ML20054F716

Testimony of DG Bridenbaugh & Gc Minor on Behalf of Suffolk County Re County Contention 28(a)(vi) & Shoreham Opponents Coalition Contention 7a(6) on Reduction of Safety Relief Valve Challenges.Certificate of Svc Encl

ML20054F716
Person / Time
Site:	Shoreham File:Long Island Lighting Company icon.png
Issue date:	06/14/1982
From:	Bridenbaugh D, George Minor SUFFOLK COUNTY, NY
To:
Shared Package
ML20054F708	List: ML20054F707 ML20054F716
References
ISSUANCES-OL, NUDOCS 8206170244
Download: ML20054F716 (16)

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e UNITED STATES OF AMERICA -

NUCLEAR REGULATORY COMMISSION 'd2 c1'; 15 A'iO 'd BEFORETHEATOMICSAFETYANDLICENSIhGNARD;[' 2

• In the Matter of LONGISLANNLIGHTCOMPANY )

Docket No. 50-322 (0.L.)

(Shoreham Nuclear Power Station )

Unit 1) ) ,

PREPARED DIRECT TESTIMONY OF DALE G. BRIDENBAUGH AND GREGORY C. MINOR ON BEHALF 0F SUFFOLK COUNTY REGARDING SUFFOLK COUNTY CONTENTION 28(a)(vi)

AND SOC CONTENTION 7A(6)

REDUCTION OF SRV CHALLENGES JUNE 14, 1982 1

8206170244 820614 PDR ADOCK 05000322 T PDR

SUMMARY

OF TESTIMONY ON REDUCTION OF SRV CHALLENGES LILCO has failed to adequately resolve the issue of reduction of SRV Challenges, address'ed in NUREG-0737, Clarification of TMI Action Plan Requirements. NUREG- 07 37 directed all licensees and applicants to consider ways by which challenges and. failures of relief valves could be reduced. It also required implementation of those improve-ments that reduced relief valve challenges without compromising performance of relief velves or other systems. In response to this requirement, LILCO j oined in a collective effort with the BWR Owners Group to produce a generic evaluation of this issue and claimed individually to have made several a'dditional changes and improvements at Shoreham to fulfill the requirement.

LILCO's response to NUREG-0737 does not adequatelv ,

satisfy the NRC's SRV challenge directive. First, while LILCO has pursued improved reliability of SRV's , it has not complied with the specific action item requirements which state that improvements should be made by the reduction of challenges. Second, because Shoreham's Target Rock valves were selected before this task was identified and cannot be considered an improvement resulting from the NRC order, LILCO has attempted to justify the existing equipment despite t

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i the NRC's directive that improvements rather than j ustificatiods be made. And third, the specific improvements that LILCO claims for Shoreham, along with the challenge and failure reductions .

listed in the FSAR, do not meet requirements and do not appear to be substantiated.

Finally, LILCO has not met the requirements of the TMI Action Plan in that it has only made an improvement by a factor of 3 over the worst case BWR, as opposed to an improvement factor of 10, presumably over the whole population of BWR's.

Accordingly, additional improvements should be identified and implemented.

Attachments

1. NUREG-0737, Clarification of TMI Action Plan Requirements pp. II.K.3.16-1 thru 3.

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PREPARED DIRECT TESTIMONY OF DALE G. BRIDENBAUGH AND GREGORY C. MINOR REGARDING SUFFOLK COUNTY CONTENTION 28(a)(vi) AND SOC 7A(6)

REDUCTION OF SRV CHALLENGES Q: Please state the names and positions of the authors of this testimony.

A: This testimony was co-authored by Dale G. Bridenbaugh and Gregory C. Minor. Both are employees .of MHB Technical Associates and consultants to Suffolk County (SC) . Our qualifications have previously been submitted to the Board.

Q: What is the purpose of this testimony?

