2010-07-30_HYDROLOGY - M1977526 (4)

Home Browse Search

6 Environmental Monitoring Plans The Site will have a groundwater monitoring program. A methane gas monitoring program is not needed because the inert materials placed at the site will not generate methane gas. 6.1 Groundwater Monitoring Program The wells in the groundwater monitoring network are shown as MW-1, MW-2, MW-3 and MW-4 on the map in Appendix V. The wells will be installed for up-gradient and down-gradient groundwater monitoring. Four monitoring wells are planned for the detection monitoring in the alluvial aquifer. The two up-gradient wells are MW-2 and MW-3 and are located on the south and southeastern boundaries of the site. Down gradient wells are MW-1 and MW-4 and are located along the northeast and northwest boundaries of the site. The groundwater monitoring well locations are identified on the map in Appendix V and will be surveyed for location and elevations soon after installation. The groundwater monitoring wells will be installed to bedrock capturing the entire alluvial aquifer interval. Wells will be screened in the alluvial aquifer to depth and solid pipe will complete the well from the water level to approximately 3 feet above ground surface. The surface portion will be protected with a solid metal casing embedded into concrete. The wells will be protected with a bollards as needed to protect the well. A typical groundwater monitoring well diagram is shown in Appendix VII. All groundwater monitoring wells will be installed according to applicable standards and will be logged and observed to document soil lithography, color, and moisture content. Prior to installing groundwater monitoring wells, a notice of intent to construct monitoring holes will be filed with the Colorado Division of Water Resources of the State Engineer's Office. The monitoring wells will be developed to remove sediment and restore natural conductivity of the alluvial aquifer. 6.2 Groundwater Sampling and Analysis Requirements Groundwater will be analyzed for the analytes in Appendix IA and IB of the CDPHE Regulations Pertaining to Solid Waste Sites and Facilities for the first eight sampling events to establish background conditions. After the background samples are taken the list of analytes may be reduced to the ones that are most applicable to the types of inert materials placed at the site. The most applicable analytes will likely include at a minimum all inorganic constituents, cations and anions. Either Total Organic Carbon or the list of organic constituents will likely be used for detection of organics. The shortened list of analytes will be approved by CDPHE prior to discontinuing the sampling. AFS Frei-Henderson Inert Fill Page 17 of 23 MOLEN 8v ASSOCIATES, LLC