ML20236E618

Rev 0 to Piping & Valve Design:Carbon Steel Vs Stainless Steel Drainage Piping, TVA Employee Concerns Special Program Element Rept

ML20236E618
Person / Time
Site:	Sequoyah
Issue date:	01/05/1987
From:	Griffith J TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML20236E191	List: ML20236E186 ML20236E237 ML20236E273 ML20236E282 ML20236E287 ML20236E291 ML20236E294 ML20236E298 ML20236E304 ML20236E309 ML20236E325 ML20236E329 ML20236E350 ML20236E496 ML20236E516 ML20236E613 ML20236E618 ML20236E649 ML20236E657 ML20236E672 ML20236E675 ML20236E693
References
232.2(B), 232.2(B)-R, 232.2(B)-R00, NUDOCS 8710290286
Download: ML20236E618 (8)

Text

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TVA EMPLOYEE CONCERNS REPORT NUMBER:

232.2(B)

I SPECIAL PROGRAM l

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REPORT TYPE:

SEQUOYAH ELEMENT REVISION NUMBER: 0 S

TITLE:

PIPING AND VALVE DESIGN Carbon Steel vs. Stainless Steel Drainage Piping PAGE 1 0F 8 REASON FOR REVISION:

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PREPARATION PREPARED BY:

/2 -3/-86 i

g yGNATURE DATE REVIEWS RE C0091ITT E:

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DATE f v 51GNATURE g

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TAS:

SIGNATURE DATE CONCURRENCES 8710290286 071023 I, - as/

/-[f7 PDR ADOCK 05000327 q-P PDR CEG-H:

dYnd IT'77 SRP:

SIGNATURE DATE SIGNATURE DATE APPROVED BY:

ECSP MANAGER DATE MANAGER OF NUCLEAR POWER DATE CONCURRENCE (FINAL REPORT ONLY) x

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REPORT' NUMBER:

232. 2( B ). -

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'TVAEMPLOYEE'CONCERNSL SPECIAL PROGRAM

.j REVISION NtMBER:

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PAGEl2 0F 8 j

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1.., CHARACTERIZATION OF ISSUES:

LConcerns:

Issues:

j a.

The reactor building floor drain-IN-85-021 -006' piping design drawings may have "The floor drain piping is-carbon steel and:should be required the use of carbon steel stainless stcel in reactor instead of stainless. steel piping a

~ building 1 ant 2."

material.

XX-85-127-002.

b.

Carbon steel pipe may have been "Sequoyah - floor drain piping installed in the reactor building is carbon steel and it should be floor drain system instead of

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. stainless steel.. Reactor. Bldg."

stainless. steel as required by the design drawings.

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2.

HAVE ISSUES BEEN IDENTIFIED IN ANOTilER SYSTEMATIC ANALYSIS? YES X NO Identified by TVA Nuclear Safety Review Staff (NSRS)

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Date March 6,1986 -

Documentation Identifiers:

NSRS Investigation Report No. I-85-921-SQN, Reactor Building Raceway Drains, (03/06/86) 3.

DOCUMENT NOS., TAG NOS., LOCATIONS OR OTHER SPECIFIC DESCRIPTIVE IDENTIFICATIONS STATED IN ELEMENT:

Sequoyah Reactor Buildings 1 and 2 floor drain piping.

4.

INTERVIEW FILES REVIEWED:

Files IN-85-021 and XX-85-127 reviewed 06/18/86, contained only K-foms.

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L 06940 - December 31, 1986 sa-a- - - - -,. _ _,

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TVk EMPLOYEE CONCERNS REPORT NUMBER':

232.2(B)

SPECIAL PROGRAM REVISION NtMBER:. 0

'PAGE 3 0F"8 d

5.

'DOCIEENTS REVIEWED RELATED TO THE' ELEMENT:

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See Appendix A.

6.-

WHAT. REGULATIONS, LICENSING COWilTMENTS,, DESIGN REQUIREMENTS OR OTHER APPLY OR CONTROL IN THIS AREA?

See Appendix A..

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7.

LIST REQUESTS-FOR INFORMATION, MEETINGS, TELEPHONE CALLS, AND OTHER DISCUSSIONS RELATED TO ELEMENT.

See Appendix A.

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EVALUATION PROCESS:-

a.

Reviewed SQN FSAR Section 9.3.3 for. design. bases. and-

~ description of reactor building floor drain system and

- Section 3.2.2.6 for system safety classification.

b.

Rev'ewed SQN reactor building drainage flow diagram, piping installation drawings, and bills of material listed in App.