A: The purpose of this testimony is to address the issues raised by SC Contention 28(a)(vi) and the same concerns raised by SOC 7A(6) . Suffolk County Contention 28(a)(vi) l states:

Suffolk County contends that the NRC Staff has not adequately assessed and LILCO has not ade-quately resolved, both singularly and cumulatively, the generic unresolved issues applicable to a BWR of the Shoreham design. As a result, the Staff has not required the Shoreham structures, systems, and components to be backfit to current regulatory practices as required by 10 CFR 50. 5 5 (a) , 50. 57, and 50.109, with regard to the following :

(a) LILCO has failed to resolve adequately certain generic safety items identified as a result of the TMI-2 accident and contained in NUREG-0737, Clarification of TMI Action Plan Requirements (1980.

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(vi) LILCO hopes to accomplish a reduction

• in challenges to-safety / relief valves (NUREG-0737, Item II.K.3.16) by procedural techniques, rather than by system modifications. But the relia- .

bility of the SRV's chosen for Shoreham has been historically poor. Thus, LILC0 has not demonstrated SRV compli-ance with 10 CFR Part 50, Appendix A, Criterion 30.

Q: What is the origin of this concern?

A: In response to' -the TMI-2 accident investigation, the NRC directed all licensees and applicants to consider ways by which challenges and failures of relief valves could be reduced. This direction was documented in NUREG-0737, Clarification of TMI Action Plan Requirements.

Q: What specifically does NUREG-0737 require in this regard?

A: Task II.K.3.16 suggests that challenge and failure rate reduction can be accomplished through consideratien of 13 different changes. It further directs that: ,

"those changes which are shown to reduce relief-valve challenges without compromising the performance of the relief valves or other systems should be implemented."

and that:

" Challenges to the relief valves should be reduced i suostantially (by an order of magnitude) ." 1/

A copy of the NUREG-0737 section relevant to this issue is appended as Attachment 1.

1/ NUREG-0737, p. 3-156, emphasis added.

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Q: What has been LILCO's response to this requirement? '

A: LILCO joined with a BWR Owners Group for a generic evaluation of this issue. As rhported in the FSAR .

(page II.K. 3.16-2 5 3), LILC0 has adopted this generic evaluation. Changes claimed for Shoreham are the use of 2-stage Target Rock valves, operator training to limit second and subsequent SRV openings during a transient and commitment to an improved pneumatic supply control system.

Q: Does this action satisfy the intent of the NRC's SRV challenge directive?

A: In our opinion it does not.

Q: Why not?

A: For the following reasons :

(1) First, the action plan directed that improvements should be made by the reduction of challenges.

All of the 13 changes suggested in NUREG-0737 were aimed at reducing the duty on the valves, not towards improved reliability of the SRV's.

While valve reliability is important and desirable, it alone does not comply with the specific word.s of the action item.

(2) Second, the use of the 2-stage Target Rock valve at Shoreham was not a change resulting from this 1

evaluation but rather was intended for use at Shoreham since before this task was identifie.1. Additionally, the NRC recognized the limited value of this type of unproven modification by stating that:

"The operating history of the SRV has been poor. A new design is used in some plants but the operational history is too brief to evaluate the effectiveness of the new design." 2/

The NRC directive says that improvement should be made, rather than justification for existing equipment. What LILCO has done is compare Shoreham with the worst BWR plant design. Just because Shoreham is expected to be ,

better than the worst does not mean it has complied with the directive which requires reduction of challenges.

Q: How has LILCO's dependence on a valve of unproven reliability affected the quality of Shoreham's reactor coolant pressure boundary?

A: Target-Rock valve performance has been historically poor. Since LILCO has relied so heavily on reliability improvements, we conclude that the quality of the reactor coolant pressure boundary has not been assured as required by 10 C.F.R. 50, Appendix A, GDC

30. Further, LILCO's failure to demonstrate compliance with the NUREG-0737 item is additional evidence of its f ailure to comply with GDC 30.

