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In 2006 CDPI~ Construction Permit No. CO-6072272 added monthly DMR reporting of site OOlA. Note that ponds A (former Outfal1001A), and H (former Outfal1009A) were deactivated following Phase III Bond release of the Eckman Park area, and were subsequently removed from the newly amended CDPS permit on January 1, 2003. Coal Fine Dischazee to Foidel Creek On 09/11/06, The TCC surface foreman notified the Environmental Group of an unanticipated discharge of coal fines to Sedimentation Pond E from a broken thickener underflow discharge line. The line apparently ruptured at a T-connection within a manhole neaz the inlet to Pond E, discharging slurred coal fines into the Pond. The discharge went undetected for some time, and as a result, the slurried coal fines built-up in the Pond and discharged through the principal spillway riser to Foidel Creek. The discharge resulted in a notice of violation fromDRMS (NOV CV-2006-006). Immediately upon notification of the discharge, a TCC surface crew was dispatched to the pond to seal the riser by wrapping it with brattice cloth to stop further discharge of coal fines to Foidel Creek. Simultaneously, Environmental Staff proceeded downstream on Foidel Creek to determine the downstream extent of migration of coal fines with normal low-flows in the stream, placing anchored booms at six downstream locations in the stream to filter and capture coal fines to prevent their further migration. Significant coal fines deposition occurred in the firs[ 2,000 feet of the stream from the discharge point. Suspended coal fines (black water) were carried downstream approximately 2.8 miles by normal streamflows to a marshy azea (appears to be a subsided area) in the vicinity of a road crossing of the rail-line behind [he original Ashley Ranch house. There was no further evidence of coal fines migration beyond this point (based on visual turbidity observations). Further, there were no significant water quality impacts noted downstream beyond this marshy azea. Water samples were obtained at both the discharge of Sedimentation Pond E (prior to sealing the riser) and just downstream of the limit of [he visible coal fines migration. The downstream sample was clear. After setting for 24-hours, the coal fines had settled out of the "worst-case" discharge sample from Pond E, resulting in a slightly turbid decant water in the upper portion of [he sample bottle. The initial samples were sent-out yesterday for water quality analysis. The Environmental Staff conducted regular monitoring/sampling of the minor flow at the Pond E dischazge and at several downstream points on Foidel Creek. Analytical data was provided to CDRMS. In compliance with applicable reporting requirements of both our CDPS discharge permit and our Mining and Reclamation Permit, the unanticipated discharge was been reported to the CHPHE-WQCD and CDRMS within 24 hours of [he detection of the discharge. TCC also made initial contact with USACE re: emergency permitting of clean-up activities in the stream channel, and with the Colorado Division of Wildlife re: potential aquatic habitat concerns. It was confirmed that the only material discharged was water, coal fines, and a flocculant. Review of the MSDS sheet for the flocculant and a subsequent conversation with, and a-mail from [he floc manufacturer have confirmed that the flocculant is non-hazardous, non-toxic, and does not have adverse effects on aquatic life. This information has been forwarded to the responsible agencies. Subsequent remediation steps included: I) Isolation, dewatering, and clean-out of the coal fines in Pond E; 2} Reestablishment of runoff treatment capacity for Pond E. Surface crews placed a trash pump near the outlet of Pond E and pumped decant water from the contained slurry back to the thickener. A longitudinal earthen berm was then established in Pond E to accomplish Steps 1 and 2. CDRMS granted field approval to construct the berm as a "pond maintenance" activity. The coal fines were isolated, and allowed to continue to dry-out, with pumping of decant water from the surface. The partially dewatered coal fines were allowed to freeze and then to removed them for disposal on the coal refuse pile. This work was completed in January 2007. 13