ML20215K390
| ML20215K390 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 08/25/1986 |
| From: | Nauman D SOUTH CAROLINA ELECTRIC & GAS CO. |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| IEIN-86-003, IEIN-86-3, NUDOCS 8610280153 | |
| Download: ML20215K390 (16) | |
Text
..
roina Electric & Gas Company nA n
Columbia, SC 29218 Nuclear Operations (803) 748-3513 SCE&G O 4/fg All : ga
~'"
August 25,1986 l
t i
f Dr. J. Nelson Grace Regional Administrator U. S. Nuclear Regulatory Commission Region 11, Suite 2900
[
101 Marietta Street, NW Atlanta, GA 30323 l
1
SUBJECT:
Virgil C. Summer Nuclear Station 1
Docket No. 50/395 Operating License No. NPF-12 Limitorque Motor Operators
Dear Dr. Grace:
On August 19,1986 and August 22, 1986, discussions were held between members of your staff and South Carolina Electric and Gas Company (SCE&G) on the environmental qualifications of Limitorque motor operators at the Virgil C. Summer Nuclear Station. These discussions addressed SCE&G's actions relative to IE Information Notice 86-03 concerning the environmental qualifications of the l
internal wiring of Limitorque motor operators. This letter is being submitted to document SCE&G's current status and future slans for resolution of this issue, along with providing a Justification for Continuec Operation (JCO) until all inspections i
and corrective actions are completed.
In response to IE Information Notice 86-03, SCE&G contacted the suppliers of safety related valves with Limitorque motor operators and obtained documentation which supported acceptable environmental qualification. In addition, SCE&G was developing a program which would require mspections of the internal wiring of these valves during regularly scheduled maintenance activities.
As a result of other recent utility inspections, SCE&G has subsequently commenced an engineering evaluation and field inspection of safety-related Limitorque MOVs utilized at the Virgil C. Summer Nuclear Station. There are a total of 131 of these valves in the plant,24 of which are located inside containment and 107 outside containment. To date,19 of these valves have been inspected to verify that the internal wiring is environmentally qualified; 13 of these valves were supplied by Westinghouse, the N555 vendor, while the remaining 6 were balance of plant (BOP) and supplied by various other vendors. All of the BOP valves have been acceptable; however, 6 of the Westinghouse sup alied valves have contained suspect wiring, which has been immediately replacec with qualified wire. Table 1 (see Pac e 2) provides a summary of those valves inspected to date and the results of t1ese inspections.
sk 8610280153 860825 Ib
- 1 PDR ADOCK 05000395 r$'
G PDR s
49
.*fv
- Q
{\\0
).
k
Dr. J. Nelson Grace
. Limitorque Motor Operators Page Two August 25,1986 TABLE 1 Total # of Limitorque motor operators inspected SUSPECT WIRE IDENTIFED CONTAINMENT ACCEPTABLE AND REPLACED INSIDE 1
1 WESTINGHOUSE OUTSIDE 6
5 INSIDE 1
0 OUTSID 5
0 TOTAL 13 6
19 SCE&G intends to continue the inspection and replacement program of the remaining Limitorque motor operators. By September 30,1986, all valves which can reasonably be worked during unit operation will be inspected. Those valves which require alant conditions other than Mode 1 in order to perform the inspections and those w1ich require certain post maintenance testing will be completed during the next outage of sufficient duration.
Enclosure I to this letter is the JCO for the Virgil C. Summer Nuclear Station.
This JCO is the result of an engineering evaluation which assessed the impact of potentially unqualified internal valve wiring on the valve operator operability and determined what, if any, corrective actions need to be implemented until valve o ualifications can be assured. This JCO will be fully implemented by SCE&G no later taan August 29,1986. As operators are inspected and environmental qualifications verified, compensatory actions as required to meet the conditions of the JCO will be discontinued. Based on this JCO, SCE&G has concluded that continued operation of the Virgil C. Summer Nuclear Station is justified and will not adversely impact public health and safety for the period of time until the inspection and replacement program can be implemented.
If you have any questions, please advise.
