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<br /> (THP@S-15) TPHg, TPH-O, toluene, ethyl benzene, and total xylenes were not detected above
<br /> laboratory detection limits Laboratory analysis of groundwater samples from borings THP-1 and
<br /> THP-2 detected maximum concentrations of TPHg at 6,900 ppb (THP2W-21), TPHd at 840 ppb
<br /> (THP2W-21), benzene at 1,900 ppb (THP2W-21), and total xylenes at 77 ppb(THP2W-21) TPH-O,
<br /> benzene toluene, ethylbenzene, and Halogenated Volatile Organic Compounds (HVOC's) were not
<br /> detected above laboratory detection limits (EMCON, 1994)
<br /> On December 10 through 22, 1998, Gettler-Ryan Incorporated (GR) supervised the removal of two
<br /> 10,000 gallon and one 8,000 gallon single-walled UST, dispensers, and associated product
<br /> dispenser piping Laboratory analysis of soil samples collected from the UST excavation detected
<br /> maximum concentrations of TPHg at 31 ppm (3W), benzene at 0 27 ppm (3W), and Methyl-tert Butyl
<br /> Ether(MtBE) at 80 ppm (3E) Laboratory analysis of soil samples collected from the beneath the
<br /> dispensers and product piping detected maximum concentrations of TPHg at 1,600 ppm (131) and
<br /> MtBE at 1 8 ppm (D3) Additionally, approximately 15,000 gallons of water was removed from the
<br /> UST excavation during the installation of the new USTs Laboratory analysis of a grab groundwater
<br /> sample detected maximum concentrations of TPHg, benzene, and MtBE at 17,000 µg/L, 1,500 µg/L,
<br /> and 120,000 gg/L, respectively Groundwater Monitoring Well MW-1 was destroyed to allow the
<br /> enlargement of the existing UST excavation to allow for the installation of the new USTs (GR, 1999)
<br /> On October 7 and 8, 1999, Cambria Environmental Technology, Incorporated (Cambria) conducted
<br /> Cone Penetration Testing (CPT) by advancing six borings (CB-1 through CB-6) for soil and
<br /> groundwater sampling and two borings (CB-2E and CB-4E)for electric soil logging Soil samples
<br /> were collected every five feet to approximately 20 feet bgs Water samples were collected using a
<br /> hydropunch at depths of 16 and 29 feet bgs in borings CB-1, CB-2, and CB-4 through CB-6 Water
<br /> samples were collected at depths of 16 and 29 feet bgs in boring CB-3 Laboratory analysis of soil
<br /> samples collected from the soil borings detected maximum concentrations of gasoline range
<br /> organics (GRO) at 27 milligrams per kilogram (mg/kg) (CB-3-13 5), MtBE at 27 mg/kg (CB-3-13 5),
<br /> and Tert amyl methyl ether (TAME) at 0 058 mg/kg (CB-3-13 5) BTEX was not detected above K
<br /> laboratory detection limits Laboratory analysis of groundwater samples collected from the soil
<br /> borings detected maximum concentrations of gasoline range organics(GRO) at 87,000 Ag/L (CB-4-
<br /> 16HP), benzene at 1,300 gg/L (CB-4-16HP), MtBE at 38,000 µg/l_ (CB-1-16HP), and TAME at 160
<br /> gg/L (CB-1-16HP) (Cambria, 1999)
<br /> On June 12 and 13, 2000, Cambria replaced destroyed Well MW-1 and damaged Well MW-2 with
<br /> Groundwater Monitoring Wells MW-1 R and MW-2R to depths of 31 5 and 30 feet bgs, respectively
<br /> In addition, Cambria drilled and installed two 2-inch diameter wells (MW-9 and MW-10) to a total
<br /> depth of 31 5 feet bgs Laboratory analysis of soil samples collected from the soil borings detected
<br /> maximum concentrations of TPHg at 0 82 mg/kg (MW8-12') and MtBE at 2 6 mg/kg (MW8-30)
<br /> BTEX was not detected above laboratory detection limits Laboratory analysis of groundwater
<br /> samples collected from all wells detected maximum concentrations of TPHg at 3,400 Ag/L (VW-1),
<br /> benzene at 84µg/L (VW-1), MtBE at 250,000 µg/L, and Tert-butyl Alcohol (TBA) at 17,000 84µg/L
<br /> (MW-2R) (Cambria, 2000)
<br /> Groundwater monitoring and sampling was initiated in 1992 and are currently sampled quarterly
<br /> Depth to groundwater at the site as ranged from 11 to 18 feet bgs In August 2000, an interim
<br /> migration control plan at the site was initiated to reduce the amount of petroleum hydrocarbons and
<br /> MtBE beneath the site, and to prevent further off-site migration of the dissolved plume The plan
<br /> consisted of the periodic extraction of approximately 5,000 gallons of impacted groundwater from
<br /> wells historically containing the highest concentrations of petroleum hydrocarbons and MtBE (MW-
<br /> 1 R, MW-2R, and VW-1) Remedial extractions continued during the third quarter with a total
<br /> extraction 868,000 gallons to date
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