ML20235H094

Safety Evaluation Supporting Amend 23 to License NPF-38

ML20235H094
Person / Time
Site:	Waterford
Issue date:	09/22/1987
From:	Office of Nuclear Reactor Regulation
To:
Shared Package
ML20235G981	List: ML20235G978 ML20235H094
References
GL-84-15, NUDOCS 8709300365
Download: ML20235H094 (6)

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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO. 23 TO FACILITY OPERATING LICENSE NO. NPF-38 LOUISIANA POWER AND LIGHT COMPANY WATERFORD STEAM ELECTRIC STATION, UNIT 3 DOCKET N0. 50-382

1.0 INTRODUCTION

By application dated March 26, 1987, as supplemented by letters dated May 15, July 24 and August 24, 1987, Louisiana Power and Light Company (LP&L or the licensee) requested changes to the Technical Specific 6tions (Appendix A to Facility Operating License No. NPF-38) for Waterford Steam Electric Station, Unit 3.

The proposed changes would revise the surveillance requirements associated with demonstrating operability of the emergency diesel generators (EDGs) in order to minimize engine stress and wear in response to Generic Letter 84-15.

2.0 DISCUSSION On July 2,1984, the staff issued Generic Letter (GL) 84-15 entitled,

" Proposed Staff Actions to Improve and Maintain Diesel Generator Reliability," which seeks to attain and maintain high reliability of diesel generators.

The licensee's response for GL 84-15 is contained in the above-referenced letters.

The changes proposed by the licensee are in 3 major catagories, as follows:

1) changes to reduce the number of EDG starts required under specific conditions; 2) changes in the methodology of EDG testing to minimize engine wear; and 3) revision to Table 4.8-1 to reduce the frequency of EDG testing as a function of the number of EDG failures.

The staff evaluation of the changes requested by the licensee is included in this report. The staff evaluation is keyed to the specific sections of the Waterford TS for which changes have been requested.

3.0 EVALUATION This evaluation covers changes to Section 3/4.8.1," A.C. Sources" of the Waterford TS requested by the licensee.

Each change is identified by the appropriate paragraph number anri/or title, and is evaluated individually.

8709300365 070922 ADOCK0500g2 PDR P

.' 1 3.8.1.1 Action a. and b.

In this change, the orginal Action a. is expanded to become Action a.

and b. In the existing TS, Action a. covers the loss of either an offsite power source or the loss of an EDG.

The proposed Action a.

covers inoperability of an offsite power source, only, and the proposed Action b. covers inoperability of one EDG, only. 'In addition to separating the two operating conditions, the requirement to test the EDG(s) "within I hour and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter" is deleted.

For both proposed Actions a. and b., the new requirement is to test the EDG(s) separately within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. There is no requirement for additional testing within the 72-hour LCO period, and the testing requirement in proposed Action b. is further qualified to be required only if the EDG inoperability was due to any cause other than preplanned preventive maintenance.

The changes proposed by the licensee regarding EDG testing during a LC0 are identical to those proposed and approved for use at North Anna Unit 2. The basis for staff acceptance is contained in Section 3.3.1 and 3.3.2 of the staff safety evaluation in support of Amendment No. 48 to the North Anna TS which was forwarded to the utility as an enclosure to a staff letter dated April 25, 1985.

In addition, the proposed changes are consistent with the objective of Generic Letter 84-15 with regard to reducing the number of starts experienced by EDGs.

For the preceding reasons, the staff therefore concludes that the proposed changes to existing Action a. are acceptable.

3.8.1.1 Action c In this change, existing Action b. becomes Action c. which covers the condition of one offsite A.C. circuit and one EDG inoperable.

This action is further modified to delete the requirement to test the remaining EDG "within one hour and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter" and substitutes the requirement to test the remaining EDG within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. The proposed change also qualifies the EDG testing requirement such that testing need only be done if EDG inoperability was due to any Cause other than prepisnned preventive maintenance. A third change covers the situation where either the inoperable offsite A.C.

circuit or EDG is restored to operable status within the requisite 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

At this point, the appropriate Action (a. or b.) becomes dominant, and the time to restore the remaining A.C. source (offsite A.C. circuit or EDG) is based on the time of the initial loss of the remaining inoperable A.C. source. The final change to this Action adds the clarification that a successful test of an EDG in Action c satisfies the same requirement for an EDG test in Action a. or b.