NVery truVyours,
/
-\\
Y
~
h a man AMM: DAN /dwf Attachments pc: See Page Three
Dr. J. Nelson Grace Limitorque Motor Operators Page Three August 25,1986 pc:
O. W. Dixon, Jr./T. C. Nichols, J r.
E. H. Crews, Jr.
E. C. Roberts O. S. Bradham D. R. Moore J. G. Con nelly, J r.
W. A. Williams, Jr.
i Group Managers W. R. Beeh r C. A. Pri19 W. T. Frady(NSRC)
C. L. Ligon R. M. Campbell, Jr.
K. E. Nodland R. A.Stough G. O. Percival R. L. Prevatte J. B. Knotts, J r.
I&E Washington NPCF File
.M l
4 August 22,1986 JUSTIFICATION FOR CONTINUED OPERATION OF V. C. SUMMER NUCLEAR STATION ~
An Engineering evaluation has been performed to justify continued operation of V. C. Summer Nuclear Station until Limitorque motor operated valves have been inspected prior to or during the next refueling, scheduled for the second quarter of 1987. This evaluation considered environmental conditions and operations during accident conditions. Failure modes and spurious operations due to control wire insulation failure and " hot shorts" were also evaluated.
Based on preliminary in-house testing and engineering judgement, the wire of the type found in SCE&G Limitorque valves is acceptable at temperatures up to 220 F l
for the duration required for outside containment use. Therefore, for this evaluation the installed wire is concluded to be acceptable for use through Refueling 3 for areas which do not go beyond 220 F. Radiation exposure outside containment in post accident conditions will not produce an integrated dose considered to be a major concern for operation of the valves. No significant degradation of control wire insulation is expected for total integrated dose less than 10E7 Rads.
1 The valves considered in this evaluation were selected based on a review of FSAR I
Tables 3.11-0, NSSS Class IE Equipment, and 3.11-0A, BOP Class 1E Equipment, a review of the 302 series Syst,em Flow Diagrams and Emergency Operating Procedures. The following is the summary of operators evaluated:
Reference Tv 3e Location Number of Valves FSAR Table 3.11-0 NSSS C ass 1E In Containment S
FSAR Table 3.11-0 NSSS Class 1E Outside Containment 43 i
FSAR Table 3.11-0 Class 1E in Containment 3
Special Q-list items i
FSAR Table 3.11-0A BOP 1E in Containment 5
FSAR Table 3.11-0A BOP 1E Outside Containment 56 Other Valves Misc.
Inside Containment 11 Considered Other Valves Misc.
Outside Containment 8
Considered Totalin Containment 24 Total Outside Containment 107 TotalValves 131 See Attachments I-Vil for the list of valves considered in this evaluation. Postulated Environmental conditions are described in FSAR Table 3.11-3. Several groups of valves were justified because these valves fall into several categories. The summary definitions of categories are as follows:
J 1
Cateaory Definition A1 Equipment that could experience the environmental conditions of Design Bas,is (LOCA) accidents for which it must function to mitigate said accidents is qualified to demonstrate operability in the accident environment for the time required for accident mitigation with safety margin to failure.
A2 Equipment that could experience the environmental conditions of design basis line break accidents, including main steam line break and other line breaks, for which it must function to mitigate said accidents and that is qualified to demonstrate operability in the accident environment for the time required for accident mitigation with safety margin to failure.
A1* Equipment that could ex serience increased radiation exposure due to Post-LOCA recirculation for which it must function to mitigate said accidents and that is qualified to demonstrate operability in the radiation environment for the time required for accident mitigation with safety margin to failure.
B1 Equipment that could experience environmental conditions of design basis (LOCA) accidents through which it need not function for mitigation of said accident, but through which it must not fail in a manner detrimental to plant l
safety or accident mitigation, and that is qualified to demonstrate the capability to withstand any accident environment for the time during which it j
must not fail with safety margin to failure.
B2 Equipment that could experience environmental conditions of design basis line break accidents, including main steam line break and other line breaks, through which it need not function for mitigation of said accidents, but through which it must not fail in a manner detrimental to plant safety or i
accident mitigation, and that is qualified to demonstrate t be capability to withstand any accident environment for the time during which it must not fail with safety margin to failure.
B1* Equi 3 ment that could experience increased radiation exposure due to post-accic ent recirculation through which it need not function for mitigation of said accidents, but through which it must not fail in a manner detnmental to plant safety or accident mitigation, and that is qualified to demonstrate the capability to withstand any radiation environment for the time during which it must not fail with safety margin to failure.
