Challenge. Develop safety basis for licensing and demonstration of long-term performance of repository

Solution. ARAO, the Slovenian government agency responsible for radioactive waste management, is developing a near surface repository for LLW and ILW located near the Krško Nuclear Power Plant. INTERA is part of a multinational U.S./Swedish/Slovenian/ Austrian consortium of companies contracted to provide the safety basis for licensing the repository. The scope of the project covers the post-closure safety assessment (PCSA), the operational safety assessment, and the development of waste acceptance criteria (WAC) for the repository. INTERA is the lead organization for the PCSA, responsible for coordinating consortium activities to produce the safety assessment and inputs for an environmental impact analysis. Our scope of work includes: developing the regulatory assessment context; evaluating relevant alternative scenarios; evaluating site data and abstracting the data into an appropriate modeling framework; analyzing the regional and local groundwater hydrology and long-term performance of engineered barriers; and performing a radiological assessment of the potential post-closure doses to the biosphere. The operational safety assessment takes account of normal operational and accidental situations, and addresses risks to workers and the public. The assessments are designed to demonstrate compliance with Slovenian regulatory limits and constraints, and to minimize the doses to the biosphere, to the extent possible, at each stage of the disposal program. The post-closure and operational safety assessments form a major part of the basis for establishing the WAC, to ensure that the as-received waste meets acceptable limits and conditions, allowing it to meet safety and operational constraints.