Deletion of thc requirement to test EDGs "within ona hour and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter" was addressed in the discussion i

for Action a. and b., above, and is acceptable for the reason stated.

Substitution of the requirement to test the remaining EDG within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> is consistent with the recommendations in GL 84-15 and is also acceptable.

The proposed change regarding reversion to Action a. or b.

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. following restoration of an A.C. source in Action c. is considered by the staff to be a clarification of the intent of the existing TS and is therefore acceptable.

The staff also agrees that a successful test of an EDG under Action c. satisfies the EDG test requirement in Action a. and b. This proposed change-is, therefore, also acceptable.

3.8.1.1 Action d.

Existing Action c. becomes Action d., and references to Action a. or

b. is changed to Action b. or c.

These are editorial changes necessary to be consistent with the preceding changes and are, therefore, acceptable.

i 3.8.1.1 Action e.

In this change, existing Action d. becomes Action e., and the require-ment to test the EDG's "within one hour and once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter" is deleted.

A requirement to test the EDG's within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> is substi-tuted for the existing test requirement.

This change also includes a statement regarding reverting to Action a. upon restoration of an offsite A.C. circuit, and that Action a. be based on the time of initial loss of the remaining inoperable offsite A.C. circuit.

The final change includes a statement to the effect that successful testing of the EDGs under Action e. satisfies the requirement for EDG testing in Action a.

The above change to the EDG testing requirement is consistent with the objectives of GL 84-15 and is, therefore, acceptable.

The state-ment regarding reverting to Action a. is, in the staff's view, a clarification of the intent of the existing TS and is, therefore, acceptable.

This includes using the time of the initial loss of the remaining inoperable offsite A.C. circuit as the base for Action a.

1 The staff agrees with the licensee that successful EDG testing under l

Action e. satisfies the requirements for EDG testing in Action a.

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Therefore, this last change in Action e. is also acceptable.

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3.8.1.1 Action f.

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In this change, existing Action e. becomes Action f.

The change also 1

includes a statement regarding reverting to Action b. following restoration to operable status of one EDG, and that Action b. be based on the time of initial loss of the remaining inoperable EDG.

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The statement regarding reverting to Action b. is, in the staff's view, a clarification of the intent of the existing TS and is, therefore, acceptable.

This includes using the time of the initial loss of the remaining inoperable EDG as the base for Action b.

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-4.8.1.1.2 A footnote is added to this surveillance which allows prelubing the EDG in accordance with manufacturer's recommendations prior to all planned sta rts.'

This change is consistent with the objectives of GL 84-15 and current staff thinking with regard.to reducing engine wear as a conse-quence of testing.

The proposed change is, therefore, acceptable.

4.8.1.1.2.a.5

1wo' changes are proposed for this sur'vellance.

The first change deletes the requirement to load the EDG~to " greater than or equal to 4400 KW" and substitutes "an indicated 4200-4400 KW".

A footnote explaining the rationale for the change is also added.

The footnote also states that loads in excess of the 4200-4400 KW band for special testing under direct monitoring of the manufacturer or momentary variations due to changing bus loads will not invalidate a test under this surveillance.

The second change adds another footnote which allows the EDG to be loaded in accordance with manufacturer's recommen-dations except that at least once per 184 days the EDG will be loaded in 176 seconds.

The staff has recognized that requiring EDGs to be loaded to " great'er than or equal to KW" has probably caused EDGs to be routinely overloaded, possibly. with detrimental effects.

By establishing an operating band, EDGs can be tested adequately without overloading and without concern for violating applicable TS.

The staff considers the elimination of routine overloading to be consistent with the objectives of GL 84-15 with regard to minimizing stress and wear on EDGs. The proposed operating band for the purpose of this surveillance is, therefore, acceptable.

The staff recognizes the potential for load variations due to changes on the bus.

The staff agrees that momentary variations due to changing bus conditions shall not invalidate the test. Therefore, the portion of the footnote pertaining to load variations is also acceptable.

Rapid loading of EDGs can cause thermal stresses which, in turn, can be detrimental to the EDGs.

By taking a longer time to load the EDGs, these stresses can be substantially reduced.

Therefore, the licensee's proposal to load the EDGs in accordance with manufacturer's recommendations is consistent with the objectives of GL 84-15 with regard to minimizing stress and wear on EDGs.

The licensee's proposal is, therefore, acceptable.

