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Application for Amend to License NPF-49,incorporating Changes Recommended in GL 93-05 Re DG SR & Other DG SR Concerning Cold Starts
	ML20078Q030
Person / Time
Site:	Millstone
Issue date:	12/09/1994
From:	Debarba E; NORTHEAST NUCLEAR ENERGY CO.
To:	; NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20078Q033	List: B14971, Application for Amend to License NPF-49,incorporating Changes Recommended in GL 93-05 Re DG SR & Other DG SR Concerning Cold Starts; ML20078Q034;
References
	B14971, GL-93-05, GL-93-5, NUDOCS 9412210119
	Download: ML20078Q030 (13)
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j. f-I 107 Saldaa Street 8ertia, cr 06037 Northeast l

, sh8N Northeast Utilities Service Company P.O. Box 270 !

Hartford, cr 06141-0270 (203) 665-5000 l December 9, 1994 Docket No. 50-423 I B14971 ,

l U.S. Nuclear Regulatory Commission '

Attention: Document Control Desk '

Washington, DC 20555 Millstone Nuclear Power Station, Unit No. 3 Proposed Revision to Technical Specifications :

Diesel Generator Surveillance Requirements Introduction Pursuant to 10CFR50.90, Northeast Nuclear Energy Company (NNECO) hereby proposes to amend Operating License No. NPF-49, by incorporating the changes identified herein into the Technical Specifications of Millstone Unit No. 3, The proposed changes incorporate the recommendations of Generic Letter (GL) 93-05ni (Section' 10.1 of the GL) related to the diesel generator (DG) ,

surveillance requirements and other DG surveillance requirements '

related to the cold starts. This submittal supersedes our request made on April 1, 1993. tai Description of the Proposed Changes l NNECO proposes to modify the Millstone Unit No. 3 Technical Specifications by incorporating recommendations included' in ,

GL 93-05 and modifying the DG surveillance requirements related to {

the cold start. r (1) J. G. Partlow letter to All Holders of Operating Licensees or Construction Permits for Nuclear Power Reactors, "Line-Item Technical Specification Improvements to Reduce Surveillance Requirements for Testing during Power Operation (Generic !

Letter 93-05)," dated September 27, 1993.

(2) J. F. Opeka letter to the U.S. Nuclear Regulatory Commission,

" Proposed Revision to Technical Specifications -

A. C. i Sources," dated April 1, 1993. I a ~s es mx22 mx 9. 9412210119 941209 }I PDR ADOCK 05000423 e P ppg ,

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U.S. Nuclear Regulatory Commission B14971/Page 2 December 9, 1994 l l

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Generic Letter 93-05 i NNECO proposes to modify Section 3/4.8.1 of the Millstone Unit No. 3 Technical Specifications, "AC Sources, OPERATING," by incorporating recommendations regarding DG surveillance requirements included in GL 93-05 (Section 10.1 of the GL) except two. We believe that implementing the recommendation of GL 93-05 to r oad an operable DG during certain conditions is inappropriate for the Millstone Unit No. 3 plant configuration. This action could subject the loaded DG to grid faults which could adversely affect its ability to perform its safety function. If the surveillance on the operable DG was being performed because of the inoperability of the other DG, the plant would be left with no operable DGs. Also, this was the subject of recent EDSFI inspections at the Millstone units. The NRC Regional Staff recommended that we should not synchronize the operable DG to the grid during this operability test. It is noted that NNECO has established a procedure / practice not to synchronize the operable DG to the grid during the test. In addition, the current Action Statements 'b' and 'c' of Section 3.8.1.1 do not require such loading and connection to the offsite grid.

The second item concerns the allowed time frame to determine the operability of one DG when the opposite train DG has been declared inoperable. GL 93-05, Item 10.1, specified that this determination must be made within eight hours. The currently approved Technical Specifications for Millstone Unit No. 3 (Specification 3. 8.1.1, Action b) and Specification 3.8.1, Action B.3 of NUREG-1431,

" Standard Technical Specifications - Westinghouse Plants," dated September 1992, allow 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months to make this determination.

