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Discusses 931123 Enforcement Conference Held in Region IV Ofc Re Apparent Violation Identified in Insp Repts 50-313/93-31 & 50-368/93-31 on 931116 & Forwards Meeting Summary & Related Attachments
	ML20058E442
Person / Time
Site:	Arkansas Nuclear
Issue date:	11/30/1993
From:	Beach A; NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To:	Yelverton J; ENTERGY OPERATIONS, INC.
References
	NUDOCS 9312070015
	Download: ML20058E442 (84)
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NOV 3 01993

Dockets:

50-313

50-368

Licenses: OPR-51

NPF-6

Entergy Operations, Inc.

ATTN:

J. W. Yelverton, Vice President

Operations, Arkansas Nuclear One

Route 3, Box 137G

Russellville, Arkansas 72801

This refers to the enforcement conference conducted at NRC's request in the

Region IV office on November 23, 1993. This enforcement conference related to

an apparent violation identified in NRC Inspection Report 50-313/93-31;

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50-368/93-31, dated November 16, 1993, and was attended by those on the

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attached Attendance List.

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The subjects discussed at this meeting are described in the enclosed Meeting

Summary.

It is our opinion that this meeting was beneficial and has provided a better

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understanding of the issues regarding the unscreened containment sump

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penetrations found on the Units 1 and 2 containment sumps.

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In accordance with Section 2.790 of the NRC's " Rules of Practice," Part 2,

Title 10, Code of Federal Regulations, a copy of this letter will be placed in

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the NRC's Public Datument Room.

Should you have any questions concerning this matter, we will be pleased to

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discuss them with you.

Sincerely,

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A. Bill Beach, Director

Division of Reactor Projects

Enclosure:

Meeting Summary w/ attachments

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(see next page)

9312070015 931130

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Entergy Operations, Inc.

ATTN: Harry W. Keiser, Executive

Vice President & Chief Operating Of t icer

P.O. Box 31995

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Jackson, Mississippi

39286-1995

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Entergy Operations, Inc.

ATTN: John R. McGaha, Vice President

Operations Support

P.O. Box 31995

Jackson, Mississippi

39286

Wise, Carter, Child & Caraway

ATTN:

Robert B. McGehee, Esq.

P.O. Box 651

Jackson, Mississippi

39205

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Honorable C. Doug Luningham

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County Judge of Pope County

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Pope County Courthouse

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Russellville, Arkansas 72801

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Winston & Strawn

ATTN: Nicholas S. Reynolds, Esq.

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1400 L Street, N.W.

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Washington, D.C.

20005-3502

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Arkansas Department of Health

ATTN: Ms. Greta Dicus, Director

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Division of Radiation Control and

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Emergency Management

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4815 West Markham Street

Little Rock, Arkansas 72201-3867

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B&W Nuclear Technologies

ATTN: Robert B. Borsum

Licensing Representative

1700 Rockville Pike, Suite 525

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Rockville, Maryland 20852

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Admiral Kinnaird R. McKee, USN (Ret)

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214 South Morris Street

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0xford, Maryland 21654

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ATTN: Charles B. Brinkman

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Manager, Washington

Nuclear Operations

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12300 Twinbrook Parkway, Suite 330

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Rockville, Maryland 20852

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MEETING SUMMARY

Licensee:

Entergy Operations, Inc.

Facility:

Arkansas Nuclear One

License No.-

DPR-51

NPf-6

Docket No.:

50-313

50-368

Subject:

Enforcement Conference Regarding Unscreened Containment Sump

Penetrations

The licensee discussed the sequence of events relative to the discovery of

unscreened containment sump penetrations, their response to the condition, the

results of their root cause evaluation and self-assessment, corrective

actions, the safety significance of the condition, and their perspective on

possible enforcement action.

Attachments:

1.

Attendance List

2.

Licensee Presentation (NRC distribution only)

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ATTACHMENT I

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ATTENDANCE LIST

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Attendance at the Enforcement Conference between Entergy Operations, Inc. and

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NRC on November 23, 1993, in the Region IV Office, Arlington, Texas *

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Enteroy Operations. Inc.

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C. Anderson, Operations Manager, Unit 2

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B. Greeson, Acting Manager, Mechanical / Civil / Structural Engineering

M. Huff, Supervisor, Mechanical Engineering

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R. King, Acting Director, Licensing

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R. Lane, Director, Design Engineering

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J. Miller, Supervisor, Nuclear Engineering

J. Vandergrift, Plant Manager, Unit 1

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G. Woerner, Supervisor, Mechanical Engineering

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J. Yelverton, Vice President, Operations

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NRC

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R. Azua, Resident Inspector, Fort Calhoun Station

W. Beckner, Project Directorate IV-1, Office of Nuclear Reactor

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Regulation (NRR)

W. Brown, Regional Counsel

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S. Collins, Director, Division of Reactor Safety (DRS)

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T. Gwynn, Acting Director, Division of Reactor Projects (DRP)

K. Kennedy, Project Engineer, DRP

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J. Milhoan, Regional Administrator

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T. Stetka, Chief, Project Section D, DRP

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T. Alexion, Project Manager, NRR

R. Wise, Acting Enforcement Officer

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ATTACHMENT 2

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OPENING REMARKS

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JERRY YELVERTON

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Vice President

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OVERVIEW of PRESENTATION

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Acting Director

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AGENDA

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OPENING REMARKS

JERRY YELVERTON

Vice President Operations

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INTRODUCTION

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PRESENTATION OVERVIEW

RICK KING

Acting Director Licensing

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OPERATIONS OVERVIEW

JIM VANDERGRIFT

Unit 1 Plant Manager

CRAIG ANDERSON

Unit 2 Operations Manager

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III.

