ML20094J336
| ML20094J336 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 03/05/1992 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20094J334 | List: |
| References | |
| GL-90-09, GL-90-9, NUDOCS 9203120339 | |
| Download: ML20094J336 (2) | |
Text
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1.0 INTRODUCTION
By letter dated August 1, l!91, the licensee requested revitions to Technical trecif ication (TS) 3/4.7.8, " Snubbers," and associated Cases to change the snutber visual inspection intervals arid corrective actions.
TS 3/4.7.8 imposes suruillance requirenents for visual inspec'.1on un t 'l sof oty-related snubbers.
The preposed change provides alternative requirements for snubbers bastd on the guidance contained in NRC Generic Letter (GL) 90-09, " Alternative Requirements for Snubber Visual Inspection Intervals and Corrective Actions,
dated December 11, 1990. Based on discussions with the his0 staff, the licensee revised its request by letter dated February 19, 1992, to more closely conform with the recorrendations of GL 90-09. As this revision is more conservative in defining snubber visual inspection acceotance criteria than the original proposal, the staff's proposed no significant hazardt determinat1or., dated September 4,1991, remains valid.
2.0 EVALUATION The current requirements in TS 3/4.7.8 specify a schedult for snubber visual inspections that is based on the number of inoperable snubbers f ouno durirg the previous visual inspection.
A visual inspection is the observation of the condition of installed snubbers to identify these that are damaged, degraded, or inoperable as caused by physical rneans, leakage, corrosion or environmental exposure. To verify snubber operability, a f unctional ttst is performed that involves removing the snubber and performing a bench test. A visual inspection complements the functional test and provides additional confidence in snubber operability.
The schedules for visual inspection and for functional testing assume that refueling intervals will not exceed 18 months.
Because the current visual inspection schedule is based only on the number of inoperable snubbers found during the last visual inspection irrespective of the size of the snubber population, plants with large numbers of r.ubbers find that the visual Qa.
inspection schedule is excessively restrictive, wra 88' All safety-related snubbers are required to be operable to ensure that the structural integrity of all safety-related systems is maintained during and gon to following a seismic or other event initiating dynamic loads.
The visual u
inspection frequency is based on raintaining a constant level of snubber gg protection during a seismic or severe transient event.
In order to establish oc the insrection f requency for each type of snubber on a safety-related system, it was assumed that the frequency of snubber failure and the initiating Sa.
event is constant with time, and that the f ailure of any snubber could cause ro the system to be unprotected. The alternate inspection schedule contained in GL 90-09 is based on the number of unacceptable snubbers found during the previous inspection in proportion to the sizes of the snubber populations or
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2 categories. Ite licenste bus determined that the proposto charge to TS 3/4.7.8 will reduce future operationel radiation exposure to personnel, and would be highly cost effective.
The NR sta11 ies stated in GL 90 09 that the alternathe schedule for vi*,ual inspections maintains the sarne contidence level as the existing schedult, anc 9tnerall) will al b the licensee to perform visual inspections anc tale corrective actions curit,9 plant outages. 1he staff has revi o ed the proposed chat.ges to TS 3/4.7.8 and finds that they are consistent with the guidarce containtd in GL 90 09.
Therefore, the license atendment is acceptable.
3.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Missouri State official was notified of the proposed issuance c' the amendment. The State official had no comments.
4.0 ENVIRONMENTAL CON 51DLRAT10N This amendment involves changes to requirements with respect to the instal-lation or use tf a f acility conpcnent located within the restricted area as defined in 10 CFR Part EC and changes to surveillance requirenents. The staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any ef fluents that may t,e releaseo ofisite and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has treviously issued a proposed finding that this amendment involves no significant hazar ds consideration and there has been no public comment on such finding (56 TR 43817).
Accordingly, this amendment meets the eligibility criteria f or categorical e>clusion set forth in 10 CFR 51.n(cH9).
Pursuant to 10 CFR 51.22(b), no environmental impact statement or environnental assessr4nt need be prepared in connection with the issuance of this antendment.
5.0 CONCLUSION
The staff has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance % t the health and safety of the public will not be endangered by operation in itt try oued manner, (2) such acth ities will be conducted in compliance with the Commission's regulations, anc (3) the issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public, principal Contributor:
J. Lombardo Date: March 5,1992
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