Laserfiche WebLink
i <br /> SOIL BORINGS, NOVEMBER 28, 1994 <br /> Selection of _Soil Boring Locations <br /> On November 28, 1994 , a total of three soil borings were drilled on <br /> the Lopez property, SBA for Ms. Pam Lopez and SB3 and SB4 for TVG. <br /> TVG drilled SB3 to the north east of their former tank excavation. <br /> The soil from this boring field tested as clean, establishing the <br /> northern edge of the soil plume. <br /> While the rig was on site to drill the Tri--Valley boring, it was <br /> also used to drill SBA for Ms. Lopez . Because of the possibility <br /> of cross contamination resulting from the neighboring TVG plume, <br /> SBA was drilled on the location of the former Lopez property tank. <br /> The PID readings and product odor present in this SBA indicated <br /> that the former tank area was contaminated. In order to establish <br /> if this problem originated from the former tank or was part of the <br /> TVG plume, TVG drilled SB4 between the former Lopez tank pit and <br /> the TVG tank excavation. The concentrations observed in SB4 were <br /> much lower than SSA indicating that the Lopez property <br /> contamination is a separate plume from the TVG plume. <br /> The locations of the borings are shown in Figure 3 . <br /> Drilling and Soil Sample Collection <br /> The soil borings were drilled by a licensed drilling contractor <br /> using a mobile rig equipped with eight inch diameter hollow stem <br /> augers. The borings were drilled to 20 feet. Representative soil <br /> samples were collected at five foot intervals, in 2" X 6" brass <br /> sleeves, with the aid of a 140 lb. slide hammer and split spoon <br /> sampler. A new disposable bailer was used to collect a water <br /> sample from the inside of the augers. <br /> The augers and sampling equipment were steam cleaned prior to the <br /> drilling of each soil boring and the sampling equipment washed with <br /> a TSP solution between each sampling interval . <br /> During the drilling operations, the geologist maintained a log of <br /> the materials encountered. Soil samples were field screened for <br /> the presence of total volatile organic (TVO) vapors using a <br /> handheld PID equipped with a 10. 2 EV lamp. <br />• <br /> 2 <br />