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Rmdside }iinc :~l'1:1malIVV IsSUes
<br />~e••ember 8. 2000
<br />Pa_e
<br />V
<br />On August , 1.2000, Dan Mathews and 1 met with Tanya Hammond and you on-site, to discuss certain rcclamanon
<br />issues. With respect to CRDA ?reclamation, we recommended the grading plan for the cop of the pile be amended to
<br />include a substantial topographic barier to intercept floodwater and debns flow, and divert such flow away from the
<br />long. steep refuse ourslopes, should the proposed upland diversion ditch fail. Final recommendations retarding the
<br />Coal Creek channel and culvert reclamation were not made. pending further discussion with BL~I. On September 3.
<br />'_000, I met with Brvice Fowler and Jim Scheidt oC BLhI, and again visited the site. A summary of my observouons
<br />and discussions with the BLM representatives is provided in a memorandum of September 21, 2000. a copy of which
<br />w~az sent to you. The memorandum includes detailed recommendations re_arding final reclamation designs fos the
<br />permanent channe! and culvert structures.
<br />On Vovembe: ~, 2000, DMG received from Powderham amended reclamation plans addressing de5cienctes
<br />identified and recommendations made by DMG, and those plans are currently under review.
<br />Technical Revision fTR133; South Mine Permanent De-waterin3Plan
<br />During Permit Renewal RN-03 review in 1998 and 1999, the Division identified a deficienty with regard to the
<br />adequacy of the South Mine de-watering system, for the long term (i.e. permanent) post-mining situation. Tne
<br />primary component of the de-watering plan is a 6 inch pipe siphon system, which outlets through the "Northwest
<br />Intake Portal", an air shaft which was backfilled in the early 1990':. In order for the siphon to function properly,
<br />perpetual monitoring of the water level in the mine is required. If the siphon does not funttion properly, ware: levels
<br />would rise to the level of the backfilled Northwest Intake portal, likely resulting in uncontrolled discharge, with the
<br />possbility of a catastrophic "blowout" that resold create a hated on interstate Flighway 70, located adjacent to and
<br />dawn•gtadient from the portal.
<br />DMG requested the operator to provide pertinent information regarding hydrologic conditions and the existing
<br />discharge system, az well az proposed modifications to address permanent discharge, in adequacy review levers dated
<br />February 12, 1998, April 14, 1999, and December 3, 1999. in response to the Division'sconcern, the operator
<br />provided the requested hydrologic information and devils of the existing discharge system, and commired within the
<br />permi[, to submit plans for a permanent mine-wamr discharge plan by Junc 30, 2000. In a lever of February 17, ?000,
<br />the Division d'treaed the operator to submit a minor revision application "interim minewater discharge plan" and a
<br />technical revision'~ermanent minewazer discharge plan". The permanent plan was to include, N addition to other
<br />items, a description of the worst case consequences of failure. The interim plan, submitted az Minor Revision (MR)
<br />a 1, provided for itutallation of an additional 4 incfi de-wauring pipe tfvougft the South Portal seats, upgtadien[ of the
<br />Northwest Intake portal. The MR~I plan waz approved and implemented, and resulrs in approximately 75 gpm of
<br />mine inflow being intercepted and discharged via an approved dischage location, rather than pooling at the lowest
<br />elevations in the mine. This additional 4 inch pipe supplemenes the siphon system, but does not alleviate the
<br />deficiencies of the siphon sysum az a permanent solution, which are described in the previous paragraph.
<br />Powderhorn submired a proposed permanent minewater discharge plan az TR-33, on June 21, 2000. The phtn az
<br />submired proposed no modifiptions to the existing'interim de-watering" system, and did not include an evaluation
<br />of the worst case consequences of failure, which had been requested by the Division. Due to the lack of the worst
<br />case evaluation, the revision was deemed incomplete by DMG. The revision waz subsequrntly amended, and deemed
<br />complete on July 12, 2000. In an adequacy lever dated September 5.2000, the Division directed the operator to
<br />provide an amended design which would include provision for a maintenance free de-watering mechanism with
<br />minimal potential for failure. The Division determined the existing de-watering system to be unacceptable due to the
<br />high level of monitoring and maintenance necessary to ensure continued functioning, and the potential negative
<br />consequences to public safety and water quality, should the rystem fail. The operator was requested to submit an
<br />amrnded plan addressing the identified deficiencies by October 5.2000. Powderhorn has (ailed to submit an amended
<br />plan, and must submit such amended plan by November,0, 2000,
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