FIELD DOCUMENTS - Laserfiche WebLink

Home Browse Search

Mr. Sam Savig Page 2 of 3 peripheral to the area of concern and to remove contaminated soil while still accessible the following scope of work was conducted: Soil was excavated to a depth of approximately 9 feet below grade beneath the former dispenser. Approximately 5-6 cubic yards of soil were removed. The excavated soil was stockpiled on an impermeable paved surface and covered with plastic sheeting pending disposal. The area of excavation is depicted on Figure 3. Excavation was conducted by OSHA -certified personnel of Elite IV Contractors under the technical supervision of Ground Zero. Mr. Sam Savig of EHD observed the excavation and soil sampling. Soil samples were collected from the backhoe bucket and with a drive sampling device at the limits of the excavation including four sidewall samples at the floor of the excavation and one sample from the center floor of the excavation. Soil samples were field -screened for the presence of VOCs using a flame -ionization detector (FID). One four -point composite sample was collected from the stockpiled soil. The samples were submitted under chain of custody protocol to state -certified Argon Laboratories (FLAP No. 2359) for analysis of TPHg by EPA Method 8015K BTEX by EPA Method 8020A and oxygenates by EPA Method 8260B. In addition, the soil pile composite sample was analyzed for total lead by EPA Method 7420. All work was conducted in accordance with Ground Zero's Quality Assurance/Quality Control Plan and the Site Specific Health and Safety Plan on file with EHD. Field notes are included in Attachment A. Results Other than a slight hydrocarbon odor noticed at shallow depth, no field evidence of contamination (FID readings, odors, soil discoloration) was apparent in soil exposed in the excavation. Analytical results of excavation soil samples were non -detect for all compounds except for 0.009 parts per million (ppm) MTBE in sample WLM-C-9'. The soil pile composite sample contained 0.008 ppm MTBE and 5.7 ppm total lead. Analytical results are summarized in Table 2. Laboratory reports and chain of custody documentation are included in Attachment B. Conclusions and Recommendations The trace of MTBE detected in sample WLM-C-9' is not believed to indicate a significant level of contamination is present in soil. The four samples collected from the sidewall corners at the floor of the excavation were all non -detect, defining an extremely limited lateral extent of contamination (radius less than 3 feet). The vertical extent of contamination is in all likelihood not much greater than the base of the excavation. Between the depths of 4 and 9 feet, the concentration of MTBE diminished from elite\wlm\excret. doc