ML20207P436

Rev 4 to TVA Employee Concerns Special Program Final Rept 308.07-SQN, Clam Control Program

ML20207P436
Person / Time
Site:	Sequoyah
Issue date:	01/08/1987
From:	Murphy M, Stewart D, Swearingen F TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML20207P399	List: ML20207P398 ML20207P407 ML20207P427 ML20207P436 ML20207P447 ML20207P455 ML20207P459
References
308.07-SQN, 308.07-SQN-R04, 308.07-SQN-R4, NUDOCS 8701160133
Download: ML20207P436 (9)

Text

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l TVA EMPLOYEE CONCERNS REPORT NUNBER: 308.07-SQN

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• fi SPECIAL PROGRAN REPORT TYPE: Sequoyah Nuclear Plant - Element REVISION NUMBER: 4 TITLE: Clam Control Program REASON FOR REVISION:

To incorporate Technical Assistance Staff (TAS) and Senior Review Panel (SRP) comments. Revision 1 To incorporate Sequoyah corrective action response, Revision 2 TAS and other review coments.

To incorporate SRP and other review comments. Revision 3 To incorporate SRP coments. Revision 4 PREPARATION PREPARED BY:

F. R. Swearingen //d/f

'DATE 7

SIGNATURE r REVIEWS PEER: ,

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'DATE 5' ~I

// SIGNATURE TAS:

m OWAar/ iWn DATE V%7 SIGNATURE CONCURRENCES CEG-H: Y /f7 87 SRP: 0 i lA ) h il d b' lf7f$l DATE SIGNATURE DATE

[~SIGNATUREf//

APPROVED B Mct/ad6 ECSP MANAGER en7 DATE Nn MANAGER OF NUCLEAR POWER DATE CONCURRENCE (FINAL REPORT ONLY)

• SRP Secretary's signature denotes SRP concurrences are in files.

2536T 8701160133 DR 870109 ADOCK 05000327 PDR i

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TENNESSEE VALLEY AUTHORITY SEQUOYAH NUCLEAR PLANT ,

EMPLOYEE CONCERNS TASK GROUP

' OPERATIONS CEG Subcate5ory: Maintenance Element: Clam Control Program Report Number: 308.07 - SQN Revision 4 IN-85-948-001 IN-85-948-002 IN-85-948-003 i

Evaluator: F. R. Swearinten /// f /

F. R. Swoaring n ' Dste Reviewed by: /I / be'/ dE /['/b'?

OPS CEG'M, ember Date Approved by: e /!7[87 s W. R. Lagergren 'Date 2536T

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R2visicn 4 c e'<

I. CLAM CONTROL PROGRAM-Three concerns, IN-85-948-001,.IN-85-948-002, and IN-85-948-003 were evaluated-. 'All three concerns regard clam infestation in the following plant water systems': Essential Raw Cooling Water (ERCW), High Pressure Fire Protection (HPFP), Raw Cooling Water (RCW), and Raw Service Water (RSW). These concerns are specific to Watts Bar Nuclear Plant (WBN) and this evaluation is: performed at Sequoyah Nuclear Plant (SQN) because of the generic applicability.

The'three concerns exact wording is " mussels." Mussels do not cause

. system problems.unless salt water is the growth medium as documented by

-I. E. Bulletin 81-03, p. 3. It is assumed that the concerned individuals have mistakenly called asiatic clama, mussels, and the evaluation will cover the clam control program.

l; II. SPECIFIC EVALUATION METHODOLOGY Concern IN-85-948-001' states: " Intake pumping station cannot or does not screen out mussels. The aussels found in lines are very small and perhaps are hatching. The ERCW line is also clogged with concrete debris. An 8 inch line may have a one and a half inch opening for water flow. The fire protection system will not operate properly due to this clogging. Example: Six inch F. P. line in Unit 1 " Hot Shop" was cut 2-4 years ago, and a one foot length of pipe had enough debris to fill a j hard hat (713' Elevation behind security). C. I. had no further l

information.

Concern IN-85-948-002 ctates: " Pipes to the sprinkler heads in the switch yard are filled with mussels and debris. Examples of past

! clogging are where the four inch diameter header joins the one inch L diameter around every transformer. C. I. Had no further information."

