GENERAL40417

• Permit No: C1981025
• IBM Index Class Name: General Documents
• Doc Date: 8/12/1993
• Doc Name: PROPOSED DECISION & FINDINGS OF COMPLIANCE FOR RN2
• Permit Index Doc Type: FINDINGS
• Media Type: D
• Archive: No

Monitoring wells Dl-A and D2-A at the base of the refuse area
are to be monitored for water level, pH, electrical
conductivity, and temperature. The sampling frequency for the
ground water monitoring wells is quarterly.
The No. 1 and No. 3 mine discharges, NPDES discharge points 001
and 007, respectively, will also be monitored. According to
the NPDES permit, discharge point 001 will be monitored weekly
for flow rate, pH, and oil and grease, monthly for TSS and
total recoverable iron, and quarterly for TDS. Discharge point
007 will be monitored monthly for flow rate, pH, oil and
grease, TSS and total recoverable iron, and quarterly for TDS.
2. The applicant will conduct monitoring of surface water in a
manner approved by the Division. The monitoring plan was
submitted under 2.05.6(3>(b)(iv) and includes the following
(4.05.13(2)):
Two sites, one upstream and one downstream of the mine area,
will be sampled for TDS, pH, Ca, Fe, Mn, SOq, TSS, HC03,
Cl, Mg, Na and Zn. The sampling frequency for surface water is
biannual.
E. Stream Buffer Zones
The Division approved surface or underground mining activities
within 100 feet or through a perennial stream or stream with a
biological community. This decision is based on a finding that
the original stream channel will be restored, water quality and
quantity shall not be adversely affected, and appropriate
riparian vegetation will be reestablished. The buffer zone
variance is granted for the area where the pre-law adit between
portals No. 1 and 2 undermines North Thompson Creek
(4.05.18(1)).
F. Probable Hydrologic Consequences of North Thompson Creek Mine
Ground Water
The North Thompson Creek Mines
quality of ground water in the
drainage basins. These impacts
are impacting the quantity and
North and Middle Thompson Creek
are minimal, at present.
Both the North Thompson Creek No. 1 and No. 3 Mines are
experiencing mine inflows. The inflow maps, descriptions of
inflows, and water quality analyses of inflows are within the
permit document. The inflow water quality analyses indicate 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 inflo.+s
may be transmitted directly to the mine workings from the
surface water system with very little residence time in the
transmitting aquifer. These low TDS inflows are also generally
found emanating from fractures beneath or directly adjacent to
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