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PILOT TEST RESULTS Vacuum readings derived from the extraction wells (EX, P1 and P3) show a tight formation (high vacuum) . Also vacuum readings obtained from the ground water monitor wells (used as vacuum ? influence observation wells) show vacuum influence covering most of the site with the exception of MW-6, see Figure 6A. The bag samples obtained from the exhaust of the blower indicate that 59.2 pounds per day of total fuel hydrocarbons can be produced from the three extraction wells with an average flow rate of 30 cubic feet per minute from the formation. This vapor stream contains 0.92 pounds per day of Benzene, 2.04 pounds per day of Toluene, 0.74 pounds per day of Ethyl Benzene and 11.3 pounds per day of Xylenes, indicating an aged petroleum product contamination problem. A total of 1160 pounds of gasoline range hydrocarbons were removed during the pilot test. INTERIM VAPOR EXTRACTION VAPOR EXTRACTION SYSTEM DESIGN Wells P1, P3, EX, MW1 and MW5 have been manifolded to a vapor k extraction system with individuated valved orifices for flow control and measurement from the individual wells, see Figure 7 and Appendix A-Figures 5B1 (3/22/91) , 5B2 (3/22/91) and 5B1 (4/10/91.) . The individual wells were fitted with a PVC "T" heads (4" reducing to 211) with a locking air tight cap, for well access. The T lateral (211) was fitted with a 1/4" pipe to tubing fitting for obtaining vacuum/pressure and temperature readings. A pipe to hose 2" union was _nen placed between the "T" and the 2" PVC flex hose that goes from the well to the extraction manifold. At the manifold the individual wells are connected to their own: 21' PVC riser (3611 in heigth) with an orifice plate and a gate valve at the top of the riser. Vacuum/pressure ports are located on- either side of the orifice plate. Each orifice (well) has its " own, monometer (calibrated in millimeters (mm) Water) which are' hooked to the ports for oontinuous-<ida of flow from a particular well. All the extraction 'wells are manifolded together above the gate valve to a set of two orifice risers that are in parallel prior to the vacuum pumps, see Figure 3D. After the vapor stream leaves the manifold, to. flows througha moisture drop out drum (55 gallon 17E) and then is pulled into the pumps (two RotronDR606 placed in series) prior to entering a second moisture dro t drum and than onto activated charcoal vapor scrubs p out, At- the -initial-start--u �r j, -- - - - -- - - - — -- _-- p--of-the system a.Cyclo-Purge unit was used for mositure dropout (4/26/9.1-5/23/91) . It was later decided to utilize two 55 gallon 17E drums with galvanized Piping as page 7