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<br /> 4. Stratus prepared and submitted a Remedial Action Plan (RAP) (July 1, 2003) proposing soil
<br /> vapor extraction for onsite treatment of impacted soil and isolated perched groundwater.
<br /> WORK PROPOSED FOR NEXT QUARTER (Third 2003):
<br /> 1. Stratus will continue to remove floating product from well MW-1 on a weekly basis, monitor free
<br /> product thickness in selected wells, and remove floating product when necessary.
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<br /> 2. The next sampling event is tentatively scheduled for September 2003. Groundwater samples will
<br /> be analyzed for total petroleum hydrocarbons as gasoline (TPHG), benzene, toluene,
<br /> ethylbenzene, total xylenes (BTEX), tertiary butyl alcohol (TBA), methyl tertiary butyl ether
<br />' (MTBE), di-isopropyl ether (DIPE), ethyl tertiary butyl ether (ETBE), tertiary amyl methyl ether
<br /> (TAME), and ethanol using USEPA Method 82606.
<br /> 3. Upon approval of the previously submitted Work Plan, Stratus will implement efforts to obtain
<br /> offsite access in order to implement the proposed assessment activities.
<br /> 4. Upon approval of the RAP, Stratus will initiate onsite activities leading to the final installation and
<br /> startup of the soil vapor extraction system.
<br /> DISCUSSION f
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<br /> During quarterly monitoring activities on June 16, 2003, floating product was observed in well MW-1.
<br /> During the weekly visits to the site, product was measured in well MW-1 at thicknesses ranging from a I
<br /> �-� sheen to 0.10 feet thick, in well VW-4 between a sheen and 0.21 feet thick, and in well VW-1 between a
<br /> sheen and 0.07 feet thick. During each site visit, free product in the wells was manually bailed, and
<br /> placed in properly labeled DOT-approved drums pending disposal. Approximately 17.25 gallons of a
<br /> mixture comprising of free product and water was bailed from wells MW-1, VW-1, and VW-4 during the
<br /> second quarter 2003. Approximately 127 gallons of product/water mixture have been bailed to date.
<br /> Product thickness measurements and volumes of liquid bailed are summarized in Table 1.
<br /> In wells MW-3, MW-5, MW-6, MW-8, MW-9, VW-1, VW-7, VW-8, VW-10, VW-13, VW-14, VW-18, and
<br /> VW-20, there was an average of<0.25 feet of water column in the well; the water in these wells does not
<br /> appear to be formation water. Wells MW-4, MW-7, VW-2, VW-3, VW-4, VW-9, VW-11, VW-12, VW-16,
<br /> VW-17, and VW-19 were dry. Well VW-15 was inaccessible (dirt in casing). Groundwater in wells
<br /> screened within the upper water-bearing zone (MW-2, VW-5, and VW-6) was measured at depths
<br /> between 38.68 and 59.39 feet below bgs, approximately 0.06 to 0.08 higher and 2.58 feet lower than
<br /> groundwater elevations measured during the first quarter 2003. Groundwater in well MW-1 (screened in
<br /> the lower water-bearing zone) was measured at 105.02 feet bgs, 0.18 feet higher than the groundwater
<br /> measured during the first quarter 2003 event. These data are similar to groundwater data from previous
<br /> quarters. Groundwater measurements are summarized in Table 2. Groundwater elevations are included
<br /> in Figure 2. Wells that contained a small amount of water but are interpreted to be dry are indicated as !
<br /> dry on Figure 2.
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<br /> During the second quarter 2003 sampling event, TPHG was reported in wells MW-2, MW-6, VW-5,
<br /> VW-6, and VW-20 with the highest concentration (63,000 4g/L) reported in well VW-20. Benzene was
<br /> reported in wells MW-6, VW-5, VW-6, and VW-20 with the highest concentration (13,000 pg/L) reported
<br /> IG in well VW-20. MTBE was reported in wells MW-6 and VW-6 with the highest concentration (170 pg/L)
<br /> reported in well VW-6. Other than MTBE, fuel oxygenates were not detected in any of the wells. I
<br /> Petroleum hydrocarbons or fuel oxygenates were not detected in the domestic well. These data are
<br /> similar to chemical analytical data from previous quarters. TPHG, benzene, and MTBE analytical data
<br /> ~ for the samples collected on June 16 and 17, 2003, are presented in Figure 3.
<br /> PA1Bp-Arco for URS161001Quarlerly120031Arco_6100_2Q03,doe 57-RATUS
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