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7NLS§ SSS§ 6.7, SSS§ 5.4, 6.8. The soils directly underlying the proposed filter bed area meability that correlates with the texture analysis of the sandy loam/loamy sand receiving soils. However, shallow(-24")perc test results revealed apparent soil compaction, which may have been caused by farm machinery/implements. A backhoe test pit excavated adjacent to the existing vineyard east of the stormwater infiltration basin indicates probable denitrification evidence,with the nitrate-nitrogen concentrations decreasing from the 6 ft depth to the 9 ft depth by 31% (172 ppm to 118 ppm). This denitrification value of 31% was used in the nitrate loading calculations. New drinking water regulations focusing on supplying safe drinking water for all Central Valley residents while simultaneously protecting the economic viability of California agriculture, are prompting the introduction of several new programs to address regulations, one of which is the Nitrate Control Program (NCP). In addition,the California Sustainable Winegrowing Alliance (CSWA) advances the wine industry's commitment to environmental stewardship and social responsibility. The following lists the specific OWTS design parameters to mitigate nitrate impact, and promote environmental stewardship and sustainability: • The 4,000 gallon septic tank will retain particulate/organic matter received from existing septic tank carryover effluent that will be pumped to this tank. The large hydraulic residence time(HRT)this tank provides will reduce the organic nitrogen fractions through anaerobic digestion and removal of all nitrogen fractions by eventual tank pumping, thus ultimately reducing nitrate formation. • The Polylok PL-625 high flow effluent filter,rated for 8,000 gpd will trap particulate matter before effluent flows from the 4,000 gallon tank into the 1,500 gallon pump chamber tank. By trapping particulate matter, Biochemical Oxygen Demand(BOD) and Total Suspended Solids (TSS)can be reduced by 28%and 63%,respectively (Ref. 7,Pg. 183), thus creating a more favorable soil environment for effluent treatment. • The 1,500 gallon pump chamber tank has two compartments, with the first compartment adding additional HRT for trapping and digesting organic matter. • The two high head effluent pumps have built-in filter screens for additional particulate screening. • Effluent pumped to the filter bed will alternate between the two pumps and between the two zones of the filter bed. Equal distribution of effluent between the two filter bed zones will give each zone time to assimilate and treat the effluent within the soil environment by preventing saturated soil conditions to materialize. The pump cycles will operate"on-demand"and not"time-dose" since wastewater flows every 24 hours are anticipated to be relatively constant at least six months of the year; at pre-crush, crush and post-crush. Consideration may be given to time dosing the other six months of the year. Nothing is to be stored on, and no vehicles other than farm machinery/implements are to be driven i over the filter bed area. This farm equipment must be the lightest weight available,preferably with tractor treads to minimize psi pressure. Page -11- Chesney Consulting