ML20043H586
| ML20043H586 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 07/20/1987 |
| From: | NRC OFFICE OF SPECIAL PROJECTS |
| To: | |
| Shared Package | |
| ML20043H581 | List: |
| References | |
| NUDOCS 9006260142 | |
| Download: ML20043H586 (2) | |
Text
-_ - - _ _. - - - - - - - - - - -
~
+#po atog e
UMTED STATES NUCLE AR REGULATORY COMMISSION i
\\,e..*,/]
wasrwatow. o. c. nosss L
L SAFETY EVALUATION BY THE OFFICE OF $PECIAL PROJECTS 1
$UPPORTING t.MENDMENT NO. 56 TO FACILITY OPERATING LICENSE NO. DPR.77
[
AND AMENDMENT NO. 49 TO FACILITY OPERATING LtCENSE NO. DPR-79 TENNE $$EE VALLEY AUTHORITY SEQUOYAH NUCLEAR PLANT. UNITS 1 AND 2 DOCKET N05. $0-327 AND 50-328 u
1.0 INTRODUCTION
l By letter dated April 16, 1987 the licensee for the Seouoyah Nuclear Plant, Units 1 and 2, submitted proposed Technical Specification (TS) changes to correct the instrumentation functional requirements for Functional Units 20 (Reactor Trip Breakers) and 21 (Automatic Trip Logic) of Table 3.31 (Reactor TripSystemInstrumentation). These functional requirements are on the total number of channels, the channels to trip, the minimum channels operable, the applicable modes and the action for not meeting the req)uirements.
The licensee is specifically proposing changes to Table 3.3 1 to (1 align on the TS page the requirements for both Functional Units in the startup and power operation modes with the statement "Startup and Power Operation,' (2) delete the **"
under the. applicable modes for both Functional Units for the startup and power operation modes and (3) revise the channels to trip and minimum channels operable requirements for both Functional Units in the shutdown mode.
l 2,0 EVALUATION In Amendment 46, the staff issued page 3/4 J-4 of Table 3.b1 with instrumentation functional requirements for the reactor trip breakers and the automatic trip logic. These are Functional Units 20 and 21, respectively, of this table.
Requirements were specified for both these Functional Units in the startup ans power operation modes and in the shutdown mode.
The requirements specified for the startup and power operation modes for both Functional Units were both I
positioned on the page next to the title of the Functional Units rather than on the lines for 'Startup and Power Operation.' The licensee's first proposed change will position the requirements in the correct location on the page.
This chang ;oes not change any of the requirements for either Functional Unit for the startup and power operation modes. The staff considers this change to be strictly administrative, and therefore acceptable.
The following proposed changes do revise the requirements for the two Functional Units.
For the Functional Units, the licensee indicated that the applicable mode requirement for startup and power operation contains a redundant entry by including the *** mode. The "*" mode exists when the reactor trip breakers are in the closed position, when the control rod drive system is capable of rod
=
O N ON$ 0 00$$17 p
FDC
e o
2 withdrawal, and when fuel is in the reactor vessel. The staff determined that the purpose of this mode recuirement is to ensure the "*" condition is covered during modes 3, 4, and 5.
The way the functional unit requirements have been restructured, the "*" mode is covered by the shutdown subsection and does not need to be included with the startup and power operation subsection. The staff agrees that the deletion of the "*" mode requirement for startup and power operation only removes a redundant entry and therefore is acceptable.
Also, for the same functional units, the Sequoyah Technical Specifications currently indicate O channels to trip and 1 as the minimum channels operable for the shutdown modes 3*, 4* and $*.
The 0 channels to trip is in error, since at least one channel must be operable in order to trip the breaker.
Similarly, the 1 minimum channels operable is not in conformance with Generic Letter 85 09 which requires 2 as the minimum channels operable. The licensee's proposed Technical Specification changes would change the 0 (channels to trip) to a 1 and the 1 (minimum channels operable) to a 2.
We find this change to be consistent with Generic Letter 85 09, and therefore, is acceptable.
3.0 ENVIRONMENTAL CONSIDERATION
These amendments involve a change to a requirement with respect to the installatis or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The staff has determined that the amendments involve no I
significant increase in the amounts, and no significant change in the types, of l
any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Comission has previously issued a proposed finding that these amendments involve no significant hazards consideration and there has been no public coment on such finding. Accordingly, the amendments meet the eli criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9)gibility Pursuant to 10 CFR 51.22(b), no environmental impact statement nor environmental assessment need be prepared in connection with the issuance of these amendments, t
4.0 CONCLUSION
The licensee's proposed Technical Specification changes for the Sequoyah Nuclear Plant, Units 1 and 2, correct errors and clearly delinette functional unit requirements for the reactor trip breakers and automatic trip logic in a manner consistent with Generic Letter 85 09.
We find the proposed changes enhance plant reliability and safety, and therefore find thea to be acceptable.
We have concluded, based on the considerations discussed above, that:
(1) there is reasonable assurance that the health and safety of the will not be endangered by operation in the proposed manner, and (2) public sucil activities will be conducted in compliance with the~Comission's regulations, and the issuance of the amendments will not be inimical to the comon defense and security nor to the health and safety of the public.
Principal Contributors:
A. Toalston and T. Rotella Dated: July 20,1987