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Mr. Steve Renner June 10, 1987 Page 3 B. Upstream Embankment Slope Although vegetation is sparse on the side slopes due to the course and rocky material present in the fill, erosion does not appear to be a problem. No cracking or bulging was noted on the slope. Only minimal impounding had occurred over the past year as evidenced by debris at the lower upslope toe to the fill. The steel stakes set to indicate the 10-year, 24-hour storm water elevation are in place and in good condition. C. Upstream Channel Flow does currently exist through the rock under- drain of the embankment fill at an estimated rate of 5 to 10 g.p.m. The flow meanders through a small sediment delta at the bottom of the impound- ment into the rock underdrain. Debris lines along the North slope of the upstream channel indicating varying stages of impoundment. The debris lines were well below the steel stake set to indicate the 10-year, 24-hour storage level. No water was impounded at the time-of the inspection. The high- est 24-hour precipitation for the 1986 Water Year was 1.40 inches on October 7, 1985. This is lower than the 10-year, 24-hour event of 1.6 inches. A copy of the annual precipitation data covering the 1986 Water Year is attached. Downstream Embankment Slope Vegetation appears somewhat thicker on this slope than on the upstream slope. Erosion does not appear to be a problem due to the relatively short slope and limited area exposed to runoff. The only significant runoff from the haulroad ditches occurs in a controlled downdrain on the North abutment of the embankment to the "Tie Access Road" culvert. No cracking, bulging, or other signs of stress were noted. III. Results There appears to have been no noticeable change in the embankment structure since the last annual inspection of July 3, 1986. Vegetation is growing on the side slopes.