ML20217M346
| ML20217M346 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 03/25/1998 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20217M327 | List: |
| References | |
| NUDOCS 9804080079 | |
| Download: ML20217M346 (4) | |
Text
p.m at-
}p UNITED STATES g
j.
NUCLEAR RECULATORY COMMISSION t
WASHINGTON, D.C. 200 6 4001 4
%.....j SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO.123TO FACILITY OPERATING LICENSE NO. NPF-30 UNION ELECTRIC COMPANY CALLAWAY PLANT. UNIT 1 DOCKET NO. 50-483 l
1.0 INTRODUCTION
By letter dated August 8,1997, and January 16,1998, Union Electric Company (UE), proposed an amendment to the operating license of the Callaway Plant, to revise the plant Technical Specifications (TS). The proposed revisions involve Table 3.3-3, Engineered Safety Feature Actuation System Instrumentation, functional units 4.b.2 and S.a.2. Specifically, UE proposes to edit Table 3.3-3 to make ihn entries for the number of main steam and feedwater isolation
)
system (MSFIS) channels condstent with the requirements of the solid state protection system (SSPS), add a clarification note, delete action statements, and change Table 4.3-2 functional units 4.b.2 and 5.a.2 surveillance requirements from a quarterly slave relay test to a monthly staggered actuation logic test.
The January 16,1998, supplemental letter provided additional clarifying information and did not change the staff's original no significant hazards consideration determination published in the Federal Register on December 17,1997 (62 FR 66143).
2.0 BACKGROUND
On October 1,1996, the staff approved Callaway Plant TS amendment number 117 which replaced fixed logic portions of the MSFIS with programmable digital processor equipment. The new configuration utilized programmable logic controllers and associated application software.
With that change, MSFIS automatic actuation logic functional units were added to TS Table 3.3-3. The intent was to add requirements for MSFIS similar to those of the SSPS. Action
- Statements 27a and 34a were added to TS Table 3.3-3 to provide guidance in the event of an inoperable MSFIS logic channel. In addition, MSFIS surveillance requirements were added to functional units 4.b and S.a of Table 4.3-2.
3.0 EVALUATION i
The SSPS and the MSFIS are arranged in a tandem configuration and together form the logic functions for main steam and feedwater isolation.' Circuits in each SSPS train provide i
coincidence logic and the appropriate signals are sent, via a slave relay, to an associated MSFIS train. Each MSFIS train consists of three programmable logic controller (PLC) channels j
i i
'9804000079 980325 W4' DR ADOCK 05000483 p
PDR g
o
1 4-8 2--
.1 1
! hat use a two-out-of-three. voting scheme to drive actuation relays that energize or deenergize '
' the solenoids required for isolation valve operation. No software or hardware component changes are proposed in the licensee's submittal.
J 3.1 Table 3.3-3, Functional Units 4.b.2 and 5.a.2 Proposed Change The licensee proposes to change MSFIS table designations associated with the Total Number
' Channels to 2, Channels to Trip to 1, and Minimum Channels Operable to 2.
Evaluation
- For SSPS steam line and feedwater isolation logic functions, TS Table 3.3-3 specifies Total
' Number of Channels as 2, Channels to Trip as 1, and Minimum Channels Operable as 2. As 1
- applied to the SSPS logic functions, the term " channels", in Table 3.3-3, refers to SSPS actuation trains. For MSFIS logic functions TS Table 3.3-3 specifies Total Number of Channels as 3 per SSPS train, Channels to Trip as 2 per SSPS train, and Minimum Channels Operable as 2 per SSPS train. As applied to MSFIS logic functions, the term " channels" refers to MSFIS PLC channels. After implementing the then new TS designations for MSFIS logic functions, the licensee determined that the nomenclature used in Table 3.3-3 (channel versus train) was misleading and confusing since the term " channels" referred to both SSPS actuation trains and j
MSFIS PLC channels. The proposed changes would also make the term " channels" for MSFIS logic functions refer to MSFIS actuation trains." As described below in Section 3.2, the licensee proposes clarification regarding PLC channels. The staff finds the proposed change consistent with the requirements for the SSPS and editorial in nature. Therefore, the staff finds the proposed change acceptable.
