ML20207S856

From kanterella
Jump to navigation Jump to search
SER Re Allegation 100 on Solid Debris from Unqualified Paints Inside Containment.Debris Will Not Have Significant Adverse Effect on Operability of Containment Sump & Associated Safety Sys
ML20207S856
Person / Time
Site: Diablo Canyon  Pacific Gas & Electric icon.png
Issue date: 06/29/1984
From:
NRC
To:
Shared Package
ML17325B782 List:
References
FOIA-84-741, FOIA-84-742 NUDOCS 8703200334
Download: ML20207S856 (2)
v • d • e


Text

. .

SAFETY EVALUATION REPORT ALLEGATION 100 ,,

SOLID DEBRIS FROM UNQUALIFIED PAINTS.

INSIDE CONTAINMENT DIABLO CANYONr UNITS 1'AND 2 DOCKET NOS. 50-275/323 Characterization (Same as SSER 22)

Imolied Significance to Design, Construction, or Operation r7^

(Same as SSER 22)

Assessment of Safety Significance (Same as SSER 22)

Staff Position (Use the text of the attached memorandum dated May 18, 1984, and then add to the end of it the following:)

The staff has evaluated the consequence of potentially generating three cubic feet of debris by considering the e f fects of this debris on the net positive suction head (NPSH) available for safety systems, such as the containment spray or ECCS.

The maximum reduction in net positive suction head (NPSH) that could be caused by this amount of debrise if it were all transported to the sump intake screens, would be a small fraction 8703200334 PDR FOIA 870318 DEVINE84-741 PDR N

~~

+

of one foot of water. There is a minimum margin for NPSH of four feet of-water for the worst-case. post-accident configurations of equipment. The re f ore r it is the staff's position that three cubic feet of debris wiLL not have a signi f.i cant f adve rse effeet.on the operability of-the containment sump and the associated safety systems. Accordinglys it is acceptable for Diablo Canyon to operate with the potential to generate three cubic feet of solid debris from unqualified paints i nside containment under DBA conditions.

Action Required No further action required. .

W M

. - . _ . . - - , , . , ,- . . _ .- _. c -

. [p eer

. q, UNITED STATES .

-~ '

<J NUCLEAR REGULATORY COMMISSION 2W'Y f.S , .. % , .

7 WAsy NGTON. D. C. 20555 f - ,

-%g @ 4)f '

r* ~es -

MAY f 81984 -

MEMORANDUM FOR: Walter R. Butler, Chief Containment Systems Branch .

Division of Systems Integration Brian Sheron, Chief Reactor Systems Branch Division of Systems Integration FROM: Victor Benaroya, Chief Chemical Engineering Branch Division of Engineering

SUBJECT:

ESTIMATE OF SOLID DEBRIS FORMATION FROM UNQUALIFIED PAINTS INSIDE CONTAINMENT UNDER DBA CONDITIONS FOR DIABLO CANYON, UNITS 1 AND 2

Reference:

hemo, Victor Benaroya to Walter Butler,' February 27, 1984 We have reevaluated our estimate of solid debris formation from unqual'ified paints inside containment on the basis of the licensee's response, by letter dated May 9, 1984. The amount of debris which can be generated from unqualified paint is estimated at 500 pounds with a volume of about 3 cubic feet.

We consider that inside containment, unqualified paints which do not meet the provisions of Regulatory Guide 1.54, Quality Assurance Requirements for Protective Coatings Applied to Water-Cooled Nuclear Power Plants (June 1973), and ANSI N 101.2, Protective Coatings (Paints) for Light Water Nuclear Reactor Containment Facilities (1972), can be a source of hydrogen generation and debris formation. This is a conservative assumption becau,se all unqualified paints would not be affected.

Our initial estimate (see reference memo), concluded that the debris from unqualified paint may total 6400 pounds with a volume of 34 cubic feet.

In the licensee's letter, dated May 9,1984, additional paints were identified which have been tested in accordance with and meet the requirements of ANSI N101.2, Protective Coatings (Paints) for Light Water-Nuclear Reactor Containment Facilities (1972). Some additional unqualified paints have been removed from the estimate because they are covered with thermal insulation and will be trapped behind the insulation, thus, preventing transport to the sump.

4

)

M5.WM&W % -49:'?% : ? - .y-:-~ ' '~ -

=r

- -;q .~.

.- *i d 2 M & M % % .:'

  • "~7;'.icsYd4.%.- 4 . _

...-u;e e c MAY 1819B4 .

. Walter Butler'/ Brian Sheron'-

The quality assurance control program ipsti.tuted by the licensee for the qualified paints inside containment are comparable to the guidance provided by Regulatory Guide 1.54, Quality Assurance Requirements for Protective Coatings Applied to Water-Cooled Nuclear Power Plants. About 90% of the coatings have been in place since early 1977. The plant layup environment could be more severe than an operating environment due to condensation.

However, the qualified paints on the containment surfaces shows no evidence of chiping, flaking, holidays, bubbling or other indications of defective materials or improper application. -

The consequence of solid debris that can potentially be formed from unqualified paints are reviewed in SRP Section 6.2.2.

c,./ .

( -

~

.~=i Victor Benaroya, Chiief

" - Chemical Engineering Branch Division of Engineering

Contact:

F. Witt x28360 cc: R. Vollmer W. Johnston L. Rubenstein J. Shapaker C. McCracken C H. Schierling G. Knighton A. Serkiz J:'PiiTs'iplierT s -

F. Witt E. Sullivan

. S. Pawlicki t

i

. ' ENCLOSURE' 2 i .

. SALP prepared by the Containment Systems Branch Evalua tion Diablo Canyon, Units 1 and 2 Criteria Ca te gory _ Narrative Description i

1. Management involvenent N/A,
2. Approach to Resolution 2 The licensee has generally demonstrated understanding of the issues. Their of Technical Issues approach was viable and sound from a safety standpoint.
3. ResponsTieness 2 The licensee responded to NRC concerns in a positive and timely manner.

I .l

4. En forcemen[~RI s to ry -

N/A .

S. Reportable Events N/A i

6. Staf fing N/A l 7. ~ Training ^

N/A O

o

,

Retrieved from "https://kanterella.com/w/index.php?title=ML20207S856&oldid=3318541"