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F1 November S, 2005 NOA Project Number: E05123B the facility falls under the Regional Board's Small Food Processing waver permit. Because of concern regarding nitrate leaching into ground water from septic systems, San Joaquin County EHD will require a nitrate loading analysis for the proposed development to estimate the potential concentration of percolating effluent from septic systems and rain fall over the long term. Where percolating effluent leaches into the ground,ground water quality may be impacted to some degree should the effluent reach ground water. The method utilized for the nitrate loading analysis is based on a simple mass balance formula, discussed in a published article by Hantzsche and Finnemore (1992),which provides a convenient F! and simplified method to estimate long-term ground-water nitrate impacts on an area-wide basis. Hantzsche and Finnemore found that over a long period of time,water quality in the upper Fisaturated ground-water zone closely approximates the quality of percolating recharge waters. They believe that their method is a good planning tool and provides useful information to planners and local officials but with some real limitations. In their article published in Ground Water, Hantzsche F1and Finnemore mention that "...the equation ignores dispersion, lateral flow, and mixing with ground water flow from up-gradient areas. These processes would generally contribute to additional reduction of nitrate-nitrogen concentrations in ground water to the extent that the nitrate-nitrogen Pconcentration of ground=water flow from up-gradient areas is lower." The Hantzsche and Feiinemore approach is "...a conservative (worst case) first approximation of Rground-water nitrate-nitrogen concentration resulting from the combined effect of on-site sewage disposal systems and precipitation. This (the equation and approach) is for estimation of long-term effect (i.e., over years) on ground-water quality, and is not intended for prediction of seasonal changes" (Hantzsche and Finnemore, 1992). The method takes into account the development area, soil denitrification factor,rainfall volume, rainfall nitrate concentration,waste effluent quantity, and waste effluent nitrate concentration. The formula, assumptions and calculations used for the analysis are shown on Plates 1 and 2. The units of nitrate used in the mass balance equation are nitrate-N,whose maximum drinking water contaminant level is 10 mg/L. 1.0 CHEMICAL AND PHYSICAL PROPERTIES OF SOIL 1.1 Chemical and Physical Soil Properties For a discussion of on-site soil properties,refer to Section S of the SSS. 1.2 Mass Transport Soil Properties Layered soils and sediments, such as the fine-grained soil layers found on the Site, typically provide a degree of protection between percolating effluent at the surface and shallow ground water aquifers. Soils of this type do not typically present a high risk of excessive mass transport of nitrate or other I 2