ML20205T135

Application for Amends to Licenses DPR-57 & NPF-5,modifying Tech Spec Core Spray Sparger Differential Pressure Instrumentation Alarm Setpoints to More Accurately Reflect NSSS Vendor Recommendations.Fee Paid

ML20205T135
Person / Time
Site:	Hatch
Issue date:	03/27/1987
From:	James O'Reilly GEORGIA POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20205T140	List: ML20205T135 ML20205T176
References
SL-1529, TAC-65248, TAC-65249, NUDOCS 8704070220
Download: ML20205T135 (7)

Text

- . .___-

-. Georg!a Fbwer Company

+- 333 Piedmont Avenue Atfanta, Georgia 30308 Telephone 404 526 7851 Ma.hng Address:

Post Office Box 4545 Atlanta, Georgta 30302 <

James P. O'Reilly trv scult+vn enec syshyn Senior Vice Premdent Nuclear Operations SL-1529 0865C March 27, 1987 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555 NRC DOCKETS 50-321, 50-366 OPERATING LICENSES DPR-57, NPF-5 EDWIN I. HATCH NUCLEAR PLANT UNITS 1 AND 2 REQUEST TO REVISE TECHNICAL SPECIFICATIONS:

SETPOINTS ON CORE SPRAY BREAK DETECTION INSTRUMENTATION Gentlemen:

In accordance with the provisions of 10 CFR 50.90, as required by 10 CFR 50.59(c)(1), Georgia Power Company hereby proposes changes to the Plant Hatch Units 1 and 2 Technical Specifications, Appendix A to Operating Licenses DPR-57 and NPF-5.

i The proposed changes would modify the Technical Specifications instrumentation alarm setpoints Coreto Spray sparger differential pressure more accurately reflect NSSS vendor recommendations. The proposed instrumentation setpoint will assure the design function of alerting the reactor operators of a potential break in the Core Spray sparger piping located inside the reactor pressure vessel.

Enclosure 1 provides a detailed description of the proposed changes and the basis for the change.

Enclosure 2 details the basis for our determination that the proposed changes do not involve a significant hazards consideration.

Enclosure 3 arovides aage change instructions for incorporating the proposed changes 'nto the init 1 and Unit 2 Technical Specifications.

The proposed changed Technical Specifications pages follow ,

Enclosure 3.

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L k U. S. Nuclear Regulatory Commission March 27, 1987 Page Two Payment of the filing fee in the amount of one hundred and fifty dollars is enclosed.

In order to allow time for procedure revision and orderly incorporation into copies of the Technical Specifications, we request

that the proposed amendment, once approved by the NRC, be issued with an effective date to be no later than 60 days from the issuance of the amendment.

1 Pursuant to the requirements of 10 CFR 50.91, a copy of this letter and all applicable enclosures will be sent to Mr. J. L. Ledbetter of the Environmental Protection Division of the Georgia Department of Natural Resources.

Mr. James P. O'Reilly states that he is Senior Vice President of Georgia Power Company and is authorized to execute this oath on behalf of Georgia Power Company, and that to the best of his knowledge and belief, the facts set forth in this letter and enclosures are true.

GEORGIA POWER COMPANY

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By: \\ mwst((O h di James P, O'Reill 0

Sworn to and subscribed before me thih7t day of March 1987.

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- ' Notary Public GKM/lc m ,7 ' ' ,

Enclosures c: Georgia Power Company U. S. Nuclear Regulatory Commission Mr. J. T. Beck N n, Jr. Dr. J. N. Grace, Regional Administrator Mr. H. C. Nix, Jr. Mr. P. Holmes-Ray, Senior Resident G0-NORMS Inspector - Hatch Mr. G. Rivenbark, Licensing Project Manager State of Georgia Mr. J. L. Ledbetter 0865C 1

L.____

l l ENCLOSURE 1 l

NRC DOCKETS 50-321, 50-366 OPERATING LICENSES DPR-57, NPF-5 EDWIN 1. HATCH NUCLEAR PLANT UNITS 1 AND 2 l REQUEST TO REVISE TECHNICAL SPECIFICATIONS:

SETPOINTS ON CORE SPRAY BREAK UETECTION INSTRUMENTATION BASIS FOR CHANGE REQUEST Propa ed Changes:

l l The proposed changes would revise the Unit 1 and linit 2 Technical Specifications Core Spray (CS) sparger differential pressure instrument setpoints to "<3.1 psid great.er (less negative) than the normal indicated AP at rated core power and f1'ow." This represents a new setpoint for the Unit 1 Technical Specifications in which no setpoint is presently given, and a change to the current value given in the Unit 2 Technical Specifications. The instrumentation provides no trip functions and acts only to alert the operator of a possible break in the CS sparger piping.

