10 SWT < 10 10 mg/kg 1 05/07/10 JrD SW846 7.2 SW846 CHAP7 SW846 1010, PM CC SW846 9095 SM 19 2540B M SW846 CHAP 7.3 RL = Reporting Limit ra® 30 of 48 ACCUTESY' D13026 L,a., i,��.:> nMountain States ACCUTEST L b ou z L c.11 c s II'S ALI. IN Hit CilfritSIAV Misc. Forms A Custody Documents and Other Forms Includes the following where applicable: • Chain of Custody Section 4 M1 31 of 48 4AccUTEst 013026. •■ 5 siAC▪ Ciu s-r. Cdhnli Reporting lnrormair CHAIN OF CUSTODY 4036 Ynun3riela Seem, Wheat Ridge, Colorado 30033 TEL 303.4216071; 377 -737 -0521 FAX 303.425-6454 p FraY.tr1>nl: cL reformaihn Fell TrrJh+l PAGE OF Cn'.rOnnm• 1 �:c�1:�E r lirj=:Ij'.lfr -... . - •misled Ana .Ix a es TEST 606E aha6lj ' �l �' ,. ., '1�G -,CGS (G:IA: rC /; y l,cat �� MY- 0m33,ow.rrr ` iv Fs fi :.. CL :?-P? tLW- Oaa.nawa.r �/1 tiptT- 3T1��f12 lenCVmm..ml.nnw4awl ww -waa cav D4 su. sw- o-�smvrn Gi+++�l� .27 k . 6 s auayl PanjLMCataai E..,U aq.ar seas want d%8fn7ea, Lv o. / [akin' J4'ko+ r<e,M �ti� /rrrov�. v STG-17 1 ° � a�a 4 O nl Purlrue0n MY 6444 / ufl u �7a'1 3 ,3.z7 .2y3 jr�ci'O 5 sOL. Clhtt.e4a S..d1d14 nameyl J424: P. wv -wP. Plbne 1 P,40.1.wyM 'geiNyR /5 s F &Fleba4nk sYG ���' //er„Ta a Gvrx/r7 em ,4: /P// ,(4' e F 3 'Axe MOW 10 /Point d Cakocplon aaaama..,, T.. .a.e11 / elbstu mop Lae Use 0HLT ■■ F = -. �-�f�■.i! ■ ■■■■■ e �IMMI■■■ ` _ .'.■.■.■■. ■CG®....... �� �I'ESCI■ ■■■ ■ ■t■e�111.11111111111•1 w. O IN IIE iMI �� �■■1:■�■■■■■■ ■—_■ 1. A������MI■i■■■■■■ ___ IN • 7 �����■■■■■■■ ■� INRU.� MIIIIMMINimiaM �����■ ■■■■■■■�M....M ill :■ :■■■■■■■r'. •1 :�. �IIi111■■■■■11■■ ■A..111N11•1111a Mehra Codes [� eld to ea Jnl o.y■ ❑ UBTM.1yd.36 oars ▪ iloocOVAO 3 •S Oar miss ❑ au.Y &assessor ❑ Ibp} EMERGENCY Pura T!A by .valabl. YH !WOE L f an'ri ?- I Nrvavaeey14a1a IPI4fl4.IM 4e6.1 MI L47.12 L.r.l Lvrvl4 iaF1l I - flu.as ON LW442. Math.I CC Coo.00Iy ♦ w. 6.n»W6 Lorda.ee.u4. CO Svavery, P.i141 P.m data LCC44 —IM OO600Oa Coe • moo l to eacaan .nled below goal, Hole .am ssosalerl. 1061404 Maio YbF EDO Few..l OJr.a Comments! .clotfrolrud]aaa f es6. ray ,o 7a -may 17,-, rev/ s75 r rrc,E T`54-fr441s - (3414.4 0 eci - 4141 3 n...a.wley; ,, .1 1 II .. r61J 3 3 M4pe•a1p 01.1 Thml Ilneadl; i t ■41111 tiai Y knetnO 61CYwtl.an W p M11wnrd'+Mn D13026: Chain of Custody Page 1 of 1 ®® 32 of 48 ®ACCL fl EST. D13026 L1t+ol,.I,pl r.a inMountain States �ACCUTEST L e 1 0 1 t, Nok 0 i I'S ALL [hf i kt CHE 11151 iY GC Volatiles QC Data Summaries Includes the following where applicable: • Method Blank Summaries • Blank Spike Summaries • Matrix Spike and Duplicate Summaries Method Blank Summary Job Number: 013026 Account: PDCCOP PDC Project: PDC -PC5 & GG2 Profile Sampling Page 1 of 1 Sample File ID DF Analyzed By Prep Date Prep Batch Analytical Batch 008231 -MB G84269.D 1 05/07/10 DG ula n/a GGB231 The QC reported here applies to the following samples: D 13026 -1, D 13026 -2, 013026-3, 013026 -4, D 13026 -5, D 13026 -6 Method: SW846 8015E CAS No. Compound Result RL MDL Units Q TPH -GRO (C6-C10) ND 20 20 mg/kg CAS No. Surrogate Recoveries Limits 120 -82 -1 1,2,4 - Trichlorobenzene 88% 60 -140% ® 34 of 48 ® ACC UTESt D13526 -.'U:'roI91 , Method Blank Summary Job Number; D13026 Account: PDCCOP PDC Project: PDC -PC5 & GG2 Profile Sampling Page 1 of 1 Sample File 11) DF Analyzed By Prep Date Prep Batch Analytical Batch GT13231 -MB TB4269.D 1 05/07/10 DO n/a n/a GTB231 The QC reported here applies to the following samples: D13026 -1, D13026 -2, DI3026 -3, D13026 -4, D13026 -6 Method: SW846 8021B CAS No. Compound Result RL MDT, Units Q 71 -43 -2 Benzene ND 100 100 ug /kg 100 -41-4 Ethylbenzene ND 200 200 ug/kg 108 -88 -3 Toluene ND 200 200 ug /kg 95 -47 -6 o- Xylene ND 200 200 ug /kg m,p- Xylene ND 200 200 ug/kg CAS No. Surrogate Recoveries Limits 120 -82 -1 1,2,4- Trichlorobenzene 84% 60- 140% En 35 of 48 ACGUTEST D13026 L ;,,.:, Method Blank Summary Job Number: D13026 Account: PDCCOP PDC Project: PDC -PC5 & GG2 Profile Sampling Page 1 of 1 Sample File ID DF Analyzed By Prep Date Prep Batch Analytical Batch GTB234 -MB TB4345.D 1 05/11/10 DO n/a n/a 0TB234 The QC reported here applies to the following samples: D13026-5 Method: SW846 8021B CAS No. Compound Result RL MDL Units Q 71 -43 -2 Benzene ND 100 100 ug/kg 100 -41 -4 Ethylbenzene ND 200 200 ug/kg 108 -88 -3 Toluene ND 200 200 ug /kg 95 -47 -6 o- Xylene ND 200 200 ug /kg m,p- Xylene ND 200 200 ug/kg CAS No. Surrogate Recoveries Limits 120 -82 -1 1,2,4 - Trichlorobenzene 94% 60 -140% P Ei ® 36 of 48 ®ACCUTEST. X13628 l,b• ,Io,•:s Blank Spike Summary doh Number: D13026 Account: PDCCOP PDC Project: PDC -PC5 & GG2 Profile Sampling Page 1 of 1 Sample File ID DF Analyzed By Prep Date Prep Batch Analytical Batch GGB231 -BS GB4270.D 1 05/07/10 DG n/a nla GGB231 The QC reported here applies to the following samples: D13026 -1, D13026 -2, D13026 -3, D13026 -4, D13026 -5, D13026 -6 Spike BSP BSP CAS No. Compound mg /kg mg /kg % Limits TPH -GRO (C6 -C10) 220 213 97 70 -130 CAS No. Surrogate Recoveries BSP Limits 120 -82 -1 1,2,4- Triichlorobenzene 108% 60 -140% Method: SW846 80I5B E© 37 of 48 ®ACCUTEST, D13028 c .,t.