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to erosion until vegetation is established. Erosion of these areas would cause an increase in the amount of suspended soil particles carried by surface runoff. Impairment of surface water of South Paddy Creek from landfill leachate is also a potential problem. Leachate is a mixture of solutes in an aqueous solution leached from waste materials. Leachate could con- ceivably enter a branch of South Paddy Creek if it appeared as seepage from the lower side of the fill. Contaminated runoff resulting directly from working the landfill poses another pathway for surface water degrada- tion. r,rnunrdwatPr Impacts on the groundwater may occur in two forms, depending on site location and fill design. These forms may be as a reduction in recharge from precipitation and surface runoff and/or as a degradation of water quality by leachate and dissolved gases. A reduction of recharge to underlying groundwater would be the result of mitigation measures taken to reduce deep percolation of surface runoff and precipitation from contacting the solid waste. These measures may cause a slight, but negligible, lowering of groundwater levels beneath the site. However, water diverted from the site would reach South Paddy Creek where it would eventually reach the groundwater system downstream from the site. Contamination of groundwater could occur if leachate reaches the water table. The degree of contamination would be determined by the quality of leachate itself. The potential for leachate to reach the water table and the composition of the leachate varies with landfill topography and depth to groundwater. The depth to water table as discussed earlier is around 125 to 135 feet below the present.ground surface or between Elevation 20 to 30 feet below sea level. If mitigation measures, as discussed in the following section, are instituted, groundwater contamination should not occur. The principal concern for leachate generation is not simply which pollutants are released to the environment, but rather the rate at which these pollutants are released. In order to assess the potential of leachate production, a water balance (see Table 7), based on detailed analysis of the existing surface and climatological conditions was performed. This water balance indicates the possibility of leachate contamination of groundwater appears very unlikely for several reasons. First, the study area receives a low amount of precipitation (14.17 inches) in relationship to a much higher factor (49 inches) of evapotranspiration. Secondly, the mitigation measures discussed for design of the site should retain any leachate produced for collection and treatment.