C1 Equi ament that could experience environmental conditions of design (LOCA) accic ents through which it need not function for mitigation of said accidents, and whose failure (in any mode) is deemed not detrimental to plant safety or i
accident mitigation, and need not be qualified for any accident environment, but is qualified for the nonaccident service environment.
l C2 Equipment that could experience environmental conditions of design basis line break accidents, including main steam line break and other line breaks, through which it need not function for mitigation of said accidents, and whose failure (in any mode)is deemed not detrimental to plant safety or accident mitigation, and need not be qualified for any accident environment, j
but is qualified for the nonaccident service environment.
2
Category Definition D
Equipment that would not experience environmental conditions of design basis accidents and thatwill be c ualified to demonstrate operability in t1e normal and abnormal service environment. This equipment is located outside containment.
The following are summaries of evaluations used to justify continued operation untilinspection of the evaluated valves. The attachments contain a column that matches the valve to the justification to be applied:
i l
Justification Number Justification 1
Valves listed as Category A1*, B1*, and D in Tables 3.11.0 and i
3.11.0a are not subject to high temperature environment and.
are located outside containment where the integrated radiation doses will not be excessive for the analysis event j
l until well into Post LOCA Recirculation. Valves listed as C1 and C2 need not function for mitigation of said accident I
whose failure in any mode is deemed not detrimental to plant safety or accident mitigation.
FSAR Table 3.11-0 contained 40 valves outside containment listed as A1* and C2. Additionally, Table 3.11-0A lists 42 valves outside containment that are enveloped by A1*, B1*,
D, C1 and C2.
2 The remaining 3 valves outside containment listed on 3.11-0 (8109 A, B & C-CS) are B1 and C2. The B1 environment for these valves is significantly less than 220 F. The C2 condition has been justified above in justification number 1.
10 additional BOP valves outside containment (95268-CC, 96878-CC,1001 A & B-EF,1037A & B-EF,1002-EF,1008-EF, 3103 A-SW and 3107 A-SW) are located in areas which do not
]
experience an environment over 220 F.
3 11 valves (8701 A & B-RH,8702 A & B-RH,8808 A, B & C-SI, 8095 A & B-RC and 8096 A & B-RC) normally have their power removed. These valves are all located in containment. They are not automatic valves and their failure would be recognized when attempting to cycle the valve. A guideline is available to the operators, GOP-8 Attachment XVil, for remote operation of motor operated valves at the motor control centers. This guideline provides guidance to the operator to remove the valve control power and to operate it l
by mechanically actuating the appropriate contactor while monitoring the valve current, therefore eliminating any i
3
- l..
i justification Number Justification problems associated with Limitorque supplied wiring (e.g.,
opens, shorts, hot shorts).
4 8 Reactor Building Cooling Unit Service Water isolation valves (3108 A, B, C & D-SW and 3109 A, B, C & D-SW) are not required to change position for accidents. These could be of concern if they inadvertently cycled during an accident.
i Spurious operation due to hot shorts will be eliminated as a concern by removing power to the valve operator. A valve could be operated per GOP-8 Attachment XVilif required.
5 4 valves outside containment subject to steam break environment,9526 A-CC,9687 A-CC and 2802 A & B-MS have been inspected and presently contain acceptable wire.
6 The three pressurizer PORV block valves 8000 A, B & C-RC are s secial Q-List valves that are not required to be operable o uring accident condition and receive no automatic signals.
Their function is to isolate a potential, stuck pressurizer t
PORV. If a PORV can not be isolated it is bounded by the FSAR LOCA analysis. Additionally, two of these valves are presently closed with power removed.
7 Valve 9605-CC is a component cooling valve inside containment. It is required to close on containment phase B isolation. The component cooling system is a code class piping system. This valve is in series with valve 9606-CC which is accessible during a LOCA.
Valve 8112-CS is a reactor coolant pump seal return valve inside containment. It is required to close to prevent loss of RCS inventory or seal injection. This valve is in series with valve 8100-CS which is outside containment and accessible j
during a LOCA.
Operations has been instructed to verify 8100-CS and 9606-CC closed in accident conditions which require their closure.
Operations will verify each valve closed while simultaneously removinc' power to the operator. If they will not close electricaI y they are accessible and may be closed locally.
i The questionable valves inside containment 8112-CS and 9605-CC will initially be functional and should stroke to their required position upon reciept of the appropriate Phase A or Phase B containment isolation signal. To preclude spurious re-opening, Operations will verify each valve closed while i
simultaneously removing power to the operator. If these i
i 4
Justification Number Justification valves can not be verified closed, they shall be closed utilizing GOP-8 Attachment XVil.