�•,.,.:, Blank Spike Summary Job Number: D13026 Account: PDCCOP PDC Project: PDC -PC5 & GG2 Profile Sampling Page 1 of 1 Sample GTB231 -BS File ID DF TB4270.D 1 Analyzed By 05 /07 /10 DG Prep Date Prep Batch Analytical Batch n/a n/a GTB231 The QC reported here applies to the following samples: D 13026 -1, D 13026 -2, D 13026 -3, D 13026 -4, D 13026 -6 CAS No. Compound 71 -43 -2 Benzene 100 -41 -4 Ethylbenzene 108 -88 -3 Toluene 95 -47 -6 o-Xylene in,p- Xylenc CAS No. Surrogate Recoveries 120 -82 -1 1,2,4 - Trichlorobenzene Spike BSP BSP ug /kg ug/kg % Limits 2720 2460 90 70 -130 4560 4430 97 70 -130 21200 19800 94 70 -130 6590 6580 100 70 -130 15000 14800 99 70 -I30 BSP Limits 97% 60 -140% Method: SW846 8021E 38 of 48 ACCUTEST o1sa26 L ,,. l•.,:,:= Blank Spike Summary Job Number: D13026 Account: PDCCOP PDC Project: PDC -PC5 & GG2 Profile Sampling Page 1 of 1 Sample File 1D DF Analyzed By Prep Date Prep Batch Analytical Batch GTB234 -13S TB4346.D 1 05/11/10 DG n/a n/a GT13234 The QC reported here applies to the following samples: D13026-5 CAS No. Compound Spike BSP BSP ug/kg ug/kg % Limits 7143 -2 Benzene 2720 2470 91 70 -130 100 -41 -4 Ethylbenzene 4560 4260 93 70 -130 108 -88 -3 Toluene 21200 19200 91 70 -130 95 -47 -6 o- Xylene 6590 6440 98 70 -130 m,p- Xylene 15000 14200 95 70 -130 CAS No. Surrogate Recoveries BSP Limits 120 -82 -1 1,2,4- Trichlorobenzene 89% 60 -140% Method: SW846 8021B gip 39 of 48 MIACCUTEST, 013026 :t•,.�i•U• „ Matrix Spike /Matrix Spike Duplicate Summary Job Number: D13026 PDCCOP PDC PDC -PC5 & (1G2 Profile Sampling Account: Project: Page l of 1 Sample D13026 -1MS D 13026 -1MSD D13026-1 File ID DF GB4272. D 1 GB4273, D 1 GB427 I . D 1 Analyzed By 05/07/10 DG 05/07/10 DG 05/07/10 DG Prep Date Prep Batch n/a n/a n/a n/a n/a n/a Analytical Batch GGB231 GGB231 0013231 The QC reported here applies to the following samples: 1313026 -1, 1313026 -2, 1313026 -3, D13026 -4, D13026 -5, 1313026 -6 CAS No. Compound TPH -GRO (C6 -C10) CAS No. Surrogate Recoveries 120 -82 -1 1,2,4- Triehlorobenzene D13026 -1 Spike MS MS mg /kg Q mg /kg mg/kg % 2870 1220 4030 95 MS MSD Method: SW846 8015B MSD MSD Limits mg/kg % RPD Rec /RPD 3930 87 3 62- 130/30 013026 -1 Limits 166 %* a I64 %* a 140% 60 -140% (a) Outside control limits due to matrix interference. In 40 of 48 ®ACCUTEST 013026 L 14, Matrix Spike /Matrix Spike Duplicate Summary Job Number: 1313026 Account: PDCCOP PDC Project: PDC -PC5 & GG2 Profile Sampling Page 1 of 1 Sample D13026-1MS D13026 -1MSD D13026-1 File ID DF TB4272.D 1 TB4273.D 1 TB427L.D 1 Analyzed By 05/07/10 DG 05/07/10 130 05/07/10 DG Prep Date Prep Batch n/a n/a n/a n/a n/a n/a Analytical Batch GTB231 GTB231 GT13231 The QC reported here applies to the following samples: 1313026 -1, 1313026 -2, 1313026 -3, 1313026 -4, 1313026 -6 CAS No. Compound 71 -43 -2 Benzene 100 -41 -4 Ethylbenzene 108 -88 -3 Toluene 95 -47 -6 o- Xylene m,p- Xylene CAS No. Surrogate Recoveries 120 -82 -1 1,2,4- Trichlorobenzene D13026 -1 ug /kg Q 1210 12900 17900 16900 131000 MS Spike ug/kg 15100 25400 118000 36700 83500 MS MS ug /kg % 14600 88 37200 96 130000 95 52900 98 212000 97 Method: SW846 8021E MSD MSD ug /kg % 14400 36300 128000 51600 204000 MSD D13026 -1 Limits 122% 121% 106% 60- 140% Limits RPD Rec /RPD 87 1 70- 130/30 92 2 62- 130/30 93 2 70- 130/30 95 2 65- 135/30 87 4 60- 140/30 NO 41 of 48 ACGUT€ST. 013026 L •/�� -, Matrix Spike /Matrix Spike Duplicate Summary Job Number: D13026 Account: PDCCOP PDC Project: PDC -PC5 & GG2 Profile Sampling Page 1 of 1 Sample D 12636 -20MS D12636 -20MSD D12636 -20 a File ID DF Analyzed By TB4348.D 1 05/11/10 DG TB4349.D 1 05 /11 /10 DG TB4347.D 1 05/11/10 DG Prep Date Prep Batch n/a n/a n/a n/a n/a n/a Analytical Batch GTB234 GTB234 GTB234 The QC reported here applies to the following samples: D13026-5 CAS No. Compound 71 -43 -2 Benzene 100 -414 Ethylbenzene 108 -88 -3 Toluene 95 -47 -6 o- Xylene m,p- Xylene CAS No. Surrogate Recoveries 120 -82 -1 1,2, 4-Trichlorobenzene (a) holdtime ok - ERA ampule D12636 -20 ug /kg Q Spike uglkg Method: SW846 8021B MS MS MSD MSD Limits ug /kg % ug/kg % RPD Rec /RPD 11500 27200 34800 86 35400 88 2 70- 130/30 52600 45600 92500 88 92900 88 0 62- 130/30 114000 212000 296000 86 300000 88 1 70- 130/30 44700 65900 105000 92 107000 95 2 65- 135/30 112000 150000 248000 91 251000 93 1 60- 140/30 MS MSD )312636 -20 Limits 129% 128% 120% 60 -140% © 42 of 48 ACCLJTEsT. ❑13026 I- .s,,. .:s InMountain States cif ACCUTEST L a L r a l o,, c L C'y ALL IN SHE , =lid 1.5351 FSY GC Semi - volatiles QC Data Summaries Includes the following where applicable: • Method Blank Summaries • Blank Spike Summaries • Matrix Spike and Duplicate Summaries Section 6 Ij 43 of 48 ACCUTEST. D13026 i,00•^i.,, Method Blank Summary Job Number: D13026 Account: PDCCOP PDC Project: PDC -PC5 & an Profile Sampling Page 1 of 1 Sample File ID DF Analyzed By Prep Date Prep Batch