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I <br /> 1.4 Problem Definition/Background <br /> Varra Companies has submitted a proposal to reclaim approximately I I acres of a mined out, <br /> flooded gravel quarry using coal ash as fill material. Numerous permits have been submitted <br /> proposing bench scale testing followed by a small scale field study to evaluate the economic and <br /> technical feasibility of using coal ash as fill material in saturated conditions. The proposed field <br /> study consists of placing 400 tons of coal ash below the water table at the Varra gravel quarry in <br /> Weld County,Colorado <br /> Five different leaching experiments were conducted in order to evaluate coal ash leaching <br /> potentials. Two of the leaching experiments compared element and compound water quality for <br /> different pH ranges relative to effluent pore volume. However, the data generated from the <br /> different leaching tests were not comparable to each other or to water quality standards. It was <br /> recommended by various member of the Colorado Department of Public Health and Environment <br /> (CDPH&E) that additional leaching tests be performed that would simulate, to the extent <br /> possible, conditions that would be encountered at the Varra property. A modified form of ASTM <br /> D 4874-95 Standard Test Method for Leaching Solid Material in Column Apparatus was used to <br /> simulate field conditions. Testing results have been submitted as par[ of a permit application to <br /> conduct the pilot study. <br /> 1.5 Intended Usage of Data <br /> CGRS will use the data obtained in a variety of ways. The major applications of data are: <br /> Health and Safety—Data are used to determine concentration of chemicals to which workers will be <br /> or are being exposed. <br /> Site Characterization—Data are used to determine local physical and chemical properties of soil and <br /> water at the Varra properly. Samples of soils, surface and ground water will be analyzed in the field <br /> using portable or transportable instruments or sent to the laboratory for certified chemical analyses. <br /> Project Feasibility—Data obtained from the pilot study will be used to assess the feasibility of large <br /> scale reclamation using coal ash. <br /> Risk Assessment — Data are used to calculate the effects of target analytes upon human health and <br /> other environmental receptors. Column study data will be compared to field data to assess the <br /> validity of column leaching studies and analytical solute transport and groundwater flow solutions. <br /> 1.6 Project Task/Description <br /> The purpose of the pilot project is to determine the feasibility of using coal ash as fill material in <br /> saturated conditions. This project will be accomplished by submitting required permits in <br /> combination with conducting bench scale leaching tests and a small scale ash burial and water <br /> quality monitoring program. The permit submittals are required as coal ash is classified as a solid <br /> waste and as such is subject to regulation under RCRA. The laboratory testing and proposed field <br /> tests are being conducted to fulfill permit requirements as well as provide assurance to all parties <br /> involved the placement of coal ash below the water table at this specific site will not cause <br /> adverse environmental impacts. <br /> The scope of work for this project involves, development of Health and Safety and site-specific <br /> work plans, field investigations, laboratory analysis of water samples. analysis of hydraulic and <br /> hydrogeologic properties,and the preparation of a report detailing the results of the investigation. <br /> Varra Companies <br /> Quality Assurance Project Plan <br /> Paee 2 <br />