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during these tests Clearwater reported that induced vacuums were measurable at monitoring points up to 40 feet from the SVE wells and induced pressures could be measured up to 55 feet away from sparge wells Hydrocarbon vapors were obtained from both SVE wells, and concentrations increased by at least 100%during the spargmg test 2.3 Site Remediation In 1996, after the feasibility testing was completed, Clearwater submitted a Corrective Action Plan to use soil vapor extraction and air sparging to remediate the site The plan was approved by EHD, and Clearwater prepared a cost proposal for tlus method The proposal was rejected by the State UST Cleanup Fund as being too expensive, and this plan was abandoned In subsequent correspondence to Mrs Conrady, PHS/EHD suggested the downhole application of Oxygen Release Compound (ORC) as a less-expensive alternative method of site remediation Regenests, Inc , the manufacturer of ORC, used the laboratory data supplied by Clearwater and calculated that 1,000 pounds of ORC powder would be required to successfully remediate the groundwater contamination Clearwater then submitted a second Corrective Action Plan in August 1997, proposing mjection of the ORC slurry into ten Geoprobe bonngs A cost estimate for this method was also rejected by the UST Cleanup Fund as being too expensive, and Mrs Conrady was instructed to seek competitive bids for the work Then, in written correspondence in January 1998, David Deaner of the UST Fund further instructed Mrs Conrady to reduce the number of borings by half, necessitating a concomitant reduction in the amount of ORC powder 2.3.1 ORC Infection and Monitoring Upgradient Environmental Consultants responded to a solicitation for bids in January 1998 The solicitation requested estimates to inject 500 pounds of ORC into five borings Upgradient's estimate was approved by the UST Fund in February 1998 After reviewing the previous work by GeoAudit and Clearwater, Upgradient prepared a revised CAP proposing injection into 7 Geoprobes (Figure 7) Tlus plan was approved by PHS/EHD in March 1998 The injection borings were drilled in April 1998 The borings ranged in depth from 20 to 35 feet, and injection occurred within a 10-foot interval in each boring (Figure 8) Injection volumes ranged from 11 to 55 gallons of slurry, for a total of 271 gallons Dissolved oxygen concentrations were measured in all of the existing wells and groundwater samples were collected from each well to establish a baseline for future monitoring of these parameters Dissolved oxygen concentrations were monitored in two 3-month periods m 1998, and groundwater samples were collected quarterly in accordance with the CAP Upon completion of the approved scope of work, PHS/EHD requested Upgradient to prepare a Closure Report summarizing the investigation and remediation of the site 3