ML19260E110
| ML19260E110 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 01/28/1980 |
| From: | Reid R Office of Nuclear Reactor Regulation |
| To: | Arnold R METROPOLITAN EDISON CO. |
| References | |
| NUDOCS 8002130375 | |
| Download: ML19260E110 (8) | |
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Jcnuary 28, 1980 Docket No. 50-289 Mr. R. C. Arnold Senior Vice President Metropolitan Edison Company 100 Interpace Parkway Parsippany, New Jersey 07054
Dear Mr. Arnold:
RE: Containment Purging and Venting During Normal Operation By letter dated November 29, 1978, the Commission (NRC) requested all licensees of operating reactors to respond to generic concerns about containment purging or venting during normal plant operation. The generic concerns were twofold:
(1) Events had occurred where licensees overrode or bypassed the safety actuation isolation signals to the containment isolation valves.
These events were determined to be abnormal occurrences and reported to Congress in January 1979.
(2) Recent licensing reviews have required tests or analyses to s'.ow that containment purge or vent valves would shut without degrading con-tainment integrity during the dynamic loads of a design basis loss of coolant accident (DBA-LOCA).
The NRC position of the November 1978 letter requested that licensees take the following positive actions pending completion of the NRC review:
(1) prohibit the override or bypass of any safety actuation signal which would affect another safety actuation signal; the NRC Office of Inspection and Enforcement would verify that administrative controls prevent improper manual defeat of safety actuation signals, and (2) cease purging (or venting) of containment or limit purging (or venting) to an absolute minimum, not to exceed 90 hours0.00104 days <br />0.025 hours <br />1.488095e-4 weeks <br />3.4245e-5 months <br /> per year.
Licensees were requested to demonstrate (by test or by test and analysis) that containment isolation valves would shut under postulated DBA-LOCA condition. The NRC positions were amplified by citation (and an attached copy) of our Standard Review Plan (SRP) 6.2.4 Revision 1 and the associated Branch Technical Position CSB 6-4, which have effectively classed the purge and vent valves as
" active" invoking the operability assurance program of SRP 3.9.3.
The NRC staff has made site visits to several facilities, has met with licensees at Bethesda, Maryland, and has held telecon conferences with many other licensees and met with some valve manufacturers.
During these discussions, the NRC staff has stressed that positive actions must be taken as noted above to assure that containment integrity would be maintained in the event of a DBA-LOCA.
80021303 7 5
Mr. R. C. Arnold January 28, 1980 As a result of these actions, we have learned from several licensees that at least three valve vendors have reported that their valves may not close against the ascending differential pressure and the resulting dynamic loading of the design basis LOCA. All identified licensees who are affected have proposed to maintain the valves in the closed position or to restrict the angular opening of the valves whenever primary containment integrity is required under the DBA-LOCA condition.
Recently, a report under 10 CFR Part 21 was received by the NRC from the manu-facturer of butterfly valves which are installed in the primary containment at the Three Mile Island Unit 2 Nuclear Station. These butterfly valves are used for purge and exhaust purposes and are required to operate during accident conditions. The report discusses the use of an unqualified solenoid valve for a safety-related valve function which requires operation under accident conditions.
The solenoid valve is used to pilot control the pneumatic valve actuators which are installed on the containment ventilation butterfly valves at this facility.
Your re-evaluation of valve performance for conditions noted in the previous para-graph must consider the concerns identified in IE Bulletin 79-01A.
As the NRC review progresses, licensees which might have electrical override circuitry problems are being advised not to use the override and to take compen-satory interim measures to minimize the problem.
To assure early resolution of this issue, we believe a commitment from you is required at this time. This is the case, even though you may have proposed Technical Specification changes or other long or short-term measures, which we are reviewing.
For your use, we have provided as an attachment, an interim NRC staff position.
In addition, our recently developed " Guidelines for Demonstration of Operability of Purge and Vent Valves" were provided by separate letter to licensees of each operating reactor.
Because of the potential adverse effects on the public health and safety which could result from the postulated, DBA-LOCA while operating with open purge or vent valves, we believe your response to this letter is required.
