REP00916

• Permit No: C1981041
• IBM Index Class Name: Report
• Doc Name: 1998 Annual Hydrologic Report & Mine Inflows Study
• Annual Report Year: 1998
• Permit Index Doc Type: HYDROLOGY REPORT
• Media Type: D
• Archive: No

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The seeps in the north mine area were all checked on May 31,1998 and found to be dry.
Rocks in the areas were wet but the flow was too low to measure.
DISCHARGE IPOINTS
There was no discharge from CDPS discharge points 005 through 014 during the Year.
Discharge point 001 is an overflow to a mine water system for the preparation plant. The
source of the water is primarily location 3 in the Roadside South Mine but can include flow
from location 5. Flow from this site is not directly related to inflows and is discussed in
more detail in the Mine Water section of this report. As with other winters, in order to avoid
freezing problems only enough water to supply the preparation plant was pumped from the
mine. Page SD 12 shows the results of weekly monitoring on this point. The 1998 full
suite analysis is shown on Page SNP. Historic data trends tracked by Peabody Western's
hydrologic reporting system from the 1997 Annual Hydrologic report are included.
Powderhom no longer has access to this program but includes these items to show historic
trends since '1979. Diagram S97-1 is a graph relating TDS to time and incorporating a
Lowess Smooth Plot using a "nearness" factor of 0.5. All discharges from this site were
within the permit limits.
Discharge point 002 is water siphoned from the former NW Intake Portal of the Roadside
South Portals. Mine inflows not used underground or pumped to the preparation plant are
routed to an abandoned portion of the mine for discharge from this point. Flow information
for this site is in the Mine Water section of this report. Page SE-7 shows the results of
water quality monitoring peformed at this site during the Year. Data page SOS is a full
suite analysis performed on a sample collected during 1998. The average TDS dropped
again this Year. The following table presents the average TDS measurements for outfall
002 for the last four water years.
Average TDS from Pages SE-3 - SE-7
Water Year 1995 1996 1997 1998
TDS (mg/l) 1767 1709 1683 1673
Table S97-3 gives the historic data trends at this site since 1979. Diagram S97-2 is a
graph relating TDS at outfall 002 to time prepared to incorporate a Lowess Smooth Plot
(nearness = 0.5). The source of water for this discharge point has varied over time.
Information prior to December 1992 may not be representative of future trends.
AHR 98 Page 3 rr1-99