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rThe well water analytical chemistry resultsrobt ' ed from the on-site domestic well indicate that the nitrate impact to the underlying aquifers rs high. his impact is probably due to the large agricultural roductieand area directly upgradient o the oject site. SSS§ 6.8. /the Average Daily Flow is calculated t 'be gals/day om the Men's and Women's Restrow2 based on the S.J.C. Sewage Standards. ITh, e Apph a on Rate at the native soil-effluent interface is 1.2 gals/ft2/day from the obtained perc rate o 3.2 min/in at the 40 inch perc test depth. However, the imported clay loam material should possess a perc rate of approximately 25 min/in, which should translate to Application Rate of approximately 0.593 gals/ft2/day. Therefor -r is 2 ft width x 300 LFLL=600 square feet of infiltrative floor surface, this area should acclTt 356 gallons per day(600 ft2 x 0.593 gals/ft2/day= 356 gal/day). NLS§4.1 The nitrate loading potential cat ed on Page 11 indicates the percolating effluent may have a resultant nitrate concentration of 16 ppm nitrate, which is below the drinking water Maximum Contaminant Level (MCL)o The underlying groundwater aquifers contain a nitrate concentration of approximately 41 ppm nitrate. Consequently, the recharge effluent water should theoretically add a dilution effect to the aquifers that were tested. This is theoretical and based on the assumption that water table receiving waters eventually percolate into the lower aquifers. RECOMMENDATIONS AND MAINTENANCE A maintenance program should be established for the wastewater disposal system. Predicting septic tank pump-out intervals is impossible due to the number of unknowns. These unknowns lead to changes in the quantity, quality and operational parameters of the proposed septic system. The Restrooms should be checked a number of times a day to guard against vandalism, such as forcing the faucets to run continuously. It is anticipated to have the tank pumped every three years, or pump-out based upon analyzing the scum and sludge thicknesses after a year of operation. The second maintenance issue will be the washing off of the septic tank filter periodically,preferably at tank pump-out. A water line with a hose bibb is adjacent to the septic tank location for filter maintenance. A clean-out must be installed on the ABS influent tightline from the Restrooms to the septic tank. As depicted on the Parcel Viewer aerial photograph, a fresh water pipe connects the well to the pressure tank,in a direct line. This water pipe is buried six feet deep. The east leachlines will traverse over this water line. EHD will specify the leachline pipe details as the pipes' cross above the water line, but typically blank(non-perforated) pipe, or encased pipe must extend five feet on either side of the fresh water line. The building designer/engineer/architect, the plumber,the landscaper, and the wastewater disposal system installer must all coordinate so that proper grades are established and maintained. 14 Chesney Consulting