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C~ <br /> <br />MINREC, INC., BLUE RIBBON MINE <br />1993 HYDROLOGIC REPORT <br />JANUARY 1, 1993 THROUGH DECEMBER 31, 1993 <br />• <br /> <br />INTRODUCTION <br />The Blue Ribbon Mine went into permanent cessation in 1986 and the <br />majority of reclamation was completed that year. A minor amount of <br />grading was done in 1987 on the portal bench to improve drainage. <br />During 1988, 1969 and 1992 portions of the bench cover material <br />slumped and were repaired and seeded. <br />The hydrologic monitoring plan is contained in the permit document, <br />pages 124 and 124a which were revised May 14, 1990 and October 8, <br />1990 respectively. Exhibit H-1 and Z show the various monitoring <br />locations. <br />SURFACE WATER <br />The following table shows the flow, pH and conductivity for <br />upstream and downstream Hubbard Creek by quarter for 1993 compared <br />to the same month averages from 1982 through 1992. ~~ <br />Upper Hubbard Creek Lower Hubbard Creek <br />Quarter Parameter Ave 1993 Ave 1993 <br />1st Flow cfs 20.8 3.0 - - I <br />pH 6.2 8.4 S.1 7.9~ <br />Cond umhos/cm 192 200 218 2601 <br />2nd Flow cfs 29.6 10.0 - - I <br />pH 8.3 8.0 8.3 8.1~, <br />Cond umhos/cm 205 I25 2i6 140 <br />3rd Flow cfs 6.5 3.0 - - <br />pH 8.2 8.4 8.2 8.4 <br />Cond umhos/cm 264 380 280 420 <br />4th Flow cfs 7.1 2.0 - - <br />1 <br />pH 8.2 8.2 8.2 8.4; <br />Cond umhos/cm 197 400 241 380' <br />Sediment pond 005, outfall 001, was the only pond that discharged <br />during the year and it only discharged during March. The total <br />discharge was approximately 0.22 acre-feet. The pH was 8.5 and the <br />conductivity was 1300. The relatively low conductivity indicates <br />that the discharge was a mix of surface run-off and discharge from <br />the underdrains. The discharge involved draining the pond after <br />the spring snowmelt. The last discharge from this sediment pond <br />occurred during the spring of 1989. ', <br />1 <br />