2013-10-07_REVISION - C1981025 ‎(8)‎

• Permit No: C1981025
• IBM Index Class Name: Revision
• Doc Date: 10/7/2013
• Doc Name: Proposed Decision and Findings of Compliance
• From: DRMS
• To: Minrec Inc
• Type & Sequence: RN6
• Email Name: BFB
• Email Name: SB1
• Media Type: D
• Archive: No

rights holder, North Thompson-Four Mile Mineral (NTFM), uses all the water for
irrigation and livestock. NTFM is active in preventing any water loss to North
Thompson Creek. WQCD is currently reviewing the permit to determine if a
CDPS permit is still necessary. No decision has been made as of the decision date
for RN-6.

B.Surface and Ground Water Monitoring

The last remaining piezometers monitoring ground water were Phase III bond
released in SL-6. No ground water monitoring program is currently in effect.

C.Stream Buffer Zones

Pre-law surface or underground mining activities within 100 feet or through
perennial streams or streams with a biological community within the permit areas
were recognized in the PAP. The approved reclamation plans included restoration
of original stream channels, a requirement that water quality and quantity shall not
be adversely affected, and a requirement that appropriate riparian vegetation was to
be reestablished. Recognized pre-law areas of disturbance are at Portal 1 and
Portal 1 facilities areas, the underground workings beneath North Thompson Creek
and the conveyor over the Roaring Fork River. The coal mine waste pile and pond
and four water monitoring flumes were permitted (Rule 4.05.18(1)).

D. Probable Hydrologic Consequences

There is no known underground mine water discharge from North Thompson
Creek Mines in the Middle Thompson Creek drainage. There are no known
impacts to groundwater in the Middle Thompson Creek drainage from mining and
reclamation activities or to the Roaring Fork River from the loadout site.

1)Ground Water

Current discharges indicate that both the North Thompson Creek No. 1 and No. 3
Mines are experiencing mine inflows. The mine portal discharges represent a
redirection in the migration of groundwater from pre-mining conditions. Inflow
maps, descriptions of inflows and water quality analyses of inflows applicable to
periods of mining are within the PAP. The inflow water quality analyses indicate
that there may be at least two sources of water. The inflows with low total
dissolved solids (TDS) concentrations have water qualities similar to surface
waters. This suggests that these inflows may be transmitted directly to the mine
workings from the surface water system with very little residence time in the
transmitting aquifer or are emanating from aquifers with few dissolvable solids.
These low TDS inflows are also generally found emanating from fractures beneath
or directly adjacent to the stream valleys of North and Middle Thompson Creeks.
High TDS inflows are thought to indicate longer residence time and reactive time
with soluble minerals in the transmitting aquifer. These inflows may thus

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