Operability testing of a DG is required by Millstone Unit No. 3 Technical Specification 3/4.8.1.1 whenever a DG is declared inoperable due to any cause other than preplanned preventative maintenance or testing. Since there are many potential failures of DG subsystems that would not be classified as a common mode failure yet would cause a DG to be declared inoperable, this technical specification requirement can cause unnecessary testing of the operable DG when the alternate DG is declared inoperable due to inoperable support equipment or an independently testable componnnt. NUREG-1366 stated: "The NRC Staff recor.unends that the requirements to test the remaining diesel generacor(s) when one diesel generator is inoperable due to any cause other than preplanned preventive maintenance anc testing limited to those situations where the cause for inoperability has not been

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conclusively demonstrated to preclude the potential for a common i mode failure. However, when such testing is required, it should be !

performed within eight hours of having determined that the diesel is inoperable." However, NUREG-1431 allows 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months to determine .

the cause of the inoperable DG failure before requiring testing of the remaining operable DG.

Therefore, it is NNECO's position that 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months is an appropriate i time frame for complying with the intent of GL 93-05. This position is consistent and similar in nature to that approved by the NRC Staff for North Anna (Docket Nos. 50-338 and 50-339, 1 Amendment dated July 16, 1994) plant. The following section .,

describes the proposed changes. They are labeled by the title and section number utilized in GL 93-05. i Emergency Diesel Generator Surveillance Requirements -(Section l 10-1 of GL 93-05) l

1. Section 3.8.1.1 The proposed changes to Action, Statements 'a' and 'e' l revise the action requirements for starting a non- !

affected DG when the limiting conditions for operation of !

the AC electrical power sources are degraded. Action l Statements 'a' and 'c' are being changed as follows: ,

Action 'a': Delete the sentence "If either diesel :

generator has not been successfully tested within the l past 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , demonstrate its OPERABILITY by performing i Surveillance Requirement 4.8.1.1.2.a.5 separately for each such diesel generator within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months ."

Action 'e': Delete the following sentences " demonstrate f the OPERABILITY of the two diesel generators by J sequentially performing Surveillance Requirement 4.8.1.1.2.a.5 on both diesel generators within eight '

hours, unless the diesel generators are already operating;" and "A successful test (s) of diesel generator OPERABILITY per Surveillance Requirement 4.0.1.1.2.a.5 )

performed under this Action Statement for the OPERABLE diesel generator satisfies the diesel generator ~ test requirement of Action Statement a."

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U.S. Nuclear Regulatory Commission B14971/Page 4 December 9, 1994 When a DG itself is inoperable (not including a support i system or independently testable component), the other DG 1 should be tested only once and within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months unless the absence of any potential common mode failure can be demonstrated. A new footnote is being added to Action Statements 'b' and 'c' and will read as follows: "The OPERABILITY of the remaining diesel generator need not be verified if the diesel generator became inoperable due ;

to: 1) Preplanned preventive maintenance or testing, 2) !

An inoperable support system with no potential common mode failure for the remaining diesel generator, or.3) An independently testable component with no potential common mode failure for the remaining diesel generator."

In addition, the existing footnote for Action Statements

'b' and 'c' (at the bottom of pages 3/4.8-1 and 8-2) is ,

unnecessary; therefore, NNECO is proposing to delete the I footnote.

Add the word "offsite" after the phrase "the remaining" in Action Statement 'c'. Delete the phrase "a or" from the last sentence of Action 'c'.

2. Surveillance Requirements 4. 8.1.1.2.a. 6) and 4.8.1.1.2.b GL 93-05 recommends that the DGs should be loaded in accordance with the vendor recommendations for all test purposes other than the refueling outage loss of offsite power (LOP) and/or engineered safety features (ESF) actuation test signal tests.

