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1 FINAL REMEDIATION PLAN 1399 East Yosemite Avenue Manteca California 3.1 Equipment ' Equipment used in the vapor extraction pilot test included an in-line particulate air filter, an air/water separator, a 10-horsepower regenerative blower (blower), a portable electric ' generator, pressure gages, airflow meters, temperature indicator, and a photoionization detector (PID) 3 2 Process The vapor extraction pilot test was completed by reducing the atmospheric pressure ' within the sod, using the vacuum side of the blower, to induce an airflow The exhaust air from the blower was vented to the atmosphere via a vertical 2-inch-diameter PVC exhaust stack with the discharge point approximately 15 feet above ground level The ' San Joaquin County Air Pollution Control District required no off-gas treatment for the pilot test ' 3 3 Procedure A portable blower assembly was transported to the site and situated adjacent to MW-1 B during the test The blower assembly was powered with a portable, 3-phase generator, and connected to MW-1 B via 2-inch PVC piping The blower exhaust was connected by a 2-inch PVC pipe to the exhaust stack Figure 7 is a schematic of a typical portable vapor extraction system Reducing the atmospheric pressure in the soil was achieved by the blower assembly ' creating a pressure drop in the sods around well MW-1 B This resulted in the development of a cone of pressure depression (CPD) The CPD develops radially outward from well MW-113 to the point where pressure in the subsurface equals ' atmospheric pressure The CPD causes an airflow toward well MW-1 B Air and gases collecting in the well casing flow through the blower assembly The exhaust from the blower assembly is directed through the exhaust stack ' 3.4 Test Situations and Results ' The pilot test was conducted in one 4-hour test session No fresh air was admitted artificially into the system The pressure drop was measured by connecting pressure ' gauges to outlying monitoring wells and noting the change in pressure The blower assembly was monitored for organic vapors by a PID at the intake to the assembly and on the exhaust stack The system airflows were monitored at the blower exhaust Measurements of air temperatures and pressures were collected at the intake to the blower assembly and at the blower exhaust Air samples were collected at the intake assembly and submitted to a state-certified laboratory for analysis by GC/FlD Method ' 5030 Air samples were collected at the end of the test Data from the pilot test is . summarized in Table 4 Results of analytical testing are included in Appendix B ' 90-098F RPT 5