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J. E. STOVER & ASSOCIATES, INC. P. O. BOX 60340 GRAND JUNCTION, COLORADO 81506 PHONE: (970) 245-4101, FAX 242-7908 MINE ENGINEERING MINE RECLAMATION August 1, 2006 RECEIVED Dan Mathews AUG 03 2006 Division of Minerals and GeologyG;~;$,o„o,M,~~ISe~tlG~, 101 South 3`d Suite 301 °~ Grand Junction, CO 81501 Re: Snowcap Coal Company July 20~' Rainfall Event Permit C-81-041 Dear Mr. Mathews: CIVIL ENGINEERING CONST. MANAGEMENT On July 20~' there was a significant rainfall event at the mine site. The ensuing run-off caused damage over a wide area of the site. The major damage occurred to the upper diversion ditches of the Roadside and Cameo No. 2 refuse disposal areas. Riprap in the steep section of the Roadside refuse disposal area upper diversion ditch failed. Water eroded the ditch bank in two locations so some of the flow was not contained in sediment pond 9. The Cameo No. 2 refuse disposal area upper diversion ditch was clogged with sediment however, the ditch continued to function. It appears all run-off was diverted around the pile and therefore the refuse pile was not damaged. The outlet ends of the upper division ditch were eroded by the run-off. The Operator's rain gauges were not functioning during the rainfall event. To determine the size and intensity of the event, the Operator talked to numerous nearby residents. They were unanimous in their characterization of the storm as the most significant rainfall event they have witnessed. One of the residents (Steve Erikson) had a rain gauge. His house is located immediately above the Roadside refuse disposal area borrow pit. On July 28~' Mr. Erikson informed this office he recorded 1.75 inches of rainfall in approximately 1.5 hours. On July 20~' the national weather service issued a warning at 5:55 PM stating Doppler radar indicated a strong thunderstorm developing just north or Cameo. The warning went on to say the storm has the potential to produce heavy rain, frequent lighting, and pea sized hail. The warning expired at 6:35 PM. The same weather pattern caused flooding and road damage in Delta at about the same time the storm hit the mine site. Two and a half inches of rain was recorded in a 20 minute period in a rural area north of Delta (Delta County Independent, July 26, 2006).