Q: Do you find any other discrepancies, including those relating to NUREG-0737, with the action proposed at Shoreham?

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l 1/ Page II.K.3.16-2, Attachment 1.

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A: Yes wa do. LILCO claims throo improvsmants exist (or will oxist) at Shoroham. These, along with the challengo and failure reductions listed in the FSAR, are: ,

Modification Reduction' Factor 2-Stage Target Rock 0.5

" Low-Low set" equivalent action 0.44 Pneumatic control improvement 0.98 Even assuming that the reduction factors are correct, '

since these factors are additive (equal to the product of the three) they provide only a challenge reduction .

factor of 0.22. This is twice as large as.(or only one-half as effective as) the order of magnitude improve-ment required (reduction factor of 0.1).

Q: Do you agree with the reduction factors claimed?

A: No, they do not appear to be substantiated. The improve-ment to be gained by use of the 2-stage valve, for example, has yet to be verified through operating experience and it may not be as effective as hoped. A recent study (published February 1982) of relief valve performance conducted by Southwest Research s tates :

"At the present time, the two-stage modifi-cation has been installed at the Browns Ferry Plant which, as would be indicated by the reliability function evaluation of dominant failure cause, does not appear to have increased ,

valve reliability." 3/

There fore .it may be premature to claim a 50% reduction for the use of this valve. Since the Owners Group evaluation sugges ted a reduction factor of 0. 4 to 0.6,

-3/ An Analysis of the Reliability of Light Water Reactor Power- Actuated Pressure Relieving Valves and Safety (Relief)

Valves and Their Component Parts Using the Nuclear Plant Reliability Data System (NPRDS) - Final Report , pp. 27-28.

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it would seem more appropriate to use a factor in the O.6 range; a conservative assumption in view of the lack of data supporting a reduction factor of 0.5. .

Q: What about the operator action required to reduce subsequent valve operations?

A: This also appears to be non-conservatively assessed.

Since such action would have to be taken in a relatively short time (a few minutes) and under stressful conditions, it does not seem appropriate to equate a required operator action with an automated modification. LILC0 takes credit for a reduction of 0.44 for this modification, from a possible improvement range of 0.23 to 0.62 for either automated or manual fix. It would seem more fitting to use a factor closer to the upper end of the range.

Q: What total reduction factor do you believe might be better used in describing the Shoreham plant when compared to the reference BWR 4 design used in the Owners Group evaluation?

A: Assuming a 2-stage valve factor of 0.6, an operatcr manual action factor of 0.6, and a pneumatic control factor of 0.98, it would appear a stuck open relief valve at Shoreham might occur at a rate of 0.35 when l compared to the reference BWR-4. This is only an 1

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.s improvement by a factor of three over the worst case '

BWR. The TMI action plan calls for an improvement of a factor of ten, presumably over the whole population ,

o f BWR's. -

Q: Has LILC0 then demons trated compliance with the SRV challenge reduction requirement?

A: No, LILCO has not and the requirements of GDC-30, quality of reactor coolant pressure boundary, have accordingly not been met. Additional improvements should be identified and implemented. For example, each of the thirteen potential changes listed in NUREG-0737 should be uniquely evaluated for Shoreham and modifications should be made where challenge reductions are appropriate.

Q: Has the NRC accepted LILCO's proposed response to II.K.3.16?

A: No, it has not. At the June 8,1982 SER open item review meeting, the NRC indicated that expect to complete the generic review of this issue until the end of the year.

Q: Does that complete your testimony?

A: Yes it does.