The words "in less than or equal to 60 seconds" in Surveillance Requirement 4.8.1.1.2.b have been replaced with the words "in accordance with the manufacturer's recommendation." The words "in accordance with the manufacturer's recommendations" are also added to Surveillance Requirement 4.8.1.1.2.a.6). The term "with a load greater than or equal to 4986 kw" is inserted in Surveillance Requirements 4.8.1.1.2.a. 6) and 4.8.1.1.2.b.

3. Surveillance Requirement 4. 8.1.1.2.g.7 The current technical specification requirement 4.8.1.1.2.g.7 verifies DG hot restart capability by initiating a LOP /ESF actuation test signal within five

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December 9, 1994 l

minutes of completing the DG 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months run. This test creates significant scheduling demand during an outage by !

reducing schedule flexibility and imposing unnecessa:y operating burden. GL 93-05 recommends the hot-start test following the 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months DG test should be a simple DG start test. It also states that if the hot-start test is not performed within the required five minutes following the i 24-hour DG test, it should not be necessary to repeat the 1 24-hour DG test. The only requirement should be that the hot-start test is performed within five minutes of operating the DG at its continuous rating for two hours or until operating temperatures have stabilized.

Therefore, a reference to Surveillance Requirement 4.8.1.1.2.g.6.b) has been changed to Surveillance Requirement 4.8.1.1.2.a.5. Surveillance Requirement 4.8.1.1.2.a.5 verifies that the DG starts on a manual or auto start signal, attains generator voltage and '

frequency of 4160 i 420 volts and 60 i 0.8 hz. Since the LOP /ESF test will no longer be used to demonstrate DG hot I restart capability, the note at the bottom of page 3/4 8-6 is appropriately reworded to include 4.8.1.1.2.a.5. Additionally, the requirement to run the DG for one hour to achieve normal operating temperature is increased to two hours. The latter requirement is more conservative than the current one-hour requirement ,

and will continue to establish the required conditions to demonstrate DG hot restart capability. A footnote is being added to indicate that DG loadings for the 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months test may include gradual loading as recommended by the 1 manufacturer.

Other DG Surveillance Requirements

1. Surveillance Requirement 4.8.1.1.2 The existing footnote at the bottom of page 3/4 8-3 is deleted. The new note has been added and it will state:

"All planned starts for the purpose of these surveillances may be preceded by an engine prelube period." The surveillance requirement to which this note is applicable is changed from 4.8.1.1.2.a to apply to all of the surveillance requirements for 4.8.1.1.2 because the engine prelube option is applicable to all the tests.

The footnote to Surveillance Requirement 4.8.1.1.2.b

U.S. Nuclear Regulatory Commission B14971/Page 6 December 9, 1994 ,

(i.e., Page 3/4 8-4) is no longer needed since it is covered by the proposed footnote (see above) . Therefore, it is being deleted.

2. Surveillance Requirements 4.8.1.1.2.a.5),

4.8.1.1.2.g.4.b), 4.8.1.1.2.g.5), and 4.8 d.1.2.g.6.b The term " ambient condition" is replaced h the term

" standby conditions" in Surveillance dequirement 4.8.1.1.2.a.5). The term " standby conditions" is

, inserted in Surveillance Requirements 4.8.1.1.2.g.4.b), ,

4.8.1.1.2.g.5) and 4.8.1.1.2.g.6.b. The term " standby conditions" more accurately describes the condition in which the DGs are maintained and accounts for the !

continual operation of the jacket water and lube oil warming systems. ,

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3. Surveillance Requirements 4.8.1.1.2.a.5), 4.8.1.1.2.b and l 4.8.1.1.2.h This surveillance requirement specifies, among other I requirements, that after a start signal, the DG gradually accelerates to at least 508 rpm with generator voltage )

and frequency at 4160 i 420 volts and 60 i 0.8 hz. With regard to this surveillance, the NRC in its letter dated September 23, 1993, m stated that the NRC considers the ,

parameters of significance to be the frequency, voltage I and time following the start signal; i.e., the DGs should I be able to accept loads in proper sequence and continue l to carry safety-related electrical loads within the required time after a start signal. Since the generator is directly connected to the engine and the two must turn at the same speed, the speed specification is redundant.

