ML18094A356
| ML18094A356 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 04/17/1989 |
| From: | Labruna S Public Service Enterprise Group |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NLR-N89076, TAC-68596, TAC-68597, NUDOCS 8904260405 | |
| Download: ML18094A356 (9) | |
Text
Public Service Electric and Gas Company Stanley LaBruna Public Service Electric and Gas Company P.O. Box 236, Hancocks Bridge, NJ 08038 609-339-4800 Vice President - Nuclear Operations APR 1 'l ~
NLR-N89076 U. s. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 Gentlemen; STATION BLACKOUT COPING ANALYSIS SALEM GENERATING STATION UNIT NOS. 1 AND 2 DOCKET NOS. 50-272 AND 50-311 Public Service Electric and Gas (PSE&G) hereby submits Attachments 1 and 2 to this letter in response to the requirements of 10 CFR 50.63 (NRC Reference TAC 68596 and 68597). provides the results of the coping category determination and coping analysis study performed for Salem Generating Station Units 1 and 2. provides a detailed schedule for the completion of procedural changes identified to date.
Additionally, PSE&G will complete the modifications identified in Attachment 1 within 2 years of receipt of the notification identified in 50.63(c)(3).
If there are any questions regarding the attached, please feel free to contact me.
Sincerely, Attachments
Document Control Desk NLR-N89076 C
Mr. J. C. Stone Licensing Project Manager Ms. K. Halvey Gibson Senior Resident Inspector 2
Mr. W. T. Russell, Administrator Region I Mr. K. Tosch, Chief New Jersey Department of Environmental Protection Division of Environmental Quality Bureau of Nuclear Engineering CN 415 Trenton, NJ 08625 APR 17 1909
e ATTACHMENT 1 TO NLR-N89076 Public Service Electric & Gas Company Salem Generating Station - Units 1 & 2 Response to Station Blackout Rule AC INDEPENDENT COPING On July 21, 1988, the Nuclear Regulatory Commission (NRC) amended its regulations in 10 C.F.R., Part 50.
A new section, 50.63, was added which required that each light-water-cooled nuclear power plant be.able to withstand and recover from a station blackout (SBO) of a specified duration.* Utilities are expected to have the baseline assumption, analyses, and related information used in their coping evaluation available for NRC review.
It also identifies the factors that must be considered in specifying the station blackout duration.. Section 50.63 requires that,' for the station blackout duration, the plant be capable of maintaining core cooling and appropriate containment integrity.
Section 50.63 further requires that each licensee submit the following information:
- 1.
A proposed station blackout duration including a justification for the selection based on the redundancy and reliability of the onsite emergency AC power sources, the expected frequency of loss of offsite poweri and the probable time needed to restore offsite power;
- 2.
A description of the procedures that will be implemented for station blackout events for the duration (as determined in 1 above) and for the recovery therefrom; and
- 3.
A list and proposed schedule for any needed modifications to equipment and associated procedures necessary for the specified SBO duration.
The NRC has issued Regulatory Guide 1.155 "St~tion Blackout" which describes a means acceptable to the NRC Staff for meeting the requirements of 10 C.F.R. 50.63.
Regulatory Guide (RG) 1.155 states that the NRC Staff has determined that NUMARC 87~00 "Guidelines and Technical Bases for NUMARC Initiatives Addressing Station Blackout At Light Water Reactors" also provides guidance that is in large part identical to the RG 1.155 guidance and is acceptable to the NRC Staff for.meeting these requirements.
- Table 1 to RG 1.155 provides a cross-reference between RG 1.155 and NUMARC 87-00 and notes where the RG takes precedence.
Page 1 of 6
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e ATTACHMENT 1 TO NLR-N89076 Public Service Electric & Gas Company (PSE&G) has evaluated the Salem Station -
Units 1 & 2 against the requirements of the SBO rule using guidance from NUMARC 87-00 except where RG 1.155 takes precedence.
The results of this evaluation are detailed below.
(Applicable NUMARC 87-00 sections are shown in parenthesis.)
A.
