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erratic, patchy effluent distribution patterns in response to the normal "trickle" flow of effluent through septic systems. Since this can be overcome with the use of pressure distribution methods (i.e., pumped effluent dispersal), I recommend the designer either: (a) modify the design to incorporate pressure distribution in place of gravity piping; or (b) provide analysis of how patchy, gravity effluent distribution could adversely affect vegetation management and nitrogen removal rates. Unreasonable Homeowner Responsibilities. The proposed system places significant responsibilities on the homeowner to manage and monitor an intensive grass growing, mowing and disposal operation for the life of the system in order to maintain a compliant onsite wastewater disposal system; this is an unreasonable expectation. Additionally, with no supporting performance history or operating data for the proposed design, the homeowner will have the added responsibility to document and prove the viability of the novel experimental design concept. This is an unreasonable burden to place on the homeowner, which is one of the primary factors behind the State OWTS Policy requirement for NSF certification or other third -parry testing of supplemental /alternative treatment processes — before being approved for use. For full disclosure to the system owner and the County, I recommend that the designer provide estimates of expected labor, material and testing costs for the proposed system, covering the start-up testing years and beyond. Alternative Mitigation Approach In addition to reviewing the nitrogen mitigation design by Chesney, I reviewed the project site and immediate vicinity and believe there are significant land use and hydrologic factors that could allow for the consideration of an alternate nitrate mitigation approach at this site. Specifically, the proposed project site is bordered on the northeast by the railroad easement and beyond that French Camp Road right of way. These bordering public/utility lands contribute additional rainfall -recharge to the groundwater system adjacent to the project site with no additional nitrogen loading; this will effectively dilute the nitrate concentration effects of the proposed 4 -bedroom OWTS. From my preliminary assessment, I estimate the additional adjacent land area more than doubles the amount of rainfall -recharge value that can be included in the nitrate loading calculations for the project. This would have the effect of reducing the projected nitrate loading calculations below the 10 mg-N/L criterion, which could then allow the proposed residence to utilize a standard septic system. Since the adjacent railroad and public road have no likelihood of changing in the foreseeable future, I believe this is a reasonable alternative nitrate mitigation strategy the County could consider for this unique situation. 3