ARCHIVED REPORTS XR0001845 - Laserfiche WebLink

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Geological Audit Services (1991) made the following conclusions (1)that offsite migration of petroleum hydrocarbons released from the site was a possibility, (2)the horizontal extent of soil and/or groundwater petroleum hydrocarbon contamination was not yet determined, (3) the water bearing unit at 40 feet bgs should allow recovery of the free product and/or dissolved contamination from the first water-bearing zone, (4) that a more northerly source may be contributing to the identified petroleum hydrocarbon groundwater contamination,and(5) that 3,000 to 4,000 gallons of gasoline were potentially present in the groundwater immediately beneath the site Based on the conclusions reached by GAS (1991), Falcon Energy reportedly extracted and removed several thousand gallons of petroleum hydrocarbon impacted groundwater In January 1994,PHSEHD directed that the three monitoring wells be sampled to assess current groundwater conditions beneath the site Mr Dana Booth,Consulting Geologist was retained by the property owner,Mrs Yearing, to conduct the work Mr Booth supervised the resurveying,redevelopment of monitoring wells, and water sample collection of each of the three existing monitoring wells On March 7, 1994 the following groundwater conditions were reported by Booth(1994)to exist at the site (1) A product layer of 0 03 foot thickness was measured at PT-MW-3, (2) The water samples from PT-MW-1 and PT-MW-2 reportedly contained TPH-g and BTEX concentrations significantly above established Maximum Contaminant Levels(MCL's), (3) The groundwater gradient was calculated at 0 003 toward the southwest(using a 0 8 relative density for the product layer) Two water samples were reportedly collected(PT-MW-1 and MW-2)and transported to West Laboratories, Davis,California under chain of custody documentation The water samples were analyzed using USEPA Test Method 602 for benzene,toluene, ethylbenzene, and xylene and 8015M for TPH-gasoline Analytical reports for these two water samples were reported to contain maximum concentrations as follow TPH-gas(23,000 µg/1), benzene(2,000 µg/1), toluene(3,500 µg/1), ethylbenzene(2,800 µg/1), and xylene (2,800 µg/l) No water sample was reportedly collected from monitoring well PT-MW-3 . MamlD 1EnwonmenW\Parn=Texaco\Repws\SARI203 wpd Page 8