SU0004287 SSNL - Laserfiche WebLink

Home Browse Search

KLEINFELDER We do not know of any existing and/or potential groundwater contamination issues in the project vicinity. There are no existing gas stations or dairies adjacent to the property. We anticipate that septic system usage and landscape fertilization, if any, would be the primary future on- and off- site sources of nitrogen to soil and groundwater. On September 9, 2003, a representative with our firm obtained samples of groundwater from the property using clean procedures from an exterior faucet on the west wall of the building east of the well. The samples were immediately placed in a chilled cooler, transported to our office, and stored in a refrigerator until they were picked up the same day by Sequoia Analytical using chain-of-custody procedures for DBCP and nitrate (N) testing. The results of the tests and a copy of the chain-of-custody are attached. Groundwater at the site is currently used predominantly for uses incidental to an office environment. We anticipate that the predominant use for Rogers Trucking would be residential uses for the trailer occupant. SOIL PROFILE The subsurface conditions at the site were explored at about 7:30 am on September 9, 2003, by drilling one boring to a depth of approximately 17'/2 feet below existing grade. The boring was drilled using a Simco 2400 truck-mounted drill rig equipped with 6-inch O.D. solid-stem auger. The approximate boring/percolation test location and approximate dimensions from reference points are presented on the site plan. Based on our findings, the subsurface soils encountered consisted predominately of silty clay to a depth of about 3 feet below the existing site grade, underlain by interbedded silt and clay strata to a depth of approximately 16`/2 feet. At that depth, a silty sand stratum was encountered which extended to the maximum depth explored. A more-detailed description of the subsurface conditions encountered during our field investigation is presented on the attached Log of Boring. In general, the low-permeable, near-surface clay and silt in the project area does not yield percolation rates passing SJCEHD percolation requirements for a shallow test. The Soil Survey of San Joaquin County, California published by the US Department of Agriculture, Soil Conservation Service (1992) refers to the near-surface soils within the project area as belonging to the Jacktone-Urban land complex (Map Symbol 181). The soils are described as having severe percolation characteristics (cemented pan, peres slowly), an available water capacity of 0.14 to 0.16 inches per inch, a pH ranging from 6.8 to 8.4, and an organic content of 2 to 5 percent. PERCOLATION TESTING The 6-inch diameter percolation holes were drilled with the same equipment as the soil profile boring. One percolation hole (in addition to the profile hole)was drilled on the subject property. The holes had scored sides and no significant loose material in the bottom of the hole. Both holes were drilled and prepared before 8:00 am on September 9, 2003. The preparation 35228.GO1/STO3R1508 October 14,2003 O 2003 Kleinfelder, Inc. Page 3 of 6