FIELD DOCUMENTS - Laserfiche WebLink

Home Browse Search

2.0 ENVIRONMENTAL SETTING t Descriptions of the environmental characteristics and physical setting of the subject property are based upon a reconnaissance of the site and site vicinity;and review of readily available information. Topography The topography of the San Joaquin Valley is relatively flat sloping gently from the mountains to the east and west toward the San Joaquin River that lies more or less along the central axis of the valley. The terrain of the site vicinity is essentially flat sloping gently to the west toward the San Joaquin River. The US Geological Survey 7.5-minute Quadrangle Map with coverage of the site (Lodi North, California) depicted the subject property at an average elevation of about 55 feet above mean sea level (amsl). Natural elevation change across the site appears to be less the two feet. Geology and Soils ' San Joaquin County is located within the Great Valley physiographic province, which is a roughly 400- mile-long, northwest-southeast trending structural basin that extends through the central portion of ' California from the Tehachapi Mountains to the Klamath Mountains and ranges from 40 to 75 miles in width between the Coast Ranges and the Sierra Nevada Range. The Great Valley physiographic province is a structural trough filled with volcanogenic debris and pelagic sedimentary deposits that are up to 30,000 feet thick and dip relatively uniformly from each side of the valley toward its central axis. However, these deposits are generally a few thousand feet deep across the majority of the Great Valley. Three primary geologic units lie beneath San Joaquin County, including the metamorphic and igneous basement rock complex, unconsolidated marine sediments, continental deposits, and unconsolidated ' alluvium derived from fluvial systems originating from higher elevations to the east. The area about the subject property resides on recent alluvial, river channel, and floodplain deposits, which are underlain by the Quaternary Modesto, Riverbank, and Turlock Lake Formations and the Tertiary Mehrten Formation. ' Typical near surface sediments consists of poorly sorted sands and silty sands with interbedded silts, clayey sands, and clay. Typical thicknesses of near surface alluvial deposits generally range from 50 to 100 feet below ground surface(bgs). The Natural Resources Conservation Service (NRCS) has compiled soil survey data for San Joaquin County including areas about the subject property. The Soil Survey of San Joaquin County, California identifies soil at the subject property as Tokay-Urban Complex. The Tokay series consists of very deep, ' well drained soils formed in alluvium derived mainly from granitic rock sources. Tokay soils are on low fan terraces at elevations ranging from 10 to 150 feet amsl on slopes between 0 and 2 percent. These soils are well drained with slow runoff and moderately rapid permeability. Urban complex essentially refers to soils that have been re-worked and may be inclusive of non-native fill and engineered fill. Hydrology The subject property is located within the San Joaquin River drainage, which encompasses roughly 15,000 square miles of the San Joaquin Valley to the south of the Sacramento-San Joaquin River Delta and north of the Tulare Lake Basin. Principal tributaries to the San Joaquin River include the Consumnes ' River, Mokelumne River, Calaveras River, Stanislaus River, Tuolumne River, Merced River, Chowchilla River, and Fresno River. The subject property is situated about 13% miles south of the Mokelumne River, a tributary to the San Joaquin River that traverses westerly through the general area to the north of Lodi. The surface hydrology of the site and site vicinity has been altered by urban development. Surface water ' at the site would flow generally northwesterly and directed storm drains associated with the municipal storm water management system. ' Limited Subsurface Investigation (J&D Trust)J&D Auto Body 4 flUCrl� 1011 Cherokee Lane, Lodi, California