Analytical Batch 0P1823 -MB PD1223.D 1 05/07/10 CP 05/07/10 OP1823 GFD88 The QC reported here applies to the following samples: D13026 -1, D13026 -2, D13026 -3, D13026 -4, D13026 -5, D13026 -6 CAS No. Compound Result RL Units Q TP1 -1 -DRO (C10 -C28) ND 13 mg/kg CAS No. Surrogate Recoveries limits 84 -15 -1 o- Terphenyl 89% 63 -130% Method: SW846 -8015B ffi® 44 of 48 ACCUTEST. D13026 Lab i, >, •: > Blank Spike Summary Job Number: D13026 Account PDCCOP PDC Project: PDC -PC5 & GG2 Profile Sampling Pagel of 1 Sample File ID DF Analyzed By Prep Date Prep Batch Analytical Batch 0P1823 -BS FD1233.D 1 05/07/10 CP 05/07/10 01'1823 GFD88 The QC reported here applies to the following samples: D13026 -1, D13026 -2, D13026 -3, D13026 -4, D13026 -5, D13026 -6 Spike BSP BSP CA5 No. Compound mg /kg mg /kg % Limits TPH -DRO (C10 -C28) 667 803 120 70 -130 CAS No. Surrogate Recoveries 84 -15 -! o- Terphenyl BSP Limits 124% 63- 130% Method: SW846 -8015B 0 45 of 48 ACCUTEST. D13026 Matrix Spike /Matrix Spike Duplicate Summary Job Number: D13026 Account: PDCCOP PDC Project: PDC -PC5 & GG2 Profile Sampling Page 1 of 1 Sample File ID DF Analyzed By Prep Date Prep Batch Analytical Batch 0P1823 -MS FD1234.D 1 05/07/10 CP 05/07/10 OP1823 GFD88 OP1823-MSD FD1235.D 1 05/07/10 CP 05 /07 /10 OP1823 GFD88 D13026 -1 FD1225.D 1 05/07/10 CP 05/07/10 OP1823 GFD88 The QC reported here applies to the following samples: D13026 -1, D13026 -2, D13026 -3, D13026 -4, D13026 -5, D13026 -6 Method; SW846 -8015B D13026 -1 Spike MS MS MSD MSD Limits CAS No. Compound nig /kg Q mg/kg mg /kg % nig/kg % RPD Rec /RPD TPH -DRO (C10 -C28) 257 839 1080 98 1320 127 20 70- 130/30 CAS No. Surrogate Recoveries 84 -15 -1 o- Terphenyl MS MSD D13026 -1 Limits 112% 122% 85% 63-130% Eji 46 of 48 tACCUTE61 D13026 • . , . > ® Mountain States ®ACCUTEST Ld hr n r a 1 r, r 1e I .,LP. IN I NE GhIEMi*Sfl Y General Chemistry QC Data Summaries Includes the following where applicable: • Method Blank and Blank Spike Summaries • Duplicate Summaries • Matrix Spike Summaries Section 7 © 47 of 48 aACM:TEST 013026 ui,,,•:, METHOD sLANEC AND SPIKE RESULTS SUMMARY GENERAL CHEMISTRY Login Number: 013026 Account: PDCCDP - PDC Project; PDC -PC5 8 G02 Profile Sampling Analyte MB Spike BOP BSP QC Batch ID RL Result Units Amount Result %Recov limits Corrosivity as pH Cyanide Reactivity Sulfide Reactivity GN4234 0P1907/GN4268 GP1904/GN4262 10 1.5 0.0 0.0 su mg /kg mg /kg Associated Samples: Batch GN4234: 010026 -1, 013026-2, 013026 -3, 013026 -4, 1013026 -5, 013026 -6 Batch GP1904: 1213026 -1, 1213026 -2, 1)13026 -3, 013026 -4, 013026 -5, D13026 -6 Batch GP1907: 013026 -1, 013026 -2, 013026 -3, 013026 -4, D13026 -5, D13026 -6 01 outside of QC limits 8.00 13.6 65 8.00 0.0 40.0 100,0 0.1 61.5 99.3 - 100.78 0 -100% 50 -150% Page 1 On 48 of A8 12441:=LJTEEE311: D13026 Volume of Impacted Soil Actual Data Date I Vol. (yde) 'Site 'Material 2008 5/21/2008 955 Garden Gulch 4 Cond. 6/10/2008 399 Starkey Relay Battery Cond., PW 7/22/2008 0 Starkey 1 NA 8/15/2008 10 Starkey 5 Cond., PW 8/23/2008 169 Mesa 1 Cond., PW 8/27/2008 10 Starkey 3 Cond., PW 9/17/2008 1,472 Old Logan Dehy Cond., PW 9/29/2008 13 Mesa 19 PW 10/13/2008 5 Mesa 19 Cond. 10/22/2008 0 Puckett 264 -25 Drip Removal NA 10/22/2008 0 Section 36 Drip Removal NA 10/24/2008 1,590 Section 12 Pipeline Cond., PW 1 0/29/2008 1 ,605 Unocal 3 PW 11/20/2008 10 Mesa 5 Cond. 11/21/2008 10 Mesa 7 Cond., PW 12/6/2008 138 Mesa 11 PW 12/9/2008 10 Mesa 13 Cond. 12/11/2008 10 Starkey 2 Cond. 12/15/2008 5 Drip Removal at New Dehy Cond. 6,411 Note: Cond. = Condensate, PW = Produced Water Estimation of Volume of Impacted Soil for Permitting Basis Actual volume of impacted soil generated in 2008 = 6411 yd3 Assumed percent of soil impacted with produced water only = 25 % Safety Factor = 50 % Potential volume of condensate impacted soil for permit basis = 7212.4 yd3 Potential volume of prod. water impacted soil for permit basis = 2404.1 yd3 Estimation of Weight Percent of Hydrocarbon Liquid in the Soil for Permitting Basis High TPH of soil samples taken in 2008 = 9820.7 mg /kg Weight percent of hydrocarbon liquid in this soil sample = 1.0 % Safety Factor = 200 Potential weight percent of hydrocarbon liquid in the soil = 2.9 % Potential Emissions from Condensate Impacted Soil Assumptions: 1) Potential volume of impacted soil for permit basis = 7212.4 yd3 / yr Default soil density = 100.0 Ib / ft3 Weight percent of hydrocarbon liquid in the soil = 2.9 Potential weight of hydrocarbon liquid = 573728 Ib / yr 2) Conservatively assume that everything that volatilizes at 100 °F will be emitted. 