REP13458

• Permit No: C1981041
• IBM Index Class Name: Report
• Doc Name: 1993 Annual Hydrology Report & Mine Inflows Study
• Annual Report Year: 1993
• Permit Index Doc Type: HYDROLOGY REPORT
• Media Type: D
• Archive: No

;~ 1993 Annual Hydrologic Report
Page 3
~~
~~~
Cottonwood Creek. This station, SWGS-05 was installed in
September 1993 near the permit boundary, because mining was
projected to progress past SWGS-02 during the current permit
term. Data pages SG-15, SH-15, SI-15 and SK-1 show the mean
daily flow values for the Cottonwood and Rapid Creek flumes and
data pages SG-16, SH-16, SI-16 and SK-2 present a hydrograph of
the mean daily flows. As usual, the flow in these Creeks is
largely controlled by the City of Palisade, depending upon their
need for domestic water. Also, irrigation water is diverted from
the creeks by private water right holders at various locations.
Flows on the Creeks were up to a more normal flow during 1993.
Table 593-3 was prepared to show the average monthly flows during
the primary irrigation season when low flow in the creeks is
critical. The lack of information for July on SWGS-02 and 03 was
a result of erosion around the flumes during the higher flows
that occurred in June.
There was no discharge from our CDPS discharge points 005 thru
014 during the year. These discharge points cover sediment pond
outfalls.
Discharge point 001 is used as an overflow to a mine water system
for the preparation plant. The source of the water is primarily
location 3 (see the Mine Water section of this report) in the
Roadside Mine but can include flow from location 5. Flow from
this site is not 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 is pumped from the mine. Data page
SD-7 shows the results of weekly monitoring on this point. The
permit renewal called for annual full suite analysis of the mine
discharges. This years results are shown on data Oages SN-1&2.
Table 593-4 has been prepared to give a statistical analysis of
information taken at this site since 1979. Diagrams 593-7 thru 9
are graphs relating pH, Total Iron (TFe) and TDS to time and
incorporating a Lowess Smooth Plot. The TFe and TDS are
continuing to show a slight decrease over time. High spikes were
seen again in the TDS due to renewed irrigation over a limited
areas located near the Roadside portal. Diagram 593-10 is a
trilinear diagram showing the water to be a Na HCO3 SO4 type of
water.
Discharge point 002 began discharging in the middle of December
1992. The water for this discharge point is siphoned from our
former NW Intake Portal. A temporary siphon was started in mid
December and a permanent discharge line and siphon was completed
near the end of the month. Flow information for this site is
discussed in the Mine Water section of this report. Data page
SE-2 is a listing of water quality monitoring performed at this