Spent fuel and high-level waste

Spent fuel storage

The United States produces SNF in commercial NPPs and research reac­tors. Currently, 104 licensed nuclear power reactors provide about 20% of US electricity. Information on US nuclear power reactors is provided in the Convention on Nuclear Safety US National Report (IAEA, 2012).

All operating nuclear power reactors are storing SNF in NRC-licensed, onsite SNF pools, and over half are storing SNF in NRC-licensed independ­ent spent fuel storage installations (ISFSIs) located onsite. Given the cir­cumstances regarding reconsideration of the US strategy for underground geologic disposal of SNF and HLW and the work performed by the Blue Ribbon Commission (BRC) on America’s Nuclear Future (see Section 18.6), the current US approach to SNF management will continue. SNF will remain in onsite storage at the NPP where it was generated in spent fuel pools or at ISFSIs until a national long-term strategy is decided.

Most NPPs that have been decommissioned or are undergoing decom­missioning also have SNF stored onsite pending disposal. Most permanently shut-down commercial nuclear power reactors currently have, or are plan­ning to have, their SNF stored at onsite ISFSIs. NRC amended its regula­tions in 1990 to allow licensees to store SNF in NRC-certified dry storage casks at licensed power reactor sites. Dry storage systems were developed as the preferred alternative (versus new pool construction). Most SNF is loaded in canisters with inert gas and welded closed. The canisters are then placed in storage casks or vaults/bunkers. Some cask designs can be used for both storage and transportation.

There are two primary canister-based, dry-cask storage systems for SNF in the United States (NRC, 2012a). One design involves placing canisters vertically or horizontally in a concrete vault used for radiation shielding and protection of the canister. The other design places canisters vertically on a concrete pad and uses both metal and concrete storage overpacks for radiation shielding and canister protection (NRC, 2012b).

Table 18.4 summarizes the types and numbers of US SNF storage facili­ties. Complete lists of these facilities of SNF storage facilities are provided in the annex of the United States Fourth National Report for the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management (the complete document can be found at: http://www. em. doe. gov/pdfs/4th_US%20_Nat%20_Report%20%2009-21 -11.pdf). Fig. 18.2 shows the location of independent SNF storage installa­tions and other SNF storage facilities.

Recently, the NRC has renewed the licenses for several ISFSIs for a 40-year term, extending the total storage duration authorized by NRC for

Table 18.4 Spent fuel storage facilities

Function

Number of facilitiesa

Inventory (as of 2010)b

Units0

Government Wet storage

8

34

MTHM

Dry storaged

7

2,420

MTHM

University research facilities Wet storage

21

1,042

kg U

Dry storage

0

0

kg U

Other research and nuclear fuel cycle facilities Wet storage

3

36

kg U

Dry storage

1

102

kg U

Onsite storage at nuclear power plants0 Wet storage

68

49,067

MTHM

Dry Storage

52

15,357

MTHM

a In some instances, multiple facilities at a given installation are counted as a single facility (e. g., in the case of shared storage pools or independent spent fuel storage installations).

bAdditional inventory tables can be found in the United States Fourth National Report for the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management at http://www. em. doe. gov/pdfs/4th _US%20_Nat%20_Report%20%2009-21-11.pdf. c MTHM = metric tons of heavy metal.

d Includes NRC-licensed facilities at the DOE Idaho Site and Fort St. Vrain in Colorado.

e Includes GE Morris and Utah Private Fuel Storage, which are not located at a nuclear power source.

image206

18.2 Location of US spent fuel and HLW storage installations.

60 years. The NRC determined that the licensees’ aging management plans along with their surveillance activities were sufficient to ensure that the SNF can be safely stored and retrieved at the end of the 60-year storage period (NUREG, 2011).

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