ML20045B085
| ML20045B085 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 06/09/1993 |
| From: | Storz L CENTERIOR ENERGY |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 2150, IEB-93-002, IEB-93-2, NUDOCS 9306160245 | |
| Download: ML20045B085 (4) | |
Text
_.
~
CENTERDOR ENERGY 6200 Dok Tree Boulevard Mail Address independence OH PO Box 94661 716-447-310 0 Clevetand. 0H 4410b4661 Docket Number 50-346 License Number NPP-3 Serial Number 2150 June 9, 1993 United States Nuclear Regulatory Commission Document Control Desk Vashington, D. C.
20555
Subject:
Response to NRC Bulletin No. 93-02, Debris Plugging Of Emergency Core Cooling Suction Strainers Gentlemen:
Pursuant to 10 CFR 50.54(f) the following is Toledo Edison's response to NRC Bulletin 93-02, Debris Plugging of Emergency Core Cooling Suction Strainers.
The subject bulletin requested that Toledo Edison (TE) determine whether fibrous air filters or other temporary sources of fibrous material, not designed to withstand a Loss of Coolant Accident (LOCA),
are installed or stored in the Davis-Besse Nuclear Power Station (DBNPS) containment vessel.
If such material exists in containment, TE is required to-remove the material at the next shutdown, or within 120 days, whichever comes first.
Toledo Edison Remedial Action Engineering, Radiation Protection, Maintenance, and Operations personnel performed system and program reviews for permanent or temporary equipment and items located in containment to determine the potential existence of fibrous material. The-review confirmed that there is no source of permanent or temporary material in the DBNPS containment that could plug the Containment Emergency Sump racks or
. screens to prevent the Emergency Core Cooling Systems (ECCS) from performing their design function following a LOCA. The containment suction for the ECCS are located in the Containment Emergency Sump.
In addition, on May 21, 1993 vith the plant shut down,.a containment valkdown was performed and confirmed that no fibrous material or other source of material capable of plugging the Containment Emergency Sump is installed or stored in the DENPS containment.
//
Opeong Companies:
1500t a
/
l c
and Dectnc muminomo 9306160245 930609 R
PDR ADDCK 05000346 h
v 0
PDR g
.=
2 Docket Number 50-346
~* -
License Number NPF-3
-Serial Number 2150
[
Page 2 Toledo Edison Existing Controls j
Davis-Besse Technical Specifications 4.5.2 and 4.5.3 contain requirements intended to assure that no foreign debris can be transported to the containment emergency sump thereby causing restriction of the pump suctions. These requirements are implemented by the following procedures:
3 1.
Surveillance procedure DB-SP-03134, Containment Emergency Sump
+
Visual Inspection, requires the Containment Emergency Sump be j
visually inspected at least once per 18 months to ensure that the ECCS suction inlets are not restricted by debris (trash, rags, clothing, etc.) and the sump components (trash racks, screens, etc.) show no evidence of structural distress or corrosion.
j 2.
The DBNPS Plant Heatup procedure, DB-0P-06900, requires that i
Maintenance, Operations, and Radiation Protection personnel perform tours of containment to verify that no loose debris is present which could be transported to the Containment Emergency Sump.
l 3.
The DBNPS Plant Startup procedure, DB-0P-06901, requires that l
Radiation Protection and Operations personnel perform an additional containment tour prior to entering Mode 2.
Toledo Edison Planned Action Toledo Edison vill perform the following actions to ensure fibrous j
material vill not plug the ECCS suction strainers during a LOCA:
.{
l.
DB-0P-06900, Plant Heatup, and DB-0P-06901, Plant Startup, will be revised to specifically include inspections for sources'of fibrous material in containment.
2.
The Toledo Edison Design Criteria Manual (DCM)-vill be revised to l
ensure that new equipment considered for installation in i
containment-is evaluated for potentially plugging the ECCS suctions vith fibrous material.
The existing administrative controls have been~ demonstrated to be effective in providing reasonable assurance that the ECCS will not be i
degraded by foreign debris. These controls plus the enhancements identified vill improve this assurance.
i i
l i
i i
i b
e
' Docket Number 50-346 License Number NPF-3 Serial Number 2150
-Page 3 If you have any questions concerning this matter, please' contact Mr. R. W. Schrauder, Manager - Nuclear Licensing, at (419) 249-2366.
Very truly yours,
.- )k 2
L. F. Storz Vice President - uclear KAF/dle Enclosure cc:
J. B. Hopkins, NRC/NRR DB-1 Senior Project Manager J. B. Martin, Regional Administrator, NRC Region III S. Stasek, NRC Senior Resident Inspector Utility Radiological Safety Board t
r v
l
-- J
- s Docket Number 50-346 License Number NPF-3 Serial Number 2150 Enclosure
-Page 1
- 1%57:q Response to NRC Bulletin Number 93-02 for Davis-Besse Nuclear Power Station Unit Number 1 This letter is submitted in conformance with Atomic Energy Act of 1954 Section 182a as amended and 10CFR50.54(f), in response to NRC Dulletin 93-02 (Log Number 1-2846), " Debris Plugging of Emergency Core Cooling Suction Strainers."
By:
L. F. Storz, Vice Presi@pt' - Nuclear Svorn and subscribed before me this 9th day of June, 1993.
1 (L?ktJ Y <b]A$Y Notary PubYic, State of Ohio EVELYNL DPE.SS MX,'JWPUBLE,STAE CF OMO 14hm Epu.th 23,tirA