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Conservation District, the regional groundwater in the vicinity of the site is now <br /> typically 20 to 30 feet below amsl (approximately 60 to 80 feet below ground <br /> surface) and flows to the north-northeast. <br /> Wells in the area are used primarily to supply water for agricultural and domestic <br /> purposes. Of the facilities in the area, the California Youth Authority and the <br /> Northern California Women's Facility north of the Forward Landfill both have <br /> wells that are thought to be used to supply drinking water. <br /> 3.7.2 LOCAL AQUIFERS <br /> The project area is underlain by sediments of the Victor formation, which consists <br /> of over 100 feet of clay, silt, and fine to coarse sand. The Victor formation is <br /> typically considered an unconfined aquifer, but locally exhibits a slightly confined <br /> condition associated with laterally discontinuous clay units. <br /> Near the Forward Landfill, groundwater ievels have dropped over the-fast°2010 30 <br /> years by approximately 10 feet due to agricultural pumping demand and drought <br /> (EMCON, 1972 and Kleinfelder, 1992). The groundwater level also fluctuates <br /> seasonally_by_approximately.5 to 10 feet due to a distinct rainy season and dry <br /> season. During the rainy season infiltration raises the water table and during the <br /> dry season drawdown bywaterwell users towers the water table. <br /> A minor perched water table at an elevation of about 20 feet above amsl was <br /> encountered while drilling one of the site wells. Perched water tables in the area <br /> are of a limited extent. <br /> 3.7.3 LOCAL WELLS <br /> The water used for dust control, compaction, and irrigation on the existing <br /> Forward Landfill is supplied by a well at the entrance. The well was drilled to a <br /> depth of approximately 135 feet and groundwater occurs at a depth of <br /> approximately 70 feet. The well was likely installed before the opening of the <br /> landfill, having been previously used for agricultural purposes. It is pumped at a <br /> rate of approximately 1500 gallons per minute at a maximum frequency of <br /> approximately eight times per hour. The fact that groundwater flow near the <br /> existing Forward Landfill is not modified by pumping from this well suggests that it <br /> is screened in a confined unit below the uppermost groundwater units that are <br /> Forward Landfill JTD 3-11 <br /> L:\Allied\2000.193\Reports\fi naljtd:Sec-3.0:08/20/01 <br /> BRYAN A.STIRRAT&ASSOCIATES <br />