ML20198D580

Summary of 981119 Meeting with Util in Rockville,Md to Discuss Proposed Changes to Design & Licensing Basis of Containment Isolation Provisions for Feedwater Sys

ML20198D580
Person / Time
Site:	Perry
Issue date:	12/15/1998
From:	Pickett D NRC (Affiliation Not Assigned)
To:	NRC (Affiliation Not Assigned)
References
NUDOCS 9812230131
Download: ML20198D580 (17)

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UNITED STATES h_ g/tg

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k % , * ,o December 15, 1998 ,

LICENSEE: Cleveland Electric illuminating Company l FACILITY: Perry Nuclear Power Plant, Unit No.1 l

SUMMARY

OF NOVEMBER 19,1998 MEETING ON FEEDWATER ISOLATION l

PROVISIONS '

On November 19,1998, NRC staff met with representatives of Cleveland Electric illuminating Company (CEI)in Rockville, Maryland. The purpose of the meeting was to discuss proposed changes to the design and licensing basis of the contair. ment isolation provisions for the feedwater system. A list of the meeting participants is included as Enclosure 1. The meeting handouts are included in Enclosure 2.

l Isolation provisions for the feedwater penetrations take credit for three isolation valves. Two piston lift check valves are located immediately inside and outside of the containment penetration. A third, motor-operated gate valve is loccted further upstream, outside of  ;

containment. The current licensing basis relies on a water seal provided by the feedw ster leakage control system (FWLCS). The FWLCS injects water between the two check i alves and also between the outside check valve and gate valve. Due to the need for operator action to initiate this system and the time to fill the piping volume between the valves, the water seal will not be provided until approximately one hour following the postulated accident. In addition, for I long-term isolation provisions for a postulated feedwater line break inside containment, reliance is placed upon the motor-operated gate valve to close.

The feedwater check valves have typically failed to pass the local leak rate tests required by 10 CFR 50, Appendix J. As a result, the licensee has expended considerable resources in terms of both dollars and man-rems to refurbish these valves during outages. The licensee's submittal of September 9,1998, proposed changes to the design and licensing basis for the isolation provisions of the feedwater system. These changes included: 1) elimination of the feedwater check valves from the USAR listing of containment isolation valves; 2) elimination of local leak rate tests for the feedwater check valves; 3) performance of periodic boroscopic examination of the feedwater check valve seats to ensure functional operability; 4) rerouting of the feedwater leakage control system to inject into the stem of the motor-operated gate valves; and 5) introducing a second electrical supply to the motor-operated gate valves. The licensee stated that these changes would represent improvements to the currently approved containment isolation provisions.

The licensee and staff have different opinions regarding the current licensing basis for the feedwater isolation provisions. As described in the licensee's submittal of September 9,1998, the licensee considers the licensing basis to only include a single barrier (i.e., the motor-

operated gate valve). This is due, in part, to the staffs agreement that check valve leakage will l

not contribute to offsite accident source; the only contnoutor to the accident source from the feedwater lines is water leakage past the gate valves. In addition, the lic'ensee interprets Supplement 7 to the Perry Safety Evaluation Report (NUREG-0887) as thd staffs conclusion that the gate valve will not fail to close; whereas, the staff considers the licensing basis to g 1 i f. b d 'g 9012230131 981215 DR ADGCK0500gO ,

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2 include the three valves discussed above along with the water seal. This difference in opinion .

was not resolved. l The staff noted that a single,100% reliable isolation barrier would be precedent setting and would conflict with the requirements of General Design Criterion 56. The staff further stated that  !

it is not their intent to assume any containment isolation barrier to have 100% reliability and thus, not be subject to a single active failure. The staff believes that the licensee's request will require exemptions from both GDC 56 and the local leak rate testing requirements of Appendix J to 10 1 CFR 50. l The staff questioned the licensee's proposal to terminate local leak rate testing of the feedwater check valves. The licensee has established a 1 gpm leakage rate limit on the feedwater check valves and, as discussed above, Pese valves typically fail their "as-found" local leak rate tests.

