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D. GROUNDWATER INFORMATION Groundwater elevation measurements were taken by Mr. Curtis on February 13, 1999 and determined to be 7 ft. 06 in. from existing grade. The static water level in this test boring was measured again on February 16 and found to have risen to 6 ft. 04 in. below existing grade. On April 26, 1999, the backhoe test pit revealed the phreatic water or the zone of saturation to be at 10 feet below existing grade. Upon entering this zone, groundwater poured into the test pit as if under pressure. There are two explanations for these measurement discrepancies. First,the groundwater level measured in February may have been attributed to winter rainfall. Soil water, referred to as vadose water, may have been the contributing factor to this measured groundwater level. Secondly, from direct observation, the groundwater is under pressure probably due to the confining clay soil above the phreatic water. Once this zone of saturation was entered with the hand auger, the confining pressure caused the static water level to rise to the 6 ft. 04 in. measurement. To determine the possible nitrate impact from the subject leachfield, groundwater was sampled from two backhoe test pits. These test pits were excavated by the operator who installed the septic system, so he was familiar with the leachline location. One pit was dug upgradient from the leachfield and one pit was dug downgradient from the leachfield. Groundwater gradient was determined by the topography of the land surface which declines toward the northeast as illustrated on the attached USGS map. Groundwater normally follows the contour of the land surface, particularly when there is a sizable difference in elevation. Two constituents were analyzed to determine potential impact from the existing septic system. These two constituents are chloride and nitrate and can be indicators of septic contamination. It is well known that nitrate and especially chloride travel easily through the subsurface soil environment. Chloride is usually the first indicator of septic contamination, however, high nitrate together with high chloride is a more positive indication of septic impact. From the Water Analysis Report found in the Appendix, it is noted that contamination has apparently already occurred from the Temple's septic system. Both downgradient concentrations of nitrate and chloride show elevated levels in comparison to the upgradient concentrations, and in fact are above the MCLs. Analysis of the on-site domestic well water shows a medium concentration for both chloride and nitrate, at 316 ppm and 28 ppm, respectively. E. SURFACE WATER INFORMATION There is no body of surface water in the proximity of the septic system which may be impacted from septic effluent. 3 `Dalley Aq Ppearch