ARCHIVED REPORTS_XR0004492 - Laserfiche WebLink

Home Browse Search

>I savou athmpk00ame Octobw 4 1945 Pop-Z i • were collected Laboratory analyses detected 6 2 gg/kg toluene and 10 pg/kg xylene in the sample collected from the floor of the over-excavation at 15 5 feet below ground surface (bgs) Hydrocarbon contamination was not detected at or above the reported laboratory detection hrruts in the two samples collected from the east sidewall of the over-excavation At the direction of San Joaquin County Public Health Services, Environmental Health Division (SJCPHS,EHD), one monitor well (MW 1) was installed at the Di Salvo Lathrop site in June, 1995 MW 1 was installed Iin the estimated down gradient direction approximately 10 feet northwest of the former east end of TK4 On August 14 1995 Condor installed a groundwater pumping system designed d for short- term, continuous operation in well MW 1 On August 22, 1995, following removal of approximately 15,700-gallons of groundwater from MW 1, the system was turned off and one groundwater sample was collected from MW 1 Laboratory analyses of a groundwater sample indicated no evidence of hydrocarbon constituents at or above the reported laboratory detection hnuts SJCPHS,EHD recommended in written correspondence dated September 22, 1995, (attached) that a confirmation groundwater sample be collected from MW 1 approximately 3 0 days from August 22, 1995 SJCPHS,EHD also stated in their correspondence that of the confirmation groundwater sample from MW 1 indicated no evidence of hydrocarbon contamination, that SJCPHS,EHD will direct Di Salvo Trucking to decommission MW 1 I Following decommnssnomng ofMWl, SJCPHS,EHD indicated a closure letter would be issued for the Di Salvo Lathrop site GROUNDWATER SAMPLING On September 25, 1995, a groundwater sample was collected from MW1 The groundwater sample was collected in accordance to Condor's Work Plan for Modified Groundwater Sampling, dated July 25, 1995, and approved by SJCPHS,EHD Prior to sample collection, the static water level in MW1 was measured to the nearest 0 01-foot with a battery- operated, flat-tape, water-level meter The water level measurement indicated the depth to igroundwater was at least 80% of the pre-purge measurement The groundwater sample was collected with a new, disposable bailer The groundwater sample was transferred to 40-m1 glass VOA vials fitted with Teflon-lined caps and 1-Inter glass bottles Each vial was inverted and tapped to assure that no air bubbles were present The sample containers were labeled, placed in a cooler chilled with Blue Ice, and delivered under chain-of-custody procedures to GeoAnalytfcal Laboratories, Inc , in Modesto, California, within 24 hours of sample collection The sample was analyzed for benzene, toluene, ethyl benzene, and xylene (BTEX) by EPA Method 602 and for �� CONDOR