ARCHIVED REPORTS XR0006543 - Laserfiche WebLink

Home Browse Search

R603 UPDATE-12 12/22/92 40 Then the syringe is filled, the sample valve closed, and forceps are clamp onto the soft polytubing to create an air tight seal before removing the syringe from the sample port Once the 60 cc syringe is removed with the clamped polytubing attached, the plunger is pushed into the syringe to create pressure within the syringe and released to allow the collected vapors to reach equilibrium A small dedicated needle attached to a dedicated 1 cc syringe is then inserted into the 60 cc syringe via the soft tubing for obtaining the sample to be injected into the PID-GC Again the 1cc syringe is purged numerous times before filling it with the sample All but 0 5 cc of the sample is ejected into the air before infecting the remaining 0 5 cc syringe sample into the GC-PID (the calibrant injection is 0 5 cc) Once the chromatogram is recorded an instrument blank is run prior to the next sample . The instrument blank indicates if residual peaks are being carried onto the next analysis While the GC-PID analysis is running for a particular sample (15 minutes per sample run) , vacuum influent readings are obtained from the wells by attaching a manometer calibrated in mm water to sample ports at the well heads These readings show the mm water pressure or vacuum that is being created at each well Occasionally the 10550 PID-GC is not available for field determination of the influent and effluent streams . Tedlar bag samples are then obtained and brought back to the WEGE portable laboratory for analysis using an FID-GC, see Appendix C - Field Notes . VAPOR RECOVERY OPERATIONS AND RESULTS As stated in earlier reports, soil contamination exists from beneath the tank excavation to the top of the ground water, see Fence Diagram Figure 6 Overexcavation during the initial tank removal, removed contaminated soil to the 25 foot depth. Before replacing the new double contained fiberglass tanks and dispensing system, 4 inch and 6 inch SCH 40 PVC 0 . 02 inch slotted pipes were placed vertically at the north corner and west corner of the excavation respectively and manifolded via underground to the treatment compound with SCH 40 2 inch and 4 inch PVC pipe. These pipes along with monitor wells MW1, MW2 , MW3 and MW10 are used for vapor extraction for soil and ground water remediation On October 10, 1991 the vapor extraction system operated six L L 1_ s..L i-.-, l.. �.�.. r7 —rr.-+o r�� A f-iii r+t i ^" r-%f t}1P 11UL1J' s, l o clie ck 1.h.e aLLL.V .rye 111A 1..Cd0 W l i s aiiu tdci� —. —ti.4 a44—Al REMOX unit, using monitor wells MW1, MW10, and the excavation wells . The system was restarted on October 17, 1991 and initial inspection and operation of the system occurred The unit operated until November 5, 1991, when it was shut down to replace a worn bear a ag . The system was rest-ar ted on November 20, 1991 and operated until December 24, 1991 . On this date someone turned off the main breaker that services the treatment compound This breaker box has since been locked. The unit was restarted on January 3 , 1992 and operated until July 20, 1992, with PAGE 7