Laserfiche WebLink
31 January 2013 <br />AGE-NC Project No. 02-0926 <br />Page 3 of 21 <br />680,000 pg/I benzene, 1,500,000 pg/I toluene, 420,000 pg/I ethylbenzene and <br />3,280,000 pg/I total xylenes. <br />January and February 2004 - Three groundwater monitoring wells (MW-1 through <br />MW-3) were installed at the site. A total of seventeen soil samples were collected <br />during the investigation. Petroleum hydrocarbons were not detected at or above <br />laboratory reporting limits in the soil samples collected from monitoring well borings. <br />August 2005 - Three cone penetration testing (CPT) soil borings (CPT-1 through <br />CPT-3) were advanced on- and off-site. A total of six grab groundwater samples <br />were collected during the investigation. TPH-g were detected in one of the six <br />groundwater samples (CPT3-68-72) at a concentration of 160 pg/I. One or more <br />BTEX compound was detected in two of the six samples (CPT3-68-72 and CPT3- <br />87-90) at maximum concentrations of 7.2 pg/I benzene, 6.7 pg/I toluene, and <br />9.0 pg/I total xylenes. During the investigation a total of two soil samples were <br />collected from boring CPT-3. Hydrocarbon constituents were not detected in the two <br />soil samples collected during the investigation. <br />June and August 2008 - Two groundwater monitoring wells (MW-5 and MW-6) and <br />two soil vapor wells (VW-1 and VW-2) were installed on-site near the former UST <br />location; one groundwater monitoring well (MW-4) was installed off-site in the City <br />of Stockton sidewalk approximately 180 feet south of the intersection of East Taylor <br />Street and Wilson Way Frontage Road. A total of thirty-three soil samples were <br />collected and analyzed from wells MW-5, MW-6, and VW-2; soil samples were not <br />collected from VW-1 and were not analyzed from well MW-4. TPH-g were detected <br />in a eighteen of the thirty-three samples at a maximum concentration of 3,900 <br />mg/kg (MW-5-15). TPH-d were detected in fourteen of the thirty-two soil samples <br />at a maximum concentration of 330 mg/kg (MW-5-15). BTEX compounds were <br />detected in eighteen of the thirty-three soil samples at maximum concentrations of <br />31 mg/kg benzene (MW-5-45), 230 mg/kg toluene (MW-5-45), 78 mg/kg <br />ethylbenzene (MW5-15) and 690 mg/kg total xylenes (MW-5-15). <br />Historical soil analytical results are summarized in Tables 1 and 2. Grab groundwater <br />sampling results are summarized in Table 3. A summary of well construction details is <br />included in Table 4. Boring logs are included in Appendix B. A site plan showing the <br />locations of all subsurface investigative boring locations are included in Figure 2. <br />3.0. HYDROLOGIC MODEL <br />A hydrogeologic, or hydrostratigraphic unit (HU) is defined as a body of rock or sediment <br />that has hydrogeologic characteristics (i.e. hydraulic conductivity, pore pressure, etc.) that <br />Advanced GeoEnvironmental, Inc.