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ran for a total of approximately 97 hours during the test. Groundwater and soil vapor were
<br />removed simultaneously from the test wells by applying a high vacuum to a drop tube that was
<br />lowered below the water table within each test well. Results of DPE feasibility testing indicated
<br />the following: (1) an effective radius of influence of at least 36 ft to the west of 2AMW-14; and
<br />(2) the removal of an estimated 212.3 lbs. (34.2 gallons) of TPHg from soil vapor, and
<br />approximately 0.29 lbs. (0.05 gallons) of TPHg, 17.56 lbs. (2.46 gallons) of TPHd, and 8.29 lbs.
<br />(1.13 gallons) of TPHo from groundwater. Results are summarized in SECOR’s report entitled
<br />Results of Additional DPE Feasibility Testing, dated May 23, 2003.
<br />From March 10 through April 9, 2003, 12 shallow zone groundwater monitoring wells (MW-18
<br />through MW-23, MW-25, MW-28, MW-30, MW-31, MW-33, and MW-34), eight deep zone
<br />groundwater monitoring wells (MW-16, MW-17, MW-24, MW-26, MW-27, MW-29, MW-32, and
<br />MW-35) were installed, and seven soil borings (SB-1 through SB-6 and MW-16A) were
<br />advanced at the Site. Results are summarized in SECOR’s report entitled Additional
<br />Assessment Report, dated May 30, 2003.
<br />From October through December 2003, five additional DPE wells (DPE-8 through DPE-12) were
<br />installed and a DPE remediation system was installed at the Site. The DPE system is
<br />connected to wells DPE-1 through DPE-12. Additionally, a Non-aqueous Extraction Technique
<br />(NETTM) SPH removal system was installed at well 2AMW-14. System installation activities are
<br />summarized in SECOR’s report entitled DPE Well and System Installation Report, dated
<br />December 5, 2003.
<br />On December 17, 18, and 22, 2003, exploratory excavations were conducted at the Site to
<br />locate underground utilities including former product pipelines. Steel pipelines were discovered
<br />at the Site at 14 locations. Results are summarized in SECOR’s report entitled Revised
<br />Underground Utility Search Report, dated March 5, 2004.
<br />In January 2004, SECOR completed construction of the DPE system. Electrical power and
<br />natural gas service were established by Pacific Gas and Electric (PG&E) on March 4, 2004.
<br />Under the conditions of the initial air permit for the DPE system issued by the San Joaquin
<br />Valley Air Pollution Control District (SJVAPCD) in April 2003, which covered the first six months
<br />of system operation utilizing propane as a fuel source, startup of the DPE system was
<br />performed and initial groundwater and air influent and effluent samples were collected on March
<br />18, 2004. SECOR submitted a request to the SJVAPCD for modifying the existing air permit,
<br />which included the operation of the DPE system using natural gas rather than propane, and
<br />extension of the life of the permit. SJVAPCD required that the revised permit be resubmitted for
<br />public review over a 30-day period, which ended on July 15, 2004. Throughout the duration of
<br />the review period, the SJVAPCD did not authorize the operation of the DPE system under the
<br />existing permit due to minor detections of polyaromatic hydrocarbons (PAHs) in the effluent
<br />sample collected on March 22, 2004. Since no public comments were received by July 15,
<br />2004, the SJVAPCD issued the revised air permit on July 20, 2004. Initial start-up and
<br />shake-down of the DPE system was performed on August 2 and 3, 2004.
<br />Concurrently during the installation of the DPE system, SECOR submitted the report entitled
<br />Work Plan For Pipeline Abandonment, Removal, and Soil Vapor Extraction Well Installation,
<br />dated April 15, 2004. This report outlined a plan for abandoning or removing the steel pipelines
<br />that were discovered during the December 2003 underground utility search on the Parcel 2A
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