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6.2 Description of the methods proposed to mitigate any known or future impact to soil and groundwater from nitrate and/or other constituents of concern, at and/or around the project site: The project, as described without any mitigation efforts, would not be feasible. However, the proprietary measure that will be installed, shall reduce the nitrate loading concentration to acceptable levels. The site is considering several alternatives, subject to cost, maintenance requirements and required area. All the measures being considered have to be EPA ETV approved and have approval of NSF/ANSI Standard 40 test protocol. At the moment, the primary option to treat the nitrate loading concentration would be a HDPE Tank Biofilter. The HDPE Tank Biofilter is ideal for increased nitrogen removal and are pre -assembled for faster and easier installation. The biofilter would not require an air compressor or complex moving parts. It is guaranteed to not require cleaning or replacing for 20 years. These tanks can be placed in series as required to reduce the nitrate loading concentrations below 10 mg/ L -N. The filter would require less maintenance and maintenance cost than an aerobic treatment unit, fixed film trickling filter, sequence batch reactor or a recirculating sand filter. Based on the studies performed by the EPA during a 13 month testing period, the Waterloo Biofilter reduced 59% percent of the total nitrogen with an average effluent of 14 mg/1 vs the 35 mg/1 of influent wastewater. Our site would only require the biofilter to reduce the nitrogen loading by 53%. If one biofilter tank were to result insufficient, another biofilter tank would be placed in series. Attached in the appendix shall be more information regarding this proprietary measure and the testing behind it. More information can be provided upon request. 7.0 CONCLUSION AND RECOMMENDATIONS SECTION The conclusions of this report are based on the information provided regarding the proposed development, the use of the subject property, and the site conditions as they existed at the time we excavated our test hole and performed the percolation test. It was assumed that the test hole and percolation test and the compiled data results are representative of the subsurface conditions in the general area. The site will comply with the San Joaquin County requirement by having a project site with less than 10.0 mg/L-N with the proprietary measure. The values used for calculations assume that the nitrate concentration of rainfall is 1 mg/L-N as previously noted (Hanztch/Finnermore). Also, the site contains denitrification processes and that based on uses the site effluent stream is 35 mg/L-N. Analyzing all the compiled data, the site is adequate for the proposed use. 7.1 APPENDIX Attachments are all included at the end of this report as part of the Appendix. ON