PROPOSED STATION BLACKOUT DURATION NUMARC 87-00, Section 3 was used to determine a proposed SBO duration of four hours.
No modifications were required to attain this proposed coping duration category.
- However, site specific weather data was utilized to achieve this coping category (Ref. NUS-5175 "Estimated Frequency of Loss of Off-site Power Due to Extremely Severe Weather (ESW) and Severe Weather (SW) for Salem and Hope Creek Generating Stations" -
March 1989).
The following plant factors were identified in determining the proposed station blackout duration:
- 1.
AC Power Design Characteristic Group is Pl based on:
- a.
Expected frequency of grid-related Loss of Offsite Power Events (LOOPs) does not exceed once per 20 years (Section 3.2.1, Part lA, p. 3-3);
- b.
Estimated frequency of LOOPs due to extremely severe weather places the plant in ESW Group 2 (Section 3.2.1, Part lB, p. 3-4);
- c.
Estimated frequency of LOOPs due to severe weather places the plant in SW Group 2 (Section 3.2.1, Part lC, p. 3-7);
- d.
The offsite power system is in the Il/2 Group (Section 3.2.1, Part lD, p. 3-10);
- 2.
The emergency AC power configuration group is D based on:
(Section 3.2.2, Part 2C, p. 3-13)
- a.
There are three emergency AC power supplies normally available (dedicated) to the blacked-out unit's safe shutdown equipment that are not credited as alternate AC power sources (Section 3.2.2, Part 2A, p. 3-15);
- b.
Two of the three emergency AC power supplies at each unit are necessary to. operate safe shutdown equipment following a loss of offsite power power (Section 3.2.2, Part 2B, p. 3-15).
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e ATTACHMENT 1 TO NLR-N89076
- 3.
A target EDG reliability of 0.975 was selected based on having a nuclear unit average EDG reliability for the last 100 demands greater than 0.95, consistent with NUMARC 87-00, Section 3.2.4.
B.
PROCEDURE DESCRIPTION Plant procedures have been reviewed and changes necessary to meet NUMARC 87-00, will be implemented in the following areas:
- 1.
Station Blackout response per NUMARC 87-00, Section 4.2.1 (Reference Pr6cedure; 1{2}-EOP-LOPA-1, Loss of Ali AC Power).
These procedures will be revised to address the following items; 1) opening of control room doors, 2) stripping of DC loads to assure battery capability, and 3) establishment of_ supplemental cooling to the steam driven Auxiliary Feedwater Pump room. A detailed schedule for procedure revisions is provided in Attachment 2.
- 2.
AC power restoration per NUMARC 87-00, Section 4.2.2 (Reference Procedur~s; Electric System Restoration Plan/June 1986, and 1(2)-EOP-LOPA-1).
_The Electric System Restoration Plan will be revised to establish a clear priority for repair activittes and resource allocation necessary to support 500 kV power restoration to Artificial Isl.and. - 1 (2)-EOP-LOPA-1 will b~ revised to identify necess~ry operator actioni for stabilizing plant conditions upon recovery of AC power in support of proceeding to cold shutdown.
A detailed schedule for procedure revisions is provided in.
- 3.
Severe Weather per NUMARC 87-00, Section 4.2.3, procedure AOP-WIND-1, Salem Unit 1 and 2, Flooding and/or High Wind Condition.
These procedures have been reviewed and de~ermined to be acceptable in their present form.
The Salem Generating Station coping category determination has not taken credit for pl~nt shutdown prior to the onset of hurricane winds.
Additionally, PSE&G takes exception to the NUMARC 87-00 recommendation for EDG start and load test in response to the declaration of a hurricane warning.
It is our position that this is an unjustifiable challenge to our first line of defense for loss of offsite power events.
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ATTACHMENT 1 TO NLR-N89076 C.
PROPOSED MODIFICATIONS AND SCHEDULE The ability of Salem Station - Units 1 & 2 to cope with a station blackout for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> in accordance with NUMARC 87-00, Section 3.2.5 and as determined in Section "A" above; was assessed using NUMARC 87-00,. Section 7 with the following results:
- 1.
