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R603 UPDATE-13 2/15/93 of the REMOX incinerator and analyzed in WEGE' s portable laboratory utilizing the Photovac 10s50 PID-GC and Shimadzu FID- GC. Just an influent sample was obtained on December 7, 1992 and influent from individual wells were obtained on December 9, 1992 . These samples were analyzed for TFH and BTEX along with screening for Tetrachloroethylene (PCE) , Trichloroethylene (TCE) and 1, 2 , -Dichloroethane (DCE) using a Shimadzu GC-FID chromatograph mounted permanently in WEGE' s portable laboratory. These compounds have the following retention times in the above chromatograph, DCE = 2 079 minutes, TCE = 3 023 minutes and PCE = 3 . 75 minutes Before sampling the wells or the system, a calibrant made from fresh gasoline is infected into the GC-PID and GC-FID The resulting chromatograms has numerous responses The microprocessor of the GC-PID and GC-FID computes the area per response in volt seconds and assigns a peak number and retention time . The sum of all the responses are then used to obtain a mg/L per volt second calibrant factor, which is used to calculate mg/L as gasoline vapor from each analysis produced. Pounds per day can be computed using these mg/L values produced from the analysis of the different vapor recovery wells, the influent to the oxidizer, the pressure differential created at the orifice to determine flow rates for each well , and the influent to the oxidizer. The pounds per day values for each well and the influent are averaged with the preceding site visit' s pound per day value. This figure is then multiplied by the number of hours the system operated between visits, to estimate the total pounds each well and the system has removed for that time period. This figure is added to the accumulated poundage of the previous visit to update the total pounds removed The effluent sample is computed in the same fashion, but also includes natural gas flow along with the influent orifice flow rate SAMPLING VAPOR STREAMS The vapor samples are obtained by attaching a dedicated air tight 60 cc syringe to a sample port on the vapor recovery manifold (on the well side of the orifice plate) with air tight fitted polytubing The sample port is opened and the syringe purged by pulling and pushing the syringe plunger several times . Filling and depleting the syringe of that particular well' s vapor stream 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 L t t-L. roat- nYGQ ail L71 thin IIP plunger l�S Yubileu inl..V 411c �"y'r ii�ge 'Co4v Ca..�-u.r�- 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 infection is 0 . 5 cc) . Once the chromatogram is recorded an instrument blank is run prior to the PAGE 6