ARCHIVED REPORTS_XR0004246 - Laserfiche WebLink

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Groundwater Monitoring Well Installation All three of the borings were converted into groundwater morutonng wells by installing 2-inch diameter, flush-threaded, Schedule 40 PVC casing with 0 020-inch factory-slotted screen Approximately 20 feet of screen were placed at or near the bottom of each of the borings An RMC 2112 sand pack, or equivalent, was placed in the annular space across the entire screened interval, and extends approximately 2 feet above the top of the screen for the well A 5 foot bentonite transition seal was placed atop the sand pack, and a Portland cement seal extends from the bentonite transition seal to the ground surface The boring logs show well construction details The wells were developed and sampled several days after completion The development procedure for each well consisted of pumping or bailing water from the well until the water was visibly clear, the well goes dry, or until a maximum of ten casing volumes was removed After development, water levels were allowed to partially recover Groundwater samples were then collected using a disposable teflon bailer, placed into appropriate EPA- approved containers, labeled, placed on ice, and transported to the laboratory accompanied by chain-of-custody documentation The newly installed wells were surveyed by Morrow Surveying, a California State Licensed Surveyor The well casings were surveyed to the nearest 0 01 feet in elevation to a known benchmark Laboratory Analysis for Soil and Groundwater Samples Analyses for TPH-g, benzene, toluene, ethylbenzene, xylenes (BTEX compounds), and methanol were performed by EPA Methods 8015 (modified) and 8020 Analysis for oxygenates other than methanol was performed by EPA Method 8260 Analysis for volatile organic compounds (VOCs) was performed by EPA Method 8010 Analysis for organic lead was performed by LUFT-DHS Analysis for dissolved lead was performed by EPA - 200 Series Methods i