ML20205P811

Application for Amend to License DPR-61,changing Tech Specs to Allow Implementation of Measures Approved by NRC as One Element of Response to Previously Addressed Small Break LOCA Issue

ML20205P811
Person / Time
Site:	Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png
Issue date:	05/14/1986
From:	Opeka J CONNECTICUT YANKEE ATOMIC POWER CO.
To:	Charemagne Grimes Office of Nuclear Reactor Regulation
Shared Package
ML20205P816	List: B12067, Proposed Tech Specs Allowing Implementation of Measures Approved by NRC as One Element of Response to Previously Addressed Small Break LOCA Issue ML20205P811
References
B12067, NUDOCS 8605220013
Download: ML20205P811 (4)

Text

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CONNECTICUT YANKEE ATOMIC POWER COMPANY B E R L I N. CONNECTICUT P o BOX 270 HARTFORD. CONNECTICUT 06141-0270 T E L EPHONE 203-665-5000 May 14,1986 Docket No. 50-213 B12067 Office of Nuclear Reactor Regulation Attn: Mr. Christopher I. Grimes, Director Integrated Safety Assessment Project Directorate Division of PWR Licensing - B U.S. Nuclear Regulatory Commission Washington, D.C. 20555

Reference:

(1) 3. F. Opeka letter to C/ I. Grimes, " Request for Temporary Exemption from Single / Failure Requirements - Probabilistic Safety Study LOCA Anslyses," dated April 22,1986.

(2) 3. F. Opeka letter to' C. I. Grimes, " Request for Temporary Exemption from Single Failure Requirements," dated April 25,1986. >

(3) F. 3. Miraglia letter to 3. F. Opeka, dated April 28, 1986, Exemption From S. ingle Failure Criterion (GDC35).

Gentlemen:

Haddam Neck Plant Proposed Revision to Technical Specifications Emergency Core Cooling Systems In accordance with the commitments contained in References (1) and (2), and pursuant to 10CFR50.90, Connecticut Yankee Atomic Power Company (CYAPCO) hereby proposes (o amend its Operating License, DPR-61, by incorporating the attached proposed change into the Haddam Neck Plant Technical Specifications. This amendment will allow implementation of measures which have been ' approved by the Staff via Reference (3) as one element of our response to the previously addressed small break LOCA issue.

The proposed revision to Technical Specifications 3.6.B and 4.3.B is provided in Attachment 1. In order to use the high pressure safety injection (HPSI) pumps to perform high pressure ricirculation following a small break loss of coolant accident (LOCA), succesiful operation of valves SI-MOV-24 and RH-MOV-874 is required. This change involves performance of monthly surveillance on SI-MOV-24 (on the line from the refueling water storage tank), and on RH-MOV-374 (on the RHR pump discharge to the HPSI pump suction line). The monthly surveillance on these two valves will increase the probabi!ity that the valves are available to perform their function during the small break LOCA. Further information on the use of this path was provided in our exemption request in Reference (1) and (7.) and was approved by the NRC in Reference (3). \

8605220013 860514 ) I PDR ADOCK 05000213 glwfcJ1 CMC'

e During Modes 1, 2 and 3, SI-MOV-24 will be manually cycled approximately 1 inch of stem travel to verify stem movement. Since SI-MOV-24 will not be closed to any measurable extent during the survei!!ance, there will be no effect on safety injection availability. During normal operation, RH-MOV-874 will be fully cycled by closing the electrical breaker in the Primary Auxiliary Building, and opening the valve from the full closed to the full open position and back to the full closed position. Surveillance on RH-MOV-874, will only last for a short time and the probability of a small break loss of coolant accident concurrent with the surveillance is extremely low. If the valve becomes inoperable during this time, RH-V-783 in series with RH-MOV-874 can be closed. Therefore, there will be no measurable impact on HPSI system availability as a result of the surveillance. To assure that the valves are returned to their proper position following the surveillance, the final valve positions will be independently verified. In addition, the conduct of the monthly surveillance for valve operability will be independently verified.

CYAPCO has reviewed the attached proposed change pursuant to 10CFR50.59 and has determined that it does not constitute an unreviewed safety question.

Specifically, the margins of safety as defined in the Technical Specification Bases are maintained. In addition, the probability of occurrence or the consequences of a previously analyzed accident have not been increased and the possibility for a new type of accident not previously evaluated has not been created. This proposed change to the Technical Specifications is an addition to existing surveillance requirements to provide increased reliability to the HPSI method of high pressure recirculation post-LOCA.

CYAPCO has reviewed the proposed revision in accordance with 10CFR50.92, and has concluded that it does not involve a significant hazards consideration.