You are requested to inform us in writing within 45 days of receipt of this letter of your commitment to operate TMI-1 upon restart in conformance with the enclosed interim position.
You are also urged to expedite the submittal of the information regarding the operation capability of your purge valves which you have comitted to provide by April 30, 1980.
Sincerely, k
Y.
Robert W. Reid, Chief Operating Reactors Branch #4 Division of Operating Reactors
Enclosure:
Interim Position for Containment Purge and Vent Valve Operation cc: w/ enclosure See next page
Metropolitan Edison Company 1
Dr. Walter H. Jordan 881 W. Outer Drive Oak Ridge, Tennessee 37830 cc w/nnelesum(s):
Mr. l'a rvin I. Lewis Dr. Linda W. Little 6504 Bradford Terrace.
5000 Hermu,tage Drive P,hil a del phia,
Pennsylvania 19149 Raleigh, North Carolina 27612 Walter W. Cohen, Cons mer Advocate Holly S. Keck Department of Justice Anti-fiuclear Group Representing Strawberry Square,14th Floor York Harrisburg, Pennsylvania 17127 245 W. Philadelphia Street York, Pennsylvania 17404 RoLert L. Knupp, Esq.
Assistant Solicitor John Levin, Esq.
Y,nupp and Andrews Pennsylvania Public Utilities Comm.
P.O. Box P Box 3265 407 N. Front Street Harrisburg, Pennsylvania 17120 Harrisburg, Pennsylvania 17108 Jordan D. Cunningham, Esq.
Ahn E. Minnich, Chairman Fox, Farr and Cunningham Dauphin Co. Board of Commissioners 2320 North 2nd Street Dauphin County Courthouse Harrisburg, Pennsylvania 17110 Frtnt and Market Sts.
Harrisburg, Pennsylvania.17101 Theodore A. Adler, Esq.
WIDOFF REAGER SELK0WITZ & ADLER Atomic Safety and Lice ~nsing Appeal Board Post Office Box 1547 U.S. Nuclear Regula tory Commission Harrisburg, Pennsylvania 17105 Washington, D. C.
20555 Ms. Marjorie M. Aamodt Atomic Safety and Licensing Board Panel R.D. #5 U.S. Nuclear Regulatory Commission Coatesville, Pennsylvania 19320 Washington, D. C.
20555 Ms. Karen Sheldon Sheldon, Harmon, Roisman & Weiss Docketing and Service Section 1725 I Street, N. W.
U.S. Nuclear Regulatory Commission Suite 506 Washington, D. C.
20555 Washington, D. C.
20006 Robert Q. Pollard Earl B. Hoffman Chesapeak Energy Alliance Dauphin County. Comissioner 609 Montpelier Street Dauphin County Courthouse Baltimore, Maryland 21218 Front and Market Streets Chauncey Kepford Judith H. Johnsrud Ellyn Weiss, Esq.
Environmental Coalition on Nuclear Power Sheldon Harmon, Roisman & Weiss 433 Orlando Avenue 1725 I 5treet, N.W.
State rollege, Pennsylvania 16801 Mn n, D.C.
20006 Ms. t rieda 53erryhill, Chairman Mr. Steven C. Sholly Coalition for Nuclear Power Plant 304 South Market Street Postponement Mechanicsburg, Pennsylvania 17055 2610 Grendon Drive Wilmington, Delaware 19808 Mr. Thomas Gerusky Mrs. Rhoda D. Carr Bureau of Radiation Protection 1402 Marene Drive Department of Environmental Resources P.O. Box 2063 Harrisburg, Pennsylvania 17109 Harrisburg, Pennsylvania 17120
Karin W. Carter, Esq.
505 Executive House P. O. Box 2357 Metropolitan Edison Company Harrisburg, Pennsylvania 17120 Honorable Mark Cohen 512 E-3 Main Capital Building Harrisburg, Pennsylvania lH2O cc w/ enclosure (s):
G. F. Trowbridge, Esquire Dauphin County Of fice Emergency Shaw, Pi ttnan, Potts & Trowbridge Preparedness 1800 M Street, N.W.
