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West Elk Mine
<br />sedimentation ponds MB-1 or MB-2R for treatment, if necessary, and is discharged into the
<br />receiving streams or to temporary storage in various sumps within the mine. The changed timing of
<br />these return flows to the receiving streams is of no practical consequence, because the inflows via
<br />fault systems far exceed the losses (or consumptive uses) to the North Fork. In addition, the mine
<br />inflows are a new, non-tributary source of contributions to the North Fork. Similarly, because
<br />losses within the mine are roughly 5 percent of the total inflow, the annual loss will be 1 acre foot or
<br />less. It is also important to recognize that at those times when inflows (other than those from the
<br />fault systems) to the mine are likely to be at their highest levels during snowmelt runoff, water users
<br />in both basins .should be satisfied rather than "calling" more junior water rights users out of the
<br />stream.
<br />Streams
<br />Baseline data for streams in and adjacent to the permit area are being obtained as presented in
<br />Section 2.04.7 and, more specifically, in Table 4 of Exhibit 71. Drainage basins and the resources
<br />monitored or proposed for monitoring are shown on Map 34.
<br />Monitoring to determine the hydrologic consequences to streams is by seasonal measurements
<br />(three times per year to correspond to the start of spring runoff, the peak spring runoff, and the fall
<br />low flow) of flow, pH, conductivity, and temperature are taken. Seasonal samples are also obtained
<br />from the Sylvester Gulch and North Fork sites for analysis of of total dissolved solids (TDS), iron
<br />(Fe), manganese (Mn), and total suspended solids (TSS). Annually during the second sampling
<br />(except for the North Fork which is during the third sampling), MCC performs a full-suite
<br />laboratory analysis including TDS, TSS, calcium, magnesium, sodium, SAR, hardness, bicarbonate,
<br />chloride, nitrate/nitrite, phosphate (P02-3 as P), sulfate, Fe (total & dissolved), Mn (total &
<br />dissolved), aluminum (dissolved), arsenic (total recoverable), cadmium, copper, lead, mercury (total
<br />recoverable), molybdenum, selenium (total recoverable), and zinc.
<br />A seasonal, rather than quarterly or semi-annual water quality monitoring schedule was instituted
<br />for a variety of reasons. The primary reason for selecting seasonal sampling is that, in many
<br />instances, particularly streamflow and spring flows, these are the only periods of measurable flow.
<br />Most of the streams are ephemeral or intermittent at best, and nearly all of the springs are ephemeral
<br />except in the wettest years. Nine years of baseline data clearly indicate that there is no reason to
<br />attempt to sample these locations in the dead of winter. The adverse conditions encountered in the
<br />remote areas of the West Elk Mine lease area severely hamper sampling procedures and influence
<br />the collection of meaningful data. As a result, by restricting sampling to the periods of flow and
<br />ensuring sample integrity, MCC is better able to provide meaningful data to the agency while
<br />reducing the costs associated with collecting unnecessary data or data that is not meaningful.
<br />MCC has selected the water quality parameters above and in Table 4 of Exhibit 71 for routine
<br />measurement because they are most commonly associated with coal mining impact on water
<br />quality. Annual full-suite monitoring will allow MCC to identify possible mining-induced changes
<br />in water quality. Monitoring data, along with a discussion of any impacts observed or projected,
<br />will be provided in an Annual Hydrology Report to be submitted by June 30 each year.
<br />2.05-294 Rev. 06105- PR10; 03106- PRIO; 05106- PR10; 05109- TR117
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