Laserfiche WebLink
RULE 4 PERFORMANCE STANDARDS <br />4.23.2(4) Prevent Pollution of Surface and Groundwater and to Reduce Fire Hazards <br />Ground water in the pit or highwall mining holes will not be problematic since the South Taylor Pit is <br />essentially dry (minor perched aquifers with limited seasonal flows), and is located above the I" regional <br />aquifer (Trout Creek) by a substantial distance. Ground water flow regimes and the negligible impact that <br />Colowyo's surface mining activities have on ground water as a result of mining these target coal seams/rock <br />interburdens are detailed extensively in Section 2.04.7(1). From this extensive body of data and from <br />experiences to date with mining activities, no toxic forming or acid forming water discharge is anticipated <br />from any of the highwall openings. Should toxic forming or acid forming water discharges be encountered, <br />the opening exhibiting the discharge will be backfilled within 72 hours of completion. <br />Colowyo will backfill each highwall miner entrance hole within 30 days following coal extraction. All <br />highwall miner entrance holes will be further buried by pit backfill during the normal backfill sequence for <br />the pit to remain in compliance with Rules 4.05.1 and 4.05.2. Ground water hydrologic regimes will be re- <br />established in the backfilled pits with no anticipated detrimental effects from the highwall miner holes. <br />4.23.2(5) Holes Need Not Be Plugged <br />All highwall miner entrance holes will be backfilled in accordance with the requirements set forth in 4.14. <br />4.23.2(6) Division Shall Prohibit Auger (Highwall Mining) Mining <br />There is no probable reason to prohibit the highwall mining in light of no anticipated adverse impacts to water <br />quality, fill stability, pit backfilling, increased resource recovery, and highwall mining is designed for zero <br />subsidence to prevent disturbance or damage to powerlines, buildings, or other surface facilities. <br />4.23.2(7) Backfill and Grading Requirements <br />Highwall mining will be conducted in accordance with the backfilling and grading requirements of 4.14. <br />4.24 OPERATIONS IN ALLUVIAL VALLEY FLOORS <br />The field investigation described in Section 2.04.7 and 2.06.8 resulted in no identification of alluvial valley <br />floors in the general area which would be adversely affected by mining operations; therefore, no special <br />performance standards for operations in the alluvial valley floors are applicable to the South Taylor mining <br />area. <br />4.25 OPERATIONS ON PRIME FARMLANDS <br />Since a negative determination of prime farmland was arrived at using the eligibility requirements established <br />for prime farmland under Section 2.04.12, these performance standards do not apply to the present permit <br />application. <br />4.26 MOUNTAINTOP REMOVAL <br />The South Taylor Pit, although removing the entirety of the X and A seams from the top of the unnamed <br />mountain separating the drainages of Taylor, Wilson, and Good Springs Creeks, Colowyo will be mining <br />deeper coal seams. Based on this information, the Division has determined that the South Taylor pit does not <br />meet the criteria for mountaintop removal. <br />South Taylor/Lower Wilson — Rule 4, Page 18 Revision Date: 4/7/17 <br />Revision No.: RN -07 <br />