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Gary A. Reents 3 14 April 1989 boring logs and the two cross-sections across the site indicate that the substrata consists predominantly of sands and silts to at least 95 feet below the ground surface (log of monitoring well 8) . There doesn't appear to be a persistent low permeable barrier to contaminant migration within this interval , though a less permeable silty/clayey layer (less than 5 feet thick) was logged in some borings. The discussion on the seasonal changes in the ground water gradient across the site is informative. The hydrographs developed for each monitoring well all show the same general yearly trend, that has been interpreted as recharge from the seasonal irrigation of adjacent agricultural properties with imported water sources. The local ground water elevation begins to rise in March and declines in September. The three ground water contour maps developed for the site in October 1988 , November 1988 , and March 1989 , demonstrate that the local ground water gradient varies significantly in both magnitude and direction. In March 1989 the flow direction is noted in the report as being southwest, in October 1988 the flow direction is noted as being north to northwest. The report further stipulates that the hydrographs for the cluster wells 7 and 7A seem to indicate that since these graphs are essentially identical that there is no confining layer between these two wells. It is also suggested that based upon the double spiked recharge exhibited by well 11, near the horse pasture, in relation to wells progressively more distant, that the ground water is very sensitive to local conditions. The consultant concludes that until more data is collected it is difficult to determine contaminant migration patterns and that possible reasons for these fluctuations need to be investigated. I concur with this approach and suggest that on-site and neighboring lands' water use patterns be determined and that this information be compared to local ground water gradient fluctuations. It is mentioned in the report that ground water level measurements will be taken weekly. Monthly ground water elevations should be contoured on a site map and submitted to us for review. Though the report notes that the ground water direction across the site in March 1989 was to the southwest, this is not entirely correct. Ground water seems to be migrating towards a potential cone of depression located in the vicinity of the shop area. However, the lack of mgnitorinc ells alone t ��uthprn hn ,nda �� of the property makes this interpretation difficult However, the proposed location of a monitoring wells, in this area, should clarify this situation. If this is a cone of depression a possible cause may be the on-site production well . The transmissivity of the aquifer has been estimated based upon documented regional value of 11, 700 sq. ft./ day. However, a pump test is proposed to determine local aquifer characteristics.