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Mr. George Lockwood <br /> September 7, 2004 <br /> Page 5 <br /> 3. Additional well installations are recommended up and down gradient of the <br /> facility. <br /> Comment: The explanation to support additional well installations says that flow <br /> direction and water quality may not have been adequately determined with two <br /> years data from nineteen wells due to lack of background data. Prior to installing <br /> additional wells, flow gradient and direction should be calculated, and all data <br /> collected should be included and ruled out as not contributing pertinent <br /> information (i.e., add Specific Conductivity and Total Coliform Organisms). The <br /> addition of two other constituents may provide additional insight to the problem <br /> and enhance the analysis. <br /> City Response: The purpose of the additional monitoring wells would be to <br /> better understand upgradient and downgradient conditions. Data evaluated in <br /> the Status Report indicated that groundwater might be flowing toward the City <br /> property from the west and/or northwest. It would be helpful to have additional <br /> groundwater elevation and quality data from that area to provide confirmation. <br /> This may be significant since nitrate levels in water samples from monitoring well <br /> WSM16 are relatively high. WSM16 is located to the north of the northwest <br /> corner of City property. Data evaluated in the Status Report indicated that the <br /> groundwater to the northeast of City property exhibits relatively high nitrate <br /> levels. A large dairy has been operating in that area for some time. It would be <br /> helpful to have better information about the conditions in that area in order to <br /> assist with the understanding of the origin of the nitrates. <br /> The City has evaluated the Specific Conductivity and Total Coliform Organisms <br /> data. Those evaluations, along with additional discussion of upgradient and <br /> downgradient conditions, will be discussed later in this letter. <br /> 4. Water in the surrounding water bodies is to be monitored for migration <br /> underneath the facility. <br /> Comment: This may be a determining factor and deserves to be ruled out with <br /> additional data. <br /> City Response: The City has followed the recommendation from the Status <br /> Report and analyzed samples collected from surface water bodies located to the <br /> west and northwest of City property. See tabular summary enclosed. The <br /> nitrate concentrations ranged from a low of Non-Detect to a high of 2.7 mg/L. <br /> This indicates that the quality of the nearby surface waters is not negatively <br /> impacting the quality of the groundwater that is potentially migrating to City <br /> property. <br /> 5. Monthly groundwater monitoring has been started to verify large fluctuations in <br /> the nitrate data. <br /> Comment: Minimal information has been presented showing the facility's <br /> nitrogen discharge loading and farming practices. The data that have been <br /> provided tends to support the theory of facility operations having an impact on <br /> groundwater. We do not clearly understand why an increase in data collection <br /> LLOCKWOOD_NPDESPERMIT.DOC <br />