ARCHIVED REPORTS XR0000155 - Laserfiche WebLink

Home Browse Search

Ife' raviounc- SACRAMENTO ' The site specific geology, as based on the data obtained during the drilling of the boreholes at the site, is as follows: ' from 0 to 12 feet below ground surface (bgs) is a brown, very silty sand, which is underlain by a light brown, sandy, very clay--rich silt to a depth of approximately 18 feet bgs. A medium brown, clay-rich, very sandy silt extends to depths ranging from 24 feet to 32 feet bgs. The sandy silt is underlain by a light ' brown, sandy, very salty clay. The deepest borehole terminated in a gray-brown, silty clay silt at 45 feet bgs. ' 2 . 3 Surface Water and Geohydrology The site is situated within the San Joaquin River Basin (Basin 5C) as designated by the Central Valley Regional Water Quality Control Board (RWQCB) (Region 5) . The nearest surface ' water to the Pacific Bell facility is the Calaveras River, which flows in a westward direction and is located approximately 100 yards south of the site. Ground water is reportedly present at a depth of greater than 60 feet bgs. The ground-water flow ' direction is reportedly to the west. Ground water was not encountered at any time during the UST removal , site investigation or pilot study. ' 2 . 4 Beneficial Uses of Water The Water Quality Control Plan (Basin Plan) for the San Joaquin River Basin lists the beneficial uses of ground water within San Joaquin County as municipal and domestic water supply, irrigation, stock watering and service supply (RWQCB, 1990) . Ground water is known to be used for agricultural purposes throughout the rural area surrounding the site. The nearest ground-water well is located 50 feet south of the tank excavation ' site and is used by Pacific Bell in their facility operations. The well is reportedly 150 feet deep and draws water from an aquifer at approximately 135 feet bgs. 5