As-found leakage values are typically on the order of 10 gpm. The staff questioned the failure mode and whether the leakage rates would further deteriorate over time if local leak rate testing ,

was not performed. When the licensee indicated that visualinspection of the "as found"  !

condition did not identify any apparent signs of degradation, the staff questioned the value of performing boroscopic e.aminations of the check valve seats. j The staff voiced its concern about maintaining a water seal in the feedwater piping. Failure to l maintain a water seal would establish an air leakage path thus mandating pneumatic testing of the check valves. The staff questioned whether increasing the leakage limits for the check valves above 1 gpm would be beneficial. The licensee stated that the leakage control system piping is small and that flow is nearly choked. Therefore, increasing flow rates is not a practical solution. i Discussion focused on the link between containment isolation and offsite dose limits. The source of water for the feedwater leakage control system is the suppression pool which may be highly contaminated following an accident. The licensee stated that if the gate valve failed to close, check valve leakage past the gate valve could potentially result in an unacceptable offsite dose. However, since the licensee believes that the licensing basis assumes the gate valves will close, leakage rates of the check valves are not important since they don't contribute to dose. In this regard, the licensee contends that the check valves are not necessary for containment isolation.

The staff concluded that the licensee's proposal was r ot acceptable. The staff cited 1) a conflict l between a single isolation barrier and GDC 56; 2) a conflict between elimination of the local leak l- rate testing of the feedwater check valves and Appendix J to 10 CFR 50; and 3) rerouting of the i feedwater leakage control system would create an air leakage path through the check valves that would not be tested.

The staff recognized the generic problems that the BWR6/ Mark Ill owners are having with local leak rate testing of feedwater check valves. Therefore, the staff suggested the licensee i consider submitting a one-time scheduler exemption from the local leak rate testing j requirements of Appendix J for their April 1999 refueling outage. This would provide the staff L with an appropriate time frame to address the problem generically. Any exemption request l would need to ensure that the water seal was maintained, include a cost / benefit analysis, and l

l

3 12/15/98 l l be risk informed. The risk study would need to address the impact of not testing the feedwater l check valves and the probability that the gate valves would not close.

The staff stressed that any long term solution would require a second isolation barrier. The licensee stated that the next system valve upstream of the gate valve would be located outside .

i of the steam tunnel in the turbine building. Questions regarding missile protection and seismic '

class were discussed.

! in cor.clusion, both the staff and the licensee stated a need to address this issue at their next,  !

respective management level. When asked if the licensee would prefer to modify their existing submittal or receive a formal denial of the existing submittal, the licensee said they would contact us. l Original signed by:

1 Douglas V. Pickett, Senior Project Manager Project Directorate 111-2 Division of Reactor Projects Ill/IV l

Office of Nuclear Reactor Regulation l Docket No. 50-440

Enclosures:

List of Meeting Participants Meeting Handouts cc w/encls: See next page DISTRIBUTION:

Hard Coov w/encls E-mail w/Enct 1 Docket File SCollins (SJC1) 'JKudrick EAdensam PD lll-2 Reading RZimmerman EThrom PUBLIC THiltz CBerlinger.

GGrant, Rlli BBoger GHolahan Hard Coov w/ Encl 1 OGC ACRS DOCUMENT NAME: G:\ PERRY \MTG11_19. SUM l Ta receive e copy of this document, indicate in the box: *C" = Copy without enclosures *E' = Copy with enclosures "N" = No copy j

OFFICE PM:PI)LI)g? LA:PDIII-2 6T D:PDIII-2 C, .

BC:SCSB ,

NAME' DPiclTth ' EBarnhill 2 F SRichards 5/EV CBerlinger('/Jh DATE 12/9 /98 12/ 7 /98 12/rd/98 12/9 /98 bil2/ /98 0FFICIAL RECORD COPY  !

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3 12/15/98 j ' be risk informed. The risk study would need to address the impact of not testing the feedwater check valves and the probability that the gate valves would not close.

The staff stressed that any long term solution would require a second isolation barrier. The licensee stat 3d that the next system valve upstream of the gate valve would be located outside of the steam tunnel in the turbine building. Questions regarding missile protection and seismic class were discussed.

l In conclusion, both the staff and the licensee stated a need to address this issue at their next,

respective management level. When asked if the licensee would prefer to modify their existing submittal or receive a formal denial of the existing submittal, the licensee said they would contact us.

Original signed by:

Douglas V. Pickett, Senior Project Manager i Project Directorate lll-2  !

