ML20045B310
| ML20045B310 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 06/10/1993 |
| From: | Schnell D UNION ELECTRIC CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| IEB-93-002, IEB-93-2, ULNRC-2811, NUDOCS 9306170173 | |
| Download: ML20045B310 (5) | |
Text
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1931Dxteaa Avenue.
Pm C*irce By 149
. St Louis IAucun 63165 314 554 2650 DonaldF. Schnell.
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- Senior Vice Pmudent '
hRLECTIUC uvow
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June 10, 1993 p
U.S. Nuclear Regulatory Commission Attn:
Document Control Desk Mail Station F1-137 Washington, D.C. 20555 Gentlemen:
ULNRC. 2811 DOCKET NUMBER 50-483 CALLAWAY PLANT DEBRIS PLUGGING OF EMERGENCY CORE COOLING SUCTION STRAINERS
Reference:
NRC Bulletin No. 93-02, dated May 11, 1993 NRC Bulletin No. 93-02.-requested Licensees to identify fibrous air filters or other temporary sources of fibrous material, not designed to withstand a'LOCA, which are installed.or. stored in primary. containment.
If any of the subject: material is-installed:or. stored in containment, take any-immediate compensatory.-
measures.which may be required to assure functional.
capability of'the ECCS and: provide'a schedule for removal of any such material.
A description of the Callaway Plant containment recirculation sump design is contained'in Section 6.2.2.1.'2.2 of the Callaway Final Safety.
Analysis Report..The sumps are located as far as
~
feasible from reactor coolant: system piping and.
components.which could-become' sources of debris.
The majority. of thermal insulation' is ~ either reflective insulation, which is not a fibrous material, or NUKON, which.is encased in sheet metal and prevents insulation damage and precludes migration to the sumps.
The; sumps are: designed with three~ levels of screening from~a course mesh to a fine wire mesh screening. ' Debris; generated as.a resultLof a LOCA'will
.either be retained-in an area such as the reactor cavity or refueling pool, or-must' follow a tortuous:
I'
, path.to reach the recirculation sump screens.
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addition, the screens have been sized per Regulatory Guide 1.82, assuming 50 percent blockage.
Callaway Plant has prefilters installed in the Containment Atmospheric Control Units (FGR01A/B),
however, they are a fierous material not susceptible to water degradation.
The filters were supplied by Mine Safety Appliances and are a moisture resistant glass mat filter.
These filters are enclosed in a rigid metal enclosure.
Although the filter inlet opening is not enclosed, the integrity of the filter material and rigid enclosure casing would preclude any significant fibrous material migration.
No fibrous material is stored in containment during plant operation.
Any requests for storage of material in containment are procedurally controlled and an evaluation is performed to assess the potential for blocking the containment sumps.
Callaway Technical Specification 4.5.2 requires visual inspection of the containment sumps for debris, structural distress or abnormal corrosion on a 18 month frequency.
This Specification also requires that the containment be inspected for loose debris prior to each time containment integrity is established and also each time a containment entry is made during power operations.
Based on the above information, no additional compensatory measures are'necessary.
If you have any questions concerning this matter, please contact us.
Ve truly yours, i
Donald F.
Schnell JMC/DS/plh
STATE OF MISSOURI
)
)
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Donald F.
Schnell, of lawful age, being first duly sworn upon oath says that he is Senior Vice President-Nuclear and an officer of Union Electric Company; that he has read the foregoing document and knows the content thereof; that he has executed the same for and on behalf of said company with full power and authority to do so; and that the facts therein stated are true and correct to the best of his knowledge, information and belief.
0-By Donald F.
Schnell Senior Vice President Nuclear SUBSCRIBED and sworn to before me this /8
- day of Ow.rt e-1993.
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tGI ARY f%t.lC-STATE OP MISSOURI Mf CWMISSION E.XP!RES AFRll'22,19?nl SI. LOUIS CoutuX
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P cc:
T. A.
Baxter, Esq.
i Shaw, Pittman, Potts & Trowbridge 2300 N.
Street, N.W.
Washington, D.C.
20037 Dr. J.
O.
Cermak CFA, Inc.
18225-A Flower Hill Way l
Gaithersburg, MD 20879-5334 L. Robert Greger Chief, Reactor Project Branch 1 U.S.
Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen.Ellyn, Illinois 60137 i
Bruce Bartlett Callaway Resident Office U.S.
Nuclear Regulatory Commission RR#1 Steedman, Missouri 65077 L.
R. Wharton (2) l Office of Nuclear Reactor Regulation U.S.
Nuclear Regulatory Commission 1 White Flint, North, Mail Stop 13E21 11555 Rockville Pike Rockville, MD 20852 Manager, Electric Department Missouri Public Service Commission P.O.
Box 360 Jefferson City, MO 65102 i
bec:
D. Shafer/A160.761
/QA Record (CA-758)
Nuclear Date E210.01 DFS/ Chrono D.
F.
Schnell J.
E.
Birk J. V.
Laux M. A.
Stiller G.
L. Randolph R.
J.
Irwin P.
Barrett C.
D. Naslund W.
R.
Campbell A.
C.
Passwater D.
E.
Shafer W.
E. Kahl S.
Wideman ( WCNOC)
M. D. Archdeacon (Bechtel)
S.
E.
Sampson NSRB (Sandra Dale) 9