2008-05-13_REVISION - M1977493 - Laserfiche WebLink

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2.1.1 Construction of the SE Portal Bulkhead and Rockfall Area Repair A. It is Climax's desire to have the bulkhead construction and rockfall area repair activities performed prior to the Contractor commencing the remaining rehabilitation activities. B. The Contractor will be required to construct the SE Portal Bulkhead and Rockfall Area Repair in conformance with the Scope of Work and Technical Specifications prepared by Phillips Mining Geotechnical & Grouting Inc. Climax personnel will be conducting the final profile stationing and tunnel section measurement survey in early April 2008. These documents will form the basis of the Issued for Construction drawings and basis for payment. C. For the Climax 2010 project, a concrete hatching plant and geotechnical testing field tab will be established at the Plant Site area. Climax is currently working with the batch plant operation and Master Builders to ensure that the technical specifications for the concrete and shotcrete will be met at the on-site plant. Climax is evaluating the concrete delivery logistics and final conveyance methodology will be determined during the Contractor's site visit. D. As a general description, the bulkhead is approximately 27-ft in total length, including a 14-foot concrete plug, a 10-foot upstream piping system and downstream pipe outlet. The bulkhead design incorporates an approximate 16-hole radial grouting pattern with grout holes extending 8-ft into bedrock. E. The removal of flume boards, pressure washing and mucking will be required prior to construction. It is anticipated that the design engineer will be on site during the initial construction activities to confirm the design parameters and provide construction support. 2.1.2.. Pressure Washing and Mucking ' A.. •.The entire length of the tunnel will be required to be pressure washed and mucked from invert to rib, and in areas north of the bulkhead to the roof where required for rock condition inspection. Because .the engineered• slope of the tunnel is from north.to-.south; it is•;anticipated that the majority of the slimes accumulated in the tunnel will flow to the, south.. Climax is currently reviewing the channel configuration and designing for rock check dams to control the majority of slimes from flowing into downstream water retaining facilities. The Contractor- will be responsible for periodic cleaning and maintenance of the flow conditions immediately downstream of the tunnel south portal. B. Amuck disposal area will be provided by Climax at both North and South Portals. The Contractor will be responsible to tram the muck to these areas. Climax will be responsible for the muck once it is deposited at the designated locations. 2.1.3 Removal of Rotten Timber Sets, Flume Boards and Steel Sets A. Climax is requiring the removal of the old, rotten timber sets and flume boards from the entire length of the tunnel so as to reduce the possible obstruction of water flows. It is estimated that there is .approximately 720 ft of timber sets and 3,540 ft of flume board. The majority of the timber and flume boards anticipated to be removed are in the SE portal and original TMT section (South Portal.) B. The removal of steel helper sets installed during the rockfall of 2001 will be required to be removed. It is estimated that there is 1,195 ft of steel helper sets and rotten timber. The majority of the helper sets and rotten timber are anticipated to be removed from the northern section of the tunnel. C. A timber and steel sets disposal area will be provided by Climax at both the North and South Portals. The Contractor will be responsible to tram the material to these areas. 2.1.4 Installation of Pattern and Cable Bolting A. In areas of good ground, the nominal standard ground support will require the installation of 5-foot- long galvanized split-bolt or Dywidag threaded bolts grouted with cement and plates, on a 5 bolt