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'! .~ 1 .- s RECEIVED July 14, 2006 JUL ~ 0 2006 Division of Minerals d Gedogy Western Fuels-Colorado Mr. Mike Boulay P.O.Box628 Reclamation Specialist Division of Minerals & Geology Nuclo, Colorado 81424 1313 Sherman St., Room 215 Denver, CO 80202 Telephone 970/864-2165 Fax 970/864-2168 RE: Reporting of an Off Site Surtace Water Discharge on July 10, 2006, New Horizon Mine, Permit Number C-81-008. Dear Mr. Boulay, This letter is to inform the Division of Minerals and Geology that on July 10, 2006 at approximately 1:35pm in the afternoon, an unknown amount of untreated mine water was discharged from the New Horizon 2 Mine at five separate locations and at the same time. The cause of the discharges was do to a short duration severe thunderstorm event. The thunderstorm dropped in excess of one (1.08 to 1.54) inch of rain in a period of approximately an hour of time over the active mine area. The amount of rain fall verses time was collected by two recording rain gauges located at Pond 007 and Pond 009 (See Attachment 1 and 2). It should be noted that the mine received between 0.25 and 0.68 inches of rainfall in the prior 48 hours before the thunderstorm event. The ground was partially saturated before the big event of the 10th and the runoff would have been greater because of the ground saturation. The five active Sediment Ponds at NH2 (7, 8,9,12 and 14) with stood the event and performed as design. However, Perimeter Collector Ditch C1, C11 and C17 were unable to fully contain and transfer the water runoff from their perspective fields to their perspective sediment ponds. Some unknown amount of water breached over the embankments at five separate spots on these ditches and flowed off the permit. Collector Ditch C17 had three breach points and Ditch C11 and C1 had one breach point each, See Attachment 2 for site location and breach points. F:\Eng\DATA\WP\dmg\2006\lOjuly06 off site water discharge with photos.doc page 1