ML20100M680
| ML20100M680 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 11/28/1984 |
| From: | Hufham J TENNESSEE VALLEY AUTHORITY |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| REF-PT21-85-072-000 PT21-85-072-000, NUDOCS 8412120416 | |
| Download: ML20100M680 (2) | |
Text
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-~-TENN pE VALLEY AUTHORITY A 1 L. W * "
CHATTANOOGA. TENNESSEE 374ot 400 P l
- 2.gestnut Street Tower II 0
orn 3 November 28, 1984 L
BLRD-50-438/84-38 BLRD-50-439/84-35 U.S. Nuclear Regulatory Coinnission Region II Attn:
Mr. James P. O'Reilly, Regional Administrator 101 Marietta Street, NW, Suite 2900 Atlanta, oecrgia 30323
Dear Mr. O'Reilly:
BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 -DEFICIENT CATALYST BED IN COMSIP, INCORPORATED, HYDR 00EN ANALYZERS - BLRD-50-438/84-38, BLRD-50-439/84 FINAL REPORT The subject deficiency was initially reported to NRC-0IE Inspector P. E. Fredrickson on May 18, 1984 in accordance with 10 CFR 50.55(e) as NCR BLN NEB 8412. This was followed by our interim report dated June 19, 1984. Enclosed is our final report. We consider 10 CFR Part 21 applicable to this deficiency.
If you have any questions, please get in touch with R. H. Shell at FTS 858-2688.
Very truly yours, TENNESSEE VALLEY AUTHORITY l
Jp W.
ger Ligensin a Regulations Enclosure V
cc:
Mr. Richard C. DeYoung, Director (Enclosure)
Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C.
20555 Records Center (Enclosure)
Institute of Nuclear Power Operations 1100 Circle 75 Parkway, Suite 1500 Atlanta, Georgia 30339 8412120416 841128 p
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ENCLOSURE
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yBELLEFONTE NUCLEAR PLANT UNITS 1 AND-2 j-DEFICIENT CATALYST: BED IN COMSIP, -INCORPORATED, HYDROGEN ANALYZERS p
BLN NEB _8412-l:
= BLRD-50-438/84-38, BLRD-50-439/84-35 i.
FINAL REPORT i
Description'or Deficiency It has been. identified that the containment hydrogen analyzers catalyst beds on lBellefonte Nuclear Plant (BLN) units 1 and 2 may have a limited or diminished.
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usefull life. This is due to poisoning by fission-fragment iodine in a post-LOCA L
containment atmosphere. This deficiency was discovered from thermodynamic calculations performed by Comsip, Incorporated, and others. These calculations utilized a larger post-LOCA containment fission-fragment. iodine concentration l
(as high as.0.02 mm mercury) than was earlier assumed. Consip, Incorporated, l
estimated that the effective catalyst bed. life may be as short as ten days. TVA-was notified of this condition by NRC IE Information Notice 84-22 and by Comsip, Incorporated, 10 CFR 21 notification. This deficiency was caused by an assumed value for fission-fragment iodine concentration which may have been too low in j.
some cases.
Safety Implications The containment hydrogen analyzers are us'ed to detect the presence and concentration of post-LOCA containment atmosphere hydrogen concentration. 'This-
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f information is used by the control room operators to manually operate the
- 3 hydrogen recombiners and/or the hydrogen purge system as described in the BLN FSAR section 6.2.5.
The deficiency, if not corrected, could result in an inaccurate hydrogen gas analyzer reading following a LOCA. This could allow the t
hydrogen gas concentration in containment to exceed allowable limits (which could result in combustion or detonation of hydrogen gas) due to operator inaction." Combustion of hydrogen inside containment possibly could adversely affect the operation of essential safety-related equipment, result in doses to plant personnel greater than 10 CPR 20 limits, or result in offsite doses
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greater than 10 CFR 100 limits.
Coerective Action The existing containment hydrogen analyzers catalyst beds will be removed and l
replaced with catalyst beds of new configuration. This work will-be performed in accordance with engineering change notice (ECN) 3140. The new catalyst beds
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n are designed -to function in a post-LOCA containment atmosphere and have shown no degradation after.five months of continuous testing. The new catalyst beds are
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manufactured by Comsip, Incorporated. The use of these new catalyst beds will
- assure that the hydrogen gas analyzers can provide accurate post-LOCA containment' hydrogen concentration information for a period exceeding 100 days.
One-hundred days of postaccident operation is required by TVA's Office of Engineering calculations, f
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To prevent riscurrenca cf this dcficiency, Comsip,- ~ Incorporated, inititted W
t2 sting to gnth:r empirical data regarding ficcion-fragment iodins production in a post-LOCA containment atmosphem. Comsip, Incorporated, has subsequently produced the aforementioned new catalyst bed configuration. No fbrther action to prevent recurrence is mquired.
All corrective action for this item will be completed by October 1, 1985.
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