The technical report on ATWS for water-cooled reactors (WASH-1270)[1] discussed the probability of an ATWS event as well as an appropriate safety objective for the event. After several years of discussions with vendors and evaluations of vendor models and analyses, the staff published a status report on each vendor analysis in 1975. This report included detailed guidelines on analysis models and ATWS safety objectives. This item was
originally identified in NUREG-0371[2] and was later declared a USI in NUREG-0510.[3]
The staff's technical findings were published in Volume 4 of NUREG-0460 [4] and the USI was RESOLVED with the publication of a final rule. [5],[6]
[1] WASH-1270, "Anticipated Transients without Scram for Water-Cooled Reactors," U.S. Atomic Energy Commission, September 1973.
[2] NUREG-0371, "Task Action Plans for Generic Activities (Category A)," U.S. Nuclear Regulatory Commission, November 1978.
[3] NUREG-0510, "Identification of Unresolved Safety Issues Relating to Nuclear Power Plants," U.S. Nuclear Regulatory Commission, January 1979.
[4] NUREG-0460, "Anticipated Transients without Scram for Light Water Reactors," U.S. Nuclear Regulatory Commission, (Vol. 1) April 1978, (Vol. 2) April 1978, (Vol. 3) December 1978, (Vol. 4) March 1980.
[5] Memorandum for W. Dircks et al. from S. Chilk, "Staff RequirementsAffirmation/Discussion and Vote, 11:30 a.m., Friday, June 1, 1984, Commissioners' Conference Room, D.C. Office (Open to Public Attendance)," June 1, 1984.
[6] Federal Register Notice 49 FR 26036, "10 CFR Part 50, Reduction of Risk from Anticipated Transients Without Scram (ATWS) Events for Light-Water-Cooled Nuclear Power Plants," June 26, 1984.
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