Concern IN-85-948-003 states: "The flush hose was stopped up with mussels and identified while flushing the system two years ago.

Auxiliary Building, Unit 1, 692' Elevation. This system was F. P. and was supposed to be " dry." C. I. had no further information."

Evaluation of this element entailed identification of regulatory requirements, evidenced by the SQN FSAR and NRC IE Bulletin 81-03, verification of appropriate implementing instructions, surveillances, technical standards, etc., and analysis of program results via interviews of cognizant personnel and review of surveillance data.

Personael contacted -epe)sented the SQN site Quality Assurance organization. Planning and Scheduling, Chemical Engineering, Nechanical Maintenance, Engineering Test, and Codes and Standards.

Concern IN-85-948-001 stated that there is concrete debris in the (

essential raw cooling water (ERCW) pipe. Concrete-lined piping is f specific to WBN, and the debris issue is covered by other concerns lR4 being evaluated by the Engineering CEG under subcategory 233. l Therefore, this part of the concern is not generic to SQN and was not l evaluated, j Page 1 of 6 l

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RIvision 4 l

6 =. 4 III. FINDINGS Following the forced shutdown of a nuclear unit at another utility, NRC mandated in IE Bulletin 81-03 (reference 4) that licensees quantify lR4 clam infestation and establish a program to prevent degradation of plant equipment due to clam fouling.

In responding to the IE bulletin (see reference Sb). TVA acknowledged the presence of clams in Chickamauga Lake and made six specific commitments to minimize infestation: ,

1. Continuous chlorination of ERCW when Tennessee River temperature exceeds 60*F.

2. Chlorination of Flec Protection System for approximately three weeks each fall and spring.

3. Annual inspection of ERCW piping for corrosion products and class.

4. Testing of Fire Protection systems every three years to verify ability to achieve rated pressure and flow.

5. Semiannual flushing of Fire Protection hose stations and yard hydrants, coincident with chlorination of the system.

6. Annual test of centrifugal charging pump and safety injection pump bearing cooler temperature drop.

In a September 7, 1982 response to NRC regarding a SQN unit 2 operating license condition (see reference Sc). TVA amended the clam control commitments related to the ERCW system. The fire protection system commitments remain as before. Following are the revised ERCW actions:

1. Same as (1) above.

2. Item (3) above, annual ERCW pipe inspection, was deleted. IR4

3. An overall heat exchanger inspection program will be instituted.

4. Evaluation of chlorination equipment failures lasting more than 14 days will be made to determine need for additional flushing or other treatment.

5. Surveillance Instruction SI-566, which was run in 1982 to verify overall ERCW performance, will be run again in 1983.

Additionally TVA committed to NRC on March 21, 1983 (reference Sa) to maintain chlorine concentration in ERCW, RCW, RSW, and HPFP at 0.6 to 0.8 ppm during treatment periods.

Page 2 of 6

R'svisicn 4 s , ,

Irplementation of the commitments begins with Sequoyah Standard Practice SQN 32, Asiatic Clam Control, and Technical Standard (TS) 08.01.01.14.03. These documents are not. working level procedures ,

and are thus not approved by the Plant Operations Review Committee (PORC), but outline SQN's actions in this area. The actual procedures for clam control are contained in three Surveillance Instructions (SI) and four other sis which cover the detection and trending commitment.

A minor discrepancy exists between the SI and the commitment in that the SI calls for chlorination from May through October, irrespective of river water temperature. This discrepancy-is in the conservative direction and is only noted here.

Commitment I for continuous chlorination of the ERCW system is implemented by SI-712. This instruction describes the chlorination process and documents its performance and the resultant -

concentrations. Review of data packages for SI-712 from its initiation in July 1985 to the present indicates that chlorination is being done per the instruction.

Commitment 2 chlorination of RCW, RSW and HPFP during the clam spawning periods is also part of SI-712. Again, this is being done as prescribed.

The third commitment, evaluation of chlorination equipment failures to sscertain need for chlorine shock treatments is discussed in SI-712, but no data sheets or other documentation is required.