Condensate Inventory for Decay Heat Removal (Section 7.2.1)
- 2.
The minimum permissible Auxiliary Feed Water Storage Tank (AFWST) level per technical specifications provides 197,000 gallons of usable water.
It has been determined from a plant specific computer analysis that this amount of water exceeds the required quantity for coping with*a 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> station blackout.
Class lE Battery(ies) Capacity (Section 7.2.2)
Battery capacity calculations have been performed, pursuant to NUMARC 87-00, Section 7.2.2, that verify the following:
- a.
The Class lE 28 Vdc batteries have sufficient capacity to meet station blackout loads for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.
- b.
The Class lE 125 Vdc batteries have sufficient capacity to meet station blackout loads for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> assuming loads not needed to cope with a station blackout are stripped.
Modifications to 1(2)-EOP-LOPA-1 to reflect DC load stripping are discussed under B.l of this response.
- 3.
Compressed Air (Section 7.2.3)
Air-operated valves relied upon to cope with a station blackout for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> have sufficient backup sources independent of the preferred and blacked out unit's Class lE power supply.
- 4.
Effects of Loss of Ventilation (Section 7.2.4)
- a.
The calculated steady-state ambient air temperature for the steam driven AFW pump room (the dominant area of concern for a PWR) during a station blackout induced loss of ventilation is 135°F with the room door open.
However, the rate of heat-up requires opening the room door within a very short time frame and is determined to not be a reasonable mitigating action.
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ATTACHMENT 1 TO NLR-N89076 PSE&G is evaluating potential modifications which would provide the necessary supplemental cooling in this room.
Additionally, modifications will be accomplished to provide indication of steam driven AFW pump bearing temperature.
- b.
The assumption in NUMARC 87-00, Section 2.7.1 that the control room will not exceed 120°F during a station blackout event has been assessed.
The control room at Salem Units 1 & 2 does not exceed 120 °F with the doors open during a Station Blackout.
The procedure changes to require opening of doors are addressed under item B.1 of this response.
Reasonable assurance of the operability of station blackout response equipment in the above dominant areas of concern has been assessed using Appendix F to NUMARC 87-00 and/or the Topical Report.
Plant modifications and/or procedure changes are required to provide reasonable assurance.for equipment operability have been addressed in items B.1 and C.4.a of this response.
- 5.
Containment Isolation (Section 7.2.5)
The plant list of containment isolation valves has been
- .reviewed and it has been verified that valves which must be capable of being closed or that must be operated (cycled) under station blackout conditions can be manually positioned (with local mechanical indication) ind~pendent of the preferred and blacked-out unit's Class lE power supplies.
No plant modifications ahd/or associated procedure changes were determined to be required to ensure that appropriate containmerit integrity can be provided under SBO conditions.
Those cont~inment isolation Valyes not required to operate in response to the event are assumed to be in their normal position at the onset of the event or to have failed to the design basis position upon loss of power.
Position verification for these valves is not
_required.
- 6.
Reactor Coolant Inventory (Section 2.5)
Th~ ability to maintain adequate reactor coolant system inventory to ensure that the core is cooled has been assessed for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.
A plant-specific analysis was used for this assessment.
The expected rates of reactor coolant inventory loss under SBO conditions do not result in core uncovery. Therefore, makeup systems in addition to those currently available under SBO Page 5 of 6
e ATTACHMENT 1 TO NLR-N89076 conditions are not required to maintain core cooling under natural circulation.
The modifications identified in Part C above will be completed within two years after the notification provided by the Director, Office of Nuclear Reactor Regulation in accordance with 10 C.F.R. 50.63(c) (3).
Revisions to procedures identified in Part B above will pe completed in accordance with the schedule provided in to this response.
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Procedure Number 1(2)-EOP-LOPA-1 (Un-numbered)
ATTACHMENT 2 TO NLR-N89076 Title Loss of All AC Power Electric System Restoration Plan Page 1 of 1 Schedule Procedure Revisions January 1990 Operator Training April 1990 Simulator Upgrade (If Necessary)
October 1990 October 1989 l