3) Atmospheric pressure = Calculations 12 psia 'Component Mole°% Weight %1 Vapor Pressure at 100°F (psia) Volatile %3 Emissions (Ib /yr) Emissions (ton /yr) Carbon dioxide 0.0000 0.0000 -- 100.00 0.00 0.00 Nitrogen 0.0000 0.0000 -- 100.0_0 0.00 0.00 Methane 0.0287 0.0040 -- 100.00 22.95 0.01 Ethane 0.0543 0.0142 -- 100.00 81.47 0.04 Propane 0.2647 0.1017 188.650 _100.00 583.48 0.29 i- Butane 0.3645 0.1846 72.581 100.00 1059.10 0.53 n- Butane 0.5497 0.2784 51.706 100.00 1597.26 0.80 i- Pentane 1.2105 0.7610 20.443 100.00 4366.07 2.18 n- Pentane 1.0641 0.6690 15.575 100.00 3838.24 1.92 Cyclopentane 0.0619 0.0378 9.917 82.64 179.22 0.09 n- Hexane 2.1770 1.6348 4.960 41.33 3876.46 1.94 Cyclohexane 2.0005 1.4671 3.267 27.23 2291.57 1.15 Other hexanes 4.3508 3.2412 6.926 57.71 10732.18 5.37 Other heptanes 10.4926 9.1210 2.526 21.05 11014.78 5.51 Methylcyclohexane 8.0927 6.9248 1.609 13.41 5327.06 2.66 2,2,4- trimethylpentane (i- Octane) 0.0036 0.0036 1.709 14.24 2.94 0.00 Benzene 0.9455 0.6435 3.225 26.88 992.21 0.50 Toluene 5.2184 4.1898 1.033 8.61 2069.27 1.03 Ethylbenzene 0.4762 0.4406 0.372 3.10 78.28 0.04 Xylenes 6.8685 6.3545 0.311 2.59 945.06 0.47 Other octanes 18.3489 18.1494 0.632 5.27 5487.84 2.74 Nonanes 16.4954 18.2011 0.180 1.50 1564.41 0.78 Decanes plus 20.9294 27.5769 0.065 0.54 852.98 0.43 Sub -total 100.00 100.00 VOC Emissions = 28.43 API Gravity = Vapor Pressure' = Average MW of Decanes plus' = Average SG of Decanes plus1 = Notes: 55.37 60/60 0.87 PSIA & 100F 151.2 0.772 1) Empact Analytical Systems extended natural gas liquid analysis, June 1, 2009. 2) Gas Processors Suppliers Association, Engineering Data Book, Revised 10th Edition, 1994, Figure 23 -2, Physical Constants 3) The amount that a component volatilzes is estimated by ratioing the pure component's vapor pressure (at 100 °F) to the atmospheric pressure. Potential Emissions from Produced Water Impacted Soil Assumptions: 1) Potential volume of impacted soil for permit basis = 2404.1 yd3 / yr Default soil density = 100.0 Ib / ft3 Weight percent of hydrocarbon liquid in the soil = 2.9 °10 Potential weight of hydrocarbon liquid = 191243 Ib / yr 2) Conservatively assume that everything that volatilizes at 100 °F will be emitted. 3) Atmospheric pressure = Calculations 12 psia Component Mole %' Weight%' Vapor Pressure at 100°F2 (psia) Volatile %3 Emissions (Ib /yr) Emissions (ton /yr) Carbon dioxide 0.0000 0.0000 -- 100.00 , 0.00 0.00 Nitrogen 0.0000 0.0000 -- 100.00 0.00 0.00 Methane 0.0008 0.0006 -- 100.00 1.15 0.00 Ethane 0.0002 0.0006 -- 100.00 1.15 0.00 Propane 0.0001 0.0000 188.650 100.00 0.00 0.00 i- Butane 0.0002 0.0006 72.581 100.00 1.15 0.00 n- Butane 0.0001 0.0006 51.706 100.00 1.15 0.00 i- Pentane 0.0000 0.0000 20.443 100.00 0.00 0.00 n- Pentane 0.0000 0.0000 15.575 100.00 0.00 0.00 Cyclopentane 0.0000 0.0000 9,917 82.64 0.00 0.00 n- Hexane 0.0000 0.0000 4.960 41.33 0.00 0.00 Cyclohexane 0.0000 0.0000 3.267 27.23 0.00 0.00 Other hexanes 0.0000 0.0000 6.926 57.71 0.00 0.00 Other heptanes 0.0000 0.0000 2.526 21.05 0.00 0.00 Methylcyclohexane 0.0000 0.0000 1.609 13.41 0.00 0.00 2,2,4- trimethylpentane (i- Octane) 0.0000 0.0000 1.709 14.24 0.00 0.00 Benzene 0.0002 0.0011 3.225 26.88 0.57 0.00 Toluene 0.0003 0.0017 1.033 8.61 0.28 0.00 Ethylbenzene 0.0000 0.0000 0.372 3.10 0.00 0.00 Xylenes 0.0001 0.0006 0.311 2.59 0.03 0.00 Other octanes 0.0000 0.0000 0.632 5.27 0.00 0.00 Nonanes 0.0001 0.0006 0.180 1.50 0.02 0.00 Decanes plus 0.0001 0.0011 0.000 0.00 0.00 0.00 Water 99.99 99.99 -- -- -- - Sub -total 100.00 99.99 VOC Emissions = 0.002 API Gravity' Vapor Pressure' _ Average MW of Decanes plus' = Average SG of Decanes plus' = Notes: 9.99 60/60 0.04 PSIA & 100F 156.31 0.745 1) Empact Analytical Systems extended natural gas liquid analysis, June 2, 2009. 2) Gas Processors Suppliers Association, Engineering Data Book, Revised 10th Edition, 1994, Figure 23 -2, Physical Constants 3) The amount that a component volatilzes is estimated by ratioing the pure component's vapor pressure (at 100 °F) to the atmospheric pressure. * fEMPACT ANALYTICAL Alf* ;i i1 ;YSTEMS � INC. �li�. 111 161M.,k ARILWArAt 365 S. MAIN ST. BRIGHTON, CO 80601 303- 637 -0150 EXTENDED NATURAL GAS LIQUID ANALYSIS ( *DHA2 E & P TANK / GLYCALC INFORMATION PROJECT NO. : 200905157 ANALYSIS NO.: 01 COMPANY NAME : LT ENVIRONMENTAL ANALYSIS DATE: JUNE 1, 2009 ACCOUNT NO. : PDCW0915 SAMPLE DATE ; MAY 29, 2009 PRODUCER CYLINDER NO.: VOA VIAL # 1 LEASE NO. : SAMPLED BY : SCOTT GLEN NAME /DESCRIP : PICEANCE BASIN @ 1245; UNOCAL 6 NATURAL GAS CONDENSATE ** *FIELD DATA * ** SAMPLE PRES. : VAPOR PRES. : COMMENTS : SPOT SAMPLE TEMP. : AMBIENT TEMP.: GRAVITY . COMPONENT Mole % Wt % LV % CARBON DIOXIDE 0.0000 0.0000 0.0000 NITROGEN (AIR) 0.0000 0.0000 0.0000 METHANE 0.0287 0.0040 0.0101 ETHANE 0.0543 0.0142 0.0303 PROPANE 0.2647 0.1017 0.1521 1- BUTANE 0.3645 0.1846 0.2480 N- BUTANE 0.5497 0.2784 0.3609 I- PENTANE 1,2105 0.7610 0.9226 N- PENTANE 1.0641 0.6690 0.8020 CYCLOPENTANE (N -05) 0.0619 0.0378 0.0379 N- HEXANE 2.1770 1.6348 1.8641 CYCLOHEXANE (OTHER 06) 2.0005 1.4671 1.4173 OTHER HEXANES 4.3508 3.2412 3.5546 OTHER HEPTANES 10.4926 9.1210 9.8318 METHYLCYCLOHEXANE (OTHER C6) 8.0927 6.9248 6.7654 2,2,4 TRIMETHYLPENTANE 0.0036 0.0036 0.0038 BENZENE 0.9455 0.6435 0.5515 TOLUENE 5.2184 4.1898 3.6272 ETHYLBENZENE 0.4762 0.4406 0.3811 XYLENES 6.8685 6.3545 5.5234 OTHER OCTANES 18.3489 18.1494 18.7980 OCTANES PLUS - - -- 63.1220 - - -. 