Proposed Final Regulatory Guide and Standard Review Plan Section Associated with the Alternative Source Term Rule

June 20, 2000

Dr. William D. Travers
Executive Director for Operations
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001

Dear Dr. Travers:

During the 473^RD meeting of the Advisory Committee on Reactor Safeguards, June 7-9, 2000, we reviewed the proposed final Regulatory Guide 1.XXX (DG-1081), "Alternative Radiological Source Terms for Evaluating Design Basis Accidents at Nuclear Power Plants," and Standard Review Plan Section 15.0.1, "Radiological Consequence Analyses Using Alternative Source Terms." During this review, we had the benefit of discussions with representatives of the NRC staff and of the documents referenced. We previously reviewed the draft versions of these documents and the proposed final rule on the use of alternative source term and provided a report to the Commission dated September 17, 1999.

We find that the proposed final Regulatory Guide and Standard Review Plan Section appropriately address the issues associated with the voluntary use of alternative source terms. We believe these documents are acceptable for issuance. There is, however, a need for both minor editorial changes and to purge the Regulatory Guide of several carryover items from previous regulatory guides that are not appropriate for implementation of alternative source terms. Examples include, specification of the breathing rate to three significant figures for calculation of control room dose consequences and the lack of adequate technical justification for the speciation of iodine in the fuel pin gap. These suggested changes have been provided to the staff for its consideration.

References:

1. Memorandum dated May 5, 2000 from G. M. Holahan, Office of Nuclear Reactor Regulation, NRC, to John T. Larkins, ACRS, Subject: Transmittal of Final Regulatory Guide 1. XXX (DG-1081), "Alternative Radiological Source Terms for Evaluating Design-Basis Accidents at Nuclear Power Plants," and Standard Review Plan Section 15.0.1, "Radiological Consequence Analyses Using Alternative Source Terms."
2. ACRS Report dated September 17, 1999, from Dana A. Powers, Chairman, ACRS, to Greta Joy Dicus, Chairman, NRC, Subject: Proposed Final Rule on Use of Alternative Source Term at Operating Reactors, Draft Regulatory Guide, and Standard Review Plan.