ML20137Y722

Technical Issue Summary RI-94-04, Pressurizer Safety Valves & Solid Plant Operation

ML20137Y722
Person / Time
Site:	Salem
Issue date:	06/16/1994
From:	Haverkamp D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20137X493	List: ML20137X488 ML20137X514 ML20137X530 ML20137Y722
References
FOIA-96-351 RI-94-04, RI-94-4, NUDOCS 9704230193
Download: ML20137Y722 (2)

Text

- - --. - . ._ -- . ._ ~. .-~

O <ttu

'y e 4 UNITED STATES g g NUCLEAR REGULATORY COMMISSION L 8 REGloN 1 g 475 ALLENDALE ROAD g . . . . . g[4 KING oF PRUSSIA, PCNNSYLVANIA 19406-1415 No: RI-94-04 TECHNICAL ISSUE

SUMMARY

Date: 6/16/94 PRESSURIZER SAFETY VALVES AND SOLID PLANT OPERATION PROBLEM: On April 7,1994, at the Salem Nuclear Generating Station, an inadvertent actuation of the emergency core cooling system (ECCS) occurred following a plant trip. As a result of the safety injection the pressurizer became water solid and the power operated relief valves (PORVs) cycled over a hundred times each ,

to control reactor coolant system (RCS) pressure and thereby precluded the need for opening of the pressurizer code safety valves from a water solid condition. The Salem overpressure protection systems consist of three (3) safety valves, two (2) PORVs, and two (2) PORV block valves. The safety valves are 6-in. Crosby Model HB-BP-86,6M6, spring-loaded valves with loop seal internals. The primary code safety valves received post-TMI qualification testing per NUREG-0737, Action Item 2.D.1. That testing demonstrated that safety valve operation with subcooled water could lead to unpredictable component performance. (Each licensee has received an SER covering the operation of PORVs and safety valves.) If the safety valves are challenged on niore than a single operation during solid plant conditions, the event may degrade to a loss of coolant accident if the safety valves stick open. Also, Salem technical specifications permit operation with the PORV block valves shut to stop PORV seat leakage, however, the emergency operating procedures (EOPs) do not provide direction to the plant operators to open the block valves during such transients as occurred on April 7,1994, thereby increasing the probability of lifting a code safety valve with subcooled water.

EVALUATION: Westinghouse Nuclear Safety Advisory Letter (NSAL)93-013 identifies that potentially non-conservative assumptions may have been used in the licensing analysis of the Inadvertent Operation of the ECCS at Power accident. The use of revised assumptions could cause a water solid condition in less than the 10 minutes generally assumed for operator action time to terminate the ECCS flow. If the PORVs were blocked, the safety relief valves would relieve water and potentially cause the accident to degrade from a Condition II (a fault of moderate frequency) to a Condition IIIincident (infrequent small break LOCA incident) without other incidents occurring independently.

LICENSEE /NRC ACTION: PSE&G is continuing to evaluate this information and the potential impact of the adequacy of their accident analysis. An AIT was dispatched to the site following the April 7 event. An Information Notice is being prepared to discuss the damage to the PORVs found subsequent to the event.

Additional generic communications are also being considered regarding the Salem April 7 event.

CONTACTS: Robert Summers (610) 337-5189 Charles Marschall (609) 935-5151

REFERENCES:

IR 50-272/94-80; Westinghouse NSAle93-013; LER 50-272/94-007-01 ORIGINAL SIGNED BY WAYNE LANNING FOR:

Donald R. Haverkamp Technical Assistant Division of Reactor Projects 9704230193 970411 PDR FOTA b OfNEILL96-351 PDR

p Karp

'y 1 UNITED STATES g g NUCLEAR REGULATORY COMMIESION 8 REGION I E

C 475 ALLENGALE ROAD

%, KING OF PRUSSIA, PENNSYLVANIA 19406-1415 Distri$dttd$:(via E-Mall):

T. Martin, RA W. Kane, DRA W. Dean, OEDO J. Calvo, NRR F. Gillespie, NRR B. Grimes, NRR A. Chaffee, NRR R. Baer, RES K. Raglin, AEOD E. Merschoff, RII E. Greenman, RIII A. Beach, RIV K. Abraham, PAO J. Wiggins, DRS A. Blough, DRS J. Joyner, DRSS DRP Staff D. Screnci, PAO J. Stone, PM, NRR DRS SCs  !

