Established in the 1930s, the Northern Transportation Route (NTR) served to transport pitchblende ore 2,200 km from the Port Radium Mine in Canada’s Northwest Territories to Fort McMurray in Alberta. From there, the ore was shipped 3,000 km by rail to the Town of Port Hope, Ontario, where it was refined for its radium content and used for medical purposes. Later, transport and refinement focussed on uranium. The corridor of lakes, rivers, portages and roads that made up the NTR included a number of transfer points, where ore was unloaded and transferred to other barges or trucks. Ore was occasionally spilled during these transfer operations and, in some cases, subsequently distributed over larger areas as properties were re-developed or modified. In addition, relatively small volumes of ore were sometimes transported by air to the south. Since 1991, the Low-Level Radioactive Waste Management Office (LLRWMO), working with communities and its consulting contractors, has conducted surveys to identify and characterize spill sites along the NTR where soils exhibit elevated concentrations of uranium, radium and/or arsenic. In addition to significant areas of impact in Fort McMurray, contamination along the NTR was centred in the Sahtu region near Great Bear Lake and along the southern part of the Slave River. Early radiological investigations found contaminated buildings and soil and occasionally discrete pieces of pitchblende ore at many transfer points and storage areas along the NTR. Where possible, survey work was undertaken in conjunction with property redevelopment activity requiring the relocation of impacted soils (e.g., at Tulita, Fort Smith, Hay River, and Fort McMurray). When feasible to consolidate contaminated material locally, it was placed into Long Term Management Facilities developed to manage and monitor the materials over extended timelines. Radiological activity generated by these engineered facilities are generally below thresholds established by Canadian regulators, meaning they are straightforward to maintain, with minor environmental and community impacts. Securing community acceptance for these facilities is critical, and represents the predominant development component of plans for managing ore-impacted soils. In those circumstances where local consolidation is not achievable, materials have been relocated to disposal facilities outside of the region. The LLRWMO is continuing a program of public consultation, technical evaluation and environmental assessment to develop management plans for the remaining ore-impacted sites on the NTR. This paper will highlight current activities and approaches applied for the responsible management of uranium and radium mining legacies.
МАТЕМАТИЧЕСКИЙ АНАЛИЗ ДИНАМИКИ ЧИСЛЕННОСТИ НЕКОТОРЫХ ОКОЛОВОДНЫХ ВИДОВ ПТИЦ ОСТРОВОВ СИВАША