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<br />Ron Thompson <br />Page 2 <br />03/ 16/01 <br /> <br />Although the rate of recovery is slow, data clearly indicates an increasing water level trend. <br />Flooding of the workings is assumed to be underway as mine water discharge ceased in 1996. <br />Inflows to the mine workings likely average about 130 gallons per minute (gpm). Data collected <br />from the GEM-2 well location at the former 3`d North intake fan site returned a measurable water <br />level for the first time in November 2000. This would suggest the mine is flooded to an elevation <br />of approximately 6732 feet above MSL. Sampling difficulties prevented a water sample from <br />being taken. <br />Please ensure to collect quarterly water samples for the short list requirements (p. 2.05- <br />47d) in the year 2001, as well as an annual, full suite sample for GEM-2 and any other <br />GEM sites that return measurable water levels. <br />Initial analysis done by the Division estimated that a measurable water level would likely result at <br />the GEM-2 and GEM-3 sites in May 2000. Review of this analysis during the 1999 AHR review <br />resulted in a revised estimate of complete flooding of the workings, north of Highway 12, in <br />December 2001. The November 2000 measured water level of at GEM-2 fits comfortably <br />between these two estimates. Year 2001 monitoring should help confirm flooding. GEM-1, at <br />the old Jeffrey intake fan site near the mine portal, will be the last site to show flooding, although <br />a small amount of flooding has occurred at this site due to it's location in the mains. The site <br />was measured as dry in 2000. GEM-3 was observed as dry during 2000. <br />Bedrock well water quality sampling requirements were dropped from the monitoring program <br />due to the distance from the mined area. Previous sampling had indicated an improvement in <br />salinity due to gradient reversal caused by mining drawdown. As the mine workings flood, the <br />natural groundwater gradient to the north-northeast will be re-established. Water quality will be <br />monitored in the mine workings through the GEM series of wells on an annual basis. <br />Alluvial water levels, as indicated in wells PAW-5 upstream of the mine and PAW-6 downstream <br />of the mine, continue to show normal variation due to seasonal influences and no impact to <br />alluvial water levels can be identified at this time. <br />Alluvial water quality remains slightly more saline than the surface water which recharges the <br />alluvium, but is within an acceptable range for all known and current uses. Quality changes due <br />to mining are not apparent. <br />Suring and Seea Survey <br />The spring and seep survey was conducted in August in accordance with the approved plan. <br />Spring #1 in Cherry Canyon and springs #2-7 in Alamosito Canyon were dry. Springs #15, #16, <br />and #17 in and near Ciruela Canyon were also dry. Spring #18 in Parras Canyon fell back to <br />levels less than one gallon per minute (gpm) from 20 gpm in 1999. Spring #20 in Santistevan <br />Canyon was measured at 36 gallons per minute. Wet Canyon springs showed variable flow <br />between 0-7 gpm. Springs #26 and #27 were recorded as only a seep. pH and conductivity <br />readings indicate water quality is suitable for livestock and wildlife use. No impacts to springs <br />due to mining are apparent. However, given the apparent drawdown to the overburden and <br />coal seam, there is the potential that spring flows have been reduced or re-located, especially to <br />the north of the mined area. As the water levels recover in the bedrock aquifers, flows in some <br />springs may increase. Most springs are related to isolated perched aquifers in the overburden <br />or shallow rider coals seams that have not been impacted by mining. The primary reason for <br />changes in spring flow are climatic changes, specifically precipitation variation. Dewatering of <br />