70.7261 - - -- NONANES 16.4954 18.2011 18.1396 DECANES PLUS 20.9294 27.5769 26.9783 SUB TOTAL 99.9979 99.9990 100.0000 ALCOHOLS 0.0021 0.0010 0.0000 TOTAL 100.0000 100.0000 100.0000 API Gravity = Vapor Pressure = Average Molecular Weight of Decanes plus Average Specific Gravity of Decanes plus 55.37 60/60 0.87 PSIA & 100 F 151.20 0.7720 THE DATA PRESENTED HEREIN HAS BEEN ACQUIRED THROUGH JUDICIOUS APPLICATION OF CURRENT STATE -OF -THE ART ANALYTICAL TECHNIQUES. THE APPLICATIONS OF THIS INFORMATION IS THE RESPONSIBILITY OF THE USER. EMPACT ANALYTICAL SYSTEMS, INC. ASSUMES NO RESPONSIBILITY FOR ACCURACY OF THE REPORTED INFORMATION NOR ANY CONSEQUENCES OF ITS APPLICATION. 69.8242 :r 11r * 7/S { 44 �EMPACT ANALYTICAL` II':- SYSTEMS iNc- \�IL 411 .7 Rpm, "k111�. 365 S. MAIN ST. BRIGHTON, CO 80601 303- 637 -0150 EXTENDED NATURAL GAS LIQUID ANALYSIS ( *DHA) E & P TANK 1 GLYCALC INFORMATION PROJECT NO. : 200905157 ANALYSIS NO.: 02 COMPANY NAME : LT ENVIRONMENTAL ANALYSIS DATE: JUNE 2, 2009 ACCOUNT NO. : PDCW0915 SAMPLE DATE : MAY 29, 2009 PRODUCER . CYLINDER NO. ; VOA VIAL # 2 LEASE NO. : SAMPLED BY : SCOTT GLEN NAME /DESCRIP : PICEANCE BASIN @ 1300; UNOCAL 6 PRODUCED WATER ** *FIELD DATA * ** SAMPLE PRES. : VAPOR PRES. : COMMENTS . SPOT SAMPLE TEMP. : AMBIENT TEMP.: GRAVITY . COMPONENT Mole % Wt % LV % CARBON DIOXIDE 0.0000 0.000 0.0000 NITROGEN (AIR) 0.0000 0.0000 0.0000 METHANE 0.0008 0.0006 0.0017 ETHANE 0.0002 0.0006 0.0017 PROPANE 0.0001 0.0000 0.0000 1- BUTANE 0.0002 0.0006 0.0008 N- BUTANE 0.0001 0.0006 0.0008 I- PENTANE 0.0000 0.0000 0.0000 N- PENTANE 0.0000 0.0000 0.0000 CYCLOPENTANE (N -05) 0.0000 0.0000 0.0000 N- HEXANE 0.0000 0.0000 0.0000 CYCLOHEXANE (OTHER C6) 0.0000 0.0000 0.0000 OTHER HEXANES 0.0000 0.0000 0.0000 OTHER HEPTANES 0.0000 0.0000 0.0000 METHYLCYCLOHEXANE (OTHER C6) 0.0000 0.0000 0.0000 2,2,4 TRIMETHYLPENTANE 0.0000 0.0000 0.0000 BENZENE 0.0002 0.0011 0.0008 TOLUENE 0.0003 0.0017 0.0017 ETHYLBENZENE 0.0000 0.0000 0.0000 XYLENES 0.0001 0.0006 0.0008 OTHER OCTANES 0.0000 0.0000 0.0000 OCTANES PLUS --- 0.0003 ---- 0.0023 - -- NONANES 0.0001 0.0006 0.0008 DECANES PLUS 0.0001 0.0011 0.0017 SUB TOTAL 0.0022 0.0075 0.0108 WATER 99.9942 99.9853 99.9800 ALCOHOLS 0.0029 0.0061 0.0075 GLYCOLS 0.0007 0.0011 0.0017 TOTAL 100.0000 100.0000 100.0000 API Gravity = 9.99 60/60 Vapor Pressure = 0.04 PSIA & 100 F Average Molecular Weight of Decanes plus = 156.3] Average Specific Gravity of Decanes plus = 0.7450 THE DATA PRESENTED HEREIN HAS BEEN ACQUIRED THROUGH JUDICIOUS APPLICATION OF CURRENT STATE-OF-THE ART ANALYTICAL TECHNIQUES. THE APPLICATIONS OF THIS INFORMATION IS THE RESPONSIBILITY OF THE USER. EMPACTANALYTICAL SYSTEMS, INC. ASSUMES NO RESPONSIBILITY FOR ACCURACY OF THE REPORTED INFORMATION NOR ANY CONSEQUENCES OF ITS APPLICATION. 0.0033 5ummit ,scientific 741 Corporate Circle — Suite I • Golden, Colorado 80401 303.277.9310 - laboratory ♦ 303.374.5933 - fax May 06, 2009 Scott Ghan LT Environmental, Inc. 4600 West 60th Avenue Arvada, CO 80003 RE: PDC - Deep Well Pad Frac Tank Sampling Enclosed are the results of analyses for samples received by Summit Scientific on 04/20/09 10:00. If you have any questions concerning this report, please feel free to contact me. Sincerely, f Ben Shrewsbury Vice President / Laboratory Director 2 LT Environmental, Inc. 4600 West 60th Avenue Arvada CO, 80003 Project: PDC - Deep Well Pad Frac Tank Sampling Project Number: PDCW 0908 Project Manager: Scott Ghan Reported: 05/06/09 15:21 ANALYTICAL REPORT FOR SAMPLES Sample ID Laboratory ID Matrix Date Sampled Date Received CO1 @1' R904087 -01 Soil 04/17/09 13:00 04/20/09 10:00 E Summit Scientific The results in this report apply to the samples analyzed in accordance with the chain of custody document. This analytical report must be reproduced in its entirety. }/17/ Page 1 of 10 Special Instrnctioiis s. 4 A1 °L 5IP I, 14 cu- 1'X- (ASVaadg) .rau o ■ RI 8 ea 3 - IR cY. O :. # Isisas ...al, eue:l a - �V .7.3713.41. punw.;) C. r6aads1 aagao sua '[lN H s_,—, 1uo- n _rag wn 1.,.1 7', v c paid .uxg asuLL vi pauc ursr appro 4r— 1", v E Summit Scientific The results in this report apply to the samples analyzed in accordance with the chain of custody document. This analytical report must be reproduced in its entirety. }/17/ Page 1 of 10 2 LT Environmental, Inc. Project: PDC - Deep Well Pad Frac Tank Sampling 4600 West 60th Avenue Arvada CO, 80003 Project Number: PDCW 0908 Project Manager: Scott Ghan Reported: 05/06/09 15:21 CO1 @1' R904087-01 (Soil) Summit Scientific Total Petroleum Hydrocarbons by 8015 Date Sampled: 04/17/09 13:00 Analyte Result Reporting Limit Units Dilution Batch Prepared Analyzed Method Notes C6 -C10 (GRO) C10 -C28 (DRO) C28 -C36 (ORO) C6 -C36 TPH 1300 5800 ND 7100 50 mg/kg 50 50 50 1 9042403 04/24/09 04/25/09 8015 Full Carbon Chain Date Sampled: 04/17/09 13:00 Analyte Result Reporting Limit Units Dilution Batch Prepared Analyzed Method