ML20149M727
| ML20149M727 | |
| Person / Time | |
|---|---|
| Site: | Byron, Braidwood, Zion, LaSalle File:ZionSolutions icon.png |
| Issue date: | 01/17/1997 |
| From: | Hosemer J COMMONWEALTH EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| GL-92-08, GL-92-8, NUDOCS 9701270122 | |
| Download: ML20149M727 (5) | |
Text
t Commonwralth liliwn Cannp.iny l
14M) Opus Pixe
, 1)ow ners Gros e,11. (W)515 January 17,1997 U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Attention: Document Control Desk l
Subject:
Byron Station Units 1 and 2 Braidwood Station Units 1 and 2 LaSalle County Station Units 1 and 2 Zion Station Units 1 and 2 Status of Actions to Address Generic Letter 92-08, Thermo-Lag 330-1 Fire Barriers NRC Docket Numbers: 50-295.304. 373.
374. 454. 455. 456 and 457
References:
(See Attachment A)
The Commonwealth Edison Company (Comed) is providing the following information as an update to the Nuclear Regulatory Commission (NRC) on the status of the actions to address Generic Letter (GL) 92-08, "Thermo-Lag 330-1 Fire Barriers," for the four Comed nuclear stations to which it applies: Byron, Braidwood, LaSalle and Zion. In December,1993, Comed stated its intention to address and resolve the Thermo-Lag 330-1 issue by the end of 1996. As of December 31,1996, Comed believes resolution of the Thermo-Lag 330-1 issue under GL 92-08 has been achieved, with the completion of the planned actions for each station, as summarized below, i
LaSalle Station:
Consistent with the schedule stated in Reference 1, the Thermo-Lag 330-1 was removed and a repl8 cement fire barrier (Darmatt KM-1) installed as of February l
9,1995. The NRC staff review and acceptance of the Darmatt KM-1 as a one l
hour fire barrier was documented in Reference 5 and the NRC evaluation of the consequences of its postulated failure under a seismic loading was completed in i
Reference 9. Answers to the NRC Staff questions regarding the ampacity derating analyses performed for the LaSalle Darmatt KM-1 installations were provided in Reference 6.
~
g 9701270122 970117 PDR ADOCK 05000295 F
PDR l
I unwom comp.mv
t..
The actions to address the Thermo-Lag 330-1 fire barrier issues for LaSalle have been completed.
Zion Station:
In accordance with the schedule stated in Reference 4, the Thermo-Lag 330-1 installed as a fire barrier on the two Unit 1, one Unit 2 and two Unit common power conduits has been removed and has been replaced with the Darmatt KM-1 fire barrier system. The Thermo-Lag 330-1 installed on the conduit in the Unit 1 auxiliary building stairwell has been removed and replaced with 3M Interam E-50 Series fire barrier material. Also, the partial-height TSI walls separating the turbine and motor driven auxiliary feedwater pumps on Units 1 and 2 have been removed and replaced with walls constructed of Promat-H Board, manufactured by Eternit, Inc., per UL Design No. U523. These installations were complete as of December 30,1995.
The Thermo-Lag 330-1 that is to remain is installed as a radiant energy heat shield, on th.ee inside containment, pressurizer level transmitter signal cables (two in Unit 1 and one in Unit 2). For this installation, a Zion specific exemption request has been prepared and submitted to the NRC staff in Reference 7, consistent with prior NRC staff guidance. The answers to a subsequent NRC Request for Additional Information (RAl) on the exemption request were l
provided to the NRC staff in Reference 13. Also, NRC questions regarding the chemical analysis of the Thermo-Lag 330-1 were answered in Reference 10, where it was confirmed that the Thermo-Lag 330-1 materials used at Zion Station are representative of the population of samples that have been tested by the Nuclear Energy Institute (NEI).
The actions to address the Thermo-Lag 330-1 fire barrier for Zion Station have been completed. Also, this status update provides the confirmation in writing of the status at Zion Station as requested in Reference 12.
Comed is awaiting NRC response to the Zion specific exemption request.
Byron Station:
Reference 2 summarized the revised plan and schedule to address GL 92-08 at Byron Station, where three methods of resolution were utilized:
- 1) Re-analysis of Safe Shutdown Analyses to eliminate the need for the fire
- barrier,
- 2) Re-routing of cables such that redundant safe shutdown trains are not located in the same fire zone, or 2
4
- 3) Replacement of the Thermo-Lag 330-1 with a qualified fire barrier.
