ML18106A791

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Application for Amends to Licenses DPR-70 & DPR-75,revising Acceptance Criteria for CR Emergency Air Conditioning Sys from Maintaining CR at 1/8-inch Positive Pressure W/Respect to Adjacent Areas to Following Phrase
ML18106A791
Person / Time
Site: Salem  PSEG icon.png
Issue date: 07/30/1998
From: Storz L
Public Service Enterprise Group
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML18106A792 List:
References
LCR-S97-07, LCR-S97-7, LR-N970738, NUDOCS 9808070087
Download: ML18106A791 (13)


Text

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Public Service

- Electric and Gas Company Louis F. Storz Senior Vice President - Nuclear Operations

. Public Service Electric and Gas C~[y3 (f ~g§Ef 236, Hancocks Bridge, NJ 08038 609-339-5700 LR-N970738 LCR S97-07 United States Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 REQUEST FOR CHANGE TO TECHNICAL SPECIFICATIONS CONTROL ROOM EMERGENCY AIR CONDITIONING SYSTEM SALEM GENERATING STATION NOS. 1AND2 FACILITY OPERATING LICENSES DPR-70 AND DPR-75 DOCKET NOS. 50-272 AND 50-311 Gentlemen:

In accordance with 10CFR50.90, Public Service Electric & Gas (PSE&G) Company requests a revision to the Technical Specifications (TS) for the Salem Generating Station Unit Neis. 1 and 2. In accordance with 10CFR50.91 (b)(1 ), a copy of this submittal has been sent to the State of New Jersey.

The proposed TS change contained herein represents a change to Specification 3/4.7.6, "Control Room Emergency Air Conditioning System" and the associated bases.

This change revises the acceptance criteria for the Control Room Emergency Air Conditioning System (CREACS) from maintaining the Control Room at "1/8-inch positive pressure with respect to the adjacent areas" to "1/8-inch positive pressure with respect to the all areas directly accessible (Work Control Center and Control Room Equipment Rooms) from the control room and a positive pressure with respect to all other areas adjacent to the control room."

PSE&G requests these changes in order to improve safety by eliminating breaching of plant security and fire barriers to establish a ven*t path to support single filtration train (maintenance mode) operation of the CREACS and ensuring the control room operators ability to re-align the CREACS to single train operation within the four hour action time. The current practice of establishing a vent path to the relay room during single train operation of CREACS to maintain the 1/8-inch differential pressure to this room is an additional distraction to the control room operators for the alignment of CREACS to single train operation. Maintaining a positive pressure between the control room and the relay room will ensure that leakage to the control room is maintained in accordance with the assumptions used in the dose calculations since this room is not in 1 -9808070097 99 073~0:------

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aut so 199a Document Control Desk LR-N970738 direct communication with the control room envelope. Eliminating the need to establish the vent path to the relay room will allow the control room operators to maintain their focus on the safe operation of the plant while ensuring that CREACS can be aligned to single train operation within the four-hour action time required by the TS.

The proposed changes have been evaluated in accordance with 10CFR50.91(a)(1),

using the criteria in 10CFR50.92(c) and PSE&G has concluded that this request involves no significant hazards considerations.

The basis for the requested change is provided in Attachment 1. A 10CFRS0.92 evaluation with a determination of no significant hazards consideration is provided in . The marked up TS pages affected by the proposed changes are provided in Attachment 3.

Upon NRC approval of this proposed change, PSE&G requests that the amendment be made effective on the date of issuance, but allow an implementation period of sixty days to provide sufficient time for associated administrative activities.

Also, in regard to the NRC safety evaluation report (SER) for TS Amendments 190 and 173 for Unit 1 and Unit 2 respectively, the NRC staff indicated that they performed an evaluation of the Fuel Handling Accident (FHA) inside the containment for Salem. As stated in the SER, the NRC staff assumed that all airborne activity reaching the containment atmosphere is exhausted to the environment within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. The NRC staff used the NRC's ACTICODE to compute the offsite doses and determined that the computed offsite doses were within the acceptance criteria given in Standard Review Plant (SRP) Section 15.7.4. Also the NRC determined that the control room operator doses were within the acceptance criteria given in 10CFRSO Appendix A General Design Criteria (GDC) 19.

