Panel Report

12.1 The McArthur River Site

The decommissioning and reclamation of uranium mines and their associated facilities is intended to return disturbed areas to as near to predevelopment condition as possible. For the McArthur River Project, decommissioning as proposed in the EIS includes the dismantling of surface buildings and their associated infrastructure; the sealing of development shafts and ventilation raises; the appropriate disposal of wastes; the salvage and decontamination of reusable materials; the disposal of non-salvageable material underground; the filling of the water treatment ponds; the contouring of waste rock piles; and the revegetation of disturbed areas.

The mining regulations administered by both federal and provincial governments require submission of a sitespecific conceptual decommissioning plan which includes proposed reclamation activities and associated costs. The plan must be reviewed and approved before operating licences are issued. Mining companies are encouraged to conduct decommissioning and reclamation activities as soon as possible after an area is removed from production. This allows for the updating of the conceptual decommissioning plan and the adjustment of the amount of financial surety required.

At the end of mining, the operator is required to submit, for review and approval, a detailed final decommissioning plan based on existing conditions and the best available technology. Once decommissioning and reclamation work have been completed, the mining company is required to monitor the site for a number of years. The length of the monitoring period is determined by the stability of the site and the levels, if any, of contaminants being discharged into the receiving environment. Only after on-site monitoring has demonstrated that decommissioning has been successful is a release granted from further requirements.

It should be possible for Cameco to leave a minimal footprint when the McArthur River site is decommissioned. The ore would be milled at Key Lake, the tailings would be deposited in the DTMF, and the mineralized waste would be placed in mined-out drifts underground at McArthur River, or in the DTMF. Only a stockpile of clean waste would be left on the site. With careful management of waste rock during operations, no significant environmental concern should remain at the site after decommissioning and reclamation. All activities during operation should be planned and implemented to reduce or eliminate the size and duration of the mine’s footprint at the McArthur River site.

During public hearings, the desire of local communities to be consulted on conceptual and final decommissioning plans was clearly heard. Because of the proximity of the mine site to the northern communities, the panel believes that northern involvement should extend beyond information consultation, to participation in the decommissioning, reclamation and postdecommissioning monitoring activities. The continuing involvement of the Environmental Quality Committees is an ideal vehicle through which northern community residents could be consulted on decommissioning issues, activities and monitoring.

The communities do want to be involved in the monitoring. And we see that as an important step and are working towards the communities being in valved. And they have already started being involved in hands-on sampling in some of the government programs.

Pam Schwann, Transcript of McArthur River Public Hearings, Regina, Saskatchewan, September 4, 1996, p. 128.

12.2 The Deilmann Tailings Management Facility

The decommissioning of the Deilmann Tailings Management Facility (DTMF) would be the most significant long-term challenge faced by the proponent and the regulatory agencies. The proponent plans to decommission the DTMF by capping the tailings mass with inert, screened, outwash sand or till. The capping would be applied subaqueously, with the objectives of enhancing consolidation of the tailings mass and providing a diffusion barrier against long-term contaminant release. Once the capping is completed and contaminant levels in the pond above the tailings have been demonstrated to be acceptably low, water levels would be allowed to rebound, re-establishing the lake that was dewatered for the original Key Lake mine.

Research is being done by Mine Environment Neutralization Drainage (MEND) into the subaqueous placement of organic layers on mine wastes in order to reduce the flux of contaminants into the overlying water column. The applicability of this and other research to the Deilmann Tailings Management Facility decommissioning should be fully evaluated, and the conceptual decommissioning plan adjusted to take advantage of any useful results.

The EIS states that the underdrain/side drain system at the DTMF, together with the dewatering system (vertical wells, horizontal drains, drainage trenches), would have sufficient filter drainage and pumping capacity to remove all groundwater and surface water from the pit walls and the tailings mass. During operations, pumping would capture any contaminated water from the tailings area and send it for treatment. It is recommended that decommissioning allow for recommissioning of this dewatering system at a later date, should the levels of contaminants exiting the pit area exceed those predicted by modelling. This would re-establish the ability to intercept and treat contaminated water before it can adversely impact the receiving environment. Reestablishment of the pump-and-treat system would allow time to develop mitigation measures for any unacceptable contaminant levels exiting the decommissioned Deilmann Tailings Management Facility. As stated in Section 10.3, a plan should be implemented for monitoring this and other tailings management facilities indefinitely.

After the mines are closed and shut down in the future, we the Dene people of Fond du Lac will still be here. In fact, all the communities will still be here.

Caroline Isadore, Chief of the Fond du Lac Band, Transcript of McArthur River Public Hearings, La Ronge, Saskatchewan, October 1, 1996, p. 32.

12.3 Roads

The proponents should be prepared to decommission roads built to support a project once they are no longer needed. However, the public has indicated a wish to be consulted before decisions are reached on decommissioning of the Fox Lake winter road. Decommissioning should be the subject of full discussions with all stakeholders, including the people from Pinehouse, Patuanak and the English River First Nations. The wishes of the traditional users of the land in the area should be respected. In particular, the bridges currently in place should be maintained until the northern communities have had an opportunity to assess potential benefits and liabilities associated with their removal.

