Laserfiche WebLink
West Elk Mine 2006 Annual Hydrology Report 37 <br />• 4.4.1 Ponds MB-1 and MB-2R <br />Pond MB-1 collects the Project's surface operations water and diverts storm water runoff. Water <br />from Pond MB-1 can be discharged into either the North Fork or Pond FW-1. Pond MB-2R <br />receives water from surface operations, storm runoff, and effluent from the WWTP. Discharge <br />from MB-2R is typically routed to the North Fork, but can be diverted to Pond FW-1, if necessary. <br />Both Pond MB-1 and Pond MB-2R retain water, so settling of sediment occurs prior to discharge <br />(batch mode). In WY 2006, pond MB-1 had 106.0 ac-ft and MB-2R discharged 174.5 ac-ft of <br />water to the North Fork (MCC, 2007). There were no CDPS Permit exceedences for the discharge <br />water quality from these ponds in WY 2006. <br />4.4.2 Ponds MB-3, MB-4, and MB-5 <br />Ponds MB-3 and MB-4 receive storm water runoff and wash down water from the Project <br />conveyors, silos, and load out facilities. Pond MB-5 collects only storm water runoff. In WY 2006 <br />pond MB-4 collected a small amount of water resulting in discharges of about 1 ac-ft. Water was <br />not discharged from ponds MB-3 and MB-5 in WY 2006 (MCC, 2007). <br />• 4.4.3 Pond FW-1 <br />Pond FW-1 is designed to store raw fresh water from the North Fork diversion intake gallery. <br />Pond FW-1 water is pumped to the WWTP and the Project's domestic water system. If the pond <br />overfills, excess water is discharged back to the North Fork. Water was not discharged from pond <br />FW-1 in WY 2006 (MCC, 2007). <br />4.4.4 RPE Pond <br />The RPE Pond collects runoff from the refuse pile expansion area. In WY 2006 no discharge <br />occurred from the RPE pond (MCC, 2007). <br />4.4.5 Pond SG-1 <br />Pond SG-1 was built to collect runoff during and after construction of the mine ventilation shafts. <br />Discharge from SG-1 is routed to Sylvester Gulch. In WY 2006, about 1 ac-ft of discharge <br />occurred from Pond SG-1 (MCC, 2007). <br />4.5 Mine Water Inflows <br />In WY 2006, only one significant ground water inflow occurred during mining in Panel 20 tailgate <br />area (MCC, 2007). The flows originated from the BEM Fault Zone with total flow between 100 to <br />December 2007 HydroGeo, Inc. <br />