WORK PLANS - Laserfiche WebLink

Home Browse Search

Attorney-Client Privileged 4. TOPOGRAPHY, GEOLOGY, AND GROUNDWATER Topography of the area is characterized by relatively flat land with a slight southwesterly elevation relief. According to the U.S. Geological Survey (USGS) 7.5-minute series topographic map (see Appendix E) of the City of Stockton West Quadrangle (1987), the subject property is located at an average ground elevation of approximately 27 feet above mean sea level (msl). There are no surface waters on the subject property. The closest surface water to the property is the Morman Slough, which is approximately 2 miles from the subject property). The site is located on the Great Valley Geomorphic province of California. The valley is comprised of thick marine and non-marine formations from the late Jurassic to late Holocene. The upper most strata of the g-Great v Valley is are primarily comprised of alluvial, flood, and delta plains of the two major rivers (Sacramento and San Joaquin Rivers) and their tributaries. The project area is underlain by unconsolidated alluvial deposits. The soil encountered in the subsurface includes clay, silt, sand and gravel, however, the predominant soils are interbedded sandy clay and silty sand. Groundwater at this site, under normal conditions, as documented by CH2M Hill's March 2002 historical ground water monitoring is approximately -53 feet below ground surface (bgs) with a Northeasterly gradient in 1991. The groundwater level, however, has, risen 33 feet to its present elevation due to the cessation of pumping from three production wells and other municipal well pumping in the area. According to the San Joaquin County Flood and Water Conservation District (Spring 2003) and historical ground water monitoring by CH2MHILL and Kelinfelder (Kleinfelder, 4th quarterly ground water monitoring report of 2007 for the Former Disco Facility) in the Page 3 of 21