Laserfiche WebLink
operation as the coal to be mined lies in a thick seam (50 ft) with <br />• no parting or other contamination. Hydraulic mining of any <br />particular part of the sublevels will be stopped when contamination <br />from caving of the hanging wall occurs. <br />Consequently, it is estimated that 1~ of the production during the <br />development of the main entries will be waste material, based on <br />mining experience in other hydraulic mines. During hydraulic <br />mining, the percentage may increase to a maximum of 10 percent of <br />the raw production; this figure includes a very small amount of <br />coal fines (<100 mesh), since the coal cleaning circuit is designed <br />to recover much of what would otherwise be waste coal. <br />Economically, recovery of coal even at the expense of increasing <br />the ast~ content of the product is a viable strategy. <br />idCIG is proposing to dispose of such waste in underground mined-out <br />areas. However, prior to having such an area available, refuse <br />generated during the development of the main entries as well as a <br />• certain number of sublevel entries and during the hydraulic mining <br />of the first two sublevels (Figure 9.3-1) needs to be temporarily <br />stored on the surface. Based upon anticipated production figures, <br />approximately 15,000 tons of refuse must be stored on-site prior to <br />its underground disposal. <br />The project coal processing waste temporary holding pile will be a <br />nominal 670 feet long by 150 feet wide and 9 feet tall. The <br />temporary pile will not constitute an embankment and is designed to <br />be free-draining. This pile will consist of a mix of broken and <br />pulverized rock, and shales. This pile will have a finished side- <br />slope angle of 2:1 (2H to 1V) or less. Epoxy or acrylic polymer <br />emulsion spray will be applied to the pile as necessary to control <br />erosion. Once the refuse disposal system is in operation ti~is <br />temporarily stored material will be reclaimed and disposed of <br />together with the then generated refuse. <br />. NCIG - Coal Ridge #1 4-47 ABC/1145/910509 <br />Tit-7 <br />