REP45988

• Permit No: C1981041
• IBM Index Class Name: Report
• Doc Name: 1994 Annual Hydrology Report & Mine Inflows Study
• Annual Report Year: 1994
• Permit Index Doc Type: HYDROLOGY REPORT
• Media Type: D
• Archive: No

• 1994 Annual Hydrologic Report
Page 5
piezometers to assess potential stability problems. Slight bends
in the ~" diameter pvc pipes prevented monitoring on a few of the
piezometers this Year. Modifications have been made to the water
level probe to handle the bends for future monitoring. No problems
were noted in the water levels related to stability.
The results of water level measurements at the unit train loadout
this Year are listed on Data page GB-1. Diagrams G94-11 thru 14
are graphical representations of water level elevations in these
piezometers. Tables G94-4 and 5 were prepared to show statistics
on these water levels corresponding to high and low flows in the
adjacent river. All of this Year's readings were lower than the
average for the site. These averages may not be a true
representation of the statistics for the sites due to the sharp
change in water level measurements before and after the end of 1986
when monitoring personnel changed. Data pages GD-9 contains the
result of full suite water analysis done on UTL-02 and 04 during
the Year. Diagrams G94-15 and 16 are trilinear representations of
these water analysis. The circles on the Trilinear diagrams
• indicate a relative amount of TDS, the larger the circle the higher
the TDS. The upper site had a higher TDS than last year and the
lower site had a lower TDS.
A former mine dewatering hole located at the North Decline area of
the mine is now being used to monitor the water level in the
abandoned portions of the Roadside South Portal. It is monitored
primarily to keep it within a 10' zone between the bottom of the
siphon for outfall 002 and the reclaimed Northwest Intake Portal.
The results of monitoring are include in the Mine Water section,
Table M94-3.
MINE WATER
The annual mine inflows study for this year was taken the end of
September 1994 and again is being made a part of this AHR. The
results of the study are given on data pages MA-6 thru 8 and MB-8.
A summary of past conductivity and flows from the monitoring
locations are given on Tables M94-1 thru 5. Inflow monitoring
locations are shown on the 1994 Mine Inflows Map.
As usual there are many differences in the monitoring results at
the Roadside South Portal. These differences are primarily the
result of changes in mining locations; differences in water
routing, piping and pumping patterns; and general difficulties
involved with monitoring underground. Locations 3 and 23 showed
• little sign of surface irrigation, possibly due to a lower
availability of water for irrigation this Year. Locations 24 and
25 continued to be large contributors this year but 25 was
considerably lower than last year. Flow measurements at 5, 10, 14