ML20236A824

Safety Evaluation Supporting Amend 28 to License DPR-21

ML20236A824
Person / Time
Site:	Millstone
Issue date:	03/08/1989
From:	Office of Nuclear Reactor Regulation
To:
Shared Package
ML20236A803	List: ML20236A802 ML20236A808 ML20236A824
References
NUDOCS 8903200183
Download: ML20236A824 (3)

Text

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. . . .y Ni UNITED STATES -

['f .y NUCLEAR REGULATORY COMMISSION O  :: E WASHINGTON, D. C. 20555 >

SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION i

RELATED TO AMENDMENT NO. 28 TO FACILITY OPERATING LICENSE NO. DPR'-21 NORTHEAST NUCLEAR ENERGY COMPANY l

MILLSTONE NUCLEAR POWER STATION, UNIT NO.1 ,

DOCKET NO. 50-245 l

1.0 INTRODUCTION

j By letter dated October 13, 1988, the Northeast Nuclear Energy Company'(NNECO or the licensee) submitted a request for changes to the Technical Specifications 4 (TS) for Millstone Nuclear Power Station, Unit No. 1. '

J The amendment will revise the TS'to provide clarifying information for '

, determining required inspection intervals and establishes criteria for snubbers 1 that may be exempted from being counted as inoperable.  ;

2.0 EVALUATION The current TS for Millstone Unit No. 1 require visual inspection of the j snubbers. The inspection interval for performing the visual inspection is also i defined in the TS and the interval is directly related to the results of,the j previous snubber inspection. In general, the required inspection interval is {

18 months 25% if no snubbers were found to be inoperele at the last j

. inspection. However, as the number of inoperable snuLoers increases, the l required inspection interval decreases, with the shortest required inspection interval being 31 days. This inspection interval is defined in TS 4.6.I.1.

TS Bases 4.6.I state that snubbers for which "...the cause of rejection... is cle5rly established and remedied for that snubber and for any other snubbers that may be generically susceptible...may be exempted from being counted as inoperable." However, it should be noted that this clarification of the definition of inoperable snubber does not exist in the Limiting Conditions for

.0peration or Surveillance Requirements of TS 3/4.6.I.

By letter dated March 14, 1988 NNECO reported that, during a November 16, 1987 drywell entry, it was noticed that one of the hydraulic snubbers was leaking l fluid and its reservoir level was low (this event was also reported in Licensee '

Event Report 87-043-00 on December 16,1987). As a result of this finding, NNEC0 stated that a visual inspection of all safety-related snubbers in l

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containment was performed to ensure-that this condition did.not exist on any l of the remaining snubbers. The results-of this inspection indicated that a H r

total of'two snubbers were found to be-low in hydraulic fluid and both. failed-operability tests and were declared inoperable. The two snubbers were.

subsequently disassembled and were found to have failed.as the result of improper installation of seals.

NNECO,.in its; March 14, 1988 letter, stated that a reduced inspection .i interval, based upon Technical Specification acceptance criteria, is not necessary because:

1. The failure was identified as improper installation, not 'as the result of degradation or aging.

2. All inaccessible safety-related' hydraulic snubbers were inspected.

during the November 19.87' shutdown.

3.- Corrective actions were taken.. Mechanical repairs were . completed and maintenance personnel training has been revised. -j

'Thus, NNEC0' stated that the Tichnical Specifications do not require a reduced '

visual: inspection interval for snubbers.

The staff reviewed the information in the licensee's letter and Licensee Event

' Report and on April 6', 1988, in a letter to the licensee, stated the  ;

circumstances resulting in declaring the two snubbers inoperable do not meet '

the TS criteria for reductions to the visual inspection interval.

By letter dated October 13, 1988, the licensee submitted a request which would 1

provide clarifying information in the TS concerning required inspection ,

intervals and criteria for snubbers that may be exempted from being counted as '

inoperable. Specifically, the proposed change states:

"When the cause of the rejection of a snubber is clearly established and remedied for that snubber and for any other snubbers that may be generically susceptible, that snubber may be exempted from being counted j as inoperable. Generically susceptible snubbers are those which are of a specific make or model and have the same design features directly related to rejection of the snubber by visual inspection, or are similarly located or exposed to the same environmental conditions such as temperature, radiation and vibration."

The staff has reviewed this proposed change to the TS and finds the inclusion of this statement in TS 4.6.I.1 reiterates statements in TS Bases 4.6.I and, as confirmed in the staff's April 6, 1988 letter, conforms to the staff's position on snubber operability and inspection intervals. Therefore, the staff finds this change to the TS acceptable.

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3.0 ENVIRONMENTAL CONSIDERATION

This amendment changes a surveillance requirement for a facility component located within the restricted area as defined in 10 CFR Part 20. 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. The Commission has previously published a ,'

proposed finding that the amendment involves no significant hazards consideration and there has been no public comment on such finding. Accordingly, the-amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 651.22(c)(9). Pursuant to 10 CFR 651.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.

(.0 CONCLUSION We have concluded, based on the considerations discussed above, that (1) there is reasonable assurance that tho health and safety of the will not be endangered by operation in the proposed manner, and (2)such public

' 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.

Dated: March 8, 1989 Principal Contributor: Michael L. Boyle

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