ROOT CAUSE EVALUATION

JIM VANDERGRIFT

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CORRECTIVE ACTIONS

Plant Manager Unit 1

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ENGINEERING EVALUATION

RICK LAh5

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Director Design Engineering

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SAFETY SIGNIFICANCE

JAY MILLER

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Supervisor Nuclear Engineering

VI.

ANO ENFORCEMENT

RICK KING

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PERSPECTIVE

Acting Director Licensing

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VII.

CONCLUSION

JERRY YELVERTON

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Vice President Operations

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OPERATIONS OVERVIEW

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Plant Manager Unit 1

CRAIG ANDERSON

Operations Manager Unit 2

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22 UNSCREENED CURB DRAINS

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5 OPENINGS AROUND CONDUIT PENETRATIONS

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SYSTEM OVERVIEW

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HOWEVER MULTIPLE SUCCESS PATHS AVAILABLE TO

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OPERATOR TO MAINTAIN CORE COOLING

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SELF IDENTIFIED BY QUESTIONING ATTITUDE OF ANO

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OCTOBER 1,1993, CONDITION REPORT (CR) WAS

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WRITTEN TO DOCUMENT CONDITION

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PERFORMED

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DESIGN INFORMATION

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PAST OPERABILITY FOR UNIT 1 WAS ASSESSED PER

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PROCEDURE 1000.104 AND RESULTED IN A 10CFR50.72

NOTIFICATION TO THE NRC ON OCTOBER 14,1993

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DESIGN DRAWING REVEW COULD NOT VERIFY

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SUMP DECLARED INOPERABLE, ENTERED TS 3.0.3 AT

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1719 HOURS ON OCTOBER 22,1993

ENFORCEMENT DISCRETION GRANTED AT 2015 HOURS

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ON OCTOBER 22,1993

REPORTED PER 10CFR50.72(2)(iii) ON OCTOBER 22,1993

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POTENTIAL HPSI AND CS SYSTEM DEGRADATION

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WHILE ON SUMP RECIRCULATION

REPAIRS COMPLETED AND TS 3.0.3 EXITED AT

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CURB DRAINS COVERED WITH DRILLED METAL PLATES

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INSPECT SELECTED DRAINS AND SUMP SCREEN

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DRAINS

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IMhEDIATE REPAIRS MADE TO DESIGN DEFICENCIES

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UNSCREENED OPENINGS

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ROOT CAUSE EVALUATION

UNIT 1

,

l

ORIGINAL DESIGN, CURB DRAINS AND

-

l

FLOOR DRAIN OPENINGS ABOVE SCREENS

MAY 1973, NEW DESIGN INSTALLATION

-

INCREASED SCREEN AREA AND RAISED

SCREEN; ALLOWED CURE DRAINS AND

.

FLOOR DRAINS TO BE OPENED TO SUMP

l

UNSCREENED

OPENINGS AROUND CONDUIT WERE DUE

-

TO LACK OF CONSTRUCTION DETAILS

ROOT CAUSE FOR DESIGN INSTALLATION

DEFICIENCIES

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!

INADEQUATE DESIGNER REVIEW OF

-

'

ASSOCIATED DOCUMENTS PRIOR TO

I j

INSTALLING THE SUMP SCREEN

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ASSEMBLY MODIFICATION DURING

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CONSTRUCTION

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TEAR IN SCREENS

1

ROOT CAUSE EVALUATION

UNIT 1

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NOT READILY APPARENT FROM OUTSIDE

-

SUMP DUE TO POOR LIGHTING AND THE

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SCREEN ON INSIDE OF GRATING

i

MOST LIKELY OCCURRED DURTNG

1

-

MAINTENANCE OR MODIFICATION

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ACTIVITIES

RECENT UNIT 1 EMPHASIS ON SUMP

!

-

INSPECTIONS HAVE FOCUSED PRIMARILY

ON CLEANLINESS, NOT SCREEN INTEGRITY

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!

PROBABLE CAUSE

!

t

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THE TEARS IN THE SUMP SCREENS WERE

-

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MOST LIKELY CAUSED BY

MAINTENANCE / MODIFICATION

!

WORK BY PERSONNEL UNAWARE OF

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DESIGN BASIS REQUIREMENTS

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UNSCREENED OPENINGS

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ROOT CAUSE EVALUATION

UNIT 2

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OPENINGS BELOW GRATING NOT SHOWN

-

1

ON DESIGN DRAWING; THEY ARE

BELIEVED TO BE AN ORIGINAL FIELD

'

MODIFICATION INSTALLED PRIOR TO 1978

ORIGINAL CONSTRUCTION PERSONNEL

-

,

MAY NOT HAVE BEEN AWARE OF DESIGN

,

REQUIREMENTS OF SUMP, (I.E. 3/32"

,

MAXIMUM SCREEN OPENING)

,

VISUAL APPEARANCE OF OPENINGS

-

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APPEAR TO BE DESIGN FEATURES

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ROOT CAUSE

'

THIS DISCREPANCY WAS MOST LIKELY

-

!

DUE TO A CONSTRUCTION INSTALLATION

!

ACTIVITY PERFORMED WITHOUT DESIGN

!

l

CONCURRENCE. THIS ALLOWED DESIGN

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REQUIREMENTS TO BE EXCLUDED FROM

!

THE INSTALLED CONFIGURATION.

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CONTRIBUTING FACTORS

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UNIT 1

FAILURE TO PERFORM COMPLETE AND'

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THOROUGH REVIEW OF-IN 89