4.8.1.1.2.C.3 The licensee has proposed an addition to this surveillance which states that EDG operability will not be affected by failure of the fuel properties to meet the guidelines in ASTM-D975-1977.

The licensee's proposal is based on corrective action to return the fuel oil supply to within acceptable limits being initiated within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

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'e The fuel oil properties covered by this surveillance do not have an immediate impact on EDG operability.

These properties, which include such things as sulphur, ash content, and copper corrosion will affect long term life and efficiency of a diesel engine, but will have negli-gible affect in the short term.

Corrective action to return the fuel oil supply to within acceptable limits, if initiated within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, would be more than adequate to preclude any EDG degradation.

The licensee's proposed change is, therefore, acceptable.

4.8.1 1.2.d.6 There are three changes proposed for this surveillance.

The first change deletes the requirement to load the EDG's "to greater than or equal to 4840 KW" and substitutes "to an indicated 4700-4900 KW".

The second change adds a footnote which explains the rationale for the change and is identical to the footnote proposed in TS Surveillance 4.8.1.1.2.a.5.

These two changes are acceptable for the same reasons presented in the evaluation of the changes to 4.8.1.1.2.a.5, above.

The third change in this surveillance adds a footnote pertaining to the requirement to perform surveillance 4.8.1.1.2.d.3b within 5 minutes after completing this surveillance.

The footnote states that if surveillance 4.8.1.1.2.d.2b is not satisfactorily completed, it is not necessary to repeat the preceding 24-hour test.

Instead, the EDG may be operated at an indicated 4200-4400 KW for one hour or until internal operating temper-atures have stabilized.

At this point, 4.8.1.1.2.d.3b would be attempted again and, if successfully completed, would be a valid test.

The purpose of surveillance 4.8.1.1.2.d.3b is to demonstrate the ability of EDGs to' start and accept load from a hot condition.

This ability can be demonstrated whenever the EDG operating temperatures have reached their normal values for full load operation and have stabilized. The length of operating time required to reach this point is of no importance with regard to this surveillance.

The staff agrees with the licensee that the 24-hour test need not be repeated, and the proposed change is therefore acceptable.

4.8.1.1.3 Reference to Regulatory Position e.3.b of Regulatory Guide 1.108 is deleted from this section of the TS, and reference to Table 4.8-1, Table 4.8-la, and attachments to Table 4.8-la is added.

Tables 4.8-1 and 4.8-la include specific actions to be followed when EDG failures for the last 20 and/or last 100 valid start attempts exceed a specified value.

Table 4.8-1, Table 4.8-la, and attachments to Table 4.8-la are included as part of GL 84-15.

The purpose of these tables and attachments

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is to eliminate excessive EDG testing as a function of the number of j

failures, and to implement some definitive criteria regarding actions to be taken with respect to unreliable EDGs.

The inclusion of these

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tables and attachments in the Waterford TS is consistent with the i

objectives of GL 84-15 and is, therefore, acceptable.

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4 The TS changes proposed by the licensee will result in the reduction of both the number of fast starts and the total number of tests experienced by the EDGs at Waterford 3.

These reductions, in turn, will reduce wear and stress on the EDGs, which is consistent with the objectives of GL B4-15.

The TS changes proposed by'the licensee are, therefore, acceptable.

4.0 CONTACT WITH STATE OFFICIAL The NRC staff has advised the Administrator, Nuclear Energy Division, Office of Environmental Affairs, State of Louisiana of the proposed determination of no significant hazards consideration.

No comments were received.

5.0 ENVIRONMENTAL CONSIDERATION

The amendment relates to changes in installation or use of a facility component located within the restricted area.

The staff has determined that the amendment involves no significant increase in the amounts and no significant change in the types of any effluents that may be released offsite and that there is no significant increase in individual or cumulative occupational radiation exposure.

Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).

Pursuant to 10 CFR 51.22(b), no environmental I

impact statement or environmental assessment need be prepared in connection with the issuance of this amendment.

6.0 CONCLUSION

Based upon its evaluation of the proposed changes to the Waterford 3 Technical Specifications, the staff has concluded that:

there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and such activities will be conducted in compliance with the Commission's regulations and the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

The staff, therefore, concludes that the proposed changes are acceptable, and they are hereby incorporated into the Waterford 3 Technical Specifications.

Dated: September 22, 1987 Principal Contributor:

E. Tomlinson

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