A, 5 d.

Reviewed.SQN design criteria manual and TVA Mechanical Design c.

Guide DG-M8.1.6, Nonradioactive Building Drainage Requirements," for basic design criteria applicable to the i

reactor building drainage system.

d.

Reviewed TVA Nuclear Safety Review. Staff (NSRS) Investigation Report No. I-85-921 -SQN.

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e..

Reviewed TVA purchase requisitions for supply of reactor building drainage system materials specified on the piping drawings and relevant bills of material.

f.

Sumarized information developed from document reviews and i

evaluated the significance and validity of issues identified in the concerns.

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E 0694D - December 31, 1986 j

e TVA EMPLOYEE CONCERNS REPORT NUMBER:

232.2(B).

h SPECIAL~ PROGRAM REVISION NtMBER:

0'

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PAGE 4 0F.8-

9..

DISCUSSION, FINDINGS, AND CONCLUSIONS:

Chronology:

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12/09/86:

Concerns documented on Employee Concern Assignment Request forms by Employee Response Team (ERT) 12/12/85:

TVA Nuclear Safety Review Staff (NSRS) initiated investigation of perceived problem identified in concerns 03/06/86:-

NSRS Investigation Report No. I-85-921-SQN issued with a Priority 2 (P2) recommendation 05/13/86:

SQN plant staff responded to the NSRS recommendation Discussion:

1 The employee. concerns received by the Quality Technology Company (QTC)/ Employee Response Team (ERT) pertain to the suitability of carbon steel piping material used in the SQN Reactor Building floor -

drain-system.

The concerned individuals stated that stainless steel piping should have been used.

It was unclear from their statement whether the perceived prebha was considered one of construction or design.

Therefore, the NSRS. investigation and this evaluation of the concern have addressed'both aspects.

The reactor building embedded floor drain piping is TVA nonnuclear safety class L as noted on SQN basic design drawing.47W851-1 R17,

" Mechanical Flow Diagram, Floor and' Equipment' Drains, Reactor Building Units 1 and 2."

Sequoyah Nuclear Plant FSAR Table 3.2.2-3 identifies no specific code jurisdiction (" unclassified")

applicable to TVA class L piping system for field fabrication, examination, and testing.

The piping design complies with ANSI B31.1-1967, " Power Piping Code" and, since the reactor building is a Seismic Category I structure, the nonnuclear safety piping located inside is seismically supported as necessary to prevent unacceptable interactions with safety-related components.

The SQN FSAR Section 9.3.3 design bases identify the reactor building floor drain system as a portion of an independent chemical waste collection and disposal system which prevents uncontrolled releases of hazardous materials to the environment.

The floor drain piping material selection is based on the fluid to be handled being water and air as identified in FSAR Table 9.3.3.

The TVA engineering practice, as documented in Division of Engineering Design, Mechanical Design Guide, DG-M8.1.6, " Nonradioactive j

Building Drainage Requirements," is to use carbon steel pipe and fittings with cast iron drainage fittings unless there are special I

l 06940 - December 31, 1986 I

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I TVA EMPLOYEE CONCERNS REPORT NUMBER:

232.2(B)

SPECIAL PROGRAM REVISION NUMBER:

0 l

PAGE 5 0F 8 l

1 considerations.

In the reactor building application the embedded

' floor drain piping has been specified on SQN drawings 47W476-1 and 2 as carbon steel in the annulus area (outside of containment)'and j

stainless steel inside containment below elevation 738.0 ft.

Because of its superior corrosion resistance and ease of decontamination, stainless steel is used for embedded floor drainage piping inside containment in locations where there is a possibility of handling radioactive fluids.

(SQN Element Report -

229.2(B) addresses a related issue pertaining to the potential for spread of radioactive contamination through the reactor building 2

floor drain system.)

The TVA Nuclear Safety Review Staff (NSRS) conducted an investigation to evaluate the validity of the concern by identifying the reactor building floor drain piping material requirements and by inspection of the installation where accessible

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for compliance. The NSRS investigation reviewed design drawings and bills of material to identify the reactor building drain j

arrangements and material requirements.. Available relevant l

i installation and inspection records were also reviewed and SQN site personnel familiar with the installation. procedures were interviewed.

The NSRS investigators performed visual inspection and magnetic testing of the accessible embedded floor drain pipe ends in the containment raceway of both Units 1 and 2.

The NSRS investigation verified the use of stainless steel embedded floor drainage piping in accessible containment raceway areas as called for on the design drawings and found no evidence that carbon steel pipe was used in these areas. The NSRS Investigation Report No.

