WORK PLANS FILE 1 - Laserfiche WebLink

Home Browse Search

i Work Plan for Additional Assessment ARCO PacilityNo.2186 Stockton,Califomia Page 7 i Influent and effluent soil vapor samples will be collected after a steady flow and vacuum have been established. The air sample will be forwarded to a State Certified laboratory to be analyzed for TPHG by EPA method 8015, and BTEX and .MTBE by EPA method 8020. Field observations such as flow rate, applied vacuum at the wellhead, induced vacuum in the observation wells and distance to the observation wells will be recorded. This data will be used to calculate a radius of influence for the vapor extraction well. This test will be repeated on wells VW- 2 and VW-3. The total duration of all tests is anticipated to be 1.5 days. REPORT PREPARATION After completing the installation of the monitoring wells, completing the vapor extraction test, sampling the wells (including the vapor extraction wells), and receipt of the laboratory results, Delta will prepare a report of findings. The report will summarize previous work conducted and present the findings of the additional assessment and feasibility study. The report will include but not be limited to groundwater flow and gradient maps (including data from the vapor extraction wells) analytical tables, a scaled site plan, geologic cross sections, certified analytical reports, boring logs, and feasibility testing data. The results of the vapor extraction test will be used to conduct a feasibility evaluation of remedial alternatives. This portion of the report will include the following, * Summary of analytical results of soil vapor samples, • Tabulation of field observations, • Radius of influence and mass extraction rate calculations for each vapor extraction well, and • Evaluation of remedial alternatives. SCHEDULE A well permit application, City encroachment permit application, City revocable permit request, and a Parks and Recreation access agreement were submitted the date of this report. PHS/EHS assistance I in obtaining the required permits and access from the City may be necessary; in order for Delta to meet the required due date for completing the field work by August 18, 2000, as stated'in PHS/EHS letter dated June 30, 2000. Upon receiving approval on the above-mentioned items and approval from PHS/EHS, the proposed work will be scheduled. It will likely require approximately two weeks for a drilling rig to become available and drilling activities will take approximately five days. Well development, sampling and casing elevation surveying will require an additional five days. Laboratory results will be received two weeks following groundwater sampling. The report of findings will be submitted'to PHS/EHD within three weeks of receipt of all analytical reports. I I