Laserfiche WebLink
November 19, 2004 <br /> NOA Project Number: E040107A <br /> ground water flow from up-gradient areas. These processes would generally contribute to additional <br /> reduction of nitrate-nitrogen concentrations in ground water to the extent that the nitrate-nitrogen <br /> concentration of ground=water flow from up-gradient areas is lower." <br /> The Hantzsche and Fennemore approach is "...a conservative (worst case) first approximation of <br /> ground-water nitrate-nitrogen concentration resulting from the combined effect of on-site sewage <br /> disposal systems and precipitation. This (the equation and approach) is for estimation of long-term <br /> effect (i.e., over years) on ground-water quality, and is not intended for prediction of seasonal <br /> changes" (Hantzsche and Finnemore, 1992). <br /> The method takes into account the development area, soil denitrification-factor, rainfall volume, <br /> rainfall nitrate concentration,waste effluent quantity, and waste effluent nitrate concentration. The <br /> formula, assumptions and calculations used for the analysis are shown on Plates 4 and 5. The units <br /> of nitrate used in the mass balance equation are nitrate-N,whose maximum drinking water <br /> contaminant level is 10 mg/L. <br /> F! <br /> 1.0 CHEMICAL AND PHYSICAL PROPERTIES OF SOIL <br /> F11.1 Chemical and Physical Soil Properties <br /> F1For a discussion of on-site soil properties, refer to Section 5 of the SSS. <br /> 1.2 Mass Transport Soil Properties <br /> The soil profile examined on the Site contained sandy clay, after the surface soils, and the silty sand <br /> ! to a depth of 10 feet. The soil at a depth fo.1.5 feet had a permeability of 25 minutes per inch in a <br /> percolation test. This rate is considered moderate. <br /> F1 <br /> 2.0 GROUNDWATER ANALYSIS - <br /> 2.1 Regional Ground Water <br /> A discussion of regional ground water, including depth to ground water,is included in Section 4.1 of <br /> F1the SSS. The ground water depth below the site was found to be 8.5 feet on October 28, 2004, <br /> 2.2 Potential Ground Water Contamination Issues <br /> A discussion of issues related to potential ground water contamination is included in Section 4.3 of <br /> the SSS. <br /> # 1 <br /> P! <br /> 2 <br /> kl <br /> lJ r <br />