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'� vrxp+fi�,3�1�'tn�� . a�, ,Z" ,�< �. L' ..r..1a h.. '� -.xf 5- l AN"'� }w ,�:i t. ,✓.;.rL(5!C- r ]sfkr{ r ds Jai" '� ,;� 'f` .Y!• ;.4i' r 7�?u.Ii r r � .7,5 K +ie w1" ':.5 4? �J"'a 4'"'�-�2?""'� .; +•, - r N ;. +: 0"N" .°� r` c! .,'rid-V. r 'F. �' J.r -S -v 4��,,:� �"_ �'.Y;w.'S`�'.� ";��' �i..�y�.;• eu." f _ M F J . Sr^rl fkas`_on_R_y 1425-% - and Instrument Diagram(P&WD)for the Vapor Extraction System and illustrates the configuration of the carbon beds. The blower and carbon beds would be located inside the dock area as shown on Figure 3. The carbon beds are rated at approximately 60 CFM_ and each contains approximately 180 pounds of activated ,carbon. The configuration that is sbown in Drawing M-1 would allrw unrestricted discharge of the blower and a lead-polish arrangement to prevent air pollution when the lead units are exhausted. These units can be regenerated and recycled for future use. 4.4 Toro-inch diameter PVC piping would be used as vapor conduit between the well and the biow(,r, between the blower and the carbon beds, and between the lead and polishing carbon beds. Piping runs would be minimized by locating the blower and carbon units as close as possible to the extraction well. 4.5 Air velocity between the header pipe and the blower would be used to estimate air-extractior rates during the Pilot Test. Air velocity would be measurers by correlation of a vacuum gauge, localed in the blower suction piping,with blower performance curves. 4.6 Sample taps for the collection of vapor samples would be located at the inlet to the first stage carbon units and at the outlet of the first and second stage units. Samples would be collected and analyzed as described below in the sampling plan. An additional sampling Up would be located at the inlet and the outlet of one of the first stage carbon beds. 4.7 Two surge tests would be performed,during which time the blower would be shut down. Two such tests are anticipated. The first test would allow the subsurface vapor to equilibrate for 24 hours before restarting the blower. V©C concentrations would be measured at the vapor inlet during blower restart. Inlet VOC concentration values would be used to evaluate the cost-effectiveness of a catalytic oxidizer vs. carbon and intermittent operation of the full scale system. Savings on power cost and carbon consumption may be realized by intermittent operation. The second test would be done with a longer or sborter equilibration time as established empirically from the resulds of the first test. Additional surge tests would he conducted if needed to optimize the most economical operational interval. 4.8 Vadose-zone permeability would be estimated by using techniques that are analogous to aquifer testing in a confined aquifer system. Pressure drawdowns would be obtained from water levels in manometer tubes that are located at radial distances from the extraction well of approximately 15,30 and 50 feet. The manometer tubes would be installed by drilling an 8"borehole and installing 1/2" PVC pipe (for the 30' dep(h) and 3/4" PVC pipe (for the 63' d--pth). The top end will be open to the atmosphere, allowing measurement of the vacuum v pressure from the subsurface interval at its radial distance from the extraction well. Volume rates of air extraction will be determined from the blower curve. A plot of pressure drawdown versus time will be Used to estimate "gas .� B-3 REMEDIATION SERVICES, INC.