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Treatability Study Report and Feasibility Evaluation for In Situ Petroleum Hydrocarbon Remediation Field Maintenance Shop #24, 8020 South Airport Way Stockton, California • Vacuum in well FMS-DPE2 (48.00 feet from FMS- DPE1) increased from 0.0 to 0.80 in. w.c. by the end of testing. • Vacuum in well FMS-MW1 (92.49 feet from FMS- DPE1) increased from 0.04 to 0.45 in. w.c. by the end of testing. • Vacuum in well FMS-MW2 (110.21 feet from FMS- DPE1) increased from 0.01 to 0.15 in. w.c. by the end of testing. • Vacuum in well FMS-MW4 (189.23 feet from FMS- DPE1) increased from +0.01 in. w.c. (pressure) to 0.065 in. w.c. (vacuum) by the end of testing. The induced vacuums listed above were used to determine the vapor extraction radius of influence using the "1 % method" described in Section 3.2.6. of this report. A summary of field data is provided in the HVDPE Test Summary Data sheets in Appendix F. 5.3.4. Radius of Influence for Vapor Extraction The vapor extraction ROI for HVDPE testing was determined based on applied and induced vacuums measured during testing at wells FMS-MW5 and FMS-DPE1 by applying the 1% method", as described in Section 3.2.6. of this report. At steady-state operating conditions of 204 in. w.c. applied vacuum and 40 scfm vapor extraction flow rate, the ROI of vapor extraction during HVDPE testing at FMS-MW5 was estimated at 7 feet, as shown in Graph 4. At steady- state operating conditions of 35 in. w.c. applied vacuum and 53 scfm vapor extraction flow rate, the ROI of vapor extraction during HVDPE testing at FMS-DPE1 was estimated at 100 feet, as shown in Graph 5. The discrepancy between ROI calculated for vapor extraction at FMS-MW5 and FMS-DPE1 is likely due to the differences in screened intervals between the two wells. Well FMS-DPE1 is screened from 20.1 to 60.1 feet bgs, intercepting the entire upper sand interval which was encountered between 21 and 28.5 feet bgs during well installation. At the location of FMS-MW5, the upper sand interval was found to extend from 20 to 25 feet bgs; however the top of the screen is set at 27.5 feet bgs, within the fine grained materials encountered below the upper sand interval. Therefore based on this evaluation of FMS-MW5, the HVDPE ROI is 100 feet (based on FMS-DPE1 results). The HVDPE ROI is illustrated in Figure 8. 5.3.5. Advective Airflow During the FMS-MW5 HVDPE test, advective airflow was measured in all the monitoring points where induced vacuum greater than or equal to 0.10 in. w.c. was observed. Measurements were taken under stable conditions near the middle of testing. The greatest recorded advective airflow was recorded in well FMS-DPE1, located 22.16 feet from FMS-MW5. At an extraction wellhead vacuum of 14 in. Hg and an induced vacuum of 1.35 in w.c., a 1 -liter Tedlar® bag attached to the wellhead of FMS-DPE1 deflated in 43 seconds (airflow of 1.4 liters per minute [L/min]). Well FMS-MW1 was the most distant well with a vacuum response over 0.10 in. w.c. At an applied vacuum of 14 in. Hg and an induced vacuum of 0.10 in. w.c., a 1 -liter Tedlar° bag attached to the FMS-MW1 wellhead deflated in 380 seconds (airflow of 0.16 L/min). Please see the Pilot Test Summary Data sheets in Appendix F for advective airflow measurements in seconds and in L/min in the observation wells. OTI E 32