Notes Surrogate: o- Terphenyl Surrogate: Trifluorotoluene Volatile Organic Compounds by EPA Method 8260B 506 77.7 -123 124 % 73.9 -120 If S -02 S -02 Date Sampled: 04/17/09 13:00 Analyte Result Reporting Limit Units Dilution Batch Prepared Analyzed Method Notes Benzene Toluene Ethylbenzene Xylenes (total) 5.1 190 78 1200 0.50 mg/kg 5.0 " 5.0 5.0 100 9042404 04/24/09 04/25/09 EPA 8260B 1000 Date Sampled: 04/17/09 13:00 Analyte Result Reporting Limit Units Dilution Batch Prepared Analyzed Method Notes Surrogate: 1,2- Dichloroethane -d4 Surrogate: Toluene -d8 Surrogate: 4- Bromofluorobenzene Physical Parameters by APHA/ASTM /EPA Methods 117 102 103 77.3 -121 91.4 -107 85.3 -109 IF Summit Scientific The results in this report apply to the samples analyzed in accordance with the chain of custody document. This analytical report must be reproduced in its entirety. Page 2 of 10 2 LT Environmental, Inc. Project: PDC - Deep Well Pad Frac Tank Sampling 4600 West 60th Avenue Arvada CO, 80003 Project Number: PDCW 0908 Project Manager: Scott Ghan Reported: 05/06/09 15:21 CO1 @1' R904087-01 (Soil) Summit Scientific Physical Parameters by APHA/ASTM /EPA Methods Date Sampled: 04/17/09 13:00 Analyte Result Reporting Limit Units Dilution Batch Prepared Analyzed Method Notes Specific Conductance (EC) 2.25 0.00100 mhos /cm 1 9042103 04/21/09 04/21/09 SM 2510b /mod Date Sampled: 04/17/09 13:00 Analyte Result Reporting Limit Units Dilution Batch Prepared Analyzed Method Notes pH 7.4 Evergreen Analytical - Hot Water Soluble Boron, Soil Basis pH Units 9042102 04/21/09 If EPA 9045B Date Sampled: 04/17/09 13:00 Analyte Result Reporting Limit Units Dilution Batch Prepared Analyzed Method Notes Boron 1.3 0.0099 mg/L 1 9050405 05/02/09 05/04/09 GUPTA Evergreen Analytical - 6010 Hexavalent Chromium, Soil (3060A Mod Digest) Z -01 Date Sampled: 04 /17/09 13:00 Analyte Result Reporting Limit Units Dilution Batch Prepared Analyzed Method Notes Chromium, Hexavalent Evergreen Analytical - Metals ND 1.30 mg /kg 1 9050405 04/27/09 04/29/09 SW6010B Cr6 Date Sampled: 04/17/09 13:00 Analyte Result Reporting Limit Units Dilution Batch Prepared Analyzed Method Notes Arsenic Cadmium Chromium Copper Lead Nickel 3.8 1.7 mg /kg ND 0.34 1 9050405 05/02/09 05/06/09 SW6010B 12 0.34 ,, " ,, 30 0.17 ,, ,, ,, ,, ,, ,, 7.0 2.5 „ „ „ „ 9.2 1.0 Summit Scientific 7// The results in this report apply to the samples analyzed in accordance with the chain of custody document. This analytical report must be reproduced in its entirety. Page 3 of 10 2 LT Environmental, Inc. Project: PDC - Deep Well Pad Frac Tank Sampling 4600 West 60th Avenue Arvada CO, 80003 Project Number: PDCW 0908 Project Manager: Scott Ghan Reported: 05/06/09 15:21 Evergreen Analytical - Metals Selenium Silver Zinc CO1 @1' R904087-01 (Soil) Summit Scientific Evergreen Analytical - Mercury ND ND 26 3.4 mg /kg 1 9050405 05/02/09 05/06/09 SW6010B 1.0 " " 1.0 II ,I II II II II Date Sampled: 04/17/09 13:00 Analyte Result Reporting Limit Units Dilution Batch Prepared Analyzed Method Notes Mercury 0.17 0.019 mg /kg Evergreen Analytical - Trivalent Chromium, Calculated, Soil Basis 1 9050405 04/29/09 04/29/09 SW7471A Date Sampled: 04/17/09 13:00 Analyte Result Reporting Limit Units Dilution Batch Prepared Analyzed Method Notes Chromium +3 Calculated 12.0 0.300 mg/kg 1 9050405 04/30/09 05/02/09 CalcCr+3 Sunnnit Scientific The results in this report apply to the samples analyzed in accordance with the chain of custody document. This analytical report must be reproduced in its entirety. )7// Page 4 of 10 2 LT Environmental, Inc. 4600 West 60th Avenue Arvada CO, 80003 Project: PDC - Deep Well Pad Frac Tank Sampling Project Number: PDCW 0908 Project Manager: Scott Ghan Reported: 05/06/09 15:21 Total Petroleum Hydrocarbons by 8015 - Quality Control Summit Scientific Analyte Result Reporting Limit Units Spike Source %REC RPD Level Result %REC Limits RPD Limit Notes Batch 9042403 - EPA 3550A Blank (9042403 -BLK1) C6 -C10 (GRO) C10 -C28 (DRO) C28 -C36 (ORO) C6 -C36 TPH LCS (9042403 -BS1) C6 -C10 (GRO) C10 -C28 (DRO) LCS (9042403 -BS2) C6 -C10 (GRO) C10 -C28 (DRO) Prepared & Analyzed: 04/24/09 LCS Dup (9042403 -BSD1) C6 -C10 (GRO) C10 -C28 (DRO) LCS Dup (9042403 -BSD2) C6 -C10 (GRO) C10 -C28 (DRO) ND ND ND ND ND 485 495 ND 50 mg /kg 50 50 50 50 mg /kg 50 Prepared & Analyzed: 04/24/09 70 -130 500 97.0 83.3 -127 Prepared & Analyzed: 04/24/09 50 mg /kg 50 ND 428 50 mg /kg 50 519 95.4 70 -130 83.3 -127 Prepared & Analyzed: 04/24/09 70 -130 500 85.6 83.3 -127 Prepared & Analyzed: 04/24/09 20 12.5 15 Matrix Spike (9042403 -MS1) C6 -C10 (GRO) C10 -C28 (DRO) Matrix Spike (9042403 -MS2) 492 ND 50 mg /kg 50 Source: R904087 -01 ND 50 mg /kg 12100 50 Source: R904087 -01 519 94.8 70 -130 0.608 20 83.3 -127 Prepared & Analyzed: 04/24/09 15 1300 70 -130 500 5800 NR 75.8 -126 Prepared & Analyzed: 04/24/09 QM -4X C6 -C10 (GRO) C10 -C28 (DRO) 1930 ND 50 mg/kg 50 " 519 1300 5800 121 70 -130 75.8 -126 Summit Scientific )7// The results