. fall low flow), for the wells listed in Table 4, Exhibit 71. Although no data was obtained from
<br />monitoring well SOM-38-H-1 in 1994, as it was lost (the casing was pinched, bent or blocked) in
<br />1993, monitoring was successfully resumed in eazly 1995. Monitoring of wells SOM 38-H-2 and
<br />SOM 38-H-3 were discontinued as the casing were apparently sheazed by slide/subsidence activities
<br />(see the 1989 AHR). These monitoring wells have been temporarily capped for potential future use
<br />in monitoring the recovery of piezometric surface following the cessation of mining operations.
<br />The steel casing of alluvial well SG-1 had rusted, was appazently bent, and no longer contained
<br />water, so the well was deleted from the monitoring program in 1995 and replaced by well GB-1.
<br />Due to construction on the east side of the LRP, GP-1 and GB-1 had to be abandoned and were
<br />replaced with GP-6 and GP-7 in 1997.
<br />Wells SOM-2H and SOM-16H are completed in the F-Seam and located in the Minnesota Creek
<br />drainage basin, fairly close to the drainage divide. Monitoring of these wells will be continued to
<br />provide assurance that mining is not having an impact on the Minnesota Creek basin. Additionally,
<br />should Mountain Coal Company be fortunate enough to meet the potential production levels, these
<br />wells are most likely to fall into the azea of potential impact. For all other wells in the Minnesota
<br />Creek drainage basin, monitoring will be discontinued until the summer before mining impacts can
<br />be expected, at which time monitoring of those wells with a potential to be impacted in one yeaz of
<br />mining will be resumed.
<br />Monitoring well JMB-12 was completed (see Exhibit 12) within the Jumbo Mountain tract (Map
<br />34) to monitor the B-Seam in this azea. Baseline data was obtained and was monitored during
<br />mining, and subsequently removed from the monitoring program in 1998, because the bottom of
<br />• the well had been mined through with the B-Seam.
<br />Monitoring wells 96-2-2 and 96-27-1 were completed above and in the E-Seam, respectively,
<br />during the 1996 exploration project. Baseline data collection began in the fall of 1996, The wells
<br />are now in the regular monitoring program as indicated on Table 4, Exbibit 71.
<br />Drill hole 96-1 S-1 was drilled during the 1996 exploration program and was completed as a water
<br />monitoring well in the B Seam. See Exhibit 12 for completion information. Because the well was
<br />venting a significant amount of gas, water measurement and sampling is precluded. The well has
<br />been fitted with a vent to allow de-gassing. In the event that the well discontinues producing gas, it
<br />will be incorporated into the monitoring program.
<br />Seasonal measurements (three times per yeaz to correspond to the start of spring runoff, the peak
<br />spring runoff, and the fall low flow) of water level, well water pH, conductivity, and temperature
<br />will be taken for all monitored wells. For groundwater wells with less than five yeazs of
<br />monitoring data, annually, during the third sampling, afull-suite sample analysis consisting of
<br />pH, conductivity, total dissolved solids (TDS) calcium, magnesium, sodium, SAR, hazdness,
<br />bicazbonate, chloride, un-ionized ammonia, nitrate/nitrite, phosphate (POa s as P), sulfate, iron
<br />(total and dissolved), manganese (total and dissolved), arsenic, cadmium, lead, mercury,
<br />selenium, boron, and zinc. All pazameters will be analyzed for their dissolved form unless stated
<br />otherwise. Once five years of data has been accumulated the laboratory analysis will only
<br />. include TDS, pH, conductivity and iron (total and dissolved). A seasonal, rather than quarterly
<br />or semi-annual well and water quality monitoring schedule was instituted for a variety of reasons.
<br />2.05-75 Revised Dec. 1997 MR208; Revrsed Jan. /999 TR88; Rev. Apri12006 PRIO
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