ML20008D795
| ML20008D795 | |
| Person / Time | |
|---|---|
| Site: | Dresden, Byron, Braidwood, Quad Cities, Zion, LaSalle, 05000000 |
| Issue date: | 08/08/1978 |
| From: | Reed C COMMONWEALTH EDISON CO. |
| To: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| Shared Package | |
| ML20008D796 | List: |
| References | |
| FOIA-89-404 IEB-78-10, NUDOCS 8009160653 | |
| Download: ML20008D795 (10) | |
Text
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August 8, 1978 J
I Mr. James 0. Keppler, Director Directorate of Inspeittion and l
Enforcement - Regicn III U.S. Nuclear Regulato. y Conssission 799 Roosevelt Road Glen Ellyn, Illinois 60137
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Subject:
Dresden Station Uni.O 1, 2 and 3 Quad-Cities Station Units 1 and 2 Zion Station Units 1 and 2 LaSalle County Station Units 1 and 2 l
Byron Station Units 1 and 2 Braidwood Station Units 1 and 2 Response to IE B No. 78-10 l
NRC Docket Nos__50 1 37/249, i
i 50-254/265, 50-295/304, 50-373/374 i
and 50-454/455/456/437 l
Reference (a) :
J. G. Keppler letter to B. Lee, Jr.
dated June 27, 1978
Dear Mr. Keppler:
Reference (a) transmitted IE Bulletin No[ 78-10 concerning Bergen-Paterson hydraulic shock suppressor accumulator spring coils.
Enclosed is commonwealth Edison's response to this bulletin for Dresden Station Units 1, 2 & 3, Quad-cities Station Units 1 & 2, Zion Station Units 1 & 2, LaSalle County Station Units 1 & 2, Byron Station Units 1 & 2 and Braidwood Station Units 1 & 2.
L Please address any questions concerning this matter to this office.
Very truly yours, l
I MAordell Reed Assistant Vice-President enclosure Director, Division of cc:
Reactor Operations Inspection AUG 101978 y
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mh Commonwealth EdlCn HM Docket H s. 50-10 50-237
$NCLOSVRE 50-249
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DRESDEN STATION UNITS 1, 2 AND 3
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i A review of the records for safety-related Bergen-Paterson snubbers with steel accumulator springs was performed
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at Dresden Station.
No Bergen-Paterson snubbers are installed on Dresden Unit 1 While a complete visual verification of i
all snubbers cannot be made during unit operations, records l
indicate-there are a number of safety-related torus, drywell, 1
and spara snubbers (see attachments) that are apparently equipped with the carbon steel springs.
Two hydraulic anubbers installed on the torus for Dresden Unit 3 have carbon steel springs.
Pending the i
availability of replacement parts, those springs will be replaced with teflon coated or stainless steel springs before the end of the unit's next refueling outage.
Also, replacement accumulator nprings will be installed in spare hydraulic anubbers when replacement parts are obtained.
We have already initiated a program to replace all safety-related Bergen-Paterson hydraulic snubbers installed inside Units 2 and 3 drywell with pacific Scientific company mechanical snubbers.
Ten out of the thirty-five drywell hydraulic snubbers on Unit 3 have already been replaced with mechanical snubbers.
The remaining safety-related. hydraulic anubbers are scheduled to be replaced during the next two refueling outages.
Dresden Station has not experienced any accumulator spring f ailures to date.
As IE Bulletin No. 78-10 points out, the failure of the spring does not by itself make the snubber inoperable, and we believe the probability is small that it might indirectly result in snubber inoperability.
Therefore, it is not believed the expense and radiation exposure associated with accelerating our replacement program is justified.
Accordingly, we propose to continue our program to replace the safety-related Bergen-Paterson hydraulic snubbers on Dresden j
Units 2 and 3 over the next two refueling outages for each unit.
If unforseen difficulties prevent completion of the replacement program, we will alternatively replace the carbon steel springs with acceptable springs in any remaining Bergen-Paterson snubbers.
In addition we will replace the accumulator springs in any hydraulic snubbers which may be re-installed in the drywell af ter bench testing or maintenance, again depending on the availability of replacement springs.
Commonweenh E8666R 'Nac poenarm<av.
50-237
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'i-ERICLOSURE b-50-249 4
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The NRC will be informed of any broken springs when the replacement program has been completed.
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Conwnensre:Mh ECoen WRC Dockot N3.
50-237
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ATTACIMENT l
PRESDEN STATIOM J
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1 UNIT 2 B-P Hydraulic Snubber Location and Number Drwell Torus Snubber Actuator Snubber 1,oc. No.
Serial No.
Cyl. Site System Loc. No.
Serial No..
1 487781 HSSA30 Rectre.
4 2
487768 HSSA30 Recire.
2 470000*
3 487814 MSSA30 Recire 3
470013*
4 470014*
4 487762 HSSA30 Recirc.
5 487757 HSSA30 Recirc.
5 469996*
1 6
487758 HSSA30 Recire.
7 487695 USSA30 Recire.
7 470010*
8 487759 RSSA30 Recire.
8 470002*
9 487769 HSSA30 Recire.
9 470007*
10 487791 RSSA30 Recire.
10 469998*
i 11 487787 HSSA30 Recire.
12 487776 HSSA30 Recirc 12 470005*
13 487616 HSSA20 Recire.