As stated in the NRC's SER for TS Amendments 190 and 173, PSE&G submitted an analysis for a postulated FHA in the fuel handling building. PSE&G has subsequently performed an evaluation of the FHA inside the containment using the TACTS computer code for offsite dose releases and the CONHAB computer code for control room doses.

Both computer codes are part of the HABIT computer code package. The resulting offsite doses are within the acceptance criteria of SRP 15.7.4 and the control room doses are within the acceptance criteria of GDC-19. The control room dose results of the FHA accident inside containment are bounded by the results obtained for the Loss-

  • of-Coolant Accident which were previously submitted to and reviewed by the NRC during approval of TS Amendments 190 and 173.

95-4933

~UL3 O 1998 I 41,t Document Gontrol Desk LR-N970738 PSE&G would like to extend an offer to meet with the NRC Staff to discuss any questions concerning the above change to the TS and provide any additional information necessary to assist the NRC Staff in their review of the change. Should you have any questions please do not hesitate to contact us.

Sincerely, Affidavit Attachments (3)

C Mr. H. J. Miller, Administrator - Region I U. S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Mr. P. Milano, Licensing Project Manager - Salem U. S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Mail Stop 14E21 Rockville, MD 20852 Mr. S. Morris (X24)

USNRC Senior Resident Inspector - Salem Mr. K. Tosch, Manager IV Bureau of Nuclear Engineering 33 Arctic Parkway P.O.Box415 Trenton, NJ 08625 95-4933

Document Control Desk

  • ~UL'$ O 1998 LR-N.970738 BJT BC Senior Vice President - Nuclear Engineering (N19)

General Manager - Salem Operations (SOS)

Director - QA/Nuc. Trng/EP (X01)

Manager - Salem Operations (S01)

Manager - System Engineering - Salem (S02)

Program Manager - Nuclear Review Board (N38)

Salem Licensing Manager (N09)

J.J. Keenan, Esq.

Records Management (N21)

Microfilm Copy Files Nos. 1.2.1 (Salem), 2.3 (LCR S97-07)

Document Control Desk LR-N970738 I. I I BJT BC Senior Vice President - Nuclear Engineering (N19)

General Manager - Salem Operations (S05)

Director - QA/Nuc. Trng/EP (X01)

Manager - Salem Operations (S01)

Manager - System Engineering - Salem (S02)

Program Manager - Nuclear Review Board (N38)

Salem Licensing Manager (N09)

J.J. Keenan, Esq.

Records Management (N21)

Microfilm Copy Files Nos. 1.2.1 (Salem), 2.3 (LCR S97-07)

- l REF: LR-N970738

LCR S97-07 STATE OF NEW JERSEY)

) SS.

COUNTY OF SALEM )

L. F. Storz, being duly sworn according to law deposes and says:

I am Senior Vice President - Nuclear Operations of Public Service Electric and Gas Company, and as such, I find the matters set forth in the above referenced letter, concerning Salem Generating Station, Units 1 and 2, are true to the best of my knowledge, information and belief.

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Subscribed and Sworn to before me this .,Z, J'f:4 ~'.ci"1Y of 1998 Notary Public of New Jersey Notary Public af My Commission~

New......,

DELORIS D. HADDEN My Commission expire~ on _ _ _ _ _03-29-2000

Document Control Des'9 . .N970738 LCR S97-07 SALEM GENERATING STATION UNIT NOS. 1 AND 2 FACILITY OPERATING LICENSES DPR-70 AND DPR-75 DOCKET NOS. 50-272 AND 50-311

  • CHANGE TO TECHNICAL SPECIFICATIONS CONTROL ROOM EMERGENCY AIR CONDITIONING SYSTEM BASIS FOR REQUESTED CHANGE REQUESTED CHANGE AND PURPOSE The proposed change to Technical Specification (TS) 3/4.7.6, "Control Room Emergency Air Conditioning System" and the associated bases revise the acceptance criteria for pressurization of the Control Room Envelope (CRE) following a radiological release.

