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<br />Jerry Koblitz <br />Page 2 <br />August 27, 1998 <br />Analysis of Data and Determination of Impacts <br />Surface Water Quantity and Quality <br /> <br />Two stations on the Purgatoire River are monitored for flow and field parameters <br />on a quarterly basis and water quality on an annual basis. PRS-1 is located <br />upstream of all New Elk mining activities and PRS-4 is located downstream of all <br />mining activities, but upstream of the confluence of the North Fork of the <br />Purgatoire with the Middle Fork. One water sample was conducted at each of these <br />locations in compliance with the annual sample list from Table 28, page 2.05-90c of <br />the permit. A slight increase in average annual flow was recorded at the <br />downstream site, likely due to ground water discharge. The increase is <br />approximately 13% and could be due to flow sampling error and variation. This <br />slight increase in flow is not significant, especially when quality at the downstream <br />site shows a marked quality improvement, from an average conductivity of 276 <br />umhos/cm at the upstream site PRS-1, to 101 umhos/cm at PRS-4. <br />Ground Water Quantity and Quality <br />Flooding of the mine workings continues at a rate similar to what is estimated in <br />Exhibit 8 of the permit application. Water levels, in the three monitored locations <br />which penetrate the mine workings, have increased in elevation an average of 4.9 <br />feet over 1995 levels. <br />Alluvial water levels, as indicated in wells PAW-1 upstream of the mine and PAW- <br />9 downstream of the mine continue to show normal variation due to seasonal <br />influences and no impact to alluvial water levels can be identified at this time. <br />Alluvial water quality remains slightly more saline than the surface water, which <br />recharges the alluvium, but is within an acceptable range for all known and current <br />uses. Quality changes due to mining are not apparent. <br />S~rin,g and Seep Survey <br />The spring and seep survey was conducted approximately one month late, in <br />September rather than in August. Spring flows have been variable over the historic <br />monitoring period and are generally small, having only a localized importance to <br />