Division of Reactor Projects lil/IV Office of Nuclear Reactor Regulation Docket No. 50-440 ,

Enclosures:

List of Meeting Participants Meeting Handouts i

cc w/encis

See next page DISTRIBUTION:

= Hard Coov w/encls E-mail w/Enct 1 Docket File . SCollins (SJC1) JKudrick . EAdensam PD lll-2 Reading RZimmerman EThrom PUBLIC ' THiltz .,CBerlinger l GGrant, Rlil BBoger - GHolahan Hard Coov w/ Encl 1

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OGC ACRS

. DOCUMENT NAME: G:\ PERRY \MTG11 19. SUM Ta receive a copy of this document, indcate in 'the box: "C" = Copy without enclosures ~ "E" = Copy with enclosures "N" = No copy 0FFICE PM:RDillt2 LA:PDIII-2 7 D:PDIII-2 C BC:SCSB ,

NAME DPiclCd'th ' EBarnhill W SRichards 54V CBerlingerf '#f$

DATE 12/ 9 /98 12/ 7 /98 12/l'l/98 12/9 /98 F12/ /98 OFFICIAL RECORD COPY 9

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3 be risk informed. The risk study would need to address the impact of not testing the feedwater check valves and the probability that the gate valves would not close.

The staff stressed that any long term solution would require a second isolation barrier. The licensee stated that the next system valve upstream of the gate valve would be located outside of the steam tunnelin the turbine building. Questions regarding missile protection and seismic class were discussed.

In conclusion, both the staff and the licensee stated a need to address this issue at their next, respective management level. When asked if the licensee would prefer to modify their existing submittal or receive a formal denial of the existing submittal, the licensee said they would contact us. '

Q v PM Douglas V. Pickett, Senior Project Manager Project Directorate lll-2 Division of Reactor Projects Ill/IV  ;

Office of Nuclear Reactor Regulation Docket No. 50-440

Enclosures:

List of Meeting Participants  ;

Meeting Handouts cc w/encls: See next page b

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' C:nt:rior S rvice Company PIrry Nucl3ar Pow:r Plant, Units 1 and 2 cc:

Mary E. O'Reilly James R. Williams FirstEnergy - A290 Chief of Staff 10 Center Road Ohio Emergency Management Agency Perry, OH 44081 2855 West Dublin Granville Road Columbus, OH 43235-2206 Resident inspector's Office U.S. Nuclear Regulatory Commission Donna Owens, Director P.O. Box 331 Ohio Department of Commerce Perry, OH 44081-0331 Division of Industrial Compliance Bureau of Operations & Maintenance Regional Administrator, Region ill 6606 Tusr/ng Road U.S. Nuclear Regulatory Commission P.O. Box 4009 801 Warrenville Road Reynoldsburg, OH 43068-9009 Lisle, IL 60532-4531 Mayor, Villagd of North Perry Sue Hiatt North Perry Village Hall OCRE Interim Representative 4778 Lockwood Road 8275 Munson North Perry Village, OH 44081 Mentor, OH 44060 Radiological Health Program Henry L. Hegrat Ohio Department of Health Regulatory Affairs Manager P.O. Box 118 Cleveland Electric illuminating Co. Columbus, OH 43266-0118 Perry Nuclear Power Plant P.O. Box 97, A210 Ohio Environmental Protection Perry, OH 44081 Agency DERR-Compliance Unit Lew W. Myers ATTN: Mr. Zack A. Clayton Vice President - Nuclear, Perry P.O. Box 1049 Centerior Service Company Columbus, OH 43266-0149 P.O. Box 97, A200-Perry, OH 44081 Chairman Perry Township Board of Trustees Mayor, Village of Perry 3750 Center Road, Box 65 4203 Harper Street Perry, OH 44081 Perry, OH 44081 State of Ohio FirstEnergy Corporation Public Utilities Commission Michael Beiting East Broad Street Associate General Counsel Columbus, OH 43266-0573 76 S. Main Akron, OH 44308 William R. Kanda, Jr., Plant Manager Cleveland Electric illuminating Co.

Perry Nuclear Power Plant P.O. Box 97., SB306 Perry, OH 44081

MEETING ATTENDEES NRC AND CLEVELAND ELECTRIC ILLUMINATING COMPANY l

FEEDWATER ISOLATION PROVISIONS NOVEMBER 19,1998 i

CLEVELAND ELECTRIC ILLUMINATING CO.

