Entergy Operations, Inc., Arkansas Nuclear One Power Plant; Issuance of Environmental Assessment and Finding of No Significant Impact Regarding the Proposed Exemption From Certain Requirements of 10 CFR Part 72

The U.S. Nuclear Regulatory Commission (NRC or Commission) is considering issuance of an exemption, pursuant to 10 CFR 72.7, from the provisions of 10 CFR 72.212(a)(2) and 72.214 to Entergy Operations, Inc. (Entergy). The exemption would allow Entergy to store burnable poison rod assemblies (BPRAs) in Ventilated Storage Cask-24 (VSC-24) systems at the Arkansas Nuclear One (ANO) Independent Spent Fuel Storage Installation (ISFSI).

Environmental Assessment (EA)

Identification of Proposed Action

By letter dated February 3, 2000, Entergy requested an extension to a previous exemption granted to Entergy by NRC on April 9, 1999, from the requirements of 10 CFR 72.12(a)(2) and 72.214 to store BPRAs in VSC-24s at the ANO ISFSI. NRC published an Environmental Assessment and Finding Of No Significant Impact for the previous exemption request in the Federal Register (64 FR 13611, March 19, 1999). The April 9, 1999, NRC letter placed conditions on the exemption, including that no more than four VSC-24s containing BPRAs could be loaded and the loading of these four VSC-24s would need to be accomplished prior to September 1999. These conditions were based on (1) ANO's request to load four casks prior to the September refuel outage to regain full core offload reserves in the Unit 1 spent fuel pool and (2) NRC's expectation of completion of a rulemaking, under 10 CFR 72.214 before the next ANO refueling outage, which would amend the Certificate of Compliance (CoC) for the VSC-24 cask to permit storage of spent fuel containing BPRAs (64 FR 51187, September 22, 1999).

The 10 CFR 72.124 rulemaking is not completed and the ANO, Unit 1, spent fuel pool has again lost full core offload reserves. ANO must load three VSC-24s with fuel containing BPRAs to regain full core offload reserves prior to the next refueling outage, scheduled for Spring 2000.

ANO is a general licensee, authorized by NRC to use spent fuel storage casks approved under 10 CFR Part 72, Subpart K. ANO is using the VSC-24 design approved by NRC under CoC No. 1007 to store spent fuel at the ISFSI. However, CoC No. 1007 does not authorize the storage of BPRAs.

The ISFSI is located 6 miles west-northwest of Russellville, Arkansas, on the ANO Power Plant site. The ANO ISFSI is an existing facility constructed for interim dry storage of spent ANO nuclear fuel.

By exempting ANO from 10 CFR 72.212(a)(2) and 72.214, ANO will be authorized to use its general license to store spent fuel with BPRAs in casks approved under part 72, as exempted, until the 10 CFR 72.214 rulemaking is complete. The proposed action before the Commission is whether to grant this exemption under 10 CFR 72.7.

On December 30, 1998, the cask designer, Sierra Nuclear Corporation (SNC), submitted a Certificate of Compliance amendment request to NRC to address the storage of Babcock and Wilcox (B&W) 15x15 fuel with BPRAs. The NRC staff has reviewed the application and determined that storing B&W 15x15 fuel with BPRAs in the VSC-24 would have minimal impact on the design basis and would not be inimical to public health and safety.

Need for the Proposed Action

ANO has lost full core offload reserves in the Unit 1 spent fuel pool and Unit 1 is scheduled for a refueling outage in Spring 2000. ANO must load three VSC-24s with fuel containing BPRAs to regain full core offload reserves.

Environmental Impacts of the Proposed Action

The potential environmental impact of using the VSC-24 system was initially presented in the EA for the Final Rule to add the VSC-24 to the list of approved spent fuel storage casks in 10 CFR 72.214 (58 FR 17948 (1993)). Furthermore, each general licensee must assess the environmental impacts of the specific ISFSI in accordance with the requirements of 10 CFR 72.212(b)(2)(iii). This section requires the general licensee to perform written evaluations to demonstrate compliance with the environmental requirements of 10 CFR 72.104, “Criteria for radioactive materials in effluents and direct radiation from an ISFSI or MRS [Monitored Retrievable Storage Installation].”

VSC-24s are designed to mitigate the effects of design basis accidents that could occur during storage. Design basis accidents account for human-induced events and the most severe natural phenomena reported for the site and surrounding area. Postulated accidents analyzed for an ISFSI include tornado winds and tornado generated missiles, design basis earthquake, design basis flood, accidental cask drop, lightening effects, fire, explosions, and other incidents.

Special cask design features include a double-closure welded steel multi-assembly sealed basket (MSB) made from SA-516 Gr 70 pressure vessel steel to contain the spent fuel. This MSB is up to 181-inches long, 62.5 inches in diameter, with 1.0-inch thick walls. The MSB is placed inside of a ventilated Concrete Cask (VCC) and positioned for storage on the concrete ISFSI pad. The VCC is up to 213-inches long, 132 inches in diameter, and 31.75-inches thick. The VCC wall consists of a 1.75-inch thick steel inner liner surrounded by reinforced concrete and steel ducts for a passive ventilation system.

Considering the specific design requirements for each accident condition, the design of the cask would prevent loss of containment, shielding, and criticality control. Without the loss of either containment, shielding, or criticality control, the risk to public health and safety is not compromised.

Storage of B&W 15x15 fuel containing BPRAs would increase the maximum potential cask does rates by no or than 13 percent at any location on a loaded VSC-24 system. For a VSC-24 loaded with fuel containing BPRAs, the highest dose would be found at the top center of the cask. This dose was calculated to increase from 30 mrem/hr without BPRAs to 32.2 mrem/hr with BPRAs. The occupational exposure is not significantly increased and off-site dose rates remain well within the 10 CFR Part 20 limits. Therefore, the proposed action now under consideration would not change the potential environmental effects assessed in the initial rulemaking (58 FR 17948).

Therefore, the staff has determined that there is no reduction in the safety margin nor significant environmental impacts as a result of storing B&W 15×15 fuel with BPRAs in the VSC-24 system.

Alternative to the Proposed Action

The staff evaluated other alternatives involving removal of the BPRAs from the fuel assemblies and found that these alternatives produced a greater occupational exposure and an increased environmental impact as a result of handling the BPRAs separately as low-level waste. The alternative to the proposed action would be to deny approval of the exemption and, therefore, require ANO to disassemble and store the BPRAs as low-level waste in separate containers.

Agencies and Persons Consulted

On February 11, 2000, Bernard Bevill from the Division of Radiation Control and Emergency Management, Arkansas Department of Health, was contacted about the EA for the proposed action and had no concerns.

Finding of No Significant Impact

The environmental impacts of the proposed action have been reviewed in accordance with the requirements set forth in 10 CFR part 51. Based upon the foregoing EA, the Commission finds that the proposed action of granting an exemption from 10 CFR 72.212(a)(2) and 72.214 so that ANO may store B&W 15x15 fuel containing BPRAs in VSC-24s will not significantly impact the quality of the human environment. Accordingly, the Commission has determined not to prepare an environmental impact statement for the proposed exemption.

For further details with respect to this exemption request, see the Entergy exemption request dated February 3, 2000, which is docketed under 10 CFR part 72, Docket No. 72-13. The exemption request is available for public inspection at the Commission's Public Document Room, 2120 L Street, NW, Washington, DC, 20555 and accessible electronically through the “ADAMS” Public Electronic Reading Room link at the NRC Web site   (http://www.nrc.gov/nrc/reference.html).