Laserfiche WebLink
The impacted soil was excavated using a backhoe with an extended boom. During the <br /> excavation activities, the soil was initially screened for the presence of petroleum <br /> hydrocarbons using a photononization detector (PID). The initial plan was to use the PID <br /> readings to segregate the soils. Based upon PID readings obtained, all soils were stockpiled <br /> together for disposal. The soil was excavated to the maximum extent practical, based on the <br /> location of the underground utility to the south, monitoring well MW-4 to the north, and the <br /> physical limits of the available equipment. Showing or sloping of the excavation was not <br /> required due to the tight nature of the native soil. Appendix A contains selected photographs <br /> of excavation activities <br /> The excavated material was stockpiled adjacent to the excavation on plastic sheeting and was <br /> covered with secured plastic sheeting at the end of each shift to prevent uncontrolled <br /> petroleum vapor emissions <br /> 2.3.2 So#Sampling and Characterization <br /> Soil samples were collected during field activities in order to assist in determining the extent <br /> (if any) of impacted soil surrounding the previously removed underground storage tanks <br /> (USTs) Discrete soil samples were collected from the sidewalls and the floor of the <br /> excavation, under the direction of the County REHS In addition, composnted soil samples <br /> were collected from the stockpiled soil in order to profile the soil prior to disposal (Figure 3) <br /> Soil samples were collected in 2" x 6" pre-cleaned brass sleeves. The samples were <br />' described, screened for the presence of hydrocarbons and promptly sealed with aluminum foil <br /> and plastic end caps. The samples were individually placed in "znplock" bags, sealed with <br /> security tape and stored in an ice chest with water ice at approximately 4'C until hand <br /> delivery to the selected laboratory for analysis Chain-of-custody records were maintained for <br />' all samples (Appendix B). <br /> The soil samples collected from the excavation were analyzed for TPH as gasoline and TPH <br /> as diesel using the modified EPA method 8015 and BTEX using EPA method 8020. In <br /> addition to being analyzed for the target compounds listed above, the stockpile profile <br /> samples were analyzed for total lead by EPA method 6010. The samples were analyzed by <br /> Sparger Technology, Inc., a California State Department of Health Services certified <br /> MWO&23/95rv11)BFJ95-oom 4 <br />