Abandoned Shaft and Raises

General Overview

In December 1999, Kinross Gold Corporation acquired all of the Timmins Gold Camp properties that were held by Royal Oak Mines prior to their filing for bankruptcy. These properties were generally in a state of abandonment at the time of acquisition and progressive rehabilitation work was required as part of an agreement with the Ontario Ministry of Northern Development and Mines.

As part of the Royal Oak property take over, Kinross acquired former mines and associated underground workings in Timmins and nearby Schumacher. These included the Hollinger Mine, the McIntyre Mine, the Coniaurum Mine and the Vipond Mine. These mines had operated at various times between 1912 and 1988. In excess of a hundred vertical and inclined shafts and raises had been driven into the bedrock throughout the area in order to provide suitable access and sufficient ventilation into the underground workings. While their former owners capped a small number of these shafts and raises, the remainder were generally only filled and/or buried and abandoned. Several mine openings were located on private properties in the vicinity of the former Hollinger Mine, outside of the mine perimeter fencing.

The mine openings represent a serious public safety concern and Kinross Gold Corporation, through a unique joint venture agreement with the Ontario Ministry of Northern Development and Mines, has initiated a program to investigate all of these historic shafts and raises and ensure their security. Highest priority was given to those mine openings that were located on private and public lands outside of fenced property boundaries.

Approximately thirty investigations, cap repairs and constructions were carried out in 2000-2001 along the Algonquin Boulevard East (Hwy 101) corridor as well as on the Hollinger Golf Course property, east of downtown Timmins.

The excavation of old caps frequently revealed inadequate raise and shaft cap construction as well as wide-open stopes. Some were protected only by backfill that had bridged over the openings. All old concrete, steel and timber caps were collapsed and loose rock was removed from the walls of the openings. Detailed geotechnical reviews were conducted to characterize the condition of the rock on which the caps would be constructed. The mine openings were backfilled with imported sand prior to placement of concrete form work. Concrete caps were then constructed over the openings in accordance with current mine rehabilitation regulations set out in the Ontario Mining Act. Once the new concrete had been proven to reach the design strength of the caps, the caps were backfilled with appropriate granular soils. The surface was then graded to provide improved drainage. Provisions are made to monitor fill levels in the stopes and to replace fill should it subside. In this manner, the integrity of the stope walls can be maintained.

Implementation of the agreement between Kinross Gold Corporation and the Ontario Ministry of Northern Development and Mines has proven to be a very productive example of industry-government cooperation, and a model for future relationships.