PERMFILE104233

• Permit No: C1981038A
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Section_Exhibit Name: ENVIRONMENTAL RESOURCES - FISH & WILDLIFE APPENDIX
• Media Type: D
• Archive: Yes

Fran historical detailed coal sampling at the face and on the surface, an
• approximate 1% moisture gain from the in-place value to the train loadout
point is apparent. Consequently, at the 1.5 million ton per year
production rate, approximately 3,750,000 gallons per year would be
aksorbed into the coal which is shipped fran the mine. 4he remaining
5,625,000 gallons imported into the mine under this scenario is lost
thrax~r floor and rib absorption, and ventilation consumption.
Coal Processing Consumption-
Zhe Orchard Valley Mine has no coal preparatory plant and consequently, no
streamflow depletion results. Spray bars are utilized at various points
in the oval handling system and may contribute slightly to depletions.
Zhese depletions are accounted for in the metered mine withdrawals at the
sources of the mine water.
sr~rt;nwr,t Pond Evaporation:
Nine sediment ponds exist on the mine property. Potential depletions can
occur from these ponds as a result of evaporation although the majority of
the ponds are typically dry for most of the year. 'Ihe total surface area
of the ponds as moa~~red at maximinn water level is 63,959 feet or 1.47
acres. ~lirough consultation with the Soil Conservation Service in Delta,
Colorado, and the Division of Water Resources office in Montrose,
Colorado, a factor for determining evaporative water lass as a function of
pond surface area was obtained. Studies conducted by the Division of
• Water Resources have determined that approximately 3.125 acre-feet of
water per acre of pond surface area per year is last to evaporation. For
the Orchard Valley Mine, this translates to an evaporative loss of 4.6
acre-feet of water per year.
Subsidence Effects on Springs and Seeps:
An extensive hydrology monitoring network is established within and around
the Orchard Valley Mine permit area and is utilized to detect mining
impacts to surface water features (porxls, springs, irrigation ditches, and
streams) within the area of potential mine influence as projected
utilizing angle of draw. To date, no mine related impacts have been
detected by this network. In the event impacts become apparent at any
particular feature, CDVCC is required to restore the feature by
implementing repair procedises which are specified in the mining permit.
Selected zones within the permit area are restricted to limited mining and
are thereby protected from subsidence inducing development which could
potentially disrupt or impact surface water regimes. No permanent
streamflow depletion is anticipated to occur due to subsidence effects.
Mine Inflows and Outflows:
Mine inflows at the Orchard Valley Mine occur when mine workings intercept
saturated, discontinuous, perched aquifers. Inflow events are typically
minor and sporadic and total mine inflows experienced to date have been
less than 1,000,000 gallons per year. No water is discharged from the
• Orchard Valley Mine and therefore no inflow water is subject to loss
through evaporation during retention in ponds. Inflow water encountered