8 These 5 valves (6516-VU,6517-VU,6518-VU,6519-VU and 8105-CS) are located in areas which do not experience an environment over 220 F.
9 These 3 valves (1689 A, B & C-FW) normally have power removed to the operator and therefore are not subject to spurious valve operation. They are closed and are not required for any accident conditions.
Based on this engineering evaluation and the list of required actions that need to be taken, it is concluded that continued operation of V. C. Summer Nuclear Station until the wiring inspection and replacement program can be completed isjustified and will not adversely impact public health and safety.
1 l
i l
1 5
1 r
ep-
-w--
l ATTACHMENT I NUCLEAR STEAM SUPPLY SYSTEM CLASS lE LIMITORQUES IN CONTAINMENT (REF. FSAR TABLE 3.11-0)
JUST F AT ON EQUIPMENT CATEGORY LOCATION 8112-CS Al, C2 Reactor Building 7
8701 A,B-RH Al, C2 Reactor Building 3
j 8702 A,B-RH i
j ATTACHMENT 11 NUCLEAR STEAM SUPPLY SYSTEM CLASS lE LIMITORQUES OUTSIDE CONTAINMENT (REF. FSAR TABLE 3.11-0) 3UST F T ON EQUIPMENT CATEGORY LOCATION N
8100-CS Al*,C2 West Penetration Access Area 1
LCV-115 C,E-CS Al*,C2 Auxiliary Building 1
LCV-115 B,D-CS Al*,C2 Auxiliary Building 1
8102A-CS Al*,C2 West Penetration Access Area 1
8102B,C-CS East Penetration Access Area 1
i 8104-CS Al*,C2 Auxiliary Building 1
8109 A,B,C-CS, Bl, C2 Auxiliary Building 2
8130 A,B-CS, Al*,C2 Auxiliary Building 1
8131 A,B-CS, Auxiliary Building 1
8706 A,B-RH 8132 A,B-CS, Al*,C2 Auxiliary Building 1
8133 A,B-CS 8106-CS Al*,C2 Auxiliary Building, 1
8107-CS,8108-CS, West Penetration Access Area 1
8884-51,8885-51, 8886-51 FCV-602 A,B-RH Al*,C2 Auxiliary Building 1
8801 A,B-SI, Al*,C2 Fuel Handling Building 1
8803 A,B-Sl#
8809 A,B-Sl; 8811 A,8-Sl; Al*,C2 Auxiliary Building 1
8812 A,B-SI 8887 A,B-SI Al*,C2 West Penetration Access Area 1
88888-51,8888A-SI, Al*,C2 East Penetration Access Area 1
8889-51 West Penetration Access Area 1
- NOTE -8803 A AND B HAVE BEEN REMOVED FROM THE PLANT
I ATTACHMENTlli NUCLEAR STEAM SUPPLY SYSTEM CLASS lE EQUIPMENT IN CONTAINMENT SPECIAL Q-LIST ITEMS (REF. FSAR TABLE 3.11-0)
JUST F AT ON EQUIPMENT LOCATION 8000A-RC Reactor Building 6
8000B-RC Reactor Building 6
8000C-RC Reactor Building 6
l
ATTACHMENT IV BALANCE OF PLANT CLASS IE EQUIPMENT IN CONTAINMENT (REF. FSAR TABLE 3.11-0A)
NS F A EQUIPMENT CATEGORY LOCATION N
gE XVG9605-CC Al, C2 Reactor Building 7
XVT8095A-RC A1,C2 Reactor Building 3
XVT80958-RC A1,C2 Reactor Building 3
XVT-8096A-RC A1,C2 Reactor Building 3
XVT-8096B-RC A1,C2 Reactor Building 3
~
ATTACHMENT V BALANCE OF PLANT CLASS lE EQUIPMENT OUTSIDE CONTAINMENT (REF. FSAR TABLE 3.11-0A)
LUST F AT ON i
EQUIPMENT CATEGORY LOCATION N
XVG2802A-MS B2 East Penetration Access Area 5
XVG28028-MS B2 East Penetration Access Area 5
XVG9568-CC Al*,C2 West Penetration Access Area 1
XVG9606-CC Al *, C2 West Penetration Access Area 1
XVG9600-CC C2 East Penetration Access Area 1
XVG9625-CC C2 Auxiliary Building 1
