ML20055G400

Application for Amend to License DPR-65,revising Tech Spec 3/4.7.6 Re Control Room Emergency Ventilation Sys

ML20055G400
Person / Time
Site:	Millstone
Issue date:	07/13/1990
From:	Mroczka E NORTHEAST NUCLEAR ENERGY CO., NORTHEAST UTILITIES
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20055G401	List: B13576, Proposed Tech Specs Re Control Room Emergency Ventilation Sys ML20055G400
References
B13576, NUDOCS 9007230135
Download: ML20055G400 (4)

Text

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To' General Offices

• Selden Street. Berhn, Connecticut 3 ' ' "

P.O. BOX 270 HARTF040, CONNECTICUT 061414270 k k J ' " " ,[.7,,*,,"r',Z",

C'% *"""*" (203) 60L4000 July 13, 1990 f

Docket No. 50-336 B13576 Re: 10CFR50.90 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555 L Gentlemen:

Millstone Nuclear Power Station, Unit No. 2 Proposed Change to Technical Specifications Control Room Emeraency Ventilation Systems Pursuant to 10CFR50.90, Northeast Nuclear Energy Company (NNECO) hereby proposes to amend its Operating License No. DPR-65 by incorporating the y changes identified in Attachment 1 into the Technical Specifications of Millstone Unit No. 2. There is an inconsistency between the present Control Room Emergency Ventilation System (CREVS) Technical Specification 3/4.7.6 and Electrical Power Systems Technical Specification 3/4.8.1.2. Specifically, Technical Specification 3/4.8.1.2 allows for one (1) Diesel Generator to be j out of service (inoperable) for maintenance with the plant in Modes 5 and 6.

l Technical Specification 3/4.7.6 as written requires both Diesel Generators l o)erable in Modes 5 and 6. This proposed change corrects the conflict between tie two (2). Technical Specifications and allows for one (1) Diesel Generator to be inoperable in Modes 5 and 6.

Specifically, the proposed change adds an asterisk to the Modes 5 and 6 '

section under the Limiting Condition For Operation (LCO) for Specifica-tion 3.7.6.1 and clarifying remarks explaining the applicability as follows:

l L In Modes 5 and 6, when a Control Room Emergency Air Clean up system is determined to be inoperable solely because its- emergency- power source is inoperable, or solely because its normal power source is inoperable, it may be considered OPERABLE for the purpose of satis-fying the requirements of 3.7.6.1 Limiting Condition for Operation, provided: (1) its corresponding normal SI emergency power source is OPERABLE; and (2) all of its redundant system (s), subsystem (s),

train (s), component (s) and device (s) are OPERABLE, or likewise satisfy the requirements of the specification. Unless both condi-tions (1) and (2) are satisfied within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, then Limiting Condition for Operation (LC0) 3.7.6.1.a or 3.7.6.1.b shall be invoked as applicable. t 9007230135 900713 DR, ADOCK0500gg}6 ,

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U.S. Nuclear Regulatory Commission B13576/Page 2 .

July 13,1990 )

Backaround On May 4, 1989(I) the NRC Staff issued Millstone Unit No. 2 Resident  !

Inspection Report 50-336/89 05. This inspection report identified an issue in which a diesel generator was taken out of service due to i routine service water maintenance activities. This, in effect, made i the associated CREVS train inoperable ser the existing Technical Specification. The opposite train of tie CREVS was not placed in the recirculation mode as per the requirements of Technical Specifi-cation 3.7.6.1.a. The inspection report also identified a commit-ment by NNECO to submit a Technical Specification change request to )

correct the inconsistency between the two (2) Technical Specifica- j tions. NNECO reaffirm j)thiscommitmentinalettertotheNRCStaff dated April 30, 1990.