This is recognized in the Improved Standard Technical Specifications (NUREG 1431) where comparable engine speed requirements do not appear. Therefore, for Millstone Unit No. 3, the speed reference is being deleted.

l (3) A. W. DeAgazio (U.S. Nuclear Regulatory Commission) letter to Mr. T. C. Feigenbaum, " Inconsistent Technical Specification I Surveillance Requirement, Electric Power System, A. C. Sources j (TAC M87706)," dated September 23, 1993, i l

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December 9, 1994 The proposed changes contained herein (i.e., related to GL'93-05 and other changes described above) are similar in nature to those ;

approved by the NRC Staff for the Seabrook Station, Unit No. 1 l (Docket No. 50-443).

Attachments 1 and 2 contain the marked-up and retyped pages of the J Millstone Unit No. 3 Technical Specifications. These pages reflect ,

the currently issued version of the technical specifications. They )

do not include changes previously proposed in the submittel dated l August 25, 1994. m Therefore, NNECO suggests that the NRC staff j check with NNECO for continuity with ' the Millstone Unit No. 3 ;

Technical Specifications prior to issuance. l l

Safety Assessment l Generic Letter 93-05 ,

l In December 1992, the NRC issued NUREG-1366, " Improvements to Technical Specifications Surveillance dequirements," to provide the results of a comprehensive examination of surveillance testing required by technical specifications. The NRC determined that, while the majority of testing at power is important, safety can be improved, equipment degradation decreased, and unnecessary burden on personnel resources eliminated by reducing the amount of testing that the technical specifications require at power operating I conditions. On September 27, 1993, the NRC issued GL 93-05, it encouraged licensees to propose changes to their technical specifications that are consistent with the GL guidance.

The proposed changes to the DG operability testing surveillance requirements are consistent with the intent of GL 93-05. The proposed changes will modify the requirement for the DG operability testing when the other DG is inoperable, delete the requirement for DG operability testing when one or both offsite AC sources are inoperable, eliminate fast loading of DGs except for the 18-month test, and modify the hot restart test from the 24-hour loaded test run for the DGs. Char.ging the operability testing requirements and the fast loading surveillance requirements will improve the DG overall reliability by reducing unnecessary starting and loading thereby reducing the wear and tear on those machines. However, (4) J. F. Opeka letter to the U.S. Nuclear Regulatory Commission, i

" Generic Letter 93-05, Additional Information," dated

August 25, 1994.

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B14971/Page 8 i

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'when DG reliability testing is required because of a potential common mode failure,'this change will require starting the other ,

DG. .

i The proposed changes to the technical specifications include a revision to the method of verifying DG hot restart capability after ,

the 24-hour run test as required by Surveillance Requirement j 4.8.1.1.2.g.7. The technical specification presently requires that i this test is performed by initiating a LOP signal in conjunction i with the safety injection (SI) signal within five minutes after completion of the 24-hour run. The DG is required to start within.

11 seconds and be loaded with the accident loads. This requirement l limits outage scheduling flexibility and imposes operational .

burdens. The proposed change is to verify the hot restart capability through performance of the test in accordance with !

Surveillance Requirement 4.8.1.1.2.5.a, which allows for' starting ,

the DG either manually or automatically and verifying the generator attains rated voltage and frequency without loading the DG with LOP /SI loads. ;

Demonstrating DG hot restart capability without loading the engine j with LOP /SI loads does not invalidate or reduce the effectiveness {

of either test, provided normal operating temperature conditions i are achieved prior to demonstrating hot restart capability. . Normal ;

operating temperature conditions will be assured by performing the i test within five minutes of completing the 24-hour DG run. If'for l

some reason the surveillance cannot be conducted within the five minute time period, the engine may be brought to operating temperature conditions by operating at a load of greater than or ,

equal to 4986 kw for two hours, or until operating temperature has l stabilized. _i Regulatory Guide 1.108, Position C.2.a. (5) , which is the basis for ,

the requirement to perform the LOP /SI test immediately after the ,

24-hour tests, states that the purpose of the requirement is to ;