13 G39778-02-45*
14 487616
- HSSA20 Recire.
15 replaced LPCI 15 469995*
16 replaced LPCI 16 560603*
17.
482597*
HSSA10 Recire.
3 r
18 replaced HPCI i
19 replaced HPCI 20-replaced HPCI
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21 482596 HSSA10 Recire.
22 replaced HPCI
-23 replaced cleanup 24 487570 HSSA10 F.W.
i 25 replaced cleanup 1
Commonwealm Essen m -m - -
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DRESDEN STAT {0tf UNIT 2" B-P Hydraulic Snubber' Location and Number Drywell l
Snubber Actuator Loc. No.
Serial Not ev1. Size System t
26 replaced F.W.
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27 487554 HSSA10 cle anup 28 replaced F.W.
29 487539 HSSA10 HPCI i
30 487500 HSSA10 c.S.
31 487508 HSSA10 C.S.
l 32 Unknown HSSA30 MSL i
33 Unknown HSSA30 MSL 34 Unknown HSSA20 MSL l
35 Unknown HSSA20 MSL P
-NOTE:
- 1) Drywell info. from maintenance records.
Torus information from inspection, 7/1/78.
Torus snubbers are model HSSA20.
- 2) " REPLACED" notation indicates that snubber is presently a mechanical snubber manufactured by Pacific Scientific Co.
- Spring replacement not necessary
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DRESDEN STATION.
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f UNIT 3 l
B-P Hydraulic Snubber Location and Number Drywell Torus Snubber Actuator Snubber Loc. No.
Seriel No.
Cyl. Site System,g Loc. No..
Serial No, 1
HSSA30 Recire.
2 487768 HSSA30 Recire.
i' 51035*
i 3
487768 HSSA30 Recire.
3 51035*
4 487762 HSSA30 Recire.
4 51035*
5 487757 HSSA30 Recire.
5 51035*
6 487758 HSSA30 Recire.
7 487695 HSSA30 Recire.
7 51035*
8 487759 HSSA30 Recire.
8 51035*
9 487769 HSSA30 Recire.
9 51035*
10 487791 HSSA30 Recire.
10 51035*
11 487787 MSSA30 Recire.
12 487776 HsSA30 Rectre.
12 51035*
13 487617 HSSA20 Recirc.
13 51035' 14 487616 HSSA20 Recire.
15 replaced LPCI 15 487617 16 replaced LPCI
' 16 487616 17 482597*
HSSA10 Recire.
18 replaced HPCI 19 replaced HPCI 20 replaced HPCI 21 482596*
HSSA10 Recire.
22 487541 HSSA10 HPCI 23 replaced cleanup 24 replaced F.W.
25 replaced cleanup 26 replaced F.W 27 487554 HSSA10 Cleanup
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28 replaced F.W.
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29 replaced HPCI 30 replaced c.S.
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j3 Commonwethh Edison NRC Docket N3. 50-249
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hTTACRMENT r,;
i WIT 3 B-P Hydraulic Snubber Location and Humber I
Drwell Snubber Actuator l
Loc. No.
Serial No.
Cyl. Size Systems t
31 replaced c.S.
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32 unkno'4n HSSA30 MSL 33 unknwn HSSA20 MSL 34 unknown replaced MSL 35 -
unknwn replaced MSL t
NOTE:
- 1) Drywell info. from maintenance records.
Torus information
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from inspection, 7/1/78.
Torus snubbers are model HSSA20.
- 2) REPLACED" notations indicates that snubbir is presently I
a inechanical snubber manufactured by Pacific Scientific Co.
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- Spring replacement not necessary l
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Commonweemrs......
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S0-249 l
',e ATTAC MINT pkESDEN STATION WITS' t &(.
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- B-P Safety Related Snubbers l
i Model No.
Serial No.
HSSA30 487695 i
HSSA30 487814 i
HSSA30 487762 HSSA10 487556 HSSA10 487511 HSSA10 487541 l
HSSA10 487553 I
HSSA10 487570 t
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Located on 3rd Floor of Rx Bldg. Center in Stores Locker O
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50-265 I
ENCLOSURE e
QUAD-CITIES STATION UNITS 1 AND 2 l
A review of Bergen-Paterson snubbers has disclosed that some of the snubbers installed in safety-related rystems in the drywell have carbon steel spring coils.
It is not possible at this time to determine exactly where these particular snubbers are installed because there is no cross reference of the serial numbers to their exact locations.
The station is presently following a preventative maintenance program of periodically testing the snubbers for operability during each refueling.
At this time the spring coils will be examined and replaced with the teflon coated springs, as necessary.
In the event it is necessary to overhaul a snubber during routine inspections, the accumulator spring coil will be replaced.
Also, modifications are in progress to replace the hydraulic anubbers with mechanical anubbers.
The NRC will be informed of any broken springs when the replacement program has been completed.
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50-373/374-
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50-454/455
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ENCZ4SURE 50-456/457 3)
.y; EION STATION UNITS 1 & 2 IASALLE COUNTY STATION UNITS 1 & 2 BYRON STATION UNITS 1 & 2 BRAIDLf00D STATI,0N UNITS 1 & 2
-A review'of Zion, LaSalle County, Byron and Braidwood Stations: indicate tht no Bergen-Paterson snubbers are installed or in ready. spares.
Therefore, based on this 'eview, we believe r
no further action is necessary.
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