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• Recharge capacity is expected to increase. The potential infiltration rate will increase due to the increased porosity of the backfilled overburden and soil in the pit area. Recharge is expected to fill from the pit bottom above the Pictured Cliffs Sandstone aquitard to the water-bearing zones which will accept the water and transmit it down dip and laterally to the assumed sink, the Animas River. The water is moving primarily through fractures in the coal along the 21 to 28 degree down dip. The grade, laterally, of the Pictured Cliffs Sandstone is only about four degrees from the pit area to its outcrop near the confluence of Carbon Junction Canyon and the Animas River. The outcrop sandstone and associated channel bottom are dry which supports that hypothesis that the sink is occurring downstream where the water-bearing zones intersect the Animas River. Thus, runoff will decrease and ground water recharge will increase. Once equilibrium is attained, no net change in water quantity reaching the Animas River is expected. Any coal processing waste will, to the extent possible, be placed above the water- bearing zones in the pit; which will minimize the time water will be in direct contact with the processing waste. Based upon ground water quality analyses, overburden analyses and coal reject analyses; no increased adverse effects on long term ground water quality are expected. Revegetation, as planned, will reduce long term sedimentation of the disturbed area. No other adverse effects are expected. Oakridge will conduct a spoils monitoring program as a part of the protection of the hydrologic balance in the reclamation program. The spoils monitoring will begin with spring runoff in 1998, and extend until such time as no discernible change in water character occurs for three consecutive quarters. A single monitoring point will be established at the base of the spoil at the lower end of the underdrain. If there is a water discharge from this monitoring location, it will be monitored as a spring under the spring and seep survey. Monitoring of the spoil dischazge will occur semi- annually. In the event other springs develop, the spoils monitoring program will be amended to incorporate analysis of these features as necessary. 2.05.6(4) Protection of Public Parks and Historic Places There aze no public pazks or historic places neaz the mine site. 2.05.6(51 Surface MininP Near Underground MinioP There are no underground mining activities near this surface mine. 2.05.6(61 Subsidence Survey. Monitoring, and Control Plan The requirements of this section do not apply, Carbon Junction is a surface mine. • Technical Revision 08 (v 1.4) 5-37 Revised 9/1997