in this report apply to the samples analyzed in accordance with the chain of custody document. This analytical report must be reproduced in its entirety. Page 5 of 10 2 LT Environmental, Inc. Project: PDC - Deep Well Pad Frac Tank Sampling 4600 West 60th Avenue Arvada CO, 80003 Project Number: PDCW 0908 Project Manager: Scott Ghan Reported: 05/06/09 15:21 Total Petroleum Hydrocarbons by 8015 - Quality Control Summit Scientific Analyte Result Reporting Spike Source %REC RPD Limit Units Level Result %REC Limits RPD Limit Notes Batch 9042403 - EPA 3550A Matrix Spike Dup (9042403 -MSD1) C6 -C10 (GRO) C10 -C28 (DRO) Source: R904087 -01 Prepared & Analyzed: 04 /24/09 ND 50 mg /kg 1300 70 -130 20 23700 50 500 5800 NR 75.8 -126 64.8 13.6 QM -4X Matrix Spike Dup (9042403 -MSD2) Source: R904087 -01 Prepared & Analyzed: 04/24/09 C6 -C10 (GRO) 2130 50 mg /kg 519 1300 160 70 -130 9.85 20 QM -4X C10 -C28 (DRO) ND 50 If 5800 75.8 -126 13.6 Summit Scientific The results in this report apply to the samples analyzed in accordance with the chain of custody document. This analytical report must be reproduced in its entirety. Page 6 of 10 2 LT Environmental, Inc. Project: PDC - Deep Well Pad Frac Tank Sampling 4600 West 60th Avenue Arvada CO, 80003 Project Number: PDCW 0908 Project Manager: Scott Ghan Reported: 05/06/09 15:21 Volatile Organic Compounds by EPA Method 8260B - Quality Control Summit Scientific Analyte Result Reporting Spike Source %REC RPD Limit Units Level Result %REC Limits RPD Limit Notes Batch 9042404 - EPA 5030 Soil MS Blank (9042404 -BLK1) Benzene Toluene Ethylbenzene Xylenes (total) Prepared: 04/24/09 Analyzed: 04/25/09 ND 0.0050 mg/kg ND 0.0050 ND 0.0050 ND 0.0050 Surrogate: 1, 2 -Di chloroethane -d4 Surrogate: Toluene -d8 Surrogate: 4- Bromofluorobenzene 0.0476 0.0401 0.0397 If fl 0.0400 0.0400 0.0400 119 77.3 -121 100 91.4 -107 99.3 85.3 -109 LCS (9042404 -BS1) Prepared: 04/24/09 Analyzed: 04/25/09 Benzene 0.0896 0.0050 mg/kg 0.100 89.6 70 -114 Toluene 0.0935 0.0050 0.100 93.5 72.7 -116 Surrogate: 1,2- Dichloroethane -d4 Surrogate: Toluene -d8 Surrogate: 4- Bromofluorobenzene 0.0396 0.0439 0.0396 0.0400 0.0400 0.0400 99.0 77.3 -121 110 91.4 -107 99.0 85.3 -109 LCS Dup (9042404 -BSD1) Prepared: 04/24/09 Analyzed: 04/25/09 Benzene 0.0895 0.0050 mg/kg 0.100 89.5 70 -114 0.112 8.14 Toluene 0.0936 0.0050 " 0.100 93.6 72.7 -116 0.107 7.88 Surrogate: 1,2- Dichloroethane -d4 Surrogate: Toluene -d8 Surrogate: 4- Bromofluorobenzene 0.0177 0.0418 0.0391 0.0400 0.0400 0.0400 44.2 77.3 -121 104 91.4 -107 97.8 85.3 -109 Matrix Spike (9042404 -MS1) Source: R904096-01 Prepared: 04/24/09 Analyzed: 04/25/09 Benzene 0.665 0.0050 mg/kg 0.100 0.85 NR 66.8 -117 QM -4X Toluene 1.37 0.0050 " 0.100 3.3 NR 71.5 -117 QM -4X Surrogate: 1, 2 -Di chloroethane -d4 Surrogate: Toluene -d8 Surrogate: 4- Bromofluorobenzene 0.0468 0.0503 0.0401 If 0.0400 0.0400 0.0400 117 77.3 -121 126 91.4 -107 100 85.3 -109 S -02 Summit Scientific The results in this report apply to the samples analyzed in accordance with the chain of custody document. This analytical report must be reproduced in its entirety. )7// Page 7 of 10 2 LT Environmental, Inc. Project: PDC - Deep Well Pad Frac Tank Sampling 4600 West 60th Avenue Arvada CO, 80003 Project Number: PDCW 0908 Project Manager: Scott Ghan Reported: 05/06/09 15:21 Volatile Organic Compounds by EPA Method 8260B - Quality Control Summit Scientific Analyte Result Reporting Spike Source %REC RPD Limit Units Level Result %REC Limits RPD Limit Notes Batch 9042404 - EPA 5030 Soil MS Matrix Spike Dup (9042404 -MSD1) Source: 8904096 -01 Prepared: 04/24/09 Analyzed: 04/25/09 Benzene 0.789 0.0050 mg/kg 0.100 0.85 NR 66.8 -117 17.1 17.8 QM -4X Toluene 1.81 0.0050 0.100 3.3 NR 71.5 -117 27.7 14.4 QM -4X Surrogate: 1,2-Dichloroethane-d4 Surrogate: Toluene -d8 Surrogate: 4- Bromofluorobenzene 0.0493 0.0492 0.0402 0.0400 0.0400 0.0400 123 77.3 -121 123 91.4 -107 100 85.3 -109 S -02 S -02 Summit Scientific The results in this report apply to the samples analyzed in accordance with the chain of custody document. This analytical report must be reproduced in its entirety. )7// Page 8 of 10 2 LT Environmental, Inc. Project: PDC - Deep Well Pad Frac Tank Sampling 4600 West 60th Avenue Arvada CO, 80003 Project Number: PDCW 0908 Project Manager: Scott Ghan Reported: 05/06/09 15:21 Physical Parameters by APHA /ASTM /EPA Methods - Quality Control Summit Scientific Analyte Result Reporting Spike Source %REC RPD Limit Units Level Result %REC Limits RPD Limit Notes Batch 9042102 - General Preparation Duplicate (9042102 -DUP1) pH Batch 9042103 - General Preparation Source: 8904087 -01 Prepared & Analyzed: 04 /21/09 7.5 pH Units 7.4 1.34 20 Duplicate (9042103 -DUP1) Source: R904087 -01 Prepared & Analyzed: 04/21/09 Specific Conductance (EC) 2.45 0.00100 mhos /cm 2.25 8.51 20 Summit Scientific The results in this report apply to the samples analyzed in accordance with the chain of custody document. This analytical report must be