The commitment for bearing temperature testing is implemented by SI-40 for the centrifugal changing pumps, and SI-129 for the safety injection pumps. Although these instruction do not specifically reference clam control, they do meet the commitment.

SI-679 satisfies the commitment for a heat exchanger inspection program. Review of an informal sample of the data sheets for this instruction revealed no evidence of clam infestation. This form provides a space to document infestation should it occur. It should be noted that in some cases these data sheets are missing data entries and signatures.

sis 122,185 and 148 are hydraulic performance and flushing instruction for HPFP yard and building systems.

They satisfy the two original fire protection clam control commitments.

When SI-566 was first run in March 1982, Sequoyah personnel discovered

, that clams had grown inside the ERCW inlet nozzle of Containment Spray Heat Exchanger (CSHX) 1A. No other CSHK was affected, and SQN ONP determined the infestation was an isolated case.

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Rsvisicn 4 When S1-566 was run again in 1983, no clam infestation was observed.

This satisfied the commitment made to NRC in the September 7, 1982 letter (reference Sc).

Informal interviews with individuals in mechanical maintenance, chemical engineering, safety and fire protection supported the above finding of only minor problems with class in the fire protection systems. The interview also revealed that numerous pipes have been cut open during modifications with virtually no clams found, and that strainers and baskets removed per MI-6.24 and applicable sis (reference 7) have not revealed major clam infestation.

Conclusions Reviews of all pertinent documents and interviews with personnel indicate that there are clams in the vicinity of SQN and that clam growths have occurred in some of the water systems. The evaluation, however, found no indication of any massive or recurring problem with clams in plant water systems. Concerns IN-85-948-001, IN-85-948-002, and IN-85-948-003 generically evaluated at SQN are therefore found not valid.

The plant sis are adequate to prevent clam infestation, but no procedure was found which specifically met the NRC commitment that chlorine equipment failures will be evaluated.

IV. ROOT CAUSE Since these concerns were evcluated generically for SQN and no clam infestation problems exist at SQN, no root cause was determined.

V. GENERIC APPLICABILITY In the documents reviewed, it was found that clam infestation is a potential problem at all TVA nuclear plants. However, the clan control program at SQN is specific to SQN and the findings cannot be applied to other plants.

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- R2Vislen 4 VI. REFERENCES

1. Employee Concerns IN-85-948-001, IN-85-948-002, and IN-85-948-003

2. Element Report: SQN Generic Concern Task Force; April 25, 1986, R1;

" Mussels and Construction Debris Clogging ERCW and Fire Protection-Flow Paths"

3. Element Report: WBN Employee Concerns Task Group - No. 308.07;

" Clam Control Program"; Draft dated Apell 21, 1986

4. IE Bulletin 81-03 (enclosed with letter from James P. O'Reilly to H. G. Parris dated Apell 10, 1981)

5. a. Letter to Mr. O'Reilly USNRC, dated March 21, 1983, from D. S. Kammer, TVA, " Flow Blockage of Cooling Water to Safety Components by Corbicula" (A27 830321 019)

b. Letter to Mr. O'Reilly from L. M. Mills dated May 26, 1981, "I. E. Bulletin 81 Sequoyah Nuclear Plant" (A27 810526 028)

c. Letter to E. Adenson, USNRC, from Mr. Mills dated September 7, 1982, " Docket Nos. 50-327, and 50-328" (A27 820907 034)

6. SQN FSAR - Section 9.2.2.6

7. SQN' sis: 171'RO, 692 RO, 712 R2, 122 R4, 185 RS, 148 R4, 40 R35, 129 R27, 704 R2, 679 R2, 181,3 RO, 181.4 RO, and 181.5 R0

8. SQN SI data sheets:

SI-171 SI-712 SI -679 171.2 A - 05/09/85 Data Sheet 1 03/84 171.2 F - 05/09/85 08/05/85 to 09/29/85 10/84 171.2 J - 05/09/85 10/21/85 to 11/18/85 02/85 171.3 04/17/86 to 05/26/86 09/27/85 171.1 - 10/20/83 10/01/85 10/10/85 01/86

9. SQN MI-6.24 R1

10. SQM 32 R1

11. T. S. 08.01.01.14.03 R0 Page 5 of 6

Rzvisicn 4 VII. IMMEDIATE OR LONG-TERM CORRECTIVE ACTION Chlorination equipment failures are addressed in SQM 32 and SI-712.