Several system modifications were made during the previous extended outage for Salem Units 1 and 2. These modifications combined the two separate control rooms into a single control room envelope and upgraded the Control Room Emergency Air Conditioning System (CREACS) to reduce the systems vulnerability to single failures.

The upgrade to the CREACS included the ability to automatically select a favorable outside CREACS air intake under accident conditions.

The current Technical Specifications require the Control Room Envelope (CRE) to be maintained at a positive pressure of 1/8-inch water gauge (W.G.) with respect to all adjacent areas during applicable accident conditions. Testing has demonstrated, that in order to meet the pressurization requirements in the Maintenance Mode of operation (single filtration train alignment), operator action beyond normal system realignment is required. These actions include opening doors in the relay room and electrical penetration areas, posting of fire watches and establishing compensatory security measures. These actions are required due to an increase in static pressure in the relay rooms as a result of:

  • the reduced CREACS flow rate achieved with a single supply fan (one train of CREACS operating),
  • the increased Control Area Air Conditioning System (CAACS) recirculation flow due to the isolation of CAACS to the CRE, and
  • the assumed loss of equipment due to an electrical bus failure.

The increase in static pressure in the relay room causes the differential pressure between the CRE and the relay room to decrease below +1/8-inch W.G. In order to alleviate the pressure increase in the relay room to maintain the 1/8-inch W.G.

differential pressure between the CRE and the relay room, the doors mentioned above 1

Document Control Desk9 .N970738 LCR S97-07 are-opened during single filtration train alignment to establish a pressure relief (vent) path for the relay room.

The proposed change to the Technical Specification revises the CRE pressurization acceptance criteria to reflect a requirement to maintain an 1/8-inch W.G. positive differential pressure with respect to all areas directly accessible (Work Control Center and Control Room Equipment Rooms) from the control room and a positive pressure with respect to all other areas adjacent to the control room. The purpose of this change improves the safety of the plant by:

(1) eliminating the breaching of plant security and fire barriers to support the maintenance mode of operation (2) ensuring the control room operators ability to re-align the CREACS to single train operation within the four hour action time required by TS while maintaining their focus on overall plant safety.

BACKGROUND As described in Section 9.4.1 of the Salem Updated Final Safety Analysis Report (UFSAR), the Control Area Air Conditioning System (CAACS) is designed to maintain room temperatures within limits required for operation, maintenance and testing of plant controls and uninterrupted safe occupancy of the CRE during post-accident conditions.

The system operates during normal or emergency conditions as required. A portion of the CAACS, designated the CREACS, operates during emergency conditions to satisfy these functional requirements for Control Room Habitability. The principle function of the CREACS is to ensure the habitability of the control room during a loss of coolant accident (LOCA) or other radiological conditions which could result in exposures to plant operators exceeding GDC 19 limits if no protective features were actuated.

The recent modifications to the CRE for Salem Units 1 and 2 combined the two separate control rooms into a single control room envelope. The CREACS was also modified to actuate to pressurize the CRE during radiological accidents. Dose calculations performed to support the modification of the CRE have shown that the CREACS can maintain doses below the limits of GDC 19 while taking into account plausible failure scenarios. These dose calculations were reviewed by the NRC during the approval of Amendments 190 and 173 to the Unit 1 and Unit 2 Technical Specifications (TS), respectively.

JUSTIFICATION OF REQUESTED CHANGES The functional design of the CREACS is controlled by the requirements set forth in NRC General Design Criterion (GDC) 19. Therein it is specified that control room doses shall 2

Document Control Des'9 .N970738 LCR S97-07 be limited*fo 5 rem whole body and 30 rem thyroid dose for the duration of the accident.

The CREACS is capable of meeting this requirement in all modes of operation as defined in the current design and licensing basis. This capability is assured through automatic actuation of the system during normal plant operation (i.e., two CREACS trains available) and after manual realignment of the system to the maintenance mode of operation (i.e., a single CREACS train available).