reproduced in its entirety. )7// Page 9 of 10 52 LT Environmental, Inc. Project: PDC - Deep Well Pad Frac Tank Sampling 4600 West 60th Avenue Arvada CO, 80003 Project Number: PDCW 0908 Project Manager: Scott Ghan Reported: 05/06/09 15:21 Notes and Definitions Z -01 Analyte detected in the associated Method Blank, value not subtracted from result S -02 The surrogate recovery for this sample cannot be accurately quantified due to interference from coeluting organic compounds present in the sample extract. QM -4X The spike recovery was outside of QC acceptance limits for the MS and/or MSD due to analyte concentration at 4 times or greater the spike concentration. The QC batch was accepted based on LCS and/or LCSD recoveries within the acceptance limits. DET Analyte DETECTED ND Analyte NOT DETECTED at or above the reporting limit NR Not Reported dry Sample results reported on a dry weight basis RPD Relative Percent Difference Summit Scientific The results in this report apply to the samples analyzed in accordance with the chain of custody document. This analytical report must be reproduced in its entirety. )7// Page 10 of 10 LabNumber Analysis Analyte Items for Project Manager Review Exception 9042403 -BS2 9042404 -MS1 9042404 -MS1 9042404 -BSD1 9042404 -MSD1 9042404 -MSD1 R904087 -01 R904087 -01 9042403-MSD1 9042403 -BSD1 9042404 -MSD1 9042403 -BS1 9042403 -MSD2 9042403-MSD1 9042403 -MS2 9042403 -MS1 9042403 -BSD2 9042403 -MSD2 R904087 -01 R904087 -01 R904087 -01 9042404-MSD1 9042404-MSD1 9042404 -MSD1 9042404-MSD1 9042404 -MS1 9042403 -MS 1 9042404 -MS1 R904087 -01 8015 Full Carbon Chain 8260B BTEX TXYL 8260B BTEX TXYL 8260B BTEX TXYL 8260B BTEX TXYL 8260B BTEX TXYL 8015 Full Carbon Chain 8015 Full Carbon Chain 8015 Full Carbon Chain 8015 Full Carbon Chain 8260B BTEX TXYL 8015 Full Carbon Chain 8015 Full Carbon Chain 8015 Full Carbon Chain 8015 Full Carbon Chain 8015 Full Carbon Chain Conductivity -120.1 8260B BTEX TXYL 8015 Full Carbon Chain 8015 Full Carbon Chain C10 -C28 (DRO) Toluene Benzene 1,2- Dichloroethane -d4 Toluene Benzene Trifluorotoluene o- Terphenyl C10 -C28 (DRO) C6 -C10 (GRO) 1,2- Dichloroethane -d4 C6 -C10 (GRO) C10 -C28 (DRO) C6 -C10 (GRO) C10 -C28 (DRO) C6 -C10 (GRO) (Soil) (Soil) C10 -C28 (DRO) C6 -C10 (GRO) EA - Hot Water Soluble B Boron 8015 Full Carbon Chain Trifluorotoluene 8015 Full Carbon Chain o- Terphenyl 8260B BTEX TXYL 8260B BTEX TXYL 8260B BTEX TXYL 8260B BTEX TXYL 8260B BTEX TXYL Toluene -d8 Toluene Benzene 1,2- Dichloroethane -d4 Toluene -d8 8015 Full Carbon Chain C10 -C28 (DRO) 8260B BTEX TXYL Benzene EA - Hot Water Soluble B No spike level This is a modified report Exceeds lower control limit Exceeds lower control limit Exceeds lower control limit Exceeds lower control limit Exceeds lower control limit Exceeds upper control limit Exceeds upper control limit Exceeds upper control limit No spike level Exceeds upper control limit No spike level No spike level No spike level No spike level No spike level Special Units Used Special Units Used VERSION 5.8.5:2709 No spike level QM -4X: The spike recovery was outside of QC acceptance limits for the MS and/or MSD due to analyte concentration at 4 times or greater the spike concentration. The QC batch was accepted based on LCS and/or LCSD recoveries within the acceptanc Z -01: Analyte detected in the associated Method Blank, value not subtracted from result S -02: The surrogate recovery for this sample cannot be accurately quantified due to interference from coeluting organic compounds present in the sample extract. S -02: The surrogate recovery for this sample cannot be accurately quantified due to interference from coeluting organic compounds present in the sample extract. S -02: The surrogate recovery for this sample cannot be accurately quantified due to interference from coeluting organic compounds present in the sample extract. QM -4X: The spike recovery was outside of QC acceptance limits for the MS and/or MSD due to analyte concentration at 4 times or greater the spike concentration. The QC batch was accepted based on LCS and/or LCSD recoveries within the acceptanc QM -4X: The spike recovery was outside of QC acceptance limits for the MS and/or MSD due to analyte concentration at 4 times or greater the spike concentration. The QC batch was accepted based on LCS and/or LCSD recoveries within the acceptanc S -02: The surrogate recovery for this sample cannot be accurately quantified due to interference from coeluting organic compounds present in the sample extract. S -02: The surrogate recovery for this sample cannot be accurately quantified due to interference from coeluting organic compounds present in the sample extract. Exceeds upper control limit QM -4X: The spike recovery was outside of QC acceptance limits for the MS and/or MSD due to analyte concentration at 4 times or greater the spike concentration. The QC batch was accepted based on LCS and/or LCSD recoveries within the acceptanc Sampled - >Prepared > 14.00 days