Hydrologic conditions and water-quality conditions following underground coal mining in the North Fork of the Right Fork of Miller Creek drainage basin, Carbon and Emery Counties, Utah, 2004-2005

The effects of underground coal-mining-related land subsidence on overlying hydrologic systems generally are complex and poorly understood, particularly when the depth of overburden is shallow (less than 500 ft). From 1988 to 1992, the U.S. Geological Survey (USGS) in cooperation with the Utah Department of Natural Resources, Division of Oil, Gas, and Mining (UDOGM), studied the effects of underground coal mining and the resulting land subsidence on the hydrologic system near the North Fork of the Right Fork (NFRF) of Miller Creek in Carbon and Emery Counties, Utah. This initial study was documented in a USGS report by Slaughter and others (1995). From 2004 to 2005, the USGS, in cooperation with the Bureau of Land Management (BLM), conducted a study that reassessed the hydrologic system 13 years after the completion of longwall mining. This study compared hydrologic conditions in 2004-2005 to those observed prior to longwall mining underneath the NFRF of Miller Creek, and to those reported during 1988-1992. This study provides additional data on the long-term effects of longwall coal mining conducted at shallow-to-moderate depths (50 to 1,000 ft) of overburden on surrounding hydrologic systems. Overburden refers to material overlying a deposit of useful geological materials or bedrock.