As part of the overall redesign of the CREACS, PSE&G adopted a more restrictive CRE pressurization requirement. It was felt that the integrity of the CRE was such that this requirement could be satisfied with minor modifications to the existing compliment of fans, ductwork and dampers. Subsequent post-installation testing identified that interfacing ventilation systems had a greater influence on CRE pressurization than originally anticipated. After additional sealing of the CRE boundary, testing demonstrated that the CRE pressurization requirements could be satisfied, with limited margins, for all normal alignments with simulated single failures (i.e., Loss of Vital Bus).

However, testing in the maintenance mode alignment (single filtration train) indicated that venting of adjacent areas was required when failures were simulated in order to satisfy the CRE pressurization requirements.

As previously stated, PSE&G has expanded the maintenance mode alignment procedure to include opening of fire and security doors in the adjacent relay and switchgear areas, and posting of the requisite compensatory fire watches and security guards. While these compensatory measures are acceptable from a safety perspective, they remove the first barrier of the defense-in-depth design for these areas. The opening of the fire and security doors also provides a challenge to the

  • operators to align the CREACS for single filtration train operation within four hours as required by TS Action Statement (TSAS) 3.7.6.1.a (Unit 1) and 3.7.6.a (Unit 2) when the TSAS is entered as a result of equipment failures that render one train of CREACS inoperable.

Given the above, PSE&G is proposing to revise the CRE pressurization acceptance criteria to reflect a requirement to maintain a 1/8-inch W.G. positive differential pressure with respect to all areas directly accessible (Work Control Center and Control Room Equipment Rooms) from the control room and a positive pressure with respect all other areas adjacent to the control room. This pressure requirement will ensure that the CRE is maintained as a pressurized space even during periods of ingress and egress from the CRE, thereby minimizing unfiltered infiltration to the control room and satisfying the limits of GDC 19.

The current practice of establishing a vent path to the relay room during single train operation of CREACS to maintain the 118-inch differential pressure to this room is an additional distraction to the control room operators for the alignment of CREACS to 3

Document Control Desa .N970738 Attachment 1 LCR S97-07 singl'e traih *operation. Maintaining a positive pressure between the control room and the relay room will ensure that leakage to the control room is in accordance with the assumptions used in the dose calculations since this room is not in direct communication with the control room envelope. Eliminating the need to establish the vent path to the relay room will also allow the control room operators to maintain their focus on the safe operation of the plant by allowing the control room operators to concentrate on addressing the equipment malfunctions causing the CREACS system to be aligned to single train operation.

RADIOLOGICAL CONSEQUENCES The radiological dose assessment was submitted and reviewed by the NRG during Amendments 190 (Unit 1) and 173 (Unit 2). The worst case control room dose analyses were based on the modified control room envelope arrangement, the upgraded CREACS design, automatic selective air intake logic and HEPA and charcoal filter efficiency of 95 percent. The calculations utilize the automatic selection capability of the CREACS to select the less contaminated control room intake while assuming that only one of the CREACS filtration trains is operating. These calculations demonstrate that, for the worst case accident, the doses in the CRE are maintained below GDC 19 limits. The dose calculations also demonstrate that during plausible single failures (e.g., failure of a radiation monitor CPU causing both intakes to open, or only the accident unit intake opening) with both trains of CREACS operating, dose rates are bounded by the dose analysis mentioned above. The proposed change to the acceptance criteria to maintain a 1/8-inch W.G. positive pressure in the CRE with respect to all areas directly accessible from the control room and a positive pressure to all other areas adjacent to the CRE does not alter the assumptions used in the radiological dose assessment.

CONCLUSIONS Revising the acceptance criteria of the CREACS to ensure that the CRE is maintained at a 1/8-inch W.G. positive pressure in the control room with respect to all areas directly accessible (Work Control Center and Control Room Equipment Rooms) from the control room and a positive pressure to all other areas adjacent to the control room does not

  • change the assumptions used in radiological assessments reviewed by the NRG under Amendments 190 (Unit 1) and 173 (Unit 2). These radiological assessments demonstrate that the CREACS can maintain the CRE dose within the requirements of GDC 19 and provide the necessary protection to the operators to support the operation of Salem Units 1 and 2.

