COMPLIANCE INFO - Laserfiche WebLink

Home Browse Search

k'■ KLEINFELDER 4.0 RESULTS OF CHEMICAL ANALYSIS ITotal Purgeable Petroleum Hydrocarbons (TPPH) including BTEX were reported below the laboratory reporting limits from the five soil samples collected from within the excavation. A concentration of 45 mg/kg TPPH were detected in the four-point composite sample collected from the stockpiled soil. Three of the five soil samples collected within the soil excavation had reported concentrations ranging from 2.0 mg/kg to 3.2 mg/kg of Unidentified Extractable Hydrocarbons (C18-C38 range). The three soil samples with the reported concentrations were collected from the east, west and north sidewall of the excavation. The composite soil sample collected from the stockpiled soil had a reported concentration of 1,000 mg/kg Total Extractable Hydrocarbons within the diesel range. No other requested analytes for the six soil samples were reported at or above laboratory reporting limits For the excavation location refer to Plate 1. For the results of all the chemical analyses performed, please refer to the attached chain-of-custody records and laboratory data sheets (Appendix Q. 5.0 CONCLUSIONS AND RECOMMENDATIONS In September of 1997 a Phase I Environmental Assessment was conducted where "stained and odorous" soil were identified in the vicinity of a AGST. Chemical results of this soil indicated diesel fuel soil contamination of 57,000 mg/kg (ppm). On November 7, 1997 Kleinfelder observed the excavation of stained soil with a noted hydrocarbon-like odor in the vicinity of a former AGST. Three sidewall samples collected within this excavation had reported concentrations ranging from 2.0 mg/kg to 3.2 mg/kg Unidentified Extractable Hydrocarbons (C18-C38 range). No requested analytes were detected above laboratory reporting limits from a soil sample collected from the bottom of the excavation. Based on these results it is Kleinfelder's opinion that the sidewall soil concentrations are indicative of attenuation along the edge of the contaminant plume and therefore we recommend no further action relative to the excavation of soils beneath the former AGST. Kleinfelder recommends that a copy of this report be submitted to the PHS/EHD for their consideration. Kleinfelder has no control over the time frame for review and cannot accurately predict the outcome of county actions. 6.0 LIMITATIONS Kleinfelder has prepared this report in accordance with the generally accepted standards of care which exist in northern California at the time of writing. It should be recognized that definition and evaluation of geologic and chemical subsurface conditions are difficult. Judgments leading 20-2245-32.E01/2017R.720 Page 4 o[5 © 1997, Kleinfelder, Inc. November 18, 1997