COMPLIANCE INFO_1991-1997 - Laserfiche WebLink

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1] City of Stockton November 14, 1995 was not producing any water. Upon review of the contract with the City of Stockton, Twining concluded that, while the installation of the well was technically correct, the well did not fulfill the terms of the contract (delivery of a 100 -foot deep well). In order to rectify the situation, Twining is proposing to drill a new well adjacent to the existing MW -14. The new well is intended to monitor migration of impacted groundwater downgradient of the existing landfill facility. The following scope of work is proposed to achieve the above referenced objective: • Drill one soil boring to 105 feet below site grade (BSG) and collect soil samples for lithology purposes; • Complete the boring as a two-inch diameter groundwater monitoring well; • Develop the well and install a dedicated bladder pump. The dedicated pump will be removed from the existing well (MW -14), cleaned, additional tubing added, and the pump will be installed in the replacement well. • Prepare a summary report documenting field activities. The Austin Road Landfill (site), a municipal waste collection center, is located southeast of the City of Stockton, California immediately west of the intersection of St. Johns Creek and Austin Road (Drawing 1). 3.1 Geologic and Hydrologic Characteristics 3.1.1 Geolo The site is located in the northern portion of the San Joaquin Valley which comprises the southern segment of the larger Great Valley. The Great Valley is an asymmetrical synclinal trough interrupted by two major surface cross structures: the Stockton fault in the Stockton arch and the White Wolf fault in and south of the Bakersfield arch. The Stockton fault is located approximately five miles northwest of the site, trending northeast. The Great Valley has been filled with a sequence of older to younger alluvium of Pliocene to Holocene age which overlie sedimentary rocks of Cretaceous to Tertiary age. These sedimentary units, in turn, overlie a crystalline basement of Paleozoic and Mesozoic metamorphic and igneous rocks. The shallow subsurface geology in the site vicinity consists of a heterogeneous mix of gravel, sand, silt, and clay (Norris and Webb, 1990).