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Document Control Des~ .N970738 Attachment 2 LCR S97-07 SALEM GENERATING STATION UNIT NOS.1AND2 FACILITY OPERA TING LICENSES DPR-70 AND DPR-75 DOCKET NOS. 50-272 AND 50-311 CHANGE TO TECHNICAL SPECIFICATIONS CONTROL ROOM EMERGENCY AIR CONDITIONING SYSTEM 10CFR50.92 EVALUATION Public Service Electric & Gas (PSE&G) has concluded that the proposed changes to the Salem Generating Station Unit Nos. 1 and 2 Technical Specifications (TS) do not involve a significant hazards consideration. In support of this determination, an evaluation of each of the three standards set forth in 10CFR50.92 is provided below.

REQUESTED CHANGE The proposed TS change revises the acceptance criteria of the Control Room Emergency Air Conditioning System (CREACS) to ensure that the control room

  • envelope (CRE) is maintained at a 1/8-inch W.G. positive pressure in the control room

. with respect to all areas directly accessible (Work Control Center and Control Room Equipment Rooms) from the control room and a positive pressure to all other areas adjacent to the control room .

. BASIS

1. The proposed change does not involve a significant increase in the probability or .

consequences of an accident previously evaluated.

CREACS ensures adequate protection after an accident and is not an accident initiator. The change to the acceptance criteria for CREACS does not affect the probability of an accident.

Revising the acceptance criteria for the CREACS from a '1/8-inch W.G. positive pressure in the control room with respect to the adjacent areas' to 'a 1/8-inch W.G. positive pressure in the control room with respect to all areas directly accessible (Work Control Center and Control Room Equipment Rooms) from the control room and a positive pressure to all other. areas adjacent to the control room' does not alter the assumptions in the radiological dose assessment provided to the NRG and approved under Amendments 190 (Unit 1) and 173 (Unit 2). Therefore the conclusions of the radiological dose assessment reviewed and approved by the NRG under the above Amendments remain 1

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Document Control Des. 9N970738 LCR S97-07 uncnanged. The radiological dose assessment provided under Amendments 190 and 173 demonstrates that operation of the CREACS in the pressurized mode at the initiation of an accident will ensure that the requirements of General Design Criterion (GDC) 19 will be met.

Therefore, the proposed TS change does not involve a significant increase in the probability or consequences of an accident previously evaluated.

2. The proposed change does not create the possibility of a new or different kind of accident from any accident previously evaluated.

Since the CREACS is an accident mitigation system that does not communicate with the Reactor Coolant Pressure boundary or interface with Emergency Core Cooling Systems (ECCS), the proposed change to the acceptance criteria for CREACS pressurization cannot result in new accident scenarios. The function of the CREACS system is to maintain the habitability of the CRE following an accident.

Therefore, the proposed TS change does not create the possibility of a new or different kind of accident from any accident previously evaluated.

3. The proposed change does not involve a significant reduction in a margin of safety.

The CREACS ensures that (1) the ambient air temperature does not exceed the allowable temperature for continuous duty rating for equipment and instrumentation cooled by the CREACS and (2) the Control Room will remain habitable for operations personnel during and following all credible radiological accident conditions. Revising the acceptance criteria to maintaining the control room at a 1/8-inch W.G. positive pressure in the control room with respect to all areas directly accessible (Work Control Center and Control Room Equipment Rooms) from the control room and a positive pressure to all other areas adjacent to the control room does not alter the assumptions used in the radiological dose assessment nor revise the conclusions of the dose assessment which was reviewed under Amendments 190 and 173. Since the assumptions and conclusions of the dose assessment remain unchanged, the CREACS continues to ensure that the requirements of GDC 19 continue to be met, and there is no reduction in the safety provided to the control room operators.

Therefore, the proposed change to the TS does not involve a reduction in the margin of safety.

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Document Control Des. 9N970738 LCR S97-07 CONCLUSION Based on the above, PSE&G has determined that the proposed change does not involve a significant hazards consideration.

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