ML20072F406

Provides Request for NRC Enforcement Discretion Re Requirements of LCO 3.6.2.2 Action Statement a

ML20072F406
Person / Time
Site:	Beaver Valley
Issue date:	08/15/1994
From:	Noonan T DUQUESNE LIGHT CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20072F401	List: ML20072F398 ML20072F403 ML20072F406
References
NUDOCS 9408230325
Download: ML20072F406 (5)

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T4(5 re:epnene (4 m meco Nuclev Group NcN<)oiare eA isa77.oca4 August 15, 1994 U. S. Nuclear Regulatory Commission

. Attn: Document Control Desk Washington, DC 20555

Subject:

Beaver Valley Power Station, Unit No. 2 Docket No. 50-412, License No. NPP-73 Request for Enforcement Discretion This letter provides our request for NRC enforcement discretion regarding the requirements of Limiting Condition For Operation (LCO) 3.6.2.2 Action Statement "a." Details supporting this request are located in the enclosure which has been prepared in accordance with the NRC's policy statement as documented in the Federal Register dated March 17, 1993 (58 FR 14308). This request has been reviewed by our Onsite Safety Committee (OSC) and is determined to be safe.

Enforcement discretion is requested for the time period necessary to process and receive NRC approval for a change to the technical specifications reflecting the revised flow requirements associated with the "A" recirculation spray pump.

Questions regarding this submittal may be directed to N. R. Tonet, Manager, Nuclear Safety Department, at (412) 393-5210.

Sincerely, T. P. Noonan Division Vice President Nuclear Operations 1

Attachment l cc: Mr. L. W. Rossbach, Sr. Resident Inspector l Mr. T. T. Martin, NRC Region I Administrator Mr. G. E. Edison, Sr. Project Manager 1

ee;7 The Nuclear Professionals 9408230325 940817 PDR ADOCK 05000412 P PDR

Evaluation Supporting Enforcement Discretion Beaver Valley Power Station - Unit No. 2 Docket No. 50-412, License No. NPF-73 Recirculation Spray Specification 3.6.2.2

1. The technical specification or other license conditions that will be violated.

The Limiting Condition for operation (LCO) 3.6.2.2 Action Statement "a" requires that with one containment recirculation spray subsystem inoperable, the subsystem must be restored to operable status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or the plant must be in Hot Standby within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. The "A" recirculation spray subsystem was declared inoperable at 3:15 P.M. on August 12, 1994, because it was determined that the pump could not supply the technical specification required flow. Surveillance Requirement 4.6.2.2.d requires that the pump develop a differential pressure of equal to or greater than 112 psid at a flow of equal to or greater than 3500 gpm.

2. The circumstances surrounding the situation, including the need for prompt action.

In accordance with the technical specification action statements, the plant would be required to shutdown to Hot Standby conditions within 78 hours9.027778e-4 days <br />0.0217 hours <br />1.289683e-4 weeks <br />2.9679e-5 months <br /> of declaring the "A" recirculation spray subsystem inoperable. Permission is requested to continue plant operation with a reduced recirculation spray flow and not initiate a shutdown of Beaver Valley Unit No. 2 at 3:15 P.M., August 15, 1994, and be in Mode 3 by 9:15 P.M. the same day.

I During the process of evaluating the past recirculation spray l system pump performance, it was observed that the "A" recirculation spray system pump flow element 2RSS*FE-157A certified calibration report predicts a flow of 3850 gpm at 100 inches of water column (wc) differential while the flow transmitter 2RSS*FT-157A was calibrated to indicate 4000 gpm at 100 inches wc. This calibration mismatch is unaccounted for in the test loop analysis. The result is that flows recorded during surveillance testing would be non-conservatively measured. Corrections of the calibration mismatch has resulted in a revised predicted flow of approximately 3388 gpm at 112 psid which is less than the technical specification required flow.

Beaver Valley Power Station Unit No. 2 Enforcement Discretion Recirculation Spray Specification 3.6.2.2 Page 2

3. The safety basis for the request that enforcement discretion be exercised, including an evaluation of the safety significance and potential consequences of the proposed course of action.

