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Charles E. Norelius, Director "s HEMORANDUM FOR:
Division of Reactor Projects, RIII 06 FROM: Harold R. Denton Director !
Office of Nuclear Reactor Regulation
SUBJECT:
TECHNICAL SPECIFICATION INTERPRETATION ON SNUBBERS !
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By memorandum dated April 18, 1986, you requested an interpretation of the Technical Specification on snubber surveillance. This request provided a copy of a memorandum from M. L. Jordan, SRI, LaSalle to G. C. Wright dated !
February 28, 1986 from which three questions were identified. !
There are some fundamental misconceptions of the TS requirements in Mr. Jordan's memorandum which should be clarified as they relate to the identified questions.
The snubber surveillance requirements related to testing are addressed by
. item e, of specification 4.7.9 which states that these requirements are to be performed during the first refueling and every 18 months thereafter during shutdown. The TS are explicit that the 18 month surveillance is to be performed during plant shutdown. Therefore, this requirement would not be met if the licensee had removed snubbers for testing as planned when the unit was at power.
With regard to the planned testing at power, it is noted that Mr. Jordan told the licensee that they should do an engineering analysis to determine how many snubbers could be removed before system operability is affected. The TS operability requirements can not be waved based on engineering analysis. The requirements of specification 3.7.9 are explicit with regard to those snubbers to which the LC0 apply:
"The only snubbers excluded from the requirement are those installed on non-safety related systems and then only if their failure or failure of the system on which they are installed would have no adverse effect on any safety-related system."
Thus, the operability requirements for snubbers can not be waved based on engineering analysis.
The TS action statements establish allowable outage times for systems or component addressed by the LCO. These time limits are applicable when the system or component is required to be operable and must be removed from service to perform required surveillance tests. For snubbers, the allowable outage time is 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. When this time limit is exceeded, the associated systems must be considered inoperable and action requirements for those systems must be met. However, the action requirements for associated systems are not applicable if for surveillance testing snubbers are sequentially remnved one at a time and replaced or all snubbers are simultaneously removed i
8707100166 870701 d 2 19B6 PDR FOIA WILLIAM 87-121 PDR
Charles E. Nore11us and replaced as a group at the same time, so long as the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> limit is not ,
exceeded. It should be recognized that the snubber TS are unique in that the i operability requirements do not require consideration of associated system redundancy or impact until a snubber is nut of service in excess of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
Following is our response to the three specific questions identified in your memo. You requested that our responses assume the licensee neither has nor is willing to perform a seismic analysis before removing snubbers from service. As noted in the response to question 1 below, the only analysis related to snubbers required by the TS is that related to snubbers found inoperable. This analysis is not a seismic analysis, but rather an engineering evaluation with regard to the operability of the affected systems, in the absence of a seismic event. Therefore the assumption is not relevant to the responses for these questions.
- 1. When a snubber is removed from a system for testing / surveillance purposes what, if any, portion of the Technical Specification (TS) on snubbers or the system apply?
Normally snubbers would only be removed from a system for testing /
surveillance purposes at a time when the system is not required to be operable. If, however, a snubber is removed from service, for any purpose, for a system which is required to be operable, the action statement for snubbers would apply. The action statement requires that inoperable snubber (s), those removed for testing, be restored to operable service in 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. :
i The action statement also requires that an engineering evaluation of the attached component be performed in accordance with specification 4.7.9.g or that the attached system be declared inoperable. This specification (4.7.9 9) notes that where snubbers are found inoperable, an engineering evaluation is to determine if the components to which inoperable I snubbers are attached were adversely affected to assure that the component remains capable of meeting its designated service. The intent of this requirement is to assure that the system was not adversely affected by the inoperable snubber. This does not relate to the system or components capability to withstand a seismic event. Any degradation in seismic protection due to inoperable snubbers was taken into account in establishing the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> allowed outage time.
When a snubber is removed from service for testing, an engineering evaluation need not be performed. If the snubber is not returned to service in 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, that system would be declared inoperable at this time since the snubber allowable out-of-service time limit would be exceeded.
Because some systems are required to be operable during shutdown, the 18 month surveillance requirement may necessitate the removal of snubbers from those systems for testing. Mr. Jordan's memorandum notes that the licensees method for testing is to remove one or two snubbers from systems which are required to be operable. This is an acceptable approach to testing in this case.
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Charles E. Morelius 2. How many snubbers may be removed at one time, for testing or surveillance activities without affecting system operability?
, The TS does not place a limit on the number of snubbers which can be removed from service. The limiting condition for operation is that all snubbers shall be operable and that with one or more inoperable, all
. inoperable snubbers are to be restored to operable status in 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
The affected systems are only declared inoperable when the snubbers are not restored to operable status after 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
- 3. May the number of snubbers determined in 2 above be removed from multiple systems simultaneously?
The Technical Specifications do not preclude the removal of one or more snubbers from service or from multiple system simultaneously. However, '
the action requirements apply for systems required to be operable when sntcbbers are removed from service in excess of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
Your memo also requested that this clarification of the snubber TS be considered for inclusion in the information notice recommended by the memorandum from A. Gibson, RII to D. G. Eisenhut dated March 17, 1986. Since this response is based on the requirements for snubbers which are explicitly stated in the TS, we do not find that there is a need to issue an information notice on this matter. None of the actions taken by the licensee as described in Mr. Jordan's memorandum are in conflict with the TS requirements.
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. n n, irector Office of Nuclear Reactor Regulation cc: C. J. Paperiello, RIII J. J. Harrison, RIII M. J. Jordan, SRI R. W. Starostecki, RI R. D. Walker, RII E. H. Johnson, RIV D. F. Kirsch, RV