C. Miller, NRR J. Rosenthal, AEOD j l

l 1 609 987 6356 16:51 No.005 P.01 TEL:1-609-987-6356 May 20.94

DEP BNE L

i 9

5 tate of New Jersey Departenent of IJwironsmental Protection and Energy Divisdon of Environmontal Safiety, Health Q.M

~ v.)

S Robert C. 5Nna. Jr.

Cornmissioner and Analytical Programs RadL1 tion FWdren Programs ho%/49(g) o

, % fg. '

CN 42 N Trenton, N.J. 08625-0415

[/#

JgU/ck Tel (609) 987-6389 Fax (609) 987-6390 Afp /

b o f

May 20, 1994 kh- ,

l G l i

Mr. James T. Wiggins, Acting Director i Division of Reactor Safety 1 - U.S. Nuclear Regulatory Commission I

g 475 Allendale Road

. King of Prussia, PA 19406

Dear Mr. Wiggins:

l Salem Unit 1 Augmented Inspection Team Subject In accordance with the provisions of the July 1987 Memorandum of Understanding between the Nuclear Regulatory Commission (NRC) and the New Jersey Department of Environmental Protection and Energy (DEPE) , the DEPE is providing feedback regarding the April 7, 1994 Alert at Salem Unit 1 and the subsequent NRC Augmented Inspection Team (AIT). As you know, the New Jersey DEPE's Bureau of Nuclear Engineering (BNE) observed part of the performance of ,

the AIT. In keeping with the spirit of the agreement between the l DEPE and the NRC, the DEPE will not disclose its inspection observations to the public until the NRC releases its final AIT report.

This participation was especially valuable for our nuclear engineering staff. It allowed us to gain immediate understanding of the actual events and plant conditions leading to the Alert declaration on April 7. ThLs information has been shared with DEPE management. Our representatives were impressed with the diligence of the AIT members and their ability to expeditiously sift through a complex series of events. The AIT Team Leader was extremely cooperative and open to our representatives' questions and g

concerns. All team members had inquisitive attitudes, allowing for

)

effective information gathering from PSE&G and analysis within the team.

NewJerseyis en Cqual Oprtunity in1ployer Re<yded rapw

~ Ot4T7Fon O 09 i

- DEP.BNE TEL:1-609-987-6356 May 20,94 16:52 No.005 P.02

j. .

Page 2 I

1-

! We are continuing to review all available information i concerning the Alert. Overall, the information we have seen is

! consistent with our observations of the AIT. The May 10, 1994 internal memorandum from Mr. Martin, NRC Regional Administrator, to l Mr. Taylor, NRC Executive Director of Operations, clearly 1

described the chain of events and the results of the operator interviews. We have two specific subjects we have not seen

. addressed in the information made available to date and we have one j',

general concern.

4 First, the NRC and PSE&G have stated that spurious high steam i flow signals have been experienced before at Salem Units 1 and 2.

i We understand that other Westinghouse units have experienced this problem as well. We are concerned that these past spurious signals

! have not been shared within the industry or if it was shared, there i stay be a weakness in PSE&G's ability to evaluate industry experience. If the AIT is not assessing this matter, we recommend

!I

=

follow-up through the inspection process.

Second, following the first safety injection on' April 7, l

l operators reported that trouble alarms were received on all three i diesel-generators and an urgent trouble alarm was received on one

of the diesel-generators. An SRO was dispatched to the diesel-4 generators. He found all diesels operating properly and reset the i alarm which was attributed to low starting air pressure. We j recognize this is unrelated to the events that led to the j7 declaration of the Alert. However, it may indicate that a problem j) exists with the diesel-generators that operators have learned to r cope with. Certainly, responding to an urgent trouble alarm in an ,

emergency situation is a distraction that should be avoided. l Third, our general concern involves an apparent inconsistency in statements made by NRC senior management and the results of the ,

previous two SALP periods. NRC has expressed concern with long- l standing cultural and equipment problems at Salem Units 1 and 2.

The results of the previous SALP reports are not consistent with

} these observations. In fact the latest SALP report indicates some improvement. We are concerned over the effectiveness of the SALP process to reflect the true assessment of this utility's performance. Perhaps we could discuss this issue at an appropriate time.

1 6

~ ~

TEL:1-609-987-6356 May 20.9h 16I52 $5.605 P.'O'3' DEP'.BNE Page 3 If you have f.ny questions, please contact me at (609) 987-2189.