According to TVA's aquatic biologist, " flushing" refers to the use of IR4 non-chlorinated water, and " shock chlorination" is synonymous with

" continuous chlorination."

SQN's procedures call for continuous chlorination (shock chlorination).

Whenever chlorination is interrupted, for any reason including equipment failures, the required action is to reestablish continuous chlorination.

A determination will be made whether or not to elaborate on the wording

(" chlorine equipment failures will be evaluated for adding flushing or shock chlorination"). at the time the next revision is made to SQM 32 and SI-712, to make the meaning clearer to the average reader. A revision to do so is not required at the present time.

Data sheets to document equipment failures are not required; no commitments were made to the NRC to do so.

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-n REFERENCE - ECPSI20J-ECPS121C TENNESSEE VALLEY AUTHORITY PA7E- -

- REQUEST .

OFFICE OF NUCLEAR POWER RUN TIME'- I; i FREQUENCY '

anP - ISSS - RHM EMPLOYEE CONCERN PROGRAM SYSTEM (ECPS) RUN DATE - It' LIST OF EMPLOYEE CONCERN INFORMATION '

CATEGORY: OP PLAUT OPER. SUPPORT SUBCATEGORYs'30807 CLAN CONTROL '

- S GENERIC KEYHORD A H APPL QTC/NSRS P. KEYWORD B

~ CCNCERN SUB R PLT BBSH INVESTIGATION S CONCERN KEYNORD C NUMBER C/ T CAT D LOC F4QB REPORT R DESCRIPTION KEYWORD D IN 948-001 OP 30807 N HBN YYYY INTAKE PUMPING STATION CANNOT OR DOE NONCONFORMANCE T50251 K-FORM S NOT SCREEN DUT MUSSELS. THE MUSSE CORRECTIVE ACT LS FOUND IN LINES ARE VERY SMALL AND PIPING PERHAPS ARE HATCHING. THE ECRH LIN PIPE E IS ALSO CLOGGED WITH CONCRETE DEBR IS. AN 8" LINE MAY HAVE A 1 1/2" DP ,

ENING FOR HATER FLOH. THE FIRE PROT ECTION SYSTEM HILL NOT DPERATE PROPE RLY DUE TO THIS CLOGGING. EXAMPLE:

6" F.P. LINE IN UNIT 1 " HOT SHOP" HA S CUT 2-4 YEARS AGO, AND A l' LENGTH OF PIPE HAD ENOUGH DEBRIS TO FILL A

• HARD HAT (713' ELEV. BEHIND SECURIT

, Y). CI HAD NO FURTHER INFORMATI IN 948-002 OP 30807 N HBN YYYY PIPES TO THE SPRINKLER HEADS IN THE HONCONFORMANCE T50251 K-FORM SHITCH YARD ARE FILLED WITH MUSSELS CORRECTIVE ACT:

AND DEBRIS. EXAMPLES OF PAST CLGGGI PIPING NG ARE WHERE THE 4" DIAMETER HEADER PIPE JOINS THE DIAMETER ARCUND EVERY T RANSFORMER.1". CI HAD NO FURTHER INFOR j MATION. CONSTRUCTION DEPARTMENT CON CERN.

IN 948-003 OP 30807 N kBN YYYY THE FLUSH HOSE HAS STOPPED UP HITH M NDHCONFORMANCE T50251 K-FORM USSELS AND IDENTIFIED HHILE FLUSHING FLUSHING THE SYSTEM TH0 YEARS AGO. AUX. BLD SYSTEMS G., UNIT 01, 692' ELEV. THIS SYSTEM PIPE WAS F.P. AND HAS SUPPOSED TO BE "DR <

Y". CI HAD NO FURTHER INFORMATION.

CONSTRUCTION DEPARTMENT CONCERN.

3 CONCERNS FOR CATEGORY OP SUBCATEGORY 30807 l

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