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iii iiiiiiiiiiiu iii 999 Tti SEDI.IE ti'T eGnu ~Eic'~1r 11. r111ViV On February 2, 1985, Larry M. Reschke, P.E., certified the construction of the ~1 Sediment Pond. Mr. Reschke certified that the pcr.d *.aas structurally sound and had the storage volume shown on a drawing attached to his certification. During the 1990 mid- term review for the Blue Ribbon Mine, it was noted that the S4 Sediment Pond did not meet the requirements of Rule 4.05.6(11)(e) & (h). Rule 4.05.6(11)le) requires that the top of the settled em- bankment be 1.0 foot above the water surface in the pond with the emergency spillway flowing at design depth. Rule 4.05.6(11)(h) requires that the minimum top width of the embankment be no less than the quotient of (H+35)/5 where H, in feet, is the height of the embankment as measured from the upstream toe of the embankment. For the s4 pond, H = 5.1 feet, so the minimum to width of the embankment shall not be less that 8.1 feet. On August 14, 1991, maintenance work was performed on the pond to bring it in to compliance with the above Ru_._. The pond embankment was widened to a minimum top width of 9-feet. Fill was placed on the top of the embankment so the top of the embank- ment is at least one foot above the elevation of the top of the emergency spillway. The volume of water storage in the pond was not affected by this maintenance work. Some material was ex- cavated from inside the pond so the sediment volume was increased slightly. I certify that the maintenance work performed on the ~4 Sediment Pond was performed under my direct supervision and that to the best of my knowledge and belief the pond is structurally sound and the pond is now constructed in accordance with the provisions of Rule 4.05.6. ~ James E. ma~y,, • ,er ;~~lFeDate P . E . 19 ?~0 .' ~ E STS' ;'PF'a ' .' ' c~ ~:~~ ? 930 ;~ ~ ~~ ~.c ., ~,' 'v 1 ,'' V'~ yC ~ ' . ~~ x ~ ~ " ,4.1: ;, ....~ i