' arely,'

• Anthon J. McMahon t ng '

Acting Assistant Di or, Radiatich Protection Element,

' DEPE i

c: Kent Tosch, Manager, DEPE Dave Chawaga, SLO, NRC

Attachment:

DEPE/NRC MOU i

i l

l 3

s A

1 s

DEPrBNE TEL:1-609-987-6356 May 20.94 16:52 No.005 P.04 j

D#M

!,. '14 '87 15 11 HRC KING OF PRUSSIA-2 P02

.f. . ...,,k uamrea states '

j j i NUCLEAR REGULATORY COMMISSION

- - nacioni att #ARE AVENut j

{

et tese op equggiA, pggggyLVAMA 164Ee 1

i Richard T. Dewitng, Ph.D., P.E. ,

l 4 Commissioner

! Department of Environmental d Protection l' 401 East state street CN 402 a Trenton, New Jersey 08625

)

Dear commissioner Dowling:

i This letter is to confirm the general agreement reached as the result of our

! ' meetings with Dr. Berkowitz and his staff regarding the surveillance of the nuclear power plants operating in New Jersey. During those meetings we agreed

!' that there was a need to have a more formal way of coordinating NRC and State

! activities related to plant operations and that the Department of Environmental l Protection's Bureau of Nuclear Engineering (BNE) will be the int'erface with .the j NRC on a day to-day basis.

1 i The areas addressed by this letter are:

i .

1. State attendence at NRC meetings with licensees relative h to licensee performance, including; enforcement conferences, li plant inspections and licensing actions. .

I 2. NRC and SNE exchanges of information regarding plant con-ditions or events that have the potential for or are of j safety significance.

4 l We agree that New Jersey officials may attend, as observers, NRC enforcement j conferences and NRC meetings with licensees, including Systematic Assessment of i Licensee Performance ($ ALP) reviews. with respect to nuclear power plants il operating in N.w Jersey (PSEM, GPUN). We shall give timely notification to the BNE of such meetings, including the issues expected to be addressed.

Although I de not expect such cases to arise frequently, we must reserve the right to close any enforcement conference that deals with highly sensitive safeguards material or information that is the subject of an ongoing investi-

gation by the NRC Office of Investigation (OI), where the premature disclosure of information could jeopardite effective reguletory action. In such cases, we

! would brief you or your staff after the enforcement conference and would j expect the $ tate to maintain the Confidentiality of the briefing.

41 l With regard to NRC inspections at nuclear power plants in New Jersey, we agree i that the SNE staff may accompany NRC inspectors to observe inspections. To the

extent practicable, NRC will advise the State sufficiently in advance of our inspections such that State inspectors can make arrangements to attend. In i

order to assure that those inspections are effective and meet our mutual needs, j 1 suggest the following guidelines:

i

DEP.BNE TEL:1-609-987-6356 May 20.94 16:b6 NO.UUb P.Ub f'f ' rm 14 *87 15 11 NRC KING OF PRUSSIR-2 P03 1

i i 2 2

I l 1. The State of New Jersey will make arrangements with the i licensee to have New Jersey participants in NRC inspec-l tions trained and badged at each nuclear plant for unescorted access in accordance with utility requirements.

2. The State will give NRC adequate prior notification when

! planning to accompany NRC inspectors on inspections.

3. Prior to the release of NRC inspection reports, the State i

will exercise discretion in disclosing to the public its observations during inspections. When the conclusions or observations made by the New Jersey participants are sub- -

! stantially different from those of the NRC inspectors, New Jersey will make their observations available in ,

writing to the NRC and the licensee. It is understood that these coautunications will become publicly available i

1, j;

along with the NRC inspection reports. l j With regard to communications, we agree to the following: ,

i I 1. The NRC shall transmit technical Information to SNE relative j to plants within New Jersey concerning operations, design, external events, etc. ; for issues that alther have the potential for or are of safety significance, i 2, The NRC shall transmit all Preliminary Notifications related i to nuclear plant operations for New Jersey facilities to the ,

8NE routinely.

3. The 6NE shall comunicate to the NRC any concern or question regarding plant conditions or events, and any State information about nuclear power plants.

Please let me know if these agreements are satisfactory to you..

l Sincerely, h.T - 4Y W{111ae T. Russell Regional Administrator 1