ML20072H251

Responds to IE Bulletin 81-03, Flow Blockage of Cooling Water to Safety Components by Corbicula Sp (Asiatic Clam) & Mytilus Sp (Mussel). No Significant Fouling or Flow Blockage by Corbicula Shells Discovered

ML20072H251
Person / Time
Site:	Farley
Issue date:	03/22/1983
From:	Clayton F ALABAMA POWER CO.
To:	Jordan E NRC OFFICE OF INSPECTION & ENFORCEMENT (IE)
References
REF-SSINS-6820 NUDOCS 8303290354
Download: ML20072H251 (2)

Text

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• Alabama Power Company 600 North 18th Street Port Office Box 2641 Crmingham, Alabama 35291 Telephone 205 783-6081 F. L Cloyton, Jr.

% 2 ' L 7 % ','"' AlabamaPbwer thesourhem emncsystem March 22, 1983 Docket Nos. 50-348 50-364 Mr. E. L. Jordan, Director Division of Engineering and Quality Assurance Office of Inspection and Enforcement U. S. Nuclear Regulatory Cor.wission Washington, D. C. 20555 Joseph M. Farley Nuclear Plant - Units 1 and 2 I. E. Bulletin 81-03

Dear Mr. Jordan:

In response to your January 21, 1983 letter requesting additional information related to I. E. Bulletin 81-03, " Flow Blockage of Cooling Water to Safety Components by Corbicula Sp.-( Asiatic Clam) and Mytilus Sp.

(Mussel)," Alabama Power provides the following:

NRC Request: The inspections and flow tests performed in response to the bulletin were minimal (three heat exchangers inspected on Unit 1 and a flow test performed on a single heat exchanger in Unit 2). Your response states "we are planning to inspect all remaining Unit 1 safety-related heat exchangers

. . ." Please provide the results of these inspections and'

.iustify their applicability to Unit 2.

APCo Response: Alabama Power Company's letter of October 29, 1982 (Attachment 1), provided the results of followup inspections at Unit 1 and Unit 2. A total of 22 heat exchangers were inspected (19 in Unit 1 and 3 in Unit 2) and revealed no evidence of Corbicula or Corbicula shells.

l Complete details of the inspections are contained in the attached October 29, 1982 letter.

j The service water systems for Units 1 and 2 have a comon /glf l source of water such that the Unit 1 inspections are M l representative of the conditions at Unit 2. Additional ly, l

as documented in the October 29, 1982 letter, Unit 2 l safety-related heat exchangers have been inspected l' verifying the fact that no Corbicula problems are evident at either Unit 1 or Unit 2.

8303290354 830322 PDR ADOCK 05000348 O PDR

Mr. E. L. Jordan March 22,1983

-U. S. Nuclear Regulatory Commission .Page 2 NRC Request: Discovery of some shells in several heat exchangers prior to issuance of Bulletin 81-03 is evidence of fouling although flow restriction did not occur. Please provide descriptions of the extent of fouling and how and when it was discovered.

APCo Response: No significant fouling or flow blockage of heat exchangers due to Corbicula shells has been found at the Farley Nuclear Plant. A few isolated individual shells were fourxi during component inspections at the first refueling outzge for Unit 1 (this outage began in March 1979 and lasted until November 1979). Some additional indication of shells in the 1C CCW heat exchanger was found during the current Unit I refueling outage which began in January 1983.

Again, no significant fouling or flow blockage of heat exchangers due to Corbicula shells has been found at the Farley Nuclear Plant.

NRC Request: Provide more complete description of chlorination progrzm, including dose concentrations, and residual concentra-tions. Insufficient information was provided to assess effectiveness of program.

APCo Response: The chlorination program for the service water system .is described in section 9.2.1.6 of the FSAR. The dose concentration for the chlorinator is set at 0.5 ppm free chlori ne. Samples at the service water pump discharge have indicated residual values of 0.4 to 0.6 ppm. Presently this system is shutdown for maintenance which is scheduled to be completed in April 1983.

If you have any additional questions, p' cat- ad71se.

You rs ve o 1 . l.,

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F. L. Clayton, JI[.

