ML20134M613

Safety Evaluation Accepting Util 831104 & 850621 Responses to Generic Ltr 83-28,Items 3.1.1 & 3.1.2 Re post-maint Testing of Reactor Trip Sys Components

ML20134M613
Person / Time
Site:	Rancho Seco
Issue date:	08/19/1985
From:	NRC
To:
Shared Package
ML20134G653	List: ML20134G649 ML20134M613
References
GL-83-28, TAC-52955, TAC-53091, TAC-53792, TAC-54102, NUDOCS 8509040194
Download: ML20134M613 (2)

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l SAFETY EVALUATION

[ l 2i GENERIC IMPLICATIONS OF SALEM ATWS EVENT

,s N GENERIC LETTER 83-28. ITEMS 3.1.1 AND 3.1.2

_y a' RANCHO SECO NUCLEAR STATION il DOCKEf NO. 50-312

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] I.- INTRODUCTION On' February 25, 1983, during startup of the Salem Unit 1 plant, both 4; circuit breakers in the Reactor Trip System failed to open automatically

.L upon receipt of a valid trip signal. As a result of that event the NRC's 1 Office of Inspection and Enforcement issued IE Bulletin 83-01 which

'J described the event and requested specified prompt corrective actions by i licensees. As the cause and ramifications.of the event were more clearly j developed, the NRC's Office of Nuclear Reactor Regulation issued on

-; July 8,1983, Generic Letter 83-28, " Required Actions Based on Generic

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Implications of Salem ATWS Events." This letter addressed issues related to reactor trip system reliability and general management capability.

- The letter was sent to all licensees of operating reactors, applicants i for operating licenses and holders of construction permits.

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One of the areas of reactor trip system reliability considered in Generic

'i Letter 83-28 (GL 83-28), is that_ of post-maintenance testirg of reactor

'] trip system components. This is identified in GL 83-28 as Item 3.1.

'; This evaluation addresses the acceptability of the responses to

's parts 3.1.1 and 3.1.2 of this item, provided-by the Sacramento Municipal Utility District (the licensee) for the Rancho Seco Nuclear Station (the e facility). ,

II. EVALUATION Items 3.1.1 and 3.1.2 of GL 83-28 state as follows:

"1. _ Licensees and appli_ cants shall submit the results of' their review of a test and maintenance procedures and Technical Specifications to

' assure that post-maintenance operability testing of safety-related

components in the reactor trip system is required to be conducted

, and that the testing demonstrates that the equipment is capable of performing .its safety functions before being returned to service." ,

d. "2. Licensees and applicants shall submit the results of their check of i - vendor and engineering recommendations to ensure that any

, appropriate test guidance is included in the test and maintenance ,

procedures or Technical Specifications, where required."

I' By letters ' dated November 4,1983 and June' 21,1985, the licensee responded to a numberLof GL 83-28. items, including Items 3.1.1 and 3.1.2.

• Regarding Item 3.1.1, the-licensee's November 4, 1981 letter stated the 8abcock and Wilcox Owners'. Group (BWOG) was developidg generic guidance for determining that' post-maintenance operability testing _ demonstrates

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operability of equipment. The licensee also committed to incorporate this guidance in the utility procedures as appropriate. Regarding the extent of equipment testing performed, the licensee's letter of November 4,1983 stated that facility Administrative Procedure AP.3 -

Work Request, requires that Engineering review the work request prior to initiation of work to determine if functional testing is required and, if so, specify the required testing. Because this procedure did not appear to assure the testing of all components of the reactor trip system, the

licensee was requested to provide such assurance. This was provided by the licensee's letter of June 21, 1985, which further quotes AP.3 as follows

. "Any class I component or system removed frcm service for maintenance, requires post-maintenance testing to assure that the equipment is capable of performing its safety functions before being

returned to service."

l Because all reactor trip system components are categorized as class 1, we

, conclude this procedure provides reasonable assurance that all reactor trip system components will be tested as necessary to demonstrate the

capability to perform the intended safety functions.

Regarding Item 3.1.2, the licensee's letter of June 21, 1985, stated the review of generic guidance for determining that post-maintenance operability testing demonstrates equipment operability, and the review of vendor information provided by the BWOG had been completed. The licensee added that based on this review, the utility had determined the maintenance and surveillance procedures for the reactor trip system do include the test guidance required to demonstrate post-maintenance '

operability of that system.

III. CONCLUSIONS Based on the licensee's confirmation that post-maintenance operability testing is required to be performed on safety-related equipment and that such testing ensures the equipment is capable of performing its safety function prior to return to service, we conclude the licensee has acceptably satisfied the actions requested by Item 3.1.1 of Generic .

Letter 83-28. Accordingly, this item is closed. '

Based on the licensee's completien of a review of the Owners' Group and I

, generic guidance on post-mainter.ance operability testing, and the l

, licensee's determination that facility procedures include the guidance  !

necessary to demonstrate post-maintenance operability of the reactor trip J system, we conclude the licensee has acceptably satisfied the actions requested by Item 3.1.2 of Generic Letter 83-28. Accordingly, this item is closed.

Principal Contributor: l G. Zwetzig 1

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