Spent fuel storage facilities

To achieve these objectives, the design of spent fuel storage fiicilities shall incorporate features to maintain fuel subcritical, to remove spent fuel residual heat. 

Various technical and performance requirements are relevant to facility designs for both wet and dry modes of spent fuel storage. These basic design requirements, together with the classification of storage types, are discussed below. 

In the design process, appropriate analytical methods, procedures and tools should be used in conjunction with suitably selected input data and assumptions for both normal operational states and credible deviations. Only verified methods are acceptable for predicting the consequences of operational states and design basis 

As part of the overall process leading to an acceptable design, its evolution and the supporting rationale should be clearly and adequately documented and kept readily available for future reference. The exact content of this documentation, which is likely to be of particular interest to all those involved in the construction, licensing, operation and eventual decommissioning of the facility, may vary somewhat due to facility specific factors. The supporting documentation shall include a full Safety Analysis Report (SAR). 

It should be recognized that in some Members States the general public is involved in the decision making process on the acceptability of proposed interim spent fuel storage facilities. 

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As of March 2003, there were 26 spent fuel storage facilities in the United States located in 21 states. A total of about 160,000 spent fuel units containing about 45,000 short tons (41,000 metric tons) of radioactive waste were stored on-site at nuclear power plants and off-site at special storage areas. More than 97 percent of the wastes were still being held at on-site facilities the rest had been transported to off-site locations. 

Spent Fuel The largest single radioactive waste disposal problem is the spent fuel from military and commercial reactors. As discussed earlier, the spent fuel from commercial reactors is stored in water ponds at the reactor sites. The spent fuel storage facility consists of a cooling and cleanup system for the water along with equipment to safely transfer the fuel rods from the reactor to the storage area. A typical pool will have a volume of 400,000 gal. The water will contain 2000 ppm boron that acts as a neutron absorber and will be maintained at a temperature of <70°C. 

The decay heat is considerable at short cooling times due to the very high decay rate (see Fig. 19. IS). Before unloading spent fuel from a reactor, the used fuel elem ts are first allowed to cool in the reactor by forced circulation. Within a few weeks they are th transferred under water to the cooling basin at the reactor site for an additional cooling time, usually 6—12 months, after which they may be transferred to a central spent fuel storage facility. In the absence of such facilities, sp it fuel elemrats can be stored in the reactor pools for many years. During this time the radiation level and heat production decrease considerably. 

ANSI/ANS-57.2-1983, "Design Requirements for Light Water Reactor Spent Fuel Storage Facilities at Nuclear Power Plants."... 

AR63 Design of spent fuel storage facilities. No. 116, 23 February 1995. 

AR308 1.13 Spent fuel storage facility design basis (for comment) (Draft CE913-5, Proposed revision 2,... 

In December 1994, a meeting of corrosion experts was held at IAEA Headquarters in Vienna as part of an ongoing CRP entitled Irradiation Enhanced Degradation of Materials in Spent Fuel Storage Facilities. During this meeting, spent fuel corrosion issues at SRS and other sites in the USA were discussed by the SRS participant with the IAEA and the European participants. 

Since a limited number of coupon racks were distributed to the partid-pants, the amount of data collected was also limited. Overall, the corrosion observations indicated that the spent fuel storage facilities at OAEP are adequate for mid-term storage. 

Since the acceptance criteria are met for the spent fuel storage facility, this issue is resolved for the System 80+ Standard Design. 

Methods of Criticality Analysis for Spent-Fuel Storage Facilities, C. O. Brown, L. E. Hansen (Exxon Nucl Co)... 

INTERNATIONAL ATOMIC ENERGY AGENCY Design of Spent Fuel Storage Facilities, Safety Series No. 116 (1994)... 

Consistent with proliferation-resistance objectives, there are no fresh or spent fuel storage facilities outside the AFPR vessel at the plant site. 

The operation mode presumes no on-site refuelling and fresh or spent fuel storage facilities on the site. Fuel management for serial BN GT-300 plants would be concentrated at a single (regional) site. The reactor modules for refuelling (de facto, replacement) will be delivered to and moved from the operation site in conventional spent fuel containers. 

The absence of on-site refuelling means that there are no fresh or spent fuel storage facilities on the site and no access to the core during the whole period of reactor operation with this, all accounting and verification procedures are concentrated at special refuelling sites ... 

Excess reactivity in the FUJI MSR is always kept very low, so that any unauthorized extraction of the fuel salt even in small amounts could be easily detected. By virtue of a high conversion ratio, the necessity of addition of fissile material remains small so the plant has no actual fresh or spent fuel storage facilities, which could otherwise be the possible target of diversion or theft ... 

This group of characteristics specifies on-site facilities designed to contain the spent fuel assemblies discharged from the reactor. Basically, there can be two types of spent fuel storage facilities available on site to the unit a spent fuel pool and an interim spent fuel storage facility. The spent fuel pool is usually located in the containment or in the reactor building next to the reactor to facilitate the transport of fuel from the reactor to the pool by a refuelling machine. The spent fuel pool is partially filled with water and the assemblies are left in the... 

The Evaluation of the Pool Components Integrity by the Concentration of the Corrosion Products in the Pool Water. Conference VTT Symposium 63 IAEA Technical Committee Meeting on the Methods Used in Design of Spent Fuel Storage Facilities, Espoo, Finland,... 

ANS 2.19 Guidelines for elevating site related parameters for independent spent fuel storage facilities... 

The Safety Guide is related to two other Safety Series publications on the subject of spent fuel storage Operation of Spent Fuel Storage Facilities [2] and Safety Assessment for Spent Fuel Storage Facilities [3]. 

The purpose of this Safety Guide is to provide details on the design of interim spent fuel storage facilities. Such guidance is required to define and control the extent and quality of the facility, and will assist the designer in preparing technical documentation. 

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