NRC Generic Letter 84-07, Procedural Guidance for Pipe Replacement at BWRs
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WASHINGTON, D. C. 20555
March 14, 1984
TO ALL LICENSEES OF BOILING WATER REACTORS (BWRS)
Gentlemen:
SUBJECT: PROCEDURAL GUIDANCE FOR PIPE REPLACEMENT AT BWRS (Generic Letter 84-07)
This letter provides guidance to licensees planning to replace recirculation system piping (or other reactor coolant system pressure boundary piping)
with material that is less susceptible to intergranular stress corrosion cracking. In particular, guidance is provided regarding NRC reviews and approvals that may be necessary.
10 CFR 50.59 specifies the conditions that would require prior NRC approval of changes in the facility. In your compliance with 10 CFR 50.59, we recognize that the decision on whether your planned replacement program involves an unreviewed safety questions can be difficult, and that an understanding of the NRC position on this issue would be helpful in planning your program. The purpose of this letter is to provide as clear a statement as possible of our views on this issue.
We encourage programs to replace piping so as to minimize the potential for cracking and we will expeditiously review any submittals provided to us so as to not delay this important improvement program. We encourage early submittal of appropriate requests for review for those situations that require prior approval. Prior NRC approval is rot necessary unless the proposed change to the facility involves an unreviewed safety question or a change in Technical Specifications.
In all cases, licensees must perform and document appropriate reviews and analyses in accordance with 10 CFR 50.59 and the facility Technical Specifications. These analyses should be maintained by the licensee, in accordance with Commission regulations and the applicable license, to permit the staff to audit such evaluations, as necessary. In those cases where licensees determine that their program for pipe replacement does not involve an unreviewed safety question, there remains the concern that the NRC may, at a later date, disagree with that determination, thereby potentially delaying the program. To minimize that possibility, we have developed a position regarding the major considerations in a pipe replacement program which licensees can use in determining the necessity or desirability of seeking prior NRC approval. That position is contained in the enclosure to this letter.
Replacement of recirculating system piping may involve individual and collective radiation exposure to plant workers beyond that in other routine maintenance work. 10 CFR Part 20 requires that licensees "make every reasonable effort to maintain radiation exposures, and releases of radioactive materials in effluents to unrestricted areas, as low as is reasonably achievable." We request that adescription of your radiation protection program for the pipe replacement effort be furnished to us as early as possible before initiating the replacement program. Your submittal should include a description of appropriate pre-planning procedures, shielding, equipment, personnel training, estimated total cumulative dose, and other measures to be initiated that will keep exposures as low as reasonably achievable. We anticipate that most pipe replacement programs can be accomplished through suitable controls so as to limit cumulative exposures to less than about 2000 person-rem. We will plan to meet with licensees whose programs involve greater dose estimates.
This request has been approved by OMB Clearance Number 3150-0011, which expires April 30, 1985.
Darrell G. Eisenhut, Director Division of Licensing Office of Nuclear Reactor Regulation
Enclosure:
Procedural Guidance
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