The basis for this conclusion is that the criteria of 10CFR50.92(c) are not compromised, a conclusion which is supported by our determinations made pursuant to 10CFR50.59. The proposed change does not involve a significant hazards consideration because this change would not:

1) Involve a significant increase in the probability or consequences of an accident previously evaluated. This change is an addition to existing surveillance requirements. The monthly surveillance to be performed on these two valves will increase the probability that the valves are available to perform their function during a small break LOCA.

2) Create the possibility of a new kind of accident from any previously analyzed. Since SI-MOV-24 will not be closed to any measurable extent during the surveillance, there will be no effect on safety injection availability. Surveillance on RH-MOV-874 will last for a short time and the probability of a small bred LOCA concurrent with the surveillance is extremely low. If the valve becomes inoperable during this time, RH-V-783 in series with RH-MOV-874 can be closed. Therefore, there will be no measurable impact on HPSI system availability as a result of the surveillance.

3) Involve a significant reduction in a margin of safety. Performing surveillance on these two valves will provide greater assurance that the valves are operable if required to mitigate a small break LOCA during the recirculation phase of core cooling. The net result is an increase in system availability.

As noted in Reference (1), this preposed technical specification addresses the condition that was discovered as a result of the recently submitted (l)

Probabilistic Safety Study (PSS). Also, as noted above, there is a net safety benefit associated with this proposed technical specification.

The Commission has provided guidance concerning the application of the standards for determining whether a significant hazards consideration exists by providing examples (51 FR 7751) of amendments that are considered not likely to involve significant hazards consideration. Example (ii) relates to "a change that constitutes an additional limitation, restriction or control not presently included in the technical specifications, e.g., a more stringent surveillance requirement."

The proposed change to Technical Specifications 3.6.B and 4.3.B add to existing surveillance requirements and, therefore, are similar to example (ii).

In order to implement our plan to perform a monthly surveillance as described above and in Reference (3), it is necessary for CYAPCO to receive NRC approval of this proposed license amendment within 30 days since the conduct of the most recent test, which was on April 28, 1986. This was the latest time at which the surveillance could have been performed in light of actual plant status and current technical specification requirements on the subject valves.

Therefore, CYAPCO requests exigent approval of this proposed license amendment in accordance with 10 CFR 50.91(a)(6) in order to satisfy the commitments previously reviewed and approved by the NRC Staff.

As indicated in References (1) through (3), CYAPCO is diligently pursuing this issue which arose from the PSS and is requesting exigent Staff approval pursuant to 10CFR50.91(a)(6). Best efforts by CYAPCO have been evident on this issue since its inception. CYAPCO identified the problem via a resource-intensive, voluntary effort. A prompt report pursuant to 10CFR50.72 was provided, followed by an informational letter, an exemption request, a meeting with the Staff, and a confirmatory letter. The revised surveillance proposed herein represents one element of our interim corrective action and is being applied for via this amendment request in a timely fashion.

To enable CYAPCO to meet the desired surveillance internal, we request that the amendment be issued by May 23, 1986. If some additional time is necessary to complete the processing of this amendment, we believe this would still be acceptable in light of the typical tolerance of 25% on a specific surveillance interval.

(1) J. F. Opeka letter C. I. Grimes, dated March 31, 1986,

Subject:

Probabilistic Safety Study - Summary Report and Results.

_4 The Haddam Neck Nuclear Review Board has reviewed and approved the attached proposed revision and has concurred with the above determinations.

In accordance with 10CFR50.91(b) CYAPCO is providing the State of Connecticut a copy of this proposed amendment.

Pursuant to the requirements of 10CFR170.12(c), enclosed with this amendment request is the application fee of $150.00.

If you have any questions, please contact us promptly as we will devote any additional resources necessary to process this request in a timely manner.

Very truly yours, CONNECTICUT YANKEE ATOMIC POWER COMPANY

% F- (G k L

3. F. Opeka' Senior Vice President cc: Mr. Kevin McCarthy Director, Radiation Control Unit Department of Environmental Protection Hartford, Connecticut 06116 STATE OF CONNECTICUT )

) ss. Berlin COUNTY OF HARTFORD )

Then personally appeared before me 3. F. O- 'ka, who being duly sworn, did state that he is Senior Vice President of Connect- t Yankee Atomic Power Company, a Licensee herein, that he is authorized to execute and file the foregoing information in the name and on behalf of trie Licensees herein and that the statements contained in said information are true and correct to the best of his knowledge and belief.

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4lotary Pupc Ny testmwan Expires March 31,1988