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essed, the cuttings were dropper d laced in mined-out areas underground. ressure on the cutter head. As boring progr em ward p transported, an P which involved slurrying th maintain continuous up was included, s slurred to the cuttings to mined-out aeeas round development waste down the shaft bore and are recover ' ~dergr underg alternative to transP°rhng lion, an ound line would b~Ystalled and the cu any system a»d sump. For this op q_ or 10-Righ convey 21,000 CY into the EMD pumped behind the seals in 7-+ N,as approximately the EMD ound were transpo eepVe ~ec ttings volumeexisnng cuttings not Placed undergr stored south and east Z Ih~r~ t~ 1 Plt• ~ e were loaded into trucks and hauled (16,862 CY swelled by p where th Y This overburden storage s discharged from the existing rock belt, e area (see Map 24 for locations). -fie overburdeu Any excess cutting sediment control system• mixed ori~ coal to the previously approved overburden stwlthin TCC s existing ea 1 Pit• These cutting .tyre cuttings area is in a previously disturbed t1e slope to the south of the ~ washed to recover the co~coal processed ically uality storage area is located ° the mine and therefore were typ volume of low 9 the plant. 'the during conveyance from 10 ercent of the monthly ~ underground ~ P~ °f and coal comprised an estimated 5- P ~ of the refuse stream coming from ya„t• The cuttings then became p s/coal were discharg laced in the refuse pile. Given the fact that the nes through the wash-p the washing process of the cutting osed of undergound in the fines generated during oin to the rocessed through the plant and the fines disp eotechnical analysis of the material g g, the thicken' undcoal were pcouzse fraction was a eotechnical analysis, but from the cutting it was not necessary to conduct a gifting to conducting S thickener underfloor, i1e. refuse pile. "the fine frl ced i the refuse p n for co but found it not to be very ty1ey no long' will be p contain s from the ventilation shaft boring rayless that some of the cutting ally hauled the remainder of the boringssis of the cuttings was TCC test-washed on this, TCC g p. eotechnical analy yt demonstrates that efficient. Based to the refuse pile for disposal. g of the resulting report is presented in Exhibit 25a-2. significant amounts of coal, ile without adversely impacting stability. performed by NWCC and a copy the cutter-head, drive unit, and the cuttings can be placed in the refuse p ~gnsistrng ved from the site. A permanent shaft casing Once the cutter-head broke-through to the surface within the shaft 6Oee the liner and the shaft bore was laced, and the annulus betty temporary headframe were dis yet mores pan rem beams and liner-p e Overburden. of steel ring- the Wadg Ttris ~rnented in segments. ile Sandstone from a e into the shaft. es to isolate the Twentyrnouted to prevent seep g and not seep The cement shaft liner se,i Sandstone was Pressure-gr the water in this unit will be con n were erected ou Additionally, the Twentym and casing operations and removal complyion of shaft boring provides further assurance that, after final c osure, and electrical control building the fan enclosure (fan shroud) and electrical control, monitoring, down on the inside of the shaft. Following fan drive motor, ad surface azea is of equipment from the site, ads, and the fan, of 800,000 cfin the previously constructed concrete p Average pad thickness is 2 feet and tot p Following stems were installed. ventilation fan has a installation. and communication sY ,the installed axial-vane exhausting and surface areas graded and dressed. approximately 3100sf. fence was constructed to enclose the fan with a 3,000 hp drive motor. A wer drops and commissioning, the shaft pad site and access road were cleane -uP eter of 4 and 8 to two additional holes were cased to allow roduction mine water In addition to the main vent shaft, up e two holes were cased to an internal nominal diame of production other ancillary uses into the mine. Th a ressure reliefJareventlany surface discharg were designed top ressure relief valves Teventdany inches. One of the~sure relief and back up p and back-up p system. System Pr a catastrophic failure of both pnmar}' however, installed at that time to seal the casing au P mine water, A manual ball valve was be installed to assure Ihat n° discharge a discharge in mid-2005• ressure relief controls can be removed or replaced with afail-safe valve that would allow for ee future dischazge• If suitable system p 0&/l4lOE will occur, the manual valve may 2.05-45.2 TRO6-56