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property, and locating pipelines that were anticipated beneath West Weber Avenue and the Waterfront Towers parking lot and beneath former Edison Avenue near the eastern entrance to the Delta View Apartments. The work plan also proposed the installation of horizontal SVE wells to extract petroleum hydrocarbons from soil beneath five apartment buildings to the south, west and northwest of the DPE remedial well field, and connection of those wells to the DPE system. The RWQCB-CVR approved the April 15, 2004 work plan and the June 14, 2004 letter addressing RWQCB-CVR comments to the work plan (Response to RWQCB-CVR Letter Dated May 14, 2004) in electronic correspondence dated June 21, 2004. SECOR completed pipeline abandonment/removal activities during the fourth quarter 2004, and the installation and connection of horizontal SVE wells to the DPE system during the third quarter 2005. Pipelines discovered during the December 2003 investigation, as well as additional pipelines discovered during pipeline abandonment/removal activities, were removed from the undeveloped portion of the L&M OU, soil was excavated to approximately 10 ft bgs, a 500-gallon steel UST was removed, and old well was properly abandoned, and pipelines trending off the undeveloped portion of the L&M OU were rinsed and filled with cement. Approximately 300 gallons of product/water mixture were removed from three pipelines and approximately 350 gallons of product was pumped out of the UST. Horizontal SVE wells were installed beneath the bottom of the excavation and the bottom was lined with a high density polyethylene (HDPE) liner. Additionally, six horizontal SVE wells were installed beneath five apartment buildings in the Delta View Apartment complex. Final results and a work plan for additional pipeline removal in the Waterfront Towers parking lot are presented in SECOR’s Pipeline Removal, Abandonment, Soil Excavation, On-Site Horizontal SVE Well Installation, and Horizontal SVE Well Installation Beneath Delta View Apartments Report and Work Plan for Pipeline Removal, Abandonment, and Soil Excavation in Waterfront Towers Parking Lot dated February 10, 2005. Additional assessment activities were conducted at the Site in May 2004 to investigate the vertical extent of petroleum hydrocarbons in the vicinity of the Site. SECOR advanced one deep soil boring (SB-7) to a depth of approximately 140 ft bgs in the vicinity of well MW-17, installed shallow off-site well MW-45, and installed deep off-site wells MW-40 through MW-44 and MW-46. Three groundwater samples were collected at 117, 128, and 139 ft bgs using a HydropunchTM sampling device in soil boring SB-7. Results are summarized in SECOR’s report entitled Additional Assessment Report and Work Plan for Additional Deep Groundwater Zone Assessment dated July 29, 2004. From March 21 through April 10, 2005, additional assessment activities were conducted at the Site. Seven B-zone groundwater monitoring wells (MW-47 through MW-53), one groundwater monitoring well intended to be a C-zone well (MW-54), and one groundwater monitoring well intended to be a D-zone well (MW-55) were installed, and three Geoprobe soil borings (GP-1 through GP-3) were advanced. Results are summarized in SECOR’s report entitled Additional Deep Groundwater Zone Assessment Report, dated May 25, 2005. From July 13 through July 15, 2005, 16 soil vapor points were installed to monitor soil gas concentrations over time and determine radius of influence of the previously installed SVE system. On July 19 and 20, 2005 baseline soil vapor samples were collected from 12 of the 16 vapor points. The SVE system was initiated on August 18, 2005 for select wells. The complete scope of work and results of the soil vapor well installations, SVE start-up, and soil