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saturated zone soils of MW-08 will come into contact with the enzymatic complex/bacteria water mixture, and biodegrade Initial conversations with Wayne Pearson of the Regional Water Quality Control Board (RWQCB), Central Valley Region, indicated that a general permit would be ' required for the re-injection portion of the remediation AReport of Waste Discharge that includes the required permit form and supplemental data is provided in Appendix D Under the General Permit, the acceptable levels of TPH-g/BTEX in the re-entering stream are non-detect To ensure that non-detect levels are attained for TPH-g/BTEX by the remediation system, samples from the sampling port in the exit line of the mixing tank will be collected and analyzed for TPH-g/BTEX (EPA Modified 8015 and EPA Method 8020) If TPH-g/BTEX levels are detected, the ' holding time of the stream will be increased (injection rate decreased), until non- detect levels are achieved To ensure that nitrogen levels are not increased by the ' bioremediation process, samples collected from the sampling port in the exit line of the mixing tank will also be analyzed for TKN, ammonia, nitrate, and nitrite (EPA Methods 3514, 350 3, 353 2, and 353 2) If nitrogen is detected in excess of background levels, a nitrogen removal system will be installed During the first two days of start-up, one sample from the exit line will be collected every six hours These initial samples will be used to adjust the extraction rate, modify the enzyme feed rate, and determine the appropriate stream retention time. After the first two ' days of start-up, the sampling frequency will be reduced to once every 12 hours During "long term" operational mode, samples will be collected once a day to ensure ' compliance with the re-injection permit requirements The remediation will be considered complete when groundwater samples from MW-01, MW-08, and MW-09 indicate non-detectable levels of TPH-g and BTEX Samples from these three wells will be collected weekly Final cleanup levels for the Stockton site will be determined by the SJCPHS and the RWQCB, in conjunction ' with the District, as part of the RAP concurrence and permit application process 2.5 Monitoring To verify that the groundwater and saturated soils at the site have been remediated, quarterly monitoring of wells MW-01, MW-08, and MW-09 will continue ' for one year after completion of remedial activities If no levels of TPH-g and BTEX are detected after this verification period, a request for site closure will be ' made to the SJCPHS If TPH-g or BTEX constituents are detected in the 94RS Fast Bay Municipal Utility District 40429601 rap 13 Remedial Action Plan