WORK PLANS - Laserfiche WebLink

Home Browse Search

Appendix B Advanced AGE Project No. 99-0559 Environmental Page 7 of 12 n.M 9 OFF-SITE CPT LITHOLOGIC INVESTIGATION: SEPTEMBER AND OCTOBER 2002 Five paired borings (CPT-4 to CPT-8) were advanced off-site utilizing CPT technology to model the geological and hydrogeological framework and to assess the lateral and locally the vertical extent of dissolved petroleum-hydrocarbons off the site. Lithologic data was collected from an initial CPT soil boring at each boring location, a twin boring was then advanced immediately adjacent to the initial CPT soil boring to collect grab groundwater samples from selected depths. Soil borings were advanced vertically to the following total depths at the specified locations. A site plan depicting boring locations is presented in Figure 2: CPT-4 was advanced to 118 feet below surface grade (bsg) at the northern edge of the Waterloo Road sidewalk, west of the site; CPT-5 was advanced to 125 feet bsg on the eastern edge of Golden Gate Avenue, approximately 150 feet south of Waterloo Road; CPT-6 was advanced to 165 feet bsg on the western edge of Chronicle Avenue, approximately 250 feet south of Waterloo Road; CPT-7 was advanced to 145 feet bsg on the western edge of Sutro Avenue, approximately 100 feet north of Waterloo Road; and CPT-8 was advanced to 168 feet bsg on the western edge of Golden Gate Avenue, at Waterloo Road. Groundwater sample was collected from the CPT borings at the following intervals: • CPT-4 was sampled at 70 feet (HU3), 90 feet (HU4), 125 feet bsg (HU5U); • CPT-5 was sampled at 70 feet (HU3) 100 feet (HU4) and 150 feet bsg (HUSL); • CPT-6 was sampled at 70 feet (HU3), 100 feet (HU4), 125 feet (HU5U) and 150 feet bsg (HUSL); • CPT-7 was sampled at 70 fee (HU3) t, 100 feet (HU4) and 130 feet bsg (HU5U); and • CPT-8 was sampled at 70 feet (HU3), 100 feet (HU4), 125 feet (HU5U) and 165 feet bsg (HU5L/HU6). ANALYTICAL RESULTS OF GROUNDWATER SAMPLES: OCTOBER 2002 A total of nineteen discrete, groundwater samples was collected from HU2, HU4, Upper HU5 and Lower HU5 and submitted for laboratory analysis. HU2 Samples CPT4-70, CPT5-70, CPT6-70, CPT7-70 and CPT8-70 were collected from HU2, the upper most occurrence of groundwater from the CPTs. TPH-g was detected only in samples CPT4-70 and CPT8-70 at concentrations of 1,100 micrograms per liter(pg/1) and 150 pg/l, respectively. The BTEX compounds toluene and xylenes were detected in sample CPT8-70 at concentrations of 1.4 pg/I and 1.1 pg/l, respectively. The fuel additive MTBE was detected in CPT4-70, CPT6-70 and CPT8-70 at a maximum concentration of 1,500 pg/I (CPT4-70); ETBE were detected in CPT4-70 and CPT8-70 at a maximum concentration of 3.4 pg/I (CPT4-70); and 1,2-DCA was detected in CPT8-70 at 6.2 pg/l.