REP37284

• Permit No: C1981014
• IBM Index Class Name: Report
• Doc Date: 3/25/2004
• Doc Name: 2003 Annual Hydrology Report
• Annual Report Year: 2003
• Permit Index Doc Type: Hydrology Report
• Media Type: D
• Archive: No

Mareh 2004 2003 Annua/ Hpdrola¢y Rrpon •Paxe 4
2.0 GROUND WATER INFLOWS, USE, AND DISCHARGE
2.1 MINE INFLOWS
As previously noted in Section 1.0, quarterly mine inflow moniroring was discontinued after
September 2001 since access to monitoring sites was eliminated when the mine portals were sealed in
December 2001. Mine inflows for 2001, as the last reporting period, were estimated at 5.2 acre-feet,
as presented in Table 1, Mine Water Inflow Summary, For the monitoring locations shown on Figure 7,
Mine Monitoring Locations. These locations were monitored semi-annually during the spring and fall for
each annual reporting period. The 2001 mine inflows represent a decrease from prior years, possibly
due to continuing drought conditions. Review of historic mine inflow water quality monitoring
results from previous Annual Hydrology Reports indicates little variance in inflow water quality over
time.
2.2 MINE WATER HANDLING, USE, CONSUMPTION, AND DISCHARGE
During active operations, water-handling systems in the mine captured most mine water inflows near
their source. Within the mine, captured mine water was pumped to sumps located in Crosscut 32 or
the 1st North Mains, or Elowed by gravity to the mined-out and abandoned west area of the mine.
Water from the Crosscut 32 sump was pumped to the West Mains where it flowed by gravity to the
abandoned west area of the mine. Prior to sealing of the mine, mine water handling activities were
discontinued. Mine inflows will continue within the sealed mine workings and water will accumulate,
initially in the lowest portions of the mine-out workings and gradually rising in other mined-out areas
until a dynamic equilibrium, is reached between mine water inflows and discharge to ground water
systems.
During the reporting period, consumptive water use was limited to minor pond evaporation. Total
consumptive use for 2003 is estimated at 0.25 acre-feet, as indicated on Table 2, Water Balance and
Consumptive Ure Summary. Use of the Corley Well as a water source was discontinued in late January
2001. Due to continuing drought conditions, the only ponds that held any significant quantities of
water during the 2003 water year were Mine Ponds 4 and 5, which partially filled during an early June
series of thunderstorms and held water for 2 to 3 months before drying out. Excluding pond
evaporation, [he source of water for any minor consumptive uses is water tracked to the site fzom
Florence or Rockvale. No water was trucked to the site during 2003. It is anticipated that future
consumptive water use will be limited to pond evaporation from the remaining sedimentation ponds
(Ponds 4, 5, Ll, and L2).
The water balance compares water source withdrawals (previously included any excess mine water
pumped from the mine as well as water withdrawn from well sources) with consumptive use and
discharge quantities. No water was pumped from the mine or withdrawn from on-site wells during
2003. Consumptive use during the reporting period equaled the limited pond evaporation, and no
water was discharged to area streams. Given that there were no mine water discharges during 2003,
the most recent water quality data (2001) for mine water are summarized in Table 3, NPDES Discharge
Summary. His[orically, all discharges were within NPDES permit limitations and all samples
submitted for WET testing from Outfall 004 were in compliance. Given that future consumptive use
is expected to be limited to pond evaporation, no future
discharges of mine water are anticipated.
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