Date implemented:
October 10, 1997

Final remediation design:
System operation was checked weekly during the first three weeks of operation and monthly thereafter. During each site visit, the vacuum of each soil venting well was measured at the manifold and at the wellhead; the vacuum of the three monitoring points, nearly monitoring wells, and the blower intake were measured. Also, the flow rates of the soil venting wells and discharge were measured; and the total organic vapor (TOV) concentration of each soil venting well and the discharge was measured. The system was designed so that individual soil venting wells could be isolated from the system to alleviate potential stagnation zones. It was noted that the TOV concentration increased to over 100 ppm in SVE lines that were closed off and there was no flow. The TOV concentration at the well head was indicative of concentrations observed when the lines had airflow. This indicates that maybe the PVC or glue was responsible for the elevated TOV concentrations in stagnant lines. Therefore the concentrations detected in the stagnant lines are considered anomalous.

Results to date:
Soil: The result show that the PCE concentration of the discharge decreased from 160mg/m3 on October 20, 1997 to 2.3mg/m3 on May 8, 1998. Cis-1,2dichloroethene (DCE) was detected at a concentration of 7.2mg/m3 in the October 20, 1998 sample, but was not detected in the remaining samples. The PCE air emissions decreased from 17,532