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Test results indicate a comparatively high concentration of chloride at 249 ppm. Studies have found that septic systems contribute chloride to groundwater. Chloride travels as readily, if not more so, than nitrate in the vadose and phreatic (saturated) zones and can be the first indicator of septic contamination. The chloride concentrations in most groundwater formations averages 6 mg/I. The typical concentration of chlorides in untreated domestic wastewater is 50 mg/l, with the range being 30-100 mg/l. The nitrate concentration in the sampled well is above the median value of 22.5 ppm NO3, at 35 ppm nitrate. The Maximum Contaminant Level (MCL) for nitrate (NO3) in drinking water is 45 ppm. When interpreted together, the two test results for nitrate and chloride are a more positive indicator of septic influence than nitrate alone. The second water sample was retrieved from the aforementioned boring, off the groundwater table and is denoted as "TOP GW" on the report. As referenced, this top groundwater sample was analyzed to quantify impact from an existing leachfleld. The chloride (185 ppm), total dissolved solids (1596 ppm) and especially the nitrate concentrations (86 ppm) indicate impact from this leachfleld. E. SURFACE WATER INFORMATION The surface water retention pond for the existing and future development of the project is located at the north-center of the project. There should be no impact to impoundment water from any of the on-site leachfields. The pond is downgradient from the majority of the project and the addition of runoff water percolating into the top aquifer mixing layer may create a dilution effect. III. NITRATE LOADING STUDY RESULTS A. WASTEWATER FLOW PROJECTIONS AND CHARACTERISTICS To adequately determine nitrate-nitrogen loading from the project, wastewater flows must be determined as accurately as possible. Loading projections are based on the maximum or total number of employees and customers who may potentially use the toilet/sink, etc. on a daily basis. This incorporates an acceptable safety factor. Information for wastewater flow volumes was supplied by Mr. Pete Navarra and are found in the Appendix. It is assumed there will be no cooking within kitchen/office areas in any of the commercial complexes, and consequently no need for garbage disposals. Therefore, there should be no highly concentrated organic loading. The characteristics of the wastewater flow will be predominately blackwater from toilets, with a comparatively small volume of graywater from sinks, showers or other sources of graywater. Additional wastewater constituents may consist of coffee,juices or other similar type liquids to the system. There should be no industrial or commercial chemicals, solvents, etc. introduced into any of the septic systems. 4 Chesney Consulting