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International Approaches to Low-Level Waste Management and Disposal. Larry W. Camper CEP, REP, CIPM Director Division of Decommissioning, Uranium Recovery, and Waste Programs Office of Nuclear Material Safety and Safeguards October 30 – 31, 2014 Low-Level Radioactive Waste Forum
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International Approaches to Low-LevelWaste Management and Disposal Larry W. Camper CEP, REP, CIPM Director Division of Decommissioning, Uranium Recovery, and Waste Programs Office of Nuclear Material Safety and Safeguards October 30 – 31, 2014 Low-Level Radioactive Waste Forum Denver, Colorado
Overview of International LLW Management and Disposal Practices • IAEA RWM approach & standards • Waste classification schemes & examples • Exempt waste and low-activity waste • Waste management safety criteria • Joint Convention - Overview • Near-surface disposal & LLW disposal practices • Common issues in international waste management and practices
Examples of Disused Sealed Sources Classes Example Half-life Activity Volume Example Waste Class i<100 d 100 MBq Small Y-90, Au-198 VSLW (brachytherapy) ii <100 d 5 TBq Small Ir-192 VSLW (brachytherapy) iii <15 a <10 MBq Small Co-60, H-3 LLW (tritium targets), Kr-85 iv <15 a <100 TBq Small Co-60 ILW (irradiators) v <30 a <1 MBq Small Cs-137 LLW (brachytherapy, moisture density detectors) vi <30 a <1 PBq Small Cs-137 ILW (irradiators) Sr-90 (thickness gauges, RTGs) vii >30 a <40 MBq Small, but may Pu, Am, Ra (static ILW be large number eliminator) viii >30 a <10 GBq large numbers of Am-241, Ra-226 ILW sources (gauges)
Exempt Waste Class GSG-1Exempt waste (EW) includes both exempt and clearance. EW is a waste which meets the criteria for clearance, exemption or exclusion from regulatory control for radiation protection purposes as described in IAEA GSR Part 3 (BSS) and RS-G-1.7. • EXEMPT Waste: A practice, or a source exempted on the basis of a safety assessment is of the order of 10 μSv or less in a year. • For low probability scenarios, a different criterion could be used for a dose not exceed 1 mSv in a year. • IAEA GSR Part 3 provided under Schedule I limits of activity concentrationand limits of total activity for each radionuclide. • Exemption Criteria also included dose rates for radiation generators (not to exceed 1 μSv/h at a distance of 0.1 m) from any accessible surface; and the maximum energy of the radiation generated is no greater than 5 keV. • For radionuclides of natural origin, exemption of bulk amounts of material is necessarily considered on a case by case basis by using sing a dose criterion of the order of 1 mSv/y.
EPA LARW, 20.2002 Waste & IAEA VLLW • LARW may be correlated with IAEA VLLW. EPA issued on Nov. 18, 2003 an ANPR on Approaches to an Integrated Framework for Management and Disposal of Low-Activity Radioactive Waste (LARW). • US NRC 20.2002 onsite waste disposal authorization can also be compared to IAEA EW or VLLW. • Dose impacts are quite low (e.g.; in the range of 1% of natural background).
Waste Disposal Safety Criteria • SSR-5 • dose or risk to the representative person who might be exposed in the future as a result of possible natural processes affecting the disposal facility does not exceed a dose constraint of 0.3 mSv/y. • Performance period for short-lived waste sevral hundred years and for long-lived waste several thousand years. • For inadvertent human intruder: • Annual dose <1 mSv (no optimization required) • Annual dose 1 - 20 mSv (site is accepted with optimization) • Annual dose > 20 mV (site is rejected) • 10 CFR Part 61: • Annual dose not to exceed an equivalent of 25 millirems to the whole body, 75 millirems to the thyroid, and 25 millirems to any other organ of any member of the public (ICRP2 dosimetry). • Dose to intruder not specified in Part 61 (but implied to be 500 mrem/y)
Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management • JC is an international treaty among Member States in the IAEA • It required ratification by U.S. Senate & President. USA ratified the JC in April 2003 • So far 69 Member States ratified • JC main purpose is to establish/maintain a safety program (infrastructure) for rad waste, SF, and disused sealed sources (DSSs) • JC requires: • preparation of a national report on the status of safety in rad waste, SF and DSSs • Actively participate in the peer review of each others national safety programs on a 3-year basis. • Establish/maintain a safety program (infrastructure) for rad waste, SF and disused sealed sources (DSSs) Forthcoming events The 5th Review Meeting of the Contracting Parties pursuant to Article 30 of the Joint Convention will be held at the IAEA’s Headquarters between 11 and 22 May 2015.
LLW Disposal Practices • Near Surface Disposal Definition • LLW Disposal Option Practices • Near Surface (30 m deep) • Deep below surface disposal • Above surface disposal • Landfill disposal • Borehole disposal • Bunkers (short-term) • Mine cavity
Belgium: The repository at Dessel will provide a solution for disposal of the Belgian category A Waste. Waste Emplaced in Bunkers
Germany Repository for Radioactive Waste at Morsleben: emplacement chamber with stacked drums low-level waste
US Near Surface Generic Design Concept USA Commercial LLW Disposal Facilities
Hot Issues in LLW Disposal • Handling large volume of RW after severe accident • Containment & treatment of liquid waste • How to deal with human intrusion • Exempt & clearance waste • Unified waste classification scheme for the JC manifest • Compliance with safety criteria & site stability • Deep borehole disposal • Site-specific analysis - safety case & Compliance period • DU disposal
Handling of Large Volume of Waste after Sever Accident (Japan’s Fukushima Accident) http://www3.nhk.or.jp/nhkworld/english/news/nuclearwatch/20140911.html Current Status Planned