Protecting People and the EnvironmentUNITED STATES NUCLEAR REGULATORY COMMISSION
UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR REACTOR REGULATION
WASHINGTON, D.C. 20555
May 2, 1989
Information Notice No. 88-82, SUPPLEMENT 1: TORUS SHELLS WITH CORROSION
AND DEGRADED COATINGS IN
BWR CONTAINMENTS
Addressees:
All holders of operating licenses or construction permits for boiling water
reactors (BWRs).
Purpose:
This information notice updates Information Notice No. 88-82, dated October
14, 1988, by providing additional insight into the underwater inspection
method for detecting corrosion and degraded coatings of suppression pool steel
shells in BWR containments. It is expected that recipients will review the
information for applicability to their facilities and consider actions, as
appropriate, to avoid similar problems. However, suggestions contained in
this information notice do not constitute NRC requirements; therefore, no
specific action or written response is required.
Background:
Information Notice No. 88-82 discussed the problem of corrosion and degraded
coatings in BWR suppression pool steel shells. The notice indicated that the
measured corrosion rate of some torus shells exceeds the design corrosion
rate. Because torus shell degradation affects containment integrity, BWR
licensees perform periodic visual inspections of the suppression pool steel
shells. These visual inspections can be performed in several different ways.
Information Notice No. 88-82 stated that the most effective inspection method
was to drain the torus and inspect it under dry conditions.
Discussion:
The NRC has obtained additional information about underwater inspection tech-
niques of BWR suppression pool shells that addressees may wish to consider.
The capabilities of the underwater technique appear to include desludging,
mapping of critical areas, coating adhesion tests, measurement of dry film
thickness, and spot repairs of degraded areas. Potential advantages from the
technique appear to be reduced radiation exposure of personnel and elimination
of the need for draining the suppression pool.
8904260137
. IN 88-82, Supplement 1
May 2, 1989
Page 2 of 2
No specific action or written response is required by this information notice.
If you have any questions about this matter, please contact the technical
contact listed below or the Regional Administrator of the appropriate regional
office.
Charles E. Rossi, Director
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technical Contact: Daniel Prochnow, NRR
(301) 492-1166
Attachment: List of Recently Issued NRC Information Notices
. Attachment IN 88-82,
Supplement 1 May 2,
1989 Page 1 of 1
LIST OF RECENTLY ISSUED
NRC INFORMATION NOTICES
_____________________________________________________________________________
Information Date of
Notice No._____Subject_______________________Issuance_______Issued to________
89-43 Permanent Deformation of 5/1/89 All holders of OLs
Torque Switch Helical or CPs for nuclear
Springs in Limitorque power reactors.
SMA-Type Motor Operators
88-97, Potentially Substandard 4/28/89 All holders of OLs
Supp. 1 Valve Replacement Parts or CPs for nuclear
power reactors.
89-42 Failure of Rosemount 4/21/89 All holders of OLs
Models 1153 and 1154 or CPs for nuclear
Transmitters power reactors.
89-41 Operator Response to 4/20/89 All holders of OLs
Pressurization of Low- or CPs for nuclear
Pressure Interfacing power reactors.
Systems
88-75, Disabling of Diesel 4/17/89 All holders of OLs
Supplement 1 Generator Output Circuit or CPs for nuclear
Breakers by Anti-Pump power reactors.
Circuitry
89-40 Unsatisfactory Operator Test 4/14/89 All holders of OLs
Results and Their Effect on or CPs for nuclear
the Requalification Program power reactors.
89-39 List of Parties Excluded 4/5/89 All holders of OLs
from Federal Procurement or CPs for nuclear
or Non-Procurement Programs power reactors.
89-38 Atmospheric Dump Valve 4/5/89 All holders of OLs
Failures at Palo Verde or CPs for nuclear
Units 1, 2, and 3 power reactors.
89-37 Proposed Amendments to 4/4/89 All U.S. NRC
40 CFR Part 61, Air licensees.
Emission Standards
for Radionuclides
_____________________________________________________________________________
OL = Operating License
CP = Construction Permit
