ARCHIVED REPORTS_XR0011827 - Laserfiche WebLink

Home Browse Search

i WORK PROPOSED FOR NEXT QUARTER (Fourth, 2002) 1 Stratus will continue to remove floating product from well MW-1 on a weekly basis, monitor free product thickness in selected wells, and remove floating product when necessary I 2 Stratus will continue to monitor depth-to-water in selected vapor extraction and monitoring wells 3 Stratus will sample select vapor extraction and monitoring wells The onsite water supply well will also be sampled The next sampling event is tentatively scheduled for December 2002 Groundwater samples will be analyzed for total petroleum hydrocarbons as gasoline (TPHG), benzene, toluene, ethylbenzene, and total xylenes (BTEX) by USEPA Method 8015/8020 DHS LUFT, and for tertiary butyl alcohol (TBA), methyl tertiary butyl ether (MTBE), di-isopropyl ether (DIPE), ethyl tertiary butyl ether (ETBE), tertiary amyl methyl ether (TAME), and 1,2-dichloroethane (1,2-DCA) using USEPA Method 82606 4 Upon approval of the previously submitted Work Plan, Stratus will implement offsite access in order to implement the proposed assessment activities DISCUSSION During quarterly monitoring activities on September 18, 2002, free product was observed in well MW-1 at a thickness of 0 28 feet During the weekly visits to the site, product was measured in well MW-1 at thicknesses ranging from 0 22 to 0 41 feet thick During each site visit, free product in the well was manually bailed, and placed in properly labeled DOT-approved drums pending disposal Approximately 3 5 gallons of free product was bailed from well MW-1 during the third quarter 2002, and 59 gallons of free product have been bailed to date During the third quarter 2002 sampling event, TPHG, BTEX, and MTBE were detected in the groundwater samples collected from wells VW-4 and VW-6 The highest concentrations of TPHG (160,000 pg/L), benzene (21,000 pg/L), and MTBE (1,200 pg/L) were detected in well VW-4 TBA was detected in groundwater samples collected from wells MW-2 (6 6 pg/L) and VW-6 (270 pg/L ) Other fuel oxygenates were not detected in any of the wells Petroleum hydrocarbons or fuel oxygenates were not detected in the sample collected from the domestic well This data is similar to chemical analytical data from previous quarters In wells MW-3, VW-1, VW-3, VW-5, and VW-14 there was less than 1 foot of water column in the well, the water in these wells does not appear to be formation water, therefore the wells were not sampled Wells MW-2 through MW-9, VW-2, VW-7 through VW-13, and VW-15 through VW-20 were dry The groundwater in wells screened within the upper water-bearing zone (MW-2, VW-4, and VW-6) were measured at depths between 34 50 and 59 35 feet below top of well casing (TOC) Groundwater in well MW-1 (screened in the lower water-bearing zone) was measured at 105 65 feet below TOC This data is similar to groundwater data from previous quarters i P 18p-Arco for URS161001Quartcrly120021Arco_6100_3Q02 doc 5rRAW5