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Mountain Coa! Company 1999 Annual Hydrology Report Wesl Elk Mine <br />• Sampling Methods <br />Monitoring measurements included field and laboratory parameters as identified in Footnote No. <br />2 of Table 4. Static water levels were measured at each well. The field technician then sampled <br />each well the same way each time the well was visited. )n general, the groundwater wells in the <br />vicinity of the West Elk Mine do not exhibit recovery within the time necessary to complete <br />sampling. For this reason, as explained during the 1993 Permit Renewal, three casing volumes <br />of water aze not removed from the wells. Instead, a PVC thief with a brass foot valve is used to <br />obtain samples. The bailer was rinsed with distilled water before and after each sample. After <br />rinsing, the bailer was gently lowered into the water column in the well. The sample was <br />obtained, striving to disturb the well water column as little as possible during sampling and <br />retrieval. Prior to measurement, instruments and equipment were rinsed with distilled water. <br />Field parameters were measured and the water sample was divided into the proper sample <br />bottles, sealed, cooled as appropriate, boxed, and delivered to the laboratory for analysis. in <br />some cases, samples may not be available since there was insufficient water for sampling. This <br />means that there was not enough water to fill the sample bottles, plus provide an additional 300 <br />to 500 ml of sample for rinsing and field parameter measurement. <br />Underdrain and Mine Water Monitoring <br />In addition to the surface, spring and seep, and groundwater well sites, MCC monitors some <br />other miscellaneous flows that aze summarized in Table 6. These miscellaneous flows include <br />monitoring potential flow from the underdrains at the lower refuse pile and the refuse pile <br />• expansion area and mine water inflows. MCC has in the past informally monitored mine <br />inflows, but due to the significant increase in mine inflows and Minor Revision No. 208, now <br />more formally monitors the inflows as described on Table 6 and in the following section. <br />Sampling Methods <br />Monitoring of the underdrains at the lower refuse pile and the refuse pile expansion (RPE) are <br />conducted on a seasonal basis, usually during spring when if there is flow it is more likely to <br />occur. The underdrain at the lower refuse pile daylights just above the sediment ditch at the base <br />of the pile and on the east side of sedimentation pond MB-2R. If there is flow, an attempt will be <br />made to capture the flow before it enters the sediment ditch by creating a step in the channel to <br />facilitate positioning of a container. The underdrains at the RPE daylight into a CMP prior to <br />entering the RPE pond. Flow measurements would be made by the timed volumetric method: <br />where a field technician times the filling of a container of known volume to determine the flow <br />rate. Several measurements would be made and averaged prior to reporting. Field parameters of <br />temperature, pH, and conductivity would be collected and a sufficient sample collected to send to <br />the lab for full suite analysis as described in Table 6. Proper sampling protocol, as described in a <br />previous section, would be followed. <br />Field parameters and water samples were collected from mine inflows that were of discernable <br />flow (>5 gpm) and/or lasted longer than seven days. If the mine inflows are continuous, they <br />will be sampled at least annually. The locations of the mine inflows encountered during WY99 <br />• are shown on Map 1. <br />831-031.510 Page 12 Wright Water Engineers <br />