" demonstrate functional capability at full load temperature conditions." Functional capability, i.e., the ability of the DG to i start from normal operating temperature, can be adequately demonstrated by either manually or automatically starting the DG from normal operating temperature. Sequencing on the LOP /SI' loads does not contribute to verifying that the DG will start from normal operating temperature.

Therefore, the proposed changes to incorporate the guidance of GL 93-05 do not adversely affect public health and safety.

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U.S. Nuclear Regulatory Commission B14971/Page 9 December 9, 1994 Other DG Surveillance Requirements The current footnote to Surveillance Requirement 4.8.1.1.2 is being replaced with a footnote that states: "All planned starts for the :

purpose of these surveillances may be preceded by an engine prelube period." In addition, this footnote is also applicable to all DG test starts. This is consistent with the Improved Standard Technical Specifications (NUREG 1431).

Replacing the term " ambient condition" with " standby conditions" and inserting the term " standby conditions" will improve the clarity of technical specifications. The term " standby conditions" more accurately describes the conditions which the DGs are maintained. It recognizes the fact that the DGs are maintained j prelubed and warm by the cooling water and lube oil system. -

The proposed change also eliminates reference to diesel engine rpm i in various surveillance test acceptance criteria retaining only reference to generator voltage and frequency. These two terms are redundant since the engine and the generator are connected and must ,

rotate at the same speed. l The proposed changes will continue to verify that the DGs are operable and hence no design basis analyses are affected by the proposed changes. Therefore, the proposed changes will not adversely affect the health and safety of the public.

Significant Hazards Consideration NNECO has reviewed the proposed changes in accordance with 10CFR50. 92 and concluded that the changes do not involve a significant hazards consideration (SHC). The basis for this conclusion is that the three criteria of 10CFR50. 92 (c) are satisfied. The proposed changes do not involve a SHC because the changes would not:

i 1. Involve a significant increase in the probability or i consequences of an accident previously analyzed, l l

The proposed changes revise the action requirements regarding i operability testing of a non-affected DG when the other DG is ;

inoperable, delete the requirement for operability testing of the DGs when one or both offsite AC sources are inoperable and i eliminate the fast loading of DGs except for the 18-month l test. These changes will improve DGs performance by reducing

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B14971/Page 10 December 9, 1994 l i

I the number of unnecessary quick starts and by requiring more ;

appropriate testing of the DGs when there is a potential for common mode failure. The proposed change, to revise the i method of verifying DG hot restart capability after a 24-hour run without loading the DG with LOP /SI load, meets an intent of Regulatory Guide 1.108, Pusition C.2.a.5, which states the !

purpose of the test as to " demonstrate functional capability at full load temperature conditions." Functional capability of the DG can be adequately demonstrated by manually or automatically restarting the DG within five minutes after a ,

24-hour test run without loading it with LOP /SI loads, 3 provided that a full load temperature condition is maintained j prior to restart. The proposed DG restart method does not reduce the effectiveness of the test. The proposed revisions ;

of the DG surveillance requirements will not increase the :

probability of an accident and it will not change the response !

of the DG to a LOP as described in the Millstone Unit No. 3 l FSAR. Since the plant response to an accident will not change, there is no change in the potential for an increase in ,

the consequences of an accident previously analyzed. ll

2. Create the possibility of a new or different kind of an ,

accident previously evaluated. l The proposed changes of the DG surveillance requirements and [

operability testing requirements do not affect the operation ;

or response of any plant equipment or introduce any new [

failure mechanisms. The proposed changes do not affect the test results and the DGs will be verified to be operable and l their response to a loss of voltage will be unchanged. The r plant equipment will respond per the design and analyses and {

there will not be a malfunction of a new or any type introduced by the revision to the DG surveillance ,

requirements. As such, the changes do not create the !

possibility of a new or different kind of accident previously l evaluated.

