ARCHIVED REPORTS XR0000111 - Laserfiche WebLink

Home Browse Search

Page 2 Ms Margaret Lagono ' June 24, 1996 ' A 20,000-gallon diesel-fuel tank, was located beneath the parking lot on the east side of the facility (see Figure 2) t The gasoline tanks near the southwest building corner were removed in April 1987 The westernmost gasoline tank failed a tank integrity test in December 1986 The easternmost gasoline tank had previously been abandoned in place, prior to 1986, by removing the fuel ' and filling the tank with sand The two diesel-fuel USTs were removed in September 1989 ' Approximately 450 cubic yards of soil was excavated during removal of the two USTs in 1987, of which approximately 120 cubic yards were impacted by gasoline The soil was disposed of onsite with guidance from the San Joaquin Air Pollution Control District In July and September 1987, Environmental Science and Engineering, Inc installed three groundwater monitoring wells (MW-1 through MW-3) In January 1988, Anderson Consulting Group (ACG) installed wells MW-4 and MW-5 ACG installed wells MW-6 ' and MW-7 in February 1990, and MW-8 in September 1990 In March 1994, Philip (formerly Burlington Environmental) installed wells MW-9 through MW-13 in five boreholes that were drilled at the facility Soil samples were collected from the boreholes for chemical analysts Soil sample hydrocarbon concentrations were all below laboratory method detection limits with the exception of the 60-foot depth sample from borehole MW-13, which contained 10 micrograms per kilogram (pg/kg) of benzene ' This sample was collected at a depth just below the groundwater table, and was probably contaminated by hydrocarbon-impacted groundwater at that location ' Groundwater samples were also collected and analyzed The concentrations of total volatile hydrocarbons as gasoline (TVH-G) in the groundwater samples ranged from below laboratory method detection limits to 69,000 micrograms per liter (pg/L) Benzene concentrations in the groundwater samples ranged from below laboratory method ' detection limits to 2,000 pg/L Phase-separated hydrocarbons (PSH) have not been detected in any of the facility wells ' Philip has submitted a Remediation System Pilot Test Workplan, dated July 1, 1994, to the San Joaquin County Environmental Health Division describing proposed groundwater cleanup technologies These technologies include groundwater sparging combined with soil venting Several sparge and vent wells have been installed to implement this ' remediation However, cleanup has been postponed due to pending changes in related California remediation guidelines Philip will continue groundwater monitoring until at least those changes have been established 1 E ICTI10212QTR96 DOC