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Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Bipartisan nuclear waste bill introduced in U.S. House
U.S. representatives Mike Levin (D., Calif.) and August Pfluger (R., Texas) have introduced the bipartisan Nuclear Waste Administration Act of 2024, which would establish an independent agency to manage the country’s nuclear waste.
In addition to establishing a new, single-purpose administration to manage the back end of the nuclear fuel cycle, the bill would direct a consent-based siting process for nuclear waste facilities and ensure reliable funding for managing nuclear waste by providing access to the Nuclear Waste Fund. According to Pfluger and Levin, the bill’s provisions are in line with recommendations from the Blue Ribbon Commission on America’s Nuclear Future.
Daniel S. Williams, John C. Rommel, Raymond L. Murray
Nuclear Technology | Volume 87 | Number 4 | December 1989 | Pages 1134-1144
Late Paper | TMI-2: Decontamination and Waste Management / Nuclear Safety | doi.org/10.13182/NT89-A27705
Articles are hosted by Taylor and Francis Online.
Criticality safety and adherence to established keff criteria had to be demonstrated for the various defueling operations performed at Three Mile Island Unit 2. This included determination of adequate neutron poisoning for the reactor coolant system (RCS), design of the defueling canisters, the canister-handling devices, the storage racks, and the shipping cask. Tools, equipment, and support systems required for the defueling operation also had to adhere to criticality safety requirements. The keff criterion used to define the poison concentration for the RCS was ≤0.99. This criterion, coupled with an extremely conservative core model, led to a poison concentration that provided an appropriate margin of safety. To define the fixed poison requirements for the defueling canisters, a keff criterion of <0.95 was used for both single canisters and arrays in all credible configurations. For all design analyses, bounding assumptions were made. For each set of analyses performed, the evaluation of keff included an allowance to account for uncertainties in the calculated values. A criticality benchmark study was completed to determine appropriate computer code bias values for both the RCS and canister analyses. A lenticular model, which included the entire fuel inventory, was used to define the RCS boron concentration. Based on the analysis by Oak Ridge National Laboratory, a boron concentration of 4350 ppm was required to meet the keff criterion. Babcock and Wilcox Company performed the design analyses for the defueling canisters. Each type of canister was explicitly modeled and analyzed using the KENO code. The design requirements mandated that the diameter of the canisters be larger than critically safe dimensions; thus, fixed boron poisoning was utilized. The fixed poison used in the canisters was either Boral plates or stacked sintered boron carbide pellets. The quantity and location of the canister poison was determined based on keff limits and operational criteria for the canisters. Analyses were also performed to ensure that keff was ≤0.95 for canisters contained within the canister-handling devices.
