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remediation at the Chevron site, groundwater can return to its normal eastward flow direction and hydrocarbons can resume their migration from the Chevron site to the Kwikee site_ We see no contradiction in this assertion; as explained in sections 4.8 and 4.10, TPH-g concentrations were declining at a rate of 30-40% each quarter prior to shutdown of the DPE unit in early 2002 and have declined at the same rate since the unit was reactivated in mid-2002, and it was only during the period during which the unit was shut down that concentrations at both sites reversed this decline. EHD also noted that a hole was observed in the underground storage tank when it was removed, and asserted that the Kwikee site has not been well assessed. We fail to see the basis for this assertion, unless EHD believes that further drilling will discover soil contamination that has not been found during past drilling activities. Twelve borings have been drilled on this relatively small site, including one that was drilled directly through the UST pit and was cored almost continuously to a depth of 35 feet and three others that were located within 15 feet of the UST pit. A state-certified laboratory analyzed 26 soil samples from these borings, and detected no Total Petroleum Hydrocarbons beneath the UST pit. Only one of the 26 samples contained TPH-g above this limit, at the extremely minor concentration of 298 mg/kg. We therefore insist that the site has been sufficiently assessed to determine that the soil is not contaminated. Further, no additional groundwater assessment is necessary, because the contaminant Iimit has been delineated on three sides by data from five wells, three of which are screened above the present piezometric surface. Additionally, wells are in place and data are already available on the fourth side and are being monitored by Chevron. Hence, further investigation in that direction is also unnecessary. o EHD also disagreed with Upgradient Environmental's assertion that language in State and Local Oversight Program contracts regarding the 30-day comment period for regulatory response to work plans can also be applied to Closure Requests and monitoring reports. Upgradient Environmental spoke with Mr. Kevin Graves, head of the Petitions Unit at the State Water Resources Control Board, Mr. Rick Rempel, formerly with the State Board, and Mr. George Dunfield, formerly with the petitions unit at the State Underground Tank Cleanup Fund Program concerning this issue. According to these individuals, personnel at the State Board do not necessarily share EHD's view on this issue, and in some cases this 30-day comment period may apply to such reports. All three gentlemen were familiar with one particular case in which the regulatory agency did not respond to a Closure Request within 30 days, and the State Board closed the case on the 3 s`day without further review. 24