A footnote has been added to the table in which the setpoint appears in the Unit 1 Technical Specifications to delineate the fact that the instrumentation provides an alarm function only. . This footnote also adopts the equivalent action requirements provided in the Unit 2

Technical Specifications.

Background:

The CS line break instrumentation has been provided to detect a gross l failure in the CS piping loi:ated inside the reactor pressure vessel (RPV)

(between the nozzle and the shroud) during reactor operation 'at rated-power conditions. If a break occurs, the instrumentation should provide this information by actuating a control room annunciator. The CS line break instrumentation is connected to measure the ~ differential pressure across the reactor shroud. The reference differential pressure (or normal aP) will vary at different operating conditions with intact CS piping. The current Unit 2 setpoint is overly restrictive and results in i

nuisance alarms, because of the normal variation of differential pressure I with reactor power and flow changes.

Basis for Proposed Changes:

The proposed setpoint is based upon Hatch-specific recommendations made by General Electric and General Electric Service Information Letter (SIL)

No. 300. The SIL recommends that, relative to the CS sparger differential pressure setpoint the Technical Specifications be written to apply only to plant operation at rated power and flow. The current Unit 2 Technical Spe:ffication 4.5.3.1.c.? states that the setpoint should correspond to " normal" indicated 4P. The " normal" AP is dependent upon the )ower and flow caerating condition. Therefore, the l Technical Specifications will be clarified to read: "f3.1 psid greater i

0865C El-1 3/27/87

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ENCLOSURE 1 REQUEST TO REVISE TECHNICAL SPECIFICATIONS:

SETPOINTS ON CORE SPRAY BREAK DETECTION' INSTRUMENTATION BASIS FOR CHANGE REQUEST (less negative) than the normal indicated AP at rated core power and flow." The revised setpoint was determined using a suitably conservative analytical limit of 3.6 psid, and the methodology presented in Regulatory Guide 1.105. This proposed Technical Specifications setpoint is substantially higher than the current Unit 2 alarm setpoint of 1.0 psid.

However, the new analytical limit is still well below the differential pressure change which would occur should there be a break in the CS sparger piping while operating near rated power and flow. The CS sparger break detection instrumentation will continue to fulfill its design function of alerting the operator of a potential break in the sparger piping located inside the RPV, but the number of nuisance alarms alarms willi decrease. The instrumentation was designed to be effective onl when core flow is between 90 percent and 100 percent cf rated (SIL-300)y .

Implementation of a Hatch-specific instrument setpoint will reduce the occurrence of alarms which are not indicative of a break, yet still will allow break detection within the system's design function.

The instrument alarm setpoint will now appear in Table 3.2-6,

" Instrumentation Which Initiates or Controls Core Spray" in the Unit 1 l Technical Specification. A footnote has been added stating that the instrumentation performs an alarm function only. The footnote also adopts the action requirements of the corresponding Unit 2 Technical l Specifications. This action requirement will call for monitoring the core spray differential pressure at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> if the instrumentation is inaperable. This is appropriate because the instrument performs nu mtrol or initiation function, but only provides an alarm to indicate a ;e.sible loss of integrity of the core spray sparger piping. If the instrumentation is inoperable, but the differential pressure can still be verified to be within limits, safe operation of the Unit can continue. If the differential pressure can not be verified, the associated loop of core spray would be declared inoperable. Adding the footnote will also make the Technical Specifications of the two units more consistent. I 0865C El-2 3/27/87

