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Dan Mathews <br />May 15, 1991 <br />Page 3 <br />M. May 23, 1990: The annual embankment inspection <br />was conducted. Skies were clear and temperatures <br />in the 60's °F. The mine was dry at the time of <br />inspection. There was no evidence of any <br />precipitation within the past few days. <br />N. May 8, 1991: The annual embankment inspection was <br />conducted. Skies were clear and temperatures in <br />the 60's °F. The mine was dry at the time of <br />inspection; however, several rain showers had <br />occurred during the previous week. <br />II. Inspection (05/08/91) <br />A. Crest of Embankment <br />The crest of the embankment is a 60-foot wide roadway <br />used for coal haulage. No signs of stress (cracks) <br />were noted upon inspection of the crest. The roadway <br />and side ditches are well maintained. Safety berms are <br />in place. The side ditches are clean and traverse the <br />entire length of the embankment with no openings of <br />discharge onto embankment slopes. There was no flow in <br />the side ditches on the date of the inspection. <br />B. Upstream Embankment Slope <br />Although vegetation is sparse on the side slopes due to <br />the course and rocky material present in the fill, <br />erosion does not appear to be a problem. No cracking <br />was noted on the slope. Only minimal impounding had <br />occurred over the past year as evidenced by the lack of <br />debris or high water lines on the fill slope. The <br />steel stakes set to indicate the 10-year, 24-hour storm <br />water elevation are in place and in good condition. <br />C. Upstream Channel <br />Flow does currently exist through the rock underdrain <br />of the embankment fill at an estimated rate of 5 to 10 <br />gpm. The flow meanders through a small sediment delta, <br />upstream from the toe of the embankment, into the rock <br />underdrain. The rock underdrain appeared to be <br />functioning properly with no evidence of water backing <br />up in the rocks from the current flow. <br />The highest 24-hour precipitation for the 1990 Water <br />Year was 0.60 inches on June 12, 1990. This is lower <br />than the 10-year, 24-hour event of 1.6 inches. A copy <br />