Laserfiche WebLink
-� However, in so%e %nst_anres ctngre suitable quality coal 1s gear the surface, the <br />overburden raay be reraovgd vitlz a combihatton of dozers ziad scrap('rs, 'rhe over- <br />burdyct wquLI, ct�en be hayLed to, a styckpileat plat -ed 4n mined -out areas for evocn- <br />tu91 tegrad%ng and rstobsoiling. <br />The pr'inc:jpje mining methoq u3ed at Trapper is d4+-1i.ae mirlink, tii._e., raining in <br />sttiPs parallel rq rYte gown hill dib of the goal aears, Each Pit is adjacent and <br />patall,el to Chs previ,au% one. Pit 'widths vary according, to the specific site. <br />Tybic§lly, leach cltt is initiated near the coal outcrop snd woakeq down thg hill <br />until th@ dipping coal becomes Coo deep to re;over @cogomically. on occasion, <br />th6 alit may be worked lip @he hill. When mare tl)§n one seam is recov6red, the <br />patting is temyved in owie of sevsraj methods, 'whin partings up to ten feet thick <br />are r'mobed with a loz�-r, backhoe or siniilyr e9ulPrenG. 'Thickfir par{iqs ire <br />removed Witli a drggline. Fartj nk mriy be ktri,ppPd up -dip or down -dip depending on <br />the p§rticular situation. Strike -line: mining may be Performed in3tead c,f the <br />present dip --line mining metbod it g@olagic conditlPns allow. <br />Thp tbp of the uncovered co41 is cleaned with ?-quipment such as a fronr-end <br />loedet•, nworor graders of rybber I_irad dozer. Ve Goal i% then either, ripped with <br />a dozer 4r <lri:Lled with a (wirt-m§sted coal drill arld theft blasted. F1ole spacings <br />vaYy d.eprtndLng on coal thickn@ss, <br />TWe h<)1e3 are loathed with Ali-F� or other blhsting agents and stehamed with drill <br />cuttings, 'The blasr circuit is then completed end the blast is initiated {refer <br />to Secti6n ).4). <br />Large 6at,khUes or frust enfl loaders ace Vsed to load thN coal into haul trucks. <br />The cpal haulers transport the coal frym the pit to the power plant's grizzly or <br />a coal_ stockpile, The coal haulers exit the pit via an inclihed ramp and enter <br />onto the haUl road system that Coongcts egch pit to the power Plant's grizzly and <br />the cUal stpckpil@s. At a lacer date, a conveyor system may replace part of this <br />truck haul. <br />3-14 <br />Ftc.VISED FEB 13 `81 <br />