I-85-921-SQN concluded the concern was not substantiated.

In the course of their verification inspections the NSRS investigators discovered that nonstainless steel material had been used for floor drain grates where stainless steel was specified on the design drawings.

The NSRS investigation report recommends correcting the condition of using nonstainless grating material where stainless grates are specified on the design drawings.

The

)

SQN plant staff response ( App. A, 5.g) to the NSRS report recommendation committed to replacing the noncomplying grates with l

stainless steel grates.

Findings:

a.

Both carbon steel and stainless steel materials have appropriate applications in the reactor building floor i

drainage piping systems, and both have been used in the design and installation.

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TVA EMPLOYEE CONCERNS

-REPORT NUMBER:- 232.2(B).

SPECIAL PROGRAM

.a

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REVISION NUMBER:: 0 7

PAGE 6 0F 8-3

'b..

The. superior serviceability of stainless steel piping'is;

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justified in those reactor building drainage systems where-

there is. a potential for handling radioactive.or borated water, and stainless steel material has been specified in 'the

-design for.use in those systems.

c..

Stainless steel piping has been installed in the reactor -

building drainage systems where required by tho' design.

However, some installed floor' drain gratings have been u

identified that are not in. compliance with the installation drawings.

This discrepancy is being corrected by TVA.

d.

The-reactor building embedded drainage piping material is not a nuclear ' safety. issue.

Concl usion:--

'Neither concern is substantiated, and both issues identified are invalid.

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CORRECTIVE ACTION:-

'No corrective action is required.

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0694D - December 31, 1986 i

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1 TVA EMPLOYEE CONCERNS-REPORT NUMBER:

232.2(B) l SPECIAL PROGRAM j

REVISION NUMBER: 0

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PAGE 7 0F 8 APPENDIX A 5.

DOCUMENTS REVIEWED RELATED TO THE ELEMENT:

TVA, Sequoyah Nuclear Plant, Final Safety Analysis Report a.

(FSAR), ( Anendment 3) b.

TVA, Sequoyah Nuclear Plant, Design Criteria Manual c.

TVA, Mechanical Design Guide DG-M8.1.6, " Nonradioactive Building Drainage Requirements," (08/17/82) d.

TVA, Sequoyah Nuclear Plant Drawings 47W851-1 R17 Mechanical Flow Diagram, Reactor Building Floor and Equipment Drains 47W476-1 R9 -

Reactor Building Annulus Floor Drains and Embedded Piping 47W476-2 R10 Reactor Building Containment Drains and Embedded Piping 47BM476 R1 Piping Bill of Material, Reactor Building Annulus Floor Drains and Emb. Piping 47BM476-1 R2 Piping Bill of Material, Reactor Building Containment Drains and Emb. Piping e.

TVA NSRS Investigation Report No. 1-85-921-SQN, " Reactor Building Raceway Drains," (03/06/86) f.

TVA memo from K. W. Whitt to H. L. Abercrombie, " Nuclear Safety Review Staff Investigation Report Transmittal,"

(03/07/86) l TVA memo from H. L. Abercrombie to R. F. Denise, "NSRS g.

Investigation Report No. I-85-921-SQN," (05/13/86) h.

TVA Purchase Requisition No. 92621 (03/16/70) and No. 92638 (08/05/70) for floor drain materials 0694D - December 31, 1986

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• 4.40-TVA EMPLOYEE CONCERNS REPORT NUMBER:

232.2(B)-

4".

SPECIAL PROGRAM I'

REVISION NUMBER:

0-PAGE 8 0F 8 3

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. APPENDIX A (cont'd)

' 6. '

WHAT REGULATIONS, LICENSING COMMITMENTS, DESIGN REQUIREMENTS OR OTHER APPLY OR CONTROL IN THIS AREA?

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10CFR Part 50, Appendix.B, Criterion VIII, " Identification

-and Control of Materials, Parts,' and Components" ib.

SQN FSAR Sections 3.1. 2.1, 3. 2. 2. 6 and, 9. 3. 3

=

7.

LIST REQUESTS FOR-INFORMATION, MEETINGS,- TELEPHONE CALLS, AND OTHER DISCUSSIONS RELATED TO ELEMENT.

a.

RFI SON-508 (08/25/86) b.

RFI SON-736 (11/24/86) c.

TVA SQN Transmittal:#100 (08/27/86)

.d.

TVA SON Transmittal #153 (11/17/86) e.

.TVA SON Transmittal- #159 (11/25/86)

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I 0694D - December 31,.1986 AM I