1985-12-22_HYDROLOGY - M1984049

• Permit No: M1984049
• IBM Index Class Name: Hydrology
• Doc Date: 12/22/1985
• Doc Name: HYDROLOGIC EVALUATION PRIDE OF THE WEST TAILINGS POND
• Media Type: D
• Archive: No

that the this condition be well established prior to the
• resumption of milling operations, particularly in view of
the forthcoming promulgation of ground water standards by
the State. It would certainly be to Sultan Mountain Mine's
best interests to be able to provide incontrovertible data
demonstrating the polluted nature of the ground water prior
to their operations.
Baseline sampling should be conducted on a quarterly basis
for at least four quarters; however, water levels should be
measured on a monthly basis. The ground water samples
collected during the course of the tailings pond leakage
study should suffice for the first quarter sampling at those
particular sites.
Sample sites identified with the letter "C" on Figure 15 and
the letters "BC" in Table No. 10 are those locations where
sample data should be collected far inclusion in discharge
permit applications. As the early submission of the permit
application is critical to Sultan Mountain Mine's start up
schedule, it would be impossible to await the acquisition of
four quarters of baseline data at these particular sites. It
is, therefore, recommended that these sites be sampled on
three closely spaced intervals, say one week, to obtain a
representative average. However quarterly baseline sampling
should be continued at these sites. This would be subject to
• permit stipulations, which may require more frequent and
continued sampling of the receiving waters (site 31).
The collection of permit baseline samples of the seepage
pond discharge (site 25) prior to reconstruction of the dike
presents a problem of sampling the several flows described
in the previous section on hydrology. A composite sample,
fractioned on the relative proportion of an estimated of the
volume flow rates at each sample point would be an adequate
solution.
Estimates of volume flow rates should 6e made at the surface
water sampling sites. Parshall flumes are recommended for
sites 20B, 25 and 30. The flow rate at site 31 can be
estimated from measurements availble for the gaging station
at Howardsville,0.5 miles downstream, after deducting the
contribution from the tributaries between site 31 and the
gaging station. A sufficiently accurate estimate of these
contributions can be developed by the use of runoff
coefficients and drainage basin areas.
The routing of the interceptor drain through a portion of
the new tailings pond imposes a baseline and operational
monitoring requirement to demonstrate that water quality has
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