ML16295A182
| ML16295A182 | |
| Person / Time | |
|---|---|
| Issue date: | 06/07/1988 |
| From: | Kerr W Advisory Committee on Reactor Safeguards |
| To: | Zech L NRC/Chairman |
| References | |
| D880607 | |
| Download: ML16295A182 (1) | |
Text
D880607 The Honorable Lando W. Zech, Jr.
Chairman U.S. Nuclear Regulatory Commission Washington, D.C. 20555
Dear Chairman Zech:
SUBJECT:
INSERVICE INSPECTION OF BOILING WATER REACTOR PRESSURE VESSELS During the 338th meeting of the Advisory Committee on Reactor Safe-guards, June 2-4, 1988, we met with the NRC Staff to review the status of the inservice inspection program of boiling water reactor (BWR) pressure vessels. This matter was also considered during a meeting of the ACRS Subcommittee on Metal Components on May 26, 1988.
We were told that the NRC Staff is proposing a plan that would require the inspection of all accessible shell welds in BWR pressure vessels.
(Very few of these are now being inspected in the older plants due to lack of appropriate equipment and difficulty of access.) The plan would also recommend a performance demonstration to show that the inspector and equipment are capable of detecting and sizing significant flaws in the reactor pressure vessel welds. Although we believe that catas-trophic failure of a BWR pressure vessel should continue to remain outside the design basis, recent experience demonstrates that flaws can grow from the coolant side of the pressure vessel into the steel pres-sure boundary. The proposed inspection program is desirable to maintain the appropriate defense-in-depth, and we therefore encourage its imple-mentation.
Sincerely, W. Kerr Chairman