3. Involve a significant reduction in the margin of safety. .

The bases of Technical Specification 3/4.8, " Electrical Power i Systems," state that the operability of the AC and DC power systems and associated distribution systems ensure that :

sufficient power will be available to supply the safety- l related equipment required for safe shut down and mitigation !

and control of accident conditions. The ba'es also state that s

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,e U.S. Nuclear Regulatory Commission B14971/Page 11 December 9, 1994 the surveillance requirements for determining the operability-of the DGs are in accordance . With the recommendations of Regulatory Guide 1.108, Revision 1. The revisions of ' the surveillance requirements establishes tests that will continue to verify that the DGs are operable and the testing will still meet the intent of Regulatory Guide 1.108, Revision 1.

Operable DGs ensure that the assumptions in the bases of the Technical Specifications are not affected and ensure that the margin of safety is not reduced. Therefore, the assumptions in the bases of the technical specifications are not affected and these changes do not result in a significant reduction in the margin of safety.

Moreover, the Commission has provided guidance concerning ' the application of standards in 10CFR50.92 by providing certain examples (51 FR7751, March 6, 1986) of amendments that are considered not likely to involve a SHC. The changes proposed by this application for license amendment are not enveloped by any of the specific examples. The proposed changes will improve the DG performance by reducing the number of unnecessary quick starts and by requiring more appropriate testing of the DGs when there is a potential for common mode failure. As discussed above, NNECO has concluded that the proposed changes do not involve a SHC.

Environmental Considerations

" NNECO has reviewed the proposed license amendment against the criteria of 10CFR51.22 for environmental considerations. The proposed changes do not increase the type and amounts of effluents that may be released offsite, nor significantly increase individual or cumulative occupational radiation - exposure. Based on the foregoing, NNECO concludes that the proposed changes meet the criteria delineated in 10CFR51.22 (c) (9) for a categorized exclusion from the requirements for an environmental impact statement.

Nuclear Review Board The Millstone Unit No. 3 Nuclear Review Board has reviewed and concurred with the above determination.

Notification of the State of Connecticut In accordance with 10CFR50.91(b), we are providing the State of Connecticut with a copy of this amendment request.

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U.S. Nuclear Regulatory Commission B14971/Pa9a 12 December 9, 1994 Schedule for NRC Approval and Issuance The proposed amendment will enhance the safe operation of the plant and remove unnecessary operational / testing burdens (i.e., the hot restart test following the 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months run test) during the refueling outages. Therefore, we are requesting that the NRC review and approve this proposal prior to the start of the next refueling outage. Carrently, the next refueling outage is scheduled to begin in April 1995. The license amendment will be implemented within 30 days of the date of issuance.

Should you have any questions regarding this submittal, please contact Mr. R. G. Joshi at (203) 440-2080.

Very truly yours, NORTHEAST NUCLEAR ENERGY COMPANY FOR: J. F. Opeka Executive Vice President l

BY: ,

E. A. DeBarba Vice President {

l cc: T. T. Martin, Region I Administrator V. L. Rooney, NRC Project Manager, Millstone Unit No. 3 P. D. Swetland, Senior Resident Inspector, Millstone Unit Nos.

1, 2, and 3 Mr. Kevin T. A. McCarthy, Director Monitoring and Radiation Division l Department of Environmental Protection l 79 Elm Street P.O. Box 5066 Hartford, CT 06102-5066

U.S. Nuclear Regulatory Commission B14971/Page 13 December 9, 1994 Subscribed and sworn to before me this h ik day of /le c pa l,#r , 1994

_ h/1x- lW GA ww Date Commission Expires: / R /3f /<f,

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B14971, Application for Amend to License NPF-49,incorporating Changes Recommended in GL 93-05 Re DG SR & Other DG SR Concerning Cold Starts

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