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ATTACHMENT 1 NUREG-0737 PP. II.K.3.16-1, 2 63

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li.K.~1.16 RI'OllCT10N OF CilAl.l.ENGIS AND FAlttJRr5 0F RELIEF VALVES--FFASillil'lTY SIUDY AND SYSILM M001FICAl10N Position The record of relief-valve failures to clos'e for all boiling-water reactors *

(BWRs) in the past 3 years of plant operation is approximately 30 in 73 reactor-years (0.41 failures per reactor year). This has demonsteated that the failure of a relief valve to close would be the most likely cause of a small-break loss-of-coolant acciden (LOCA). The high failure rate is the result of c high relief-valve challenge rate and a relatively high failure rate per challenge (0.16 failures per challenge). Typically, five valves are challenged in each event. This results in an equivalent failure rate per challenge of 0.03. The challenge and failure rates can be reduced in the following ways:

(1) Additional anticipatory scram on loss of feedwater, (2) Revised relief-valve actuation setpoints, (3) Increased emergency core cooling (ECC) flow, (4) Lower operating pressures, (5) Earlier initiation of ECC systems (6) Heat removal through emergency condensers, (7) Offset valve setpoints to open fewer valves per challenge, .

(8) Installation of additional relief vales with a block- or isolation-valve feature to eliminate opening of the safety / relief valves (SRVs), consis' tent with the ASME Code, (9) Increasing the high f.aam line flow setpoint for main steam line isolation valve (MSIV) closure, (10) Lowering the pressure setpoint for MSIV closure, (11) Reducing the testing frequency of the~MSIVs, (12) More-stringent valve leakage criteria, and (13) Early removal of leaking valves. _

An investigation of the feasibility and contraindications of reducing challenges to the relief valves by use of the aforementioned methods should be conducted.

Other methods should also be included in the feasibility study. Those changes which are shown to reduce relief-valve challenges without compromising the performance of the relief valves or other systems should be implemented.

, Challenges to the relief valves should be reduced substantially (by an order of magnitude).

3-156 I I . K. 3.1.6-1 -

Chances to Previous Reouirements and Guidance .

The schedule for plant modifications has been changed to allow time for staff review of evaluation and purchase of required hardware.

I C1arification .

Failure of the power-operated relief valve (PORV) to reclose during the TMI-2 accident resulted in damage to the reactor core. As a consequence, relief valves in all plants, including BWRs, are being examined with a view toward their possible role in a small-break LOCA.

The safety / relief valves (SRV) are dual-function pilot-operated relief valves that use a spring-actuated pilot for the safety function and an external air-diaphragm-actuated pilot for the relief function.

The operating history of the SRV has been poor. A new design is used in some .

plants but the operational history is too brief to evaluate the effectiveness of the new design. Another way of improving the performance of the valves is to reduce the number of challenges to the valves. This may be done by the '

methods described above or by other means. The feasibility and contraindica-tions of reducing the number of challenges to the valves by the various methods should be studied. Those changes which are shown to decrease the number of challenges without compromising the performance of the valves or other systems should be implemented.

l The failure of an SRV to reclose will be the most probable cause of a small-break LOCA. Based on the above guidance and clarification, results of a detailed evaluation should be submitted to the staff. The licensee shall document the proposed system changes for staff appt' oval before implementation. *

Acolicability I

This requirement applies to all operating BWRs and BWR operating license I

applicants.

l Imolementation l

l Results of the evaluation shall be submitted by April 1,1981 for staff review.

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.. The actual modification shall be accomplished during the next scheduled refueling l outaga following staff approval or no later than 1 year following staff approval.

Modi fication to be implemented should be documented at the time of implementation.

Type of Review A preimplementation review will be performed.

Documentation Required t

! Ily /\pri l 1, lUllt , Iicenneen mur.L bubmlL t.he rin. u i 1.t. uI t.he I gui Ib I I l Ly S Ludy for reducing SRV challenges and propose any necessary modifications for reducing SRV challenges.

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Technical Specification Changes Required' -- !

Modification may include testing frequency or leakage criteria which may

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require technical,-specification changes.

