The Mineral Reserve estimate was prepared by AMC Consultants Pty Ltd (AMC) as part of the feasibility study, and according to the CIM Standards on Mineral Resources and Mineral Reserves Definitions and Guidelines. The reserves were estimated by Qualified Person (under National Instrument 43-101) Mike Thomas MAusIMM(CP) of AMC. The estimate for the New Afton project, announced in April 2007, is presented below:

Using a cut-off value of CDN$15/t of ore

The reserve was estimated based upon a block caving mining method using the block model prepared by Scott Wilson RPA, taking into account the effect of mixing Measured and Indicated Resources with internal and external dilution from low-grade and barren material. They also took into account the mineralized material that will be uneconomic to recover at the metal prices used for the reserve estimation and will remain in the cave at the end of the mine life.

Block caving was selected after consideration of a range of caving and non-caving mining methods. Economic analysis and risk assessment indicated that block caving would provide the best economic return, combined with the highest resource recovery and the lowest technical risk.

Block caving requires the orebody to be undercut, enabling the ore to collapse and fragment (cave) into underlying drawpoints, from where it is extracted. Three cave areas are included. Block 1 (B1) and Block 2 (B2), separated by a low-grade pillar, will have draw points on the same extraction level (approximately 550 meters below surface), whilst Block 3 (B3) will have its extraction level approximately 120 meters deeper.

AMC designed permanent accesses to the underground workings on the north (footwall) side of the deposit because the deposit is bounded on the southern side by the Hanging wall Fault, which is anticipated to be difficult to mine through. An access decline will provide early access to the undercut and extraction levels from the base of the existing exploration decline. The decline will be driven at 5.5m x 5.5m at a gradient of 1:6 (16.7%).

A new conveyor decline will be developed at the same gradient from a portal located close to the proposed mill site. The conveyor decline was designed with four straight legs, varying in length from 700 meters to 1,400 meters with a cross section that will provide adequate clearance for a loaded 50 tonne capacity truck and the conveyor structure, which will be suspended from the roof of the decline. Lateral accesses to the undercut and extraction levels, crusher, workshops and other underground infrastructure are designed to accommodate 50 tonne capacity trucks and high capacity scoops.

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A low height undercut is designed with a flat section over the drawbell and an "A" shape forming the crown of the major apex. A vertical interval of 17 meters floor to floor was adopted between the undercut level and the extraction level below. An offset herringbone layout is planned for the extraction level with a nominal drawpoint spacing of 13 meters. The excavations were sized to suit either diesel or electric scoops with a 6 – 7 tonne capacity. Ground support standards on the extraction level will be high with extensive use of fibre crete, rockbolts and cable bolts. Steel sets will be used to protect draw point brows.

Mining will commence at the western end of B2 and progress to the east into B1. B3 will be mined in conjunction with B1. A program is in place to dewater the open pit and stabilize it up to 50 meters depth of saturated debris that has collected there. The program will be designed after the supernatant water has been removed and the debris can be inspected and sampled. The program will involve building a road with the aid of geotextiles on the debris, drilling dewatering wells and reducing the moisture content of the fine fraction of the debris with the aid of vacuum pumps to mid way between the plastic and the liquid limit.

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