1 Sianificant Hazards Consideration NNECO has- reviewed the proposed changes in accordance with 10CFR50.90 and has concluded that they do not-involve a significant hazards consideration in that these changes would not:  ;

1. Involve a significant increase in the probability or conse-quences of an accident previously evaluated. There are no '

design basis accidents that are impacted by this proposed change to Technical Specificathns. This does not affect or have any potential impact upon any of the design basis types of F accidents previously analyzed. Failure modes associated with this proposed change will not result in an initiating event that will result in a design basis accident and will not change or adversely impact the probability of a failure of any safety  :

systems. The proposed modifications to the Technical Specifi-cations will not change or adversely impact the performance of any safety systems. Providing for one (1) emergency diesel generator inoperable during Modes 5 and 6 without entering an action statement under Technical Specification 3.7.6.1 is l consistent with existing accommodation invoked under Technical l: Specification 3.0.5 for CREVS in Modes 1, 2, 3, and 4, and with existing Technical Specification 3.8.1.2 in Modes 5 and 6.

l (1) J. P. Durr letter to E. J. Mroczka, " Millstone Unit No. 2 Resident i Inspection 50 336/89-05 (2/11/89 - 3/23/89)," dated May 4, 1989. '

(2) E. J. Mroczka letter to T. T. Martin, " Millstone Unit No. 2, Response to l Potico of Violation, inspection Report No. 50-336/90-01," dated April 30, L 1990.

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4 U.S. Nuclear Regulatory Commission B13576/Page 3 July 13, 1990 This change simply resolves inconsistencies between Technical Specifications.

2. Create the possibility of a new or different kind of accident from any previously analyzed. This proposed Technical Specifi-cation change does not modify the existing plant response such that it can be considered a new accident. There are no new credible failure modes associated with this change. The results and effects of the change are consistent with those accidents already analyzed for. This change clarifies and ensures consistency between existing Technical Specification requirements. No physical modifications to equipment or equipment operation have been made. All other surveillance requirements and bases have remained unchanged.

3. Involve a reduction in the margin of safety. All design bases associated with this Technical Specification have remained unchanged. The design basis for CREVS is to maintain Control Room environment for 30 days continuous occupancy without exceeding 5 Rem whole body dose per 10 CFR 50, Appendix A-GDC

19. CREVS OPERABILITY in Modes 3, 4, 5, and 6 is to cope with a hypothet.ical release outside containment, particularly in the case of oulti-unit sites where CREVS must be OPERABLE at all times, illowing for one emergency diesel generator inoperable without entering an action statement under Technical Specifica-tion 3.1.6.1 is consistent with the existing accommodation invoked under Technical Specification 3.0.5 for CREVS in Modes 1, 2, 3, and 4, and with existing Technical Specification 3.8.1.2 in Modes 5 and 6. Any system failure which renders one CREVS inoperable (except emergency power source) will invoke the LCO under existing Technical Specification 3.7.6.1.

Therefore, no reduction in the margin of safety is considered to occur as a result of the proposed change.

The Commission has provided guidance concerning the application of standards in 10CFR50.92 by providing certain examples (51FR7751, March 6, 1986) of amendments that are considered not likely to involve a significant hazards consideration. Although the changes proposed herein are not enveloped by a specific example, this proposed change is intended to correct an inconsis-tency between Technical Specification 3/4.7.6 and 3/4.8.1.2 during Modes 5 and 6 and enable Technical Specification 3.7.6.1 to accommodate one emergency diesel generator inoperable without entering an LC0 action statement.

The Millstone Unit No. 2 Nuclear Review Board has reviewed and approved the attached proposed revision and has concurred with the above determinations.

NNECO respectfully requests that this proposed change be issued prior to the start of the next refueling outage currently planned for September 1990 to avoid a similar situation as noted above. NNECO also requests this license l

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. r U.S. Nuclear Regulatory Commission B13576/Page 4 July 13, 1990 amendment be effective as of the date of its issuance, to be implemented ,

within 30 days of issuance. ,

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

Very truly yours, NORTHEAST NUCLEAR ENERGY COMPANY 4%

E. J y 6zki (/

Senior Vice President cc: Mr. Kevin McCarthy Director, Radiation Control Unit Department of Environmental Protection Hartford, Connecticut 06116 T. T. Martin, Region I Administrator G. S. Vissing, NRC Project Manager, Millstone Unit No. 2 P. Habighorst, Resident Inspector, Millstone Unit No. 2 W. J. Raymond, Senior Resident Inspector, Millstone Unit Nos.1, 2, and 3 STATE OF CONNECTICUT ss. Berlin -

. COUNTY OF HARTFORD Then personally appeared before me, E. J. Mroczka, who being duly sworn, did state that he is Senior Vice President of Northeast Nuclear Energy Company, a Licensee herein, that he is authorized to execute and file the foregoing information in the name and on behalf of the Licensee 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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