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<br />lazge diameter water pipeline across the North Decline reclaimed area within their right of way, and is
<br />responsible for reclahning the disturbance corridor through agreement with Powderhom.
<br />Details of these facilities and various roads and support facilities is summarized in Table 12-1. Total
<br />disturbance area is 242.6 acres.
<br />The reclamation plan is presented in Tab 14, Volume 5 of Ute permit application document, wiUt details of
<br />reclamation for specific areas beginning on page 145. A tJvee year reclamation plan timetable is presented ,
<br />in Figure 14-1, of Tab 14. Note that, per the initial paragraph on page 14-1 of Tab 14, the start of
<br />reclamation "Yeaz 1 may be up to 1 year past Ute end of final shut down to allow for final engineering,
<br />permitting and job bidding." Powderhom Coal Company (PCC) notified DMC Utat mining had ceased at
<br />the Roadside Portals Mine on December 2, 1999, by letter of December 13, 1999. Notification That Ute
<br />operational cessation was permanent, was provided by letter of March 13, 2000. Depending on how "final
<br />shutdown" is interpreted, "Year 1" of the reclamation schedule would begin at some point benveen
<br />December 2, 2000, and Marclt 13, 2001.
<br />Outstandine Issues
<br />1. Permanent Mine Dewatering Plan. During Pemnit Renewal RN-03 review in 1999, the Division
<br />ident~ed a concern wiUt regard to the adequacy of the South Mine dewatering system, for the long
<br />term (i.e. permanent) postmining situation. The primary component of the dewatering plan is a 6 inch
<br />pipe siphon system, which outlets through the "Northwest Intake Portal", an air shaft which was
<br />backfilled in the early 1990's. The siphon discharge is supplemented by a 4 inch dewatering pipe
<br />recently installed through the SouUt Mine portal seals. This pipe intercepts approximately 75 gpm
<br />from sumps upgmdient in the mine, and discharges through CDPS Discharge 001 into the river.
<br />The reclaimed Northwest Intake portal is located immediately adjacent to and up-slope from I-70,
<br />between the South Portal Facilities Area and the Nortlt Decline. It is downgradient from Ute South
<br />Portals. The dewatering pipe passes beneath I-70, Uuough a highway deparunent culvert and
<br />discharges directly into the river. The site is CDPS Discharge 002. Discharge is typically on Ute order
<br />of 200 gpm, and has historically met CDPS disclutrge limits. Primary concerns identified by the
<br />Division related to the fact that Ute system requires regular monitoring to insure that water level in Ure
<br />mine remains vviUtin a certain range, for the siphon to function properly. The company monitors w.ver
<br />level via Well N-I, at the North Decline, and maintains water level within Ute specified range by
<br />adjustment of the valve at the 002 outlet. If the siphon pipe iNct should become blocked, or the siphon
<br />should otherwise cease to function, water levels would gradually rise to Ute level of Ute sealed
<br />Northwest Intake Portal. The sealed portal would be the most likely location where minewater would
<br />discharge. It is unclear wheher this discharge would initiate shortly following water level reaching Ure
<br />portal elevation, in a non~atastrophic manner, or whether water levels and pressures would buildup
<br />for some period of time, ultimately releasing in a highly visible and potentially catastrophic "blowout"
<br />of floodwater and debris onto I-70 and into Ute river.
<br />The operator wmmitted within the permit application, to perform an evaluation and submit any
<br />necessary revision to Ute sealing/discharge plan by June 30, 2000. in a letter of Febnrary 17, 2000,
<br />The Division directed the operator to submit a minor revision "interim minewater discharge plan' and
<br />a teclmical revision "permanent rninevvater discharge plan". The permanent plan was to be submitted
<br />by June 30, 2000, and was [o include, in addition to outer items, a description of "tlte worst case
<br />consequences of failure...".
<br />The interim plan, which includes the recently installed 4" dewatering pipe Uuough Ute sealed South
<br />Portal, was approved via MR~I, on March 22, 2000. Technical Revision 33 permanent plan was
<br />received by Ute Division on Jtme 21, 2000. The plan as subtnined proposed no modifications to Ute
<br />current system for permanent discharge. Possible alternatives, including horizontal drilling beneath 1-
<br />70 into the lowest portion of the workings, or re-opening Ure Nonlnvest Intake Portal to install gravity
<br />discharge pipe(s) were rejected. No evaluation of the worst case consequences of failure was provided.
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