ML20071B928
| ML20071B928 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 02/17/1983 |
| From: | Mills L TENNESSEE VALLEY AUTHORITY |
| To: | Oreilly S NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| REF-SSINS-6820 IEB-81-03, IEB-81-3, NUDOCS 8303010303 | |
| Download: ML20071B928 (3) | |
Text
A 6,
~
TENNESSEE VALLEY AUTHORRT2(RECn },
- CHATTANOOGA. TENNESSEE 3'74ot '
400 Chestnut Street Tower II
}]'{Tyg23. AID.<ll February 17, 1783
?U.S. Nuclear' Regulatory Commission
' Region II, ATTN: James P. O'Reilly, Regional Administrator 101 Marietta Street, Suite 3100
-Atlanta, Georgia 30303
Dear Mr. O'Reilly:
OIE BULLETIN 81 FLOW BLOCKAGE OF COOLING WATER TO SAFETY COMPONENTS BY CORBICULA SP. (ASIATIC CLAM) AND MYTILUS SP. (MUSSEL)
As requested by E. L. Jordan's letter to me dated Deceuber 14, 1982, encicsed is TVA's action response to the supplemental questions transmitted by that letter. Since Hartsville Plant B and Phipps Bend have been cancelled and Hartsvillo Plant A and Yellow Creek have been deferred, the enclosed response centers on activities at Bellefonte Nuclear Plant (Docket Nos.. 50-438, -439). If you have any questions, please call Jim Domer at FTS 858-2725.
To the best of my knowledge, I declare the statements contained _
herein are complete and true.
Very truly yours, TENNESSEE VALLEY AUTHORITY
\\
L. M. Mills, Ma ager Nuclear Licensing Enclosure cc:
Mr. R. C. DeYoung, Director (Enclosure)
Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C.
20555 8303010303 830217
~
PDR ADOCK 05000438 O
PDR An Equal Opportunity Employer yg
F
' =
ENCLOSURE Kesponse to NRC request for Supplemental Information on IE Bulletin 81 Flow Blockage of Cooling Water to Safety System Components.by Corbicula Sp. - Bellefonte Nuclear Plant.
Question 2.
Provide safety system history of most recent inspections and performance tests, including all components filled as well as those potentially affected.. Inasmuch as no attempt was made.to inspect these systems as a result of this bulletin, the basis for TVA's assessment of "no infestation" should be documented.
Response
Inspections During the past six months, inspecti5ns of the essential"r'aw codling'
~ ~ ~ ~ ~ ~
~
water (ERCW) eystem have produced no evidence of Asiatic clam infestation. Selcw is a represectative sample of areas which have _.
been inspected.
1.
Tube side of component cooling water heat exchanger.
2.
Cocling water passages of the water cooler for the anit 1 air compressors.
3 ERCW side of the control rod drive cooling water heat exchangers.
4.
Cooling water jacket and passages for unit 1 air compressor.
5.
The ERCW supply headers from the intake pumping station to the Auxiliary Building.
Similarly, during the past six months, the raw service water /high pressure fire protection (HPFP) system has been inspected and no evidence of clam infestation found.
Portions inspected were (among others):
1.
Four fire hydrants located in the yard that had been in service for approximately three years.
2.
Eight-inch fire protection header in the Auxiliary Building.
3 Numerous valves (valves removed and piping on each side inspected).
To date, no performance tests have been conducted on the raw water systems at Bellefonte.
J..
.n-
~.,--..-,,eo-,.n.
,gr,,,--.. - -., -
,,-._-._-----c,,_,,n-n, m,
- - ~,,
r----
.n r,,,--.
I
.a.
- Question 3
e.
Provide a description of planned biocide treatment for Corbicula control. Include frequency of application and dosage levels specific to sodium hypochlorite. systems.
Response
The ERCW system will be chlorinated continuously during the clam spawning period. The water will be treated with total residual chlorine of'0.6 to 0.8 ppm concentration. Based on our studies to date, this level of chlorine is necessary to obtain assurance that our program is adequate; however, the chlorine concentration will be changed if our further studies indicate a necessity to do so. Our main goal is to optimize chlorine level while' maintaining adequate clam control. Equipment failures resulting in loss of chlorination in excess of 14 days will be evaluated to determine if additions 1 ~~
- - - - - ~ ~ - -~
flushing or shock chlorir.ation is required to teturn the system to a normal condition.
To effect clam control in the HPF? sy.' tee; which is orpplied by the raw service water syatem, e asall contir.uous flow of chlorinated water will oe established during cle.m spawning season throuSh all major fira protecticn headers except those fire protection systems or parte thereof ordinarily not exposed to raw water, (i.e.. filled with chemically-treated water or stored dry).- Equipment failures resulting in loss of chlorination in excess of 14 days will be evaluated to determine if additional flushing or shock chlorination is required to return the system to a normal condition.
c 4
R b
.