XVG9626-CC C2 Auxiliary Building 1
XVB95268-CC A2 Intermediate Building 2
XVB96878-CC A2 Intermediate Building 2
XVB9526A-CC A2 Intermediate Building 5
i XVB9687A-CC A2 Intermediate Building 5
XVB9503A-CC Al*,C2 Auxiliary Building 1
XVB95038-CC A1*,C2 Auxiliary Building 1
XVB9524A-CC C2 Auxiliary Building 1
XVB95248 CC C2 Auxiliary Building 1
XVB9525A-CC C2 Auxiliary Building 1
l XVB95258-CC C2 Auxiliary Building 1
1 XVG1001 A-EF A2 Intermediate Building 2
XVG10018-EF A2 Intermediate Building 2
XVG1002-EF A2 Intermediate Building 2
XVG1008 EF A2 Intermediate Building 2
XVG1037A-EF A2 Intermediate Building 2
XVG1037B-EF A2 Intermediate Building 2
XVG6797-FS C2 West Penetration Access Area 1
XVT1633A-FW Al *, C2 West Penetration Access Area 1
XVT1633B-FW C2 East Penetration Access Area 1
XVT1633C-FW C2 East Penetration Access Area 1
XVG3003A-SP A1 *, C2 West Penetration Access Area 1
XVG30038-SP Al *, C2 West Penetration Access Area 1
XVG3001 A-SP Al*,C2 Auxiliary Building 1
i XVG3001B SP A1 *, C2 Auxiliary Building 1
i
ATTACHMENT V BALANCE OF PLANT CLASS lE EQUIPMENT OUTSIDE CONTAINMENT (REF. FSAR TABLE 3.11-0A)
NST
^
EQUIPMENT CATEGORY LOCATION N
BE XVG3002A-SP Al*,C2 Auxiliary Building 1
XVG3002B-SP A1*,C2 Auxiliary Building 1
XVG3004A-SP A1*,C2 Auxiliary Building 1
XVG30048-SP Al*,C2 Auxiliary Building 1
XVG3005A-SP A1*,C2 Auxiliary Building 1
XVG3005B-SP A1*,C2 Auxiliary Building 1
XVB3126A D
Intermediate Building 1
XVB3126B D
Intermediate Building 1
XVB3128A D
Intermediate Building 1
(
XVB3128B #
D Intermediate Building 1
XVB3128C D
Intermediate Building 1
XVG3103A-SW A1*,B2 West Penetration Access Area 2
i XVG3107A-SW Al*,B2 West Penetration Access Area 2
XVG3111 A-SW Al*,C2 West Penetration Access Area 1
XVG3112A-SW A1*,C2 West Penetration Access Area 1
XVG31038-SW D
Fuel Handling Building 1
XVG3107B-SW D
Fuel Handling Building 1
XVG31118-SW D
Fuel Handling Building 1
XVG3112B-SW D
Fuel Handling Building 1
XVB3106A-SW A1*,C2 West Penetration Access Area 1
j XVB3110A-SW A1*,C2 West Penetration Access Area 1
XVB3106B-SW D
Fuel Handling Building 1
i XVB31108-SW D
Fuel Handling Building 1
XVB311GA-SW D
Service Water Pump House 1
XVB3116B-SW D
Service Water Pump House 1
XVB3116C-SW D
Service Water Pump House 1
- NOTE - VALVE 3128B is listed incorrectly in Table 3.11-QA. It is a manual valve.
h g
ATTACH M ENT VI -
OTHER VALVES CONSIDERED DUE TO POTENTIAL FOR SPURIOUS OPERATION IN CONTAINMENT JUSTlFICATION EQUIPMENT NUMBER 3108 A-SW 4
3108 B-SW 4
3108 C-SW 4
3108 D-SW 4
3109 A-SW 4
3109 B-SW 4
3109 C-SW 4
I 3109 D-SW 4
8808 A-Si 3
8808 B-SI 3
8808 C-SI 3
e l
i.
l l
r
)
i
..r-,-,.--v-
,v.,
o ATTACHMENT Vil OTHER VALVES CONSIDERED 1E BUT NOT LISTED IN FSAR AS 1E OUTSIDE CONTAINMENT EQUIPMENT JUSTIFICATION NUMBER 1689 A-FW #
9 1689 B-FW #
9 1689 C-FW #
9 6516-VU 8
6517-VU 8
6518-VU 8
6519-VU 8
8105-CS 8
- NOTE --Valves bought as 1E but not implemented 1E in the plant.