12.4 Financial Guarantees

Both the federal and provincial governments have introduced legislation and/or regulations requiring mining companies to provide, prior to mine start-up, financial guarantees of sufficient magnitude to cover the costs of all decommissioning activities. This financial guarantee is intended to ensure that uranium mine and mill sites can be decommissioned at no cost to Canadian or Saskatchewan taxpayers even if a mining company were unable to meet its commitments. The amount of the financial guarantee required by government is based on the needs outlined in the conceptual decommissioning plan, which is subject to regular reviews to ensure that it reflects existing conditions.

12.5 Uranium Mining Contingency Fund

The financial guarantees for decommissioning costs cover a period of, at most, a few decades after mining ceases. When contaminant concentrations have been reduced to acceptable levels, and the leakage of contaminants from tailings management areas and waste rock piles, etc., has stabilized, the operator can apply to abandon the sites.

The companies seem to believe that they will be able to walk away from these projects. I think that we will need to continue to monitor these sites long after the companies have taken their profits and run.

Karen Weingeist, Transcript of McArthur River Public Hearings, Saskatoon, Saskatchewan, September 15, 1996, p. 160.

However, tailings areas have the potential to pose a threat to the receiving environment for periods which may far exceed the life of an individual mining company. Consequently, the tailings management facilities will require monitoring for the foreseeable future. The panel agrees with the discussion and conclusions contained in the report submitted by the environmental assessment review panel that studied uranium mine tailings management areas near Elliot Lake, Ontario.⁸⁰ As with the Elliot Lake areas, the decommissioned Deilmann Tailings Management Facility would be required to contain contaminants for millennia, during which time many aspects of both the biophysical and institutional environments would be altered. There must be some means of ensuring regular monitoring of the integrity of contaminant containment systems and the performance of mitigative measures after institutional responsibility for the area has been transferred back to the government. For this reason, the panel recommends the establishment of a contingency fund to provide for the ongoing costs of long-term monitoring (and mitigation, should it be required) after the responsibility for the sites is returned to government.

The value of the contingency fund should be sufficiently large to cover the costs of long-term monitoring and maintenance of the Deilmann Tailings Management Facility and the potential implementation of contingencies. Instead of establishing such a fund for each mine independently, there might be merit in considering an industry-wide Uranium Mining Contingency Fund. Such a fund could provide better overall fiscal protection to future generations and cost the mining companies less in total. There could also be a single authority to manage the fund and oversee the maintenance, monitoring and mitigation activities at all decommissioned uranium mine and mill sites.

In 1980, the Government of Saskatchewan established a similar fund, referred to as the Environmental Protection Division of the Saskatchewan Heritage Fund.⁸¹ It was created, in part, to provide a contingency fund for monitoring abandoned uranium mine and mill sites and for dealing with unforeseen environmental problems from these sites. Although the Saskatchewan Heritage Fund has been repealed, the Environmental Protection Division continues as a reserve, reported at $11.9 million,⁸² within the consolidated fund. The panel recommends that the total remaining in this Environmental Protection Division be used as seed money for the Uranium Mining Contingency Fund. Currently, revenue from investment income does not accrue to the fund; however, this should be changed, with interest being reinvested in the fund to maintain its value and to enhance its viability.

12.6 Conclusions and Recommendations

Decommissioning, since it will take place in the future, is only described conceptually at this stage; the scrutiny and acceptance of specific details must be entrusted to the regulatory agencies. These agencies should ensure that they receive advice from local residents at each stage, and for all elements, of the decommissioning process. Because of the proximity of the mine site to northern communities, this involvement should extend beyond consultation, to participation in the decommissioning, reclamation and postdecommissioning monitoring activities. The Environmental Quality Committees are appropriate vehicles through which northern community residents could be consulted on decommissioning issues, activities and monitoring.

This project, and in particular the Deilmann Tailings Management Facility, would require long-term monitoring and possible mitigative activities in the future. Arrangements should be made to guarantee that monitoring and any required mitigation could occur without placing a financial burden on future generations. For this reason, the panel recommends the establishment of a contingency fund to provide for the ongoing costs of long-term monitoring and mitigation, after the responsibility for the sites is returned to government.

⁸⁰ D. Kirkwood, D. McCreath, and T. Peters, Decommissioning of Uranium Mine Tailings Management Areas in the Elliot lake Area, June, 1996, Supply and Services Canada, Section 3.4, The In-Perpetuity Problem, pp. 16-17.

⁸¹ Saskatchewan Environment and Resource Management, Final Report. Information from the Government of Saskatchewan requested by the Federal Provincial Panel on Uranium Mining in Northern Saskatchewan for the Cigar Lake and McArthur River Projects, May, 1996, Section 1, p. 46.

⁸² Ibid.