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the northern portion of the site. The North Creek was successfully relocated from its original location (south of the former Austin Road Landfill which is now part of FL) to the northern boundary of the FL in 2001/2002. 2.3 GEOLOGY AND SEISMICITY 2.3.1 REGIONAL GEOLOGY The Forward Landfill is located in the central portion of the Great Valley geomorphic province in the region locally referred to as the northern San Joaquin Valley. The Great Valley is an elongated asymmetrical structural trough bounded on the east by the Sierra Nevada and on the west by the Coastal Range. In the northern San Joaquin Valley, nearly 8,000 feet of sediments have accumulated within the basin, including an accumulation of about 5,250 feet of marine clays, silts, and sands subsequently overlain by approximately 2,500 feet of unconsolidated terrestrial sediments. The uppermost portion includes the Pleistocene age Victor Formation. In the northern San Joaquin Valley, this unit includes about 100 feet of laterally and vertically discontinuous fine grained clays and silts with interbedded coarser-grained sediments characteristic of meandering fluvial deposition. 2.3.2 SITE GEOLOGY The geology and hydrogeology of FL have been detailed in several reports including Kleinfelder & Associates (1991, 1997, 1999), CH2MHill (1992) Beta Associates (1988), EMCON Associates (1972), and GLA (2007). These studies confirm that the geology, as well as the hydrogeology of the FL, are consistent with regional conditions. The uppermost sediments of the Victor Formation have been divided into three subunits based on lithologic logs for boring and monitoring wells that identified logical groupings of gross lithology and pervasive color distinctions. The upper 28 to 40 feet consist of highly interbedded sandy silt, clayey silt, silt, and clay. Most of these sediments have an oxidized appearance and an orange brown color. Below this subunit is a 25-to 35-foot thick, gray- brown interbedded sand, silty sand, and minor clay subunit. The third subunit occurs to a depth of about 110 feet and is generally light brown to yellow brown dominated by fine to medium-grained sand, with some coarse-grained sand and gravelly layers and a Forward Landfill-Project Description 2-3 BRYAN A.STIRRAT&ASSOCIATES j:\Allied\Forward\2007.0018 Lateral Expansion\Reports\Prof Descrip\021308 Final Proj Des\Sec 2.doc:2/13/2008)