FLCJ r/GGY:lsh-D16 Attachments

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Mr. R.- A. Thomas Mr. G. F. Trowbridge Mr. S. A. Varga Mr. J. P. O'Reilly Mr. E. A. Reeves Mr. W. H. Bradford

Malting Address -

, . . Aiabama Power C mpany

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• 600 North 18th Street 2:C*!"Li"'a me, 1.i.phoo. m m.ao8i ATrAc4 M ENT 1 }

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N2' ';0%'*"' AlabamaPbwer the southern electre system

' October 29, 1982 I Docket No. 50-348 Mr. J. P. O'Reilly U.S. Nuclear Regulatory Commission Region II, Suite 3100 101 Marietta Street N.W.

Atlanta, Georgia 30303 Joseph M. Farley Nuclear Plant - Unit 1 I.E. Bulletin 81-03 Item 4.8

Dear Mr. O'Reilly:

In letter dated May 26, 1981, Alabama Power Company committed to provide additional information regarding I.E. Bulletin 81-03 Item 4.b. The following updated information is provided in regard to this subject.

On August 14, 1979, photographs of the 1A component cooling water (CCW) heat exchanger indicated no tube blockage by Corbicula (clams). Information regarding this safety related heat exchanger is given in the attachment.

~ Subsequent to the May 26, 1981 response, all the charging pump room, bearing oil, and gear oil coolers on both units have been inspected. These inspections revealed no blockage problems due to

! Corbicula or Corbicula shells (see attachment).

! An extensive program of inspecting and cleaning various non-safety related heat exchangers was conducted on Unit I from September 1981 to March 1982. No evidence of Corbicula A or summary of Corbicula shells was found during these inspections.

these non-safety related heat exchangers is given in the

[ attachment.

By the above information and the letter of May 26, 1981, it is the judgement of Alabama Power Company that the provisions of I.E.

Bulletin 81-03 item 4.b have been met. No future inspections of Unit 1 safety related heat exchangers, except during routine maintenance operations, are therefore planned.

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I l Mr. J. P. O'Ro111y U.S. Nuclear Regulatory Commission October 29, 1982 Page 2

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If you have any questions, please advise.

Yours very truly,

-- n 3 k a.o I% (#

F. L Clayton, J FLCJ r/RGW:jc-D29 Attachment cc: Mr. P.. f.. Themas Mr. G. F. Trowbridge

• Mr. S. A. Varga Mr. E. A. Reeves Mr. W. H. Bradford G

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ATTACHMENT Safety-Related Heat Exchangers Inspected

1. Component Cooling Water Heat Exchanger, Unit 1 Location: Aux. Building EL100

• Pipe Inlet I.D.: 20 inches Clams or clam shells found: None [

r- Number of blocked tubes observed: None I-

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2. Charging Pump Room, Bearing 011, and Gear Oil Coolers-Units 1&2 Location: Aux. Building EL 116 (6 coolers)

Pipe Inlet I.D.: 25' inches Clams or clam sheels found: None Number of blocked tubes observed: None Non-Safety Related Heat Exchangers Inspected

1. Main Turbine Generator Hydrogen Heat Exchanger-Unit 1 Location: Turbine Building EL 200 Pipe Inlet I.D.: 8 inches Clam or clam shells found: None Number of blocked tubes observed: None

2. Main Condenser-Unit 1 Location: Turbine Buf1 ding EL 145 (4 sections)

Pipe Inlet I.D.: 96 inches Clams or clam shells found: None Number of blocked tubes observed: None

4. Hydrogen Seal Oil Coolers-Unit 1 Location: Turbine Building EL 137 (2 coolers)

Pipe Inlet I.D.: 4 inches Clam or clam shells found: None

- Number of blocked tubes observed: None

5. Turbine Lube Oil Coolers-Unit 1 Location: Turbine 3uilding EL 155 (2 coolers)

Pipe Inlet I.D.: 10 inches Clams or clam shells found: None Number of blocked tubes observed: None

6. Turbine Building HVAC Chillers-Unit 1 Location: Turbine Building EL 275 (2 chillers)

Pipe Inlet I.D.: 6 inches Clams or clam shells found: None Number of blocked tubes observed: None

7. Main Turbine Generator Exciter Coolers-Unit 1 Location: Turbine Building EL 195 (2 coolers) t Pipe Inlet I.D.: 25 inches Clams or clam shells found: None Number of blocked tubes observed: None 9

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8. Steam Generator Tecd Pump Oil Coolers Location: Turbine Building EL 157 (2 coolers)

Pipe Inlet I.D.: 3 inches Clams or clam shells found: None Number of blocked tubes observed: None .

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