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