SITE INFORMATION AND CORRESPONDENCE

Home Browse Search

to have occurred when the design set points for the sparge pressures at the AS wells and the vacuums at the SVE wells have been reached and maintained for more than three consecutive days. For the AS system, water levels and dissolved oxygen concentrations in the monitoring wells within the treatment zone and the system operation data (e.g., injection airflow, pressure, and temperature at the compressor outlet and the individual AS wells) will be measured at least once daily during normal work hours. After completion of the startup, monitoring will be conducted weekly in the first three months of startup. Thereafter, well and system monitoring will be conducted monthly in the first year of startup or on an as-needed basis to aid in optimizing system operations. System monitoring will generally be conducted quarterly for the remainder of the treatment period but may be subjected to changes. For instance, after the first year of operation, system adjustment may be made if appropriate to enhance its treatment performance. Adjustment may include operating the AS wells in cycles, as in pulsed mode, to facilitate further hydrocarbon removal from the subsurface. Routine SVE operations include, in addition to vacuum and flow measurements at the SVE wells and the oxidizer, monitoring of wellhead vapor concentrations by PID/flame ionization detector (FID) measurements and system vapor influent sampling. Vapor samples will be collected using a SUMMA® canister and submitted to the off-site laboratory for analysis of TVPH and VOCs. Vacuum and PID/FID data will be taken likewise at the VM wells. SVE system monitoring will be conducted along with the AS system, at the same time and same frequencies. Weekly visual inspections will be conducted on critical plant and well field components. Safety shutdown interlocks, including the liquid-vapor separator high-level shutdown, the oxidizer shutdown, and the cascade blower-compressor shutdown, will be tested quarterly but the test frequency may be adjusted as necessary. Any components found to be defective will immediately be taken out of service and repaired or replaced. Unscheduled interruptions to routine operations of the AS/SVE system will be reported to CVRWQCB within 24 hours of discovery. A schedule for system restart will also be provided following assessment of the cause for the shutdown. RA Work Plan Oc109 Revl.doc 6-2 Shaw Environmental,Inc.