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e � FFbelow OUNDWATER TEST RESULTS nes of Equal Depth Map illustrate the groundwater depth to be approximate7aquln d surface. The 1999 Lines ofEqual Elevation Map published by the San Jod Control illustrates the groundwater elevation and the directional flow. It the groundwater is very flat,but flowing in an east-northeast direction toward a zone of recharge. A. Domestic Well Water Test Results A well water sample was obtained for analysis from a hose bibb next to Mr. Lawley's pump house. The well pump was allowed to run for ten minutes before the sample was taken to ensure the sampling of aquifer formation water. A plastic bottle was used for the nitrate sample. Two glass VOC bottles, with preservative,were used for the DBCP/EDB sample. All three sample bottles were placed in a cooled ice chest and transported to A&L Labs in Modesto under the attached Chain of Custody. The groundwater sample reveals a nitrate concentration of 34 mg/L(ppm). The Maximum Contaminant Level(MCL) for nitrate is 45 ppm(as nitrate). Dibromochloropropane and Ethylene Dibromide(DBCP and EDB)was not tested per Mike Huggins of EHD since these materials were never used in the surrounding areas. Unfortunately, no well log was available to inspect the underlying lithology for this well or any other domestic wells in the area. B. Alkalinity Requirements for Nitrification For nitrification to occur, alkalinity must be consumed. Nitrification consumes approximately 7.1 mg of alkalinity for every milligram of ammonia-nitrogen(NH4-N) oxidized. The nitrate-nitrogen loading calculations below are contingent upon the environmental factors required for nitrification to occur. Alkalinity in wastewater effluent plays a role in nitrification and is derived from the domestic water supply and the introduction of wastes to the wastewater. Water chemistry for domestic wells in this area range from 150 ppm to 250 ppm. Waste introduction into any proposed septic system may be of a lower strength than what may be found in a typical household and may be more acidic due to the introduction of coffee, which is acidic. Consequently, 4 nitrification may be inhibited due to insufficient alkalinity from this introduction of acidic wastewater. C. Mounding Analysis Because the groundwater is comparatively deep below any proposed location of a disposal area, Mounding Analysis is not required or necessary. If it is determined at some time in the future that mounding effects from an unknown restrictive soil strata are preventing proper effluent treatment and disposal, the 100%replacement area may have to be activated. This may occur before failure of the primary leachfield. Chesney Consulting