Court House, Room 7 Washington, D. C.
20036 Front & Market Streets Harrisburg, Pennsylvania 17101 GPU Service Corporation Richard U. Heward, Project Manager Mr. E. G. Wallace Department of Environmental Resources Licensing Manager ATTN:
Director, Of fice of Radiological 260 Cherry Hil.1 Road Heal th Parsippany, New Jersey 07054 Post Of fice Box 2063 Harrisburg, Pennsylvania 17105 Pennsylvania Electric Company Mr. R. W. Conraa Director, Tecnnical Assessment Vice President, Generation Division 1001 Broad Street Office of Radiation Programs Johnstown, Pennsylvania 15907 (AW-459)
U. S. Environmental Protection Agency Miss Mary V. Southard, Chairman Crystal Mall #2 Citizens for a Safe Environment Arlington, Virginia 20460 Post Of fice Box 405 Harrisburg, Pennsylvania 17108 Mr. Robert B. Borsum Babcock & Wilcox Government Publications Section Nuclear Power Generation Division State of Library of Pennsylvania Suite 420, 7735 Old Georgetown Road Box 1601 (Eaucation Building)
Bethesda, Maryland 20014 Harrisburg, Pennsylvania 17126
- Ivan W. Smith, Esq.
Pr. David D. Maxwell, Chairman Atomic Safety & Licensing Board Panel Board of Supervisors U.S. Nuclear Regulatory Commis sion Lonaonderry Township Washington, D. C.
20555 RFD=1 - Geyers Church Road Mi ddletown, Pennsylvania 17057 U. S. Environmental Protection Agency Region III Of fice ATTH:
EIS COORDINATOR Governor's Off'ce of State Plannino Curtis Building (Sixth Floor) and Development 6th and Walnut Streets ATTH:
Coordinator, Pennsylvania Philadelphia, Pennsylvania 19106 State Clearinghouse Mr. J. G. Herbein P. O. Box 1323 Vice President Harrisburg, Pennsyl vania 17120 Metropolitan Edison Company P. O. Box 480 Middletown, Pennsylvania 17057 Ms. Jane Lee P.. D. 3; Box 3521 Etters, Pennsylvania 17319
INTERIM POSITION FOR CONTAINMENT PURGE AND VENT VALVE OPERATION PENDING RESOLUTION OF ISOLATION VALVE OPFRABILITY Once the conditions listed below are nec, restrictions on use of the containment purge and vent systen isolation valves will be revised based on our review ei your responses to the November 1978 letter justifying your proposed operational mode. The revised restrictions can be established separately for each systen.
1.
Whenever the containuent integrity is :"> quired, emphasis should be placed on operating the containment in a assive mode as much as possible r
and on limiting all purging and venting times to as low as achievable.
To justify venting or purging, there must be an established need to improve working conditions to perform a safety related surveillance or safety related maintenance procedure.
(Examples of improved working conditions would include deinerting, reducing tenperature*, humidity *,
and airborne activity sufficiently to pernit efficient performance or to significantly reduce c cupational radiation exposures), and 2.
Maintain the containment purge and vent isolation valves closed whenever the reactor is not in the cold shutdown or refueling node until such time as you can show that:
a.
All isolation valves greater than 3" nominal diameter used for containment purge and venting operations are operable under the nost severe design basis accident flow condition loading and can close within the time limit stated in your Technical Specifications, design criteria or operating procedures. The operability of butter-fly valves may, on an interin basis, be demonstrated by limiting the valve to be no nore than 30 to 50 open (90 being full open).
The naximun opening shall be determined in consultation with the valve supplier. The valve opening must be such that the critical valve parts will not be damaged by DBA-LOCA loads and that the valve will tend to close when the fluid dynamic forces are introduced, and b.
Modifications, as necessary, have been made to segregate the cnntainnent ventilation isolation signals to ensure that, as a ninimuii, at least one of the automatic safety injection actuation signals is ur. inhibited dnd operable to initiate valve closure when any other isolation signal nay be blocked, reset, or overridden.
iily wliTr'e Temperature and huuidity controls are not in the present design.
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