Reference NUREG-0625, Recommendations A-2.8, F-3.4

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SL_ftram 9h

4 UNITED STATES OF AMERICA '

NUCLEAR REGULATORY COMMISSION BEFORE THE ATOMIC SAFETY AND LICENSING BOARD

)

In the Matter of )

)

LONG ISLAND LIGHTING COMPANY )

) Docket No. 50-322 (OL)

(Shoreham Nuclear Power Station, )

Unit 1) )

)

CERTIFICATE OF SERVICE I hereby certify that copies of the " PREPARED DIRECT TESTI-MONY OF DALE G. BRIDENBAUGH AND GREGORY C. MINOR ON BEHALF OF SUFFOLK COUNTY REGARDING SUFFOLK COUNTY CONTENTION 28 (a) (vi)/

SOC 7A(6)," and the " PREPARED DIRECT TESTIMONY OF DALE G. BRIDEN-BAUGH ON BEHALF OF SUFFOLK COUNTY REGARDING SUFFOLK COUNTY CONTENTION 25," dated June 14, 1982, have been sent to the following by U.S. mail, first class, this 14th day of June, 1982.

Lawrence Brenner, Esq. Ralph Shapiro, Esq.

Administrative Judge Cammer and Shapiro Atomic Safety and Licensing Board 9 East 40th Street U.S. Nuclear Regulatory Commission New York, New York 10016 Washington, D.C. 20555 Howard L. Blau, Esq.

Dr. James L. Carpenter 217 Newbridge Road Administrative Judge Hicksville, New York 11801

• Atomic Safety and Licensing Board U.S. Nuclear Regulatory Commission W. Taylor Reveley III, Esq.

Washington, D.C. 20555 Hunton & Williams P.O. Box 1535 Dr. Peter A. Morris Richmond, Virginia 23212 Administrative Judge Atomic Safety and Licensing Board U.S. Nuclear Regulatory Commission Mr. Jay Dunkleberger Washington, D.C. 20555 New York State Energy Office Agency Building 2 Edward M. Barrett, Esq. Empire State Plaza General Counsel Albany, New York 12223 Long Island Lighting Company 250 Old Country Road Stephen B. Latham, Esq.

Mineola, New York 11501 Twomey, Latham & Shea Attorneys at Law Mr. Brian McCaffrey P.O. Box 198 Long Island Lighting Company 33 West Second Street 175 East Old Country Road Riverhead, New York 11901 Hicksville, New York 11801

Fr

• , o Marc W. Goldsmith Mr. Jeff Smith Energy Research Group, Inc. Shoreham Nuclear Power Station 400-1 Totten Pond Road P.O. Box 618 Waltham, Massachusetts 02154 North Country Road Wading River, New York 11792 Joel Blau, Esq.

New York Public Service Commission MHB Technical Associates The Governor Nelson A. Rockefeller 1723 Hamilton Avenue Building Suite K Empire State Plaza San Jose, California 95125 Albany, New York 12223 Hon. Peter Cohalan David H. Gilmartin, Esq. Suffolk County Executive Suffolk County Attorney County Executive / Legislative County Executive / Legislative Bldg. Building Veterans Memorial Highway Veterans Memorial Highway Hauppauge, New York 11788 Hauppauge, New York 11788 Atomic Safety and Licensing Ezra I. Bialik, Esq.

Board Panel Assistant Attorney General U.S. Nuclear Regulatory Commission Environmental Protection Bureau Washington, D.C. 20555 New York State Department of Law Docketing and Service Section 2 World Trade Center Office of the Secretary New York, New York 10047 U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Atomic Safety and Licensing l Appeal Board Bernard M. Bordenick, Esq. U.S. Nuclear Regulatory David A. Repka, Esq. Commission j U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Washington, D.C. 20555 l

1 l Matthew J. Kelly, Esq.

i Staff Counsel, New York State Public Service Commission 3 Rockefeller Plaza Albany, New York 12223

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Christooher M. McMurra KIRKPATRICK, LOCKHART,y HILL, [

CHRISTOPHER & PHILLIPS 1900 M Street, N.W., 8th Floor I Washington, D.C. 20036 June 14, 1982 l

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