3.2 Table Notation Proposed Chance The licensee proposes to add table notation: +++ Each MSFIS channel (train) requires a minimum of two programmable logic controllers to be OPERABLE.
Evaluation The MSFIS consist of two independent actuation trains with each train configured in a two out of three PLC logic channel design. The proposed change is added to clarify that a minimum of
' two PLCs are required in each MSFIS train for operability. The staff considers the change editorial and therefore, acceptable.
q r
g
f
~ J 3.3 Action Statements 27a and 34a Prooosed Chance The licensee proposes to delete MSFIS action statements 27a and 34a and to utilize SSPS actions statements 27 and 34.
Evaluation Action statements 27a and 34a were previously added to Table 3.3-3 to provide guidance in the i
event of an inoperable MSFIS PLC channel. Action statements 27a and 34a require the plant to be in HOT STANDBY within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> when two of the three PLC channels per MSFIS train become inoperable. The loss of the two required PLC channels or all three PLC channels constitutes an inoperable MSFIS train. After implementation of the TS, the licensee determined that Action Statements 27a and 34a do not provide action if all three PLC channels in a MSFIS train become inoperable. For that case, the licensee determined Technical Specification 3.0.3 requires the plant to be in HOT STANDBY within 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br />. However, the licensee determined that since steam and feedv.ater isolation signals are generated in the SSPS and passed to the MSFIS, the intent of action statements 27a and 34a was to provide actions consistent with those for the SSPS. Therefore, the licensee maintains that actions required for loss of a MSFIS train should be no more restrictive than actions required for the loss of a SSPS train. Action Statements 27 and 34 require the plant to be in 'iOT STANDBY within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> when one train is determined inoperable. This is consistent witi NUREG-1431, Revision 1, Westinghouse Standard Technical Specifications, and is basec on the tandem configuration of the SSPS and j
MSFIS. Therefore, the staff finds the proposed changes acceptable.
,l 3.4 Table 4.3-2, Functional Units 4.b.2 and 5.a.2 Prooosed chance The licensee proposes to change the MSFIS automatic actuation logic and actuation relays surveillance requirement for functional units 4.b.2 and 5.a.2 from a quarterly slave relay test to a monthly staggered actuation logic test.
Exaludon Coincidence logic circuits of the SSPS send isolation signals, via.a slave relay, to the MSFIS.
The logic channels of the MSFIS determine the appropriate signals that are routed to the appropriate actuation relay for valve isolation. The intent of the new quarterly slave relay surveillance requirement was to test the slave relay and the MSFIS PLC logic channels. After a review of Generic Letter 96-01, Testing of Safety Related Logic Circuits," the licensee determirsed the surveillance requirements for the automatic actuation logic and actuation relays should be reclassified as an actuation logic test and not a slave relay test. The proposed change is consistent with the surveillance requirements of the SSPS and consistent with t-
'e1 4-L.
NUREG-1431, Revision 1, Westinghouse Standard Technical Specifications. Therefore, the l-staff finds the proposed change acceptable.
i J3.5 Conclusion The staff has reviewed UE's proposed changes to the Callaway Plant TS to modify the l
description of the number of MSFIS channels, add a clarification note, delete and replace action ~
'i statements, and change a slave relay test to an actuation Icgic test. The changes improve TS l
clarity, are consistent with SSPS TS requirements, and are consistent with NUREG-1431, Revision 1. Based on the review of UE's submittal, the staff concludes that the above TS changes are acceptable.
l l
'H l
f 4.0 ' STATE CONSULTATION i.
,in accordance with the Commission's regulations, the Missouri State official was notified of the proposed issuance of the amendment. The State official had no comments.
'j
5.0 ENVIRONMENTAL CONSIDERATION
i.
The amendment changes a requirement with respect to installation or use of a facility i
component located within the restricted area as defined in 10 CFR Part 20 and changes surveillance requirements. The NRC staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that l
may be released offsite, and that there is no significant increase in individual or cumulative 4
occupational radiation exposure.- The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no L
public comment on such finding (62 FR 66143). Accordingly, the amendment meets the
[
L eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.
6.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above, that: (1) there
' s reasonable assurance that the health and safety of the public will not be endangered by i
b operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
c A. Bryant Principal Contributor:
Date: March 25, 1998.
l' d
fi I
.. 6 i
_m._.____-_
h-
' ' ' '