In accordance with the plan provided in Reference 2, all planned modifications have been installed. Several safe shutdown cables located in Unit 1, have had the Thermo-Lag 330-1 removed and are now protected with the Darmatt KM-1 fire barrier system. For the remaining safe shutdown cables, they have been re-routed such that the re-routed cables and their corresponding redundant counterparts and associated support equipment cables are not located in the same zone. Since a fire barrier is no longer necessary for these circuits, the Thermo-Lag 330-1 has been abandoned in place.
The Fire Protection Report has been revised to reflect the plant changes. The changes in effect as of June,1996 were submitted to the NRC in Byron /Braidwood Fire Protection Report Amendment #17 on December 16, 1996. The changes in effect after June,1996 will be submitted to the NRC in Byron /Braidwood Fire Protection Report Amendment #18, in December,1997, in accordance with the planned schedule for submitting this amendment. These changes have been evaluated per 10CFR50.59.
NRC questions regarding ampacity derating analyses for both the Thermo-Lag 330-1 and the Darmatt KM-1 install &tions were answered in References 8 and
- 11. The actions to resolve the concerns related to the cable ampacity for the cable routed in raceway wrapped with Thermo-Lag 330-1 listed in Reference 11, have been completed.
The actions to address the Thermo-Lag 330-1 fire barrier for Byron Station have been comp leted.
i Braidwood Station:
Reference 3 summarized the revised plan and schedule to address GL 92-08 at Braidwood Station, where two methods of resolution were utilized:
- 1) Reducing the population of cables requiring protection (Safe Shutdown cables) via engineering analysis, or
- 2) Re-routing of the reduced population of Safe Shutdown cables, such that redundant safe shutdown trains are not located in the same fire zone.
in accordance with the plan provided in Reference 3, all planned modifications at Braidwood Station have been installed. The cables necessary for safe shutdown have been re-routed, such that the re-routed cables and their corresponding redundant counterparts and associated support equipment cables are not located in the same zone. For these circuits, since a fire barrier is no longer necessary, the Thermo-Lag 330-1 has been abandoned in place.
3
... _ _ ~.
l a
l l
The Fire Protection Report has been revised to reflect the plant changes. The changes in affect as of June,1996 were submitted to the NRC in i
Byron /Braidwood Fire Protection Report Amendment #17 on December 16, 1996. The changes in affect after June,1996 will be submitted to the NRC in Byron /Braidwood Fire Protection Report Amendment #18, in December,1997 in accordance with the planned schedule for submitting this amendment. These changes have been evaluated per 10CFR50.59.
NRC questions regarding ampacity derating analyses for both the Thermo-Lag 330-1 installations were answered in References 8 and 11. The actions to j
resolve the concerns related to the cable ampacity for the cable routed in l
raceway wrapped with Thermo-Lag 330-1 listed in Reference 11, have been l
completed.
The actions to address the Thermo-Lag 330-1 fire barrier for Braidwood Station l
have been completed.
l If there are any further questions concerning this mater, please contact Denise l
Saccomando at 630-663-7283.
Sincerely, m8 John B. Hosmer Engineering Vice President l
l Attachment CC:
G. Dick, Byron Project Manager - NRR l
R. Assa, Braidwood Project Manager - NRR l
D. Skay, LaSalle Project Manager - NRR l
C. Shiraki, Zion Project Manager - NRR S. Burgess, Senior Resident inspector - Byron C. Phillips, Senior Resident inspector - Braidwood M. Huber, Senior Resident inspector - LaSalle Co.
A. Vegel, Senior Resident inspector - Zion l
A. B. Beach, Regional Administrator - Rlli l
Office of Nuclear Safety -IDNS 4
l
... _ ~.
,*.V
\\
j 1
=
Attachment A Status of Actions to Address Generic Letter 92-08 Thermo-Lag 330-1 Fire Barriers References 1)
December 13,1994, R. E. Querio letter to USNRC 2)
September 20,1995, K. L. Graesser letter to USNRC t
i 3)
September 25,1995, K. L. Kaup letter to USNRC 4)
October 2,1995, M. J. Vonk letter to USNRC l
5)
November 20,1995, R. M. Latta letter to D. L. Farrar i
6)
December 22,1995, D. M. Saccomando letter to USNRC l
7)
January 11,1996, R. P. Tuetken letter to USNRC 8)
March 21,1996, D. M. Saccomando letter to USNRC 9)
March 29,1996, D. M. Skay letter to D. L. Farrar 10)
July 12,1996, R. P. Tuetken letter to USNRC 11)
July 12,1996, J. B. Hosmer letter to USNRC l
12)
September 5,1996, C. Y. Shiraki letter to 1. Johnson i
13)
November 7,1996, J. H. Mueller letter to USNRC l
l l
5
,