Canadian regulatory and technical requirements for uranium mine decommissioning Elliot Lake, Ontario experience

Uranium mining in Canada is regulated by the Atomic Energy Control Board (AECB), a federal nuclear control agency whose mission is to ensure that the use of nuclear energy in Canada does not pose undue risk to health, safety, security and the environment. The mining of uranium is regulated by the Atomic Energy Control Act and specifically the Uranium and Thorium Mining Regulations. While the AECB remains the lead regulatory agency, other relevant federal and provincial regulatory bodies are also involved. The regulatory process involves the issuing of licences for specific activities during the life cycle of a mine from siting, construction, operation to decommissioning. The AECB objectives with respect to decommissioning nuclear facilities and uranium mines are to minimize any burden placed on future generations, protect the environment and human health taking into account social and economic factors. This is achieved through a non prescriptive approach where each decommissioning plan is evaluated on a case-by-case basis. This paper illustrates the technical and regulatory requirements that have been applied by the AECB through a number of site specific examples from the recent decommissioning activities undertaken in the Elliot Lake Area situated in Northern Ontario. These decommissioning projects follow a staged approach which includes initial, transitional and closure phases. The most challenging aspect is the long-term management of the acid generating tailings. The regulatory and technical requirements related to the long-term environmental performance, structural integrity and maintenance of the tailings management facilities will be described in detail. (author)