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Elk Mine • to 90 gpm); G-31 (up to 45 gpm) in Gribble Gulch; and D-2, J-4 and J-10 (up to 30 gpm) all in the Apache Rocks permit revision azea. The range of flow data is presented in Exbibit 57 and in Annual Hydrology Reports. Fifty springs/seeps have been identified in the South of Divide permit area. Most of the springs/seeps have negligible yield. Only four of the springs have been identified as perennial (WCC-24, J-7, J-2, and 35-3), of which only J-7 is within the area of mining influence. Most springs in the lease block derive their water from perched aquifers in the coluuvium and Barren Member of the Mesaverde Formation. The fact that most springs dry out during the late summer indicates that the groundwater reservoirs supplying the springs are limited in extent. The dischazge rates of the springs respond closely to precipitation events, another indication that the rechazge azeas for the springs are very localized. There aze three different types of springs within the pemut area: 1. Alluvial Springs -Subsurface water moving through the alluvium emerges as a spring, and discharges into the drainage channel. 2. Colluvial Springs - Cllluvial groundwater moving downgradient emerges from the colluvium as a spring. The source of the goundwater in the colluvium can be snowmelt infiltration, rainfall infiltration, dischazge from a surface channel or upgradient bedrock spring flows that infiltrate • into the colluvium. 3. Bedrock Springs - Springs can be encountered where subsurface formations outcrop. Groundwater moves along the surface of the formation and eventually daylights. Historic Spring Monitoring_Data Spring monitoring to establish baseline data and to assess the impacts of mining in the F Seam has been conducted by MCC for over 10 years. Monitoring of springs potenfially subject to impact from B Seam mining has been conducted since 1992. The relevant data indicate that F and B Seam mining has had little, if any, impact on spring flows. Specific information on spring-related mining impacts for these seams can be found in the Annual Hydrology Reports from 1982 to the present. Plots of spring flow hydrographs are contained in the Annual Hydrology Reports. Considerable variation from yeaz to year is also apparent along with the seasonal pattern. A comparison of operational data with pre-mining data reveals no discernable difference. Flow monitoring will be continued by MCC in order to assess trends over time. A visual comparison of the data presented in the Annual Hydrology Reports reveals a lack of correlation among spring flows. MCC has been building a representative database for springs in the permit and lease areas, since 1978. Sufficient baseline data, in accordance with CDMG regulations have been established to enable future detemunations as to whether longwall mining could be affecting the springs. 2.05-16$ Revised November 2004 PRl0