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a, :.~„ <br />AHR Review <br />April 17, 2000 <br />Page 2 of 2 Pages <br />The report is in compliance with this rule. The Division required no written interpretation of the data, <br />but a summary of impacts is provided in the report. Impacts are reported as within the probable <br />hydraulic consequences as presented in the Permit (Report Page 5). The Harvey Gap Reservoir outlet <br />conductivity values of 1999 ranged (507 to 740) above the upper baseline value (Permit, Table 8, <br />page 57 of 500 to 700). Seep values during the year ranged from 921 to 1092 (historic base line <br />values ranged from 900 to 1400). The 1999 conductivity values of samples from the Harvey Gap <br />Outlet Below the Mine (515 to 948) were not with baseline values (600 to 730, Table 8). The <br />prediction was that there would be no water quality impact (Permit, page 63). <br />No explanation has been developed for the higher conductivity values at the downstream (Harvey <br />Gap Outlet -Below Mine) sampling site. The seep from under the dam has greater influence (raises <br />readings) on downstream measurements during low flows. There is no report of any groundwater <br />seeps or surface flows to the Harvey Gap drainage from the mine workings. Specific inspections for <br />this purpose found none. A possible seep (1 gal/1.5 min) was noted on the north side of the drainage <br />with field conductivity values of 520 when they were 450 in the receiving stream (inspection, 16 Mar <br />2000). With values so vaziable and so low, with no visual indicated of effluents from the mine or the <br />vicinity of the mine, with the short period of time over which base line values were obtained, and <br />with the impact of the seep (not related to mining activities) on downstream values of conductivity, <br />the Division concurs with the hydrologic impact assessment of no impact. <br />C:\ WpDOCS\Eastside\ahrrvw99.063.doc <br />CC: Dan Hernandez <br />