The function of the recirculation spray system pumps is to take suction on the containment sump and discharge to the spray rings located in the containment dome during a Design Basis Accident.

This provides cooling inside containment and will maintain a subatmospheric containment for the duration of the accident. The containment is initially brought to a subatmospheric condition utilizing the quench spray system and the recirculation spray system following transfer to recirculation; the recirculation spray system will maintain the containment subatmospheric.

A reanalysis of the recirculation spray system has been conducted assuming a lower river water temperature of 87'F versus the Cesign Basis Accident value of 89 F. The results demonstrate that the recirculation spray system can adequately perform its safety function consistent with Design Basis Accident requirements (i.e., the containment is returned to subatmospheric conditions and remains subatmospheric).

As a result, it is concluded that there is a low safety significance with no change to the potential consequences of a Design Basis Accident resulting from this proposed course of action.

4. Any proposed compensatory measure (s).

The river water temperature is currently verified acceptable as less than 87*F per Log L-5 Item #89. Technical Specification 4.7.5.1 requires verifying an average river water temperature of 89"F once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. The L-5 log will be revised to include a note that would require the "A" recirculation spray system pump to be declared inoperable should the river water temperature exceed 87 F.

5. The justification for the duration of the noncompliance.

A change to the technical specification will be required. It is requested that enforcement discretion be exercised for the period I of time required to process and receive NRC approval of a proposed change to the technical specifications to revise the "A" l pump flow to 3275 gpm at 110 psid. A request for an emergency j technical specification amendment will be submitted by August 26, l

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Beaver Valley Power Station Unit No. 2 Enforcement Discretion Recirculation Spray Specification 3.6.2.2 Page 3

6. The basis for the licensee's conclusion that the noncompliance will not be of potential detriment to the public health and safety and that a significant safety hazard is not involved.

The Duquesne Light Company has determined that there is no significant safety impact associated with this request for enforcement discretion regarding Surveillance Requirement 4.6.2.2.d as it applies to the requirements of LCO 3.6.2.2 action statement "a." It has been determined through analysis that the actual system flows exceed revised required flows when actual and expected conditions regarding river water temperatures are considered.

The ability of the recirculation spray system to assist in achieving and maintaining the containment subatmospheric with the river water temperature less than 87'F is consistent with containment design basis accident assumptions and remains unchanged. There are no changes to the assumptions related to calculating offsite dose, therefore, there is no potential detriment to public health and safety and no significant safety hazard exists.

7. The basis for the licensee's conclusion that the noncompliance will not involve adverse consequences to the environment.

Accident analysis consequences remain unchanged as a result of this request. The containment will return to a subatmospheric condition within one hour following a Design Basis Accident and remain subatmospheric for the duration of the accident.

Additionally, there are no releases to the environment which are associated with approval of this request for enforcement discretion. Therefore, the requested enforcement discretion involves no adverse environmental consequences.

8. A statement that the request has been approved by the facility organization that normally reviews safety issues (Plant Onsite-Review Committee, or its equivalent).

This request has been reviewed and found acceptable by the Onsite Safety Committee.

i A

7-Beaver Valley Power Station Unit No. 2 Enforcem.ent Discretion Recirculation Spray Specification 3.6.2.2 Page 4

9. Any other information the NRC staff dooms necessary before making a decision to exercise enforcement dismretion.

The following items were discussed with the NRC during a conference call on August 15, 1994, at 10:00 A.M., and are included here as additional information:

The recirculation spray system heat exchangers are currently in dry lay-up and will remain in dry lay-up for the remainder of Cycle 4 operation.

There are no current plans to increase the number of tubes plugged in the recirculation spray heat exchangers during the remainder of Cycle 4 operation. Plugging, if needed, normally occurs following tube inspections conducted during refueling outages.

The last recorded river water temperature was 75*F and has been trending downward due to cooler average daily temperatures and recent precipitation.

The river water temperature reached a naximum value of 83 F in 1994 and the site maximum temperature of 86'F was recorded in 1988.

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