ML19344E922
| ML19344E922 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 08/22/1980 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Daltroff S PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| References | |
| NUDOCS 8009120103 | |
| Download: ML19344E922 (1) | |
Text
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- pe uruq4 UNITED STATES 8
NUCLEAR REGULATORY COMMISSION
,E REGION I e
M1 PARK AVENUE g * * * * *,o,g 9
KING OF PRUSSIA, PENNSYLVANIA 19406 August 22, 1980 D:cket Nos. 50-277 50-278 Philadelphia Electric Company ATTN:
Mr. S. L. Daltroff Vice President Electric Production 2301 Market Street Philadelphia, Pennsylvania 19101 Gentlemen:
The enclosed Supplement No. 3 to IE Bulletin No. 80-17, " Failure of 76 of 185 Control Rods to Fully Insert During a Scram at a BWR," is forwarded to you for action.
A written response is required.
In order to assist the NRC in evaluating the value/ impact of each Bulletin on licensees, it would be helpful if you wculd provide an estimate of the manpower l
expended in conduct of the review and preparation of the report (s) required by the Bulletin. Please estimate separately the manpower associated with corrective actions necessary following identification of problems through the Bulletin.
If you desire additional information regarding this matter, please contact this office.
Sincerely, e
Grier Director l
Enclosures:
l 1.
Supplement No. 3 to IE Bulletin No. 80-17 l
2.
List of Recently Issued IE Bulletins CONTACT:
D. L. Caphton (215-337-5266) cc w/encls:
W. T. Ullrich, Station Superintendent Troy B. Conner, Jr., Esquire i
Eugene J. Bradley, Esquire Raynond L. Hovis, Esquire l
Michael J. Scibinico, II, Assistant Attorney General l
8000120103
ENCLOSURE 1 SSINS:
6820 Accession No.:
8006190074 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 August 22, 1980 IE Supplement 3 to Bulletin No. 80-17:
FAILURE OF CONTROL RODS TO INSERT DURING A SCRAM AT A BWR NRC staff cvaluation of a potential single failure mechanism of the control rod drive control air system has identified the need for licensee actions in addition to those requested by IEB 80-17 and Supplements 1 and 2.
~
The potential single failure was discussed in IE Information Notice 80-30, which was issued on August 19, 1980.
It involves gradual or partial loss of control air system pressure, which could cause partial opening of scram outlet valves without rod motion.
The resultant accumulated seal leakage could conceivably fill the scram discharge volume in a few minutes.
Since not all operating BWR's have instrumentation presently installed to continuously indicate water level in the scram discharge volume headers and to provide a control room alarm or scram function, the possibility exists for the scram discharge volume to fill to a level which could prevent reactor scram before automatic protective action or before the operators could be warned.
In view of the possible single failure mechanism described above, the following actions are requested in addition to those specified in IE Bulletin 80-17, Supplements 1 and 2:
1.
For those plants in which the scram discharge volume headers are connected to the instrument volume by a 2 inch pipe, within five days of the date of this Bulletin, provide or verify that procedures are in effect to:
a.
Require an immediate manual scram on low control rod drive air pressure with a minimum 10 psi margin above the opening pressure of the scram outlet valves.
b.
Require an immediate manual scram in the event of:
(1) Multiple rod drift-in alarms, or (2) A marked change in the number of control rods with high temperature alarms.
Installation of water level instrumentation in the scram discharge volume with level alarm and continuous level indication in the control rocm, in response to Item B.1 of IEB 80-17 Supplement Nc. 1, may provide a basis for relaxation of the time for initiating a manual scram.
IE Bulletin No. 80-17 August 22, 1980 Supplement No. 3 Page 2 of 2 2.
In addition, every BWR licensee is requested within five days of the date of this bulletin to provide and implement procedures which require a functional test using water for the instrument volume level alarm, rod block and scram switches after each scram event, before returning to power.
This procedure should remain in effect until modifications in addition to Item B.1 of IEB 80-17 supplement No. I are completed to substantially increase reliability of water level indication in the scram discharge volume (s).
Licensees of all operating BWRs shall submit a report summarizing action taken in response to the above items within 10 days of the date of this Bulletin Supplement.
Accordingly, you are requested to provide within 10 days as specified above, written statements of the above information signed under oath or affirmation.
Reports shall be submitted to the Director of the appropriate NRC Regional Office and a copy forwarded to the Director, Division of Reactor Operations Inspection, NRC.
Office of Inspection and Enforcement, Washington, D.C.
20555 Approved by GAO, B180225 (R0072); clearance expires July 31, 1980. (Application for renewal pending before GA0.) Approval was given under a blanket clearance specifically for identified generic problems.
Supplement 3, IE Bulletin No. 80-17 August 22, 1980 RECENTLY ISSUED IE BULLETINS Bulletin Subject Date Issued Issued To No.
80-20 Failures of Westinghouse 7/31/80 All holders Type W-2 Spring Return of a power to Neutral Control Switches reactor OL or CP Revision 1 Failures of Mercury-8/15/80 All holders to 80-19 Wetted Matrix Relays in of a power Reactor Protective Systems reactor OL of Operating Nuclear Power or CP Plants Designed by Combustion Engineering 80-19 Failures of Mercury-7/31/80 All holders of Wetted Matrix Relays in a power reactor Reactor Protective Systems OL or CP of Operating Nuclear Power Plants Designed by Combustion Engineering 80-18 thintenance of Adequate 7/24/80 All holders of Minimum Flow Thru Centrifugal a PWR power Charging Pumps Following reactor OL Secondary Side High Energy and hciders Line Rupture of a PWR Construction Permit nearing licensino.
Supplement 2 Failures Revealed by 7/22/80 All holders of to 80-17 Testing Subsequent to a BWR power Failure of Control Rods reactor OL or to Insert During a Scram CP at a BWR Supplement 1 Failure of Control Rods 7/18/80 All holders of l
to 80-17 to Insert During a Scram a BWR power l
80-17 Failure of Control Rods 7/3/80 All holders of I
to Insert During a Scram a BWR oower reactor l
at a BWR OL or CP 80-16 Potential Misapplication of 6/27/80 All holders of a Rosemount Inc., Models-1151 power reactor and 1152 Pressure Transmitters OL or CP with Either "A" or "D" Output Codes
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