Robert W. Schrauder Henry L. Hegrat Bradley S. Ferrell Cal Heintz  !

Richard Dame Thomas Shega SCIENTECH - NUS Dave Studley Nfl0 Carl Berlinger Jack Kudrick Ed Throm Stuart Richards

. Doug Pickett Lawrence Burkhart ILLINOIS POWER COMPANY Dur; Korneman Enclosure 1

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Feedwater Penetration l

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NRCMeeting November 19,1998 5

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Feedwater Penetration Improvement

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• * - . g_ g 7,-,gy e ,g - - '4 e Meeting Goal: to provide information to

! support NRC approval of the amendment

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Project Goal: to improve the overall j

performance of the Feedwater Penetrations

Reduce actual dose to plant workers .

j Improve protection of the public i

Provide a risk-informed level of protection to

achieve the above goals t

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l l Feedwater Penetration Improvement l Current Configuration:

Gate valve seats have been very leak tight - no rework 1

Offsite doses are mitigated by closure of the gate

) valves (licensing post-LOCA dose cales only consider j the gate valve leakage, not the checks) ,

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Check valve leakage criteria of < 1 gpm is required to i meet the current FWLCS design function of filling the pipe within one hour, not for dose cale reasons ,

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Workers were exposed to > 5 rem to work on the

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4 check valve seats in RFO6; plus dose from testing Page 3

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l Benefits of new design l Improves the probability of the Feedwater lines

getting a water seal within the currently licensed i

period of time after a LOCA due to relocated FWLCS Improves the probability of closure of the currently l licensed high integrity gate valves, after a LOCA/ LOOP /Div.1 failure, due to new provisions for an alternate power supply

>> Reduces the dose received by workers who have been performing maintenance and testing of the checks -

>> Proposal continues to provide protection for a postulated Feedwater Line Break Outside Containment Page 4

i Feedwater Penetration Improvement l

3 Other options considered

>> Add Soft-seats to the Check Valves, and j maintain the current licensing basis l Maintain current FWLCS injection point, and 1

increase allowable Check Valve leakage -

l Design & install a new " sister" gate valve in each line i >> Many other options were also considered

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Feedwater Penetration Improvement

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l Other Options Considered (continued) i Add Soft-seats to the Check Valves, and i maintain the current licensing basis l >> Still would need to test checks, and would need to j replace seats each refuel outage due to EQ l .

l Still would see leakage > 1 gpm (EPRI) l

>> Wouldn't have the extra recovery time for actuation of

FWLCS i

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Feedwater Penetration Improvement

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Other Options Considered (continued)

Maintain current FWLCS injection point, and l

increase allowable Check Valve leakage

! Would not be able to get enough FWLCS flow into the

pipe (would require installation of new, larger diameter ,

l Class 1 connections to pass the flow in order to fill the pipe l within an hour, which is not feasible due to the design of l the penetration and of the valves) i 4

>> Still would need to test checks i Would have potential for releasing post LOCA l -

suppression pool (FWLCS) water from containment .

! Using outside clean water source would flood containment Page 7

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! Other Options Considered (continued) l Design & install a new gate valve in each line Still would need to test checks l Would provide very little benefit to the post-LOCA l reliability of the penetration as compared to the i proposed change (proposed change will provide an -

l alternate power supply to the existing gate valves)

>> Would not factor in to the analysis of the Feedwater line l break outside containment

] >> Would be a high dose job, and extremely expensive i

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>> The cost-benefit ratio does not justify this change

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Feedwater Penetration Improvement l

FirstEnergy Docketed Letter Contents l

Provide design summary of alternate power supply Provide results of operator action review

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Provide results of th'e dose cale sensitivity analysis Provide results of a risk-informed review on the proposed License Amendment -

Provide several updated USAR pages Add page from Table 3.2-1 NOTES about the third valve with high leak tight integrity.

) Revise page describing fill time on the bonnet, and adding the word "approximately".

Editorial change to cross out words that should have been crossed out in the first submittal.

l Revise page describing "both" subsystems being interlocked, to show that only one is interlocked.

] n Add page from "Feedwater Line Break Outside Containment", describing dose calc result, to show the

impact of check valve leakage on the cale (showing it remains bounded by the Main Steam Line Break Outside Containment calc).

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