ENCLOSURE 2 NRC DOCKETS 50-321, 50-366 OPERATING LICENSES DPR-57, NPF-5 EDWIN I. HATCH NUCLEAR PLANT UNITS 1 AND 2 REQUEST TO REVISE TECHNICAL SPECIFICATIONS:

SETP0lNT5 ON CORE SPRAY BREAK DETECTION INSTRUMENTATION 10 CFR 50.92 EVALUATION Pursuant to the requirements of 10 CFR 50.92, Georgia Power Company has evaluated the proposed amendments for Plant Hatch Units 1 and 2 and has determined that their adoption would not involve a significant hazards consideration. The basis for this determination is as follows:

Proposed Changes:

These proposed changes would revise the Unit 1 and ' Unit 2 Technical Specifications on Core Spray (CS) sparger differential pressure instrumentation alarm setpoints to reflect vendor recommendations. This represents a new setpoint for the Unit 1 Technical Specifications in which no setpoint is presently given, and a change to the current value given in the Unit 2 Technical Specifications. These changes affect an alarm function only; no trip setpoints are being revised.

In addition, the proposed Specification will be written to correspond to a single operating condition (rated power and flow). This has been recommended by the vendor in an effort to clarify the word " normal" in the current Unit 2 Specification.

Adding an action requirement to the Unit 1 Technical Specifications which will call for monitoring the Core Spray differential pressure at least i once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> if the instrumentation in inoperable, will also not involve a significant hazard. The instrument performs no control or i initiation function, but only provides an alarm to indicate a possible '

loss of integrity in the core spray sparger piping. If the differential pressure can be verified to be within limits with the instrumentation inoperable, the unit can continue to operate in a safe manner.

Basis:

The proposed setpoint change does not involve a significant increase in the probability or consequences of an accident, because the revised setpoints for both units were determined based on the differential pressure change which would occur in the event of a break in the CS sparger piping. The setpoints include appropriate margins to the analytical limits. With the revised alarm setpoints, the CS sparger differential pressure instrumentation in both Unit 1 and Unit 2 will 0865C E2-1 3/27/87

j ENCLOSURE 2 REQUEST TO REVISE TECHNICAL SPECIFICATIONS:

SETPOINT5 DN CORE SPRAY BREAK DETECTION INSTRUMENTATION 10 CFR 50.92 EVALUATION i continue to fulfill its design function. Changing the Specification to correspond to a single operating condition .(rated power and flow) does not involve a significant increase in the probability or consequences of an accident because it simply clarifies the word " normal" in the current Unit 2 Specifcation. Also, adding an action requirement to the Unit 1

. Technical Specifications which will call for monitoring the CS differential pressure every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> if the instrumentation is inoperable will not significantly increase the probability of consequences of an accicent. The instrument performs no control or initiation function, but j only provides an alarm to indicate a possible loss of integrity in the core spray sparger piping. If the differential pressure can be verified to be within limits with the instrumentation inoperable, the unit can continue to operate in a safe manner.

The possibility of a different kind of accident from any analyzed previously is not created by these changes, since the design function of the system, as described in the FSAR, is not affected. The instrument performs an alarm function only.

Margins of safety are not significantly reduced by the changes, because revising the setpoint and clarifying the wording in the Technical Specifications will still ensure that a break occurring within the CS sparger piping will be detected (within the capabilities of the instrumentation). The occurrence of false alarms will be reduced.

0865C E2-2 3/27/87

m ENCLOSURE 3 NRC DOCKETS 50-321, 50-366 OPERATING LICENSES DPR-57, NPF-5 EDWIN I. HATCH NUCLEAR PLANT UNITS 1 AND 2 REQUEST TO REVISE TECHNICAL SPECIFICATIONS:

e SETPOINT5 ON CORE SPRAY BREAK UETEF, TION IN5TRUMENTATION PAGE CHANGE INSTRUCTIONS The proposed change to the Technical Specifications (Appendix A to Operating Licenses DPR-57 and NPF-5 would be incorporated as follows:

UNIT 1 Remove Page Insert Page 3.2-14 3.2-14 UNIT 2 Remove Page Insert Page l

3/4 5-6 3/4 5-6 i

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0865C 3/27/87 e , q -