United States Nuclear Regulatory Commission - Protecting People and the Environment

Procedural Guidance for Pipe Replacement at BWRS (Generic Letter No. 84-07)

                               UNITED STATES 
                          WASHINGTON, D. C. 20555  

                               March 14, 1984 




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 a  

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description 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 

Procedural Guidance 
Page Last Reviewed/Updated Friday, May 22, 2015