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Ms. Sandra L. Emrich July 22, 1983 Page 2 D. June 15, 1982: The annual embankment inspection was con- ducted. Weather conditions were favorable, skies partly cloudy, temperature about 65°F. Alight rain had fallen on the evening of June 14th. E. July 18, 1983: The annual embankment inspection was con- ducted. Weather conditions were favorable, skies partly cloudy, temperature about 85°F. The mine area was dry and mine personnel reported that no measureable precipitation had fallen in about one week. II. Inspection A. Crest of Embankment The crest of the embankment is a 60-foot wide roadway used for coal haulage. No signs of stress (cracks) were noted upon inspection of the crest. The roadway and side ditches are well maintained. Safety berms are in place. The side ditches are clean and traverse the entire length of the em- bankment with no openings for discharge onto embankment slopes. There was no flow in the side ditches on the date of the inspection. B. Upstream Embankment Slope Vegetation is establishing slowly due to the nature of the embankment material and grade and orientation of the side slopes. Erosion does not appear to be a problem due to the limited runoff across the slope. No cracking or bulging was noted on the slope. The slope was inspected for a debris line that would indicate impounding of water. None was found and interviews with mine personnel indicate that no water was impounded during the past year. The wooden stake set to indicate the 10-year, 24-hour storm water elevation had been knocked down by animals or snow accumulation and will be replaced with a metal post at the same elevation. C. Upstream Channel The upstream channel was inspected to a point approximately 100 feet upstream of the lowest elevation. No flow was noted in the channel on the day of inspection. No debris line or water line could be found. This indicates that any flows had been transmitted through the structure via the rock fill. A check of the weather records at the Seneca Mine meteorological station revealed that the highest 24-hour precipitation for 1982 was 0.95 inches on April 12, 1982. This compares with the predicted 10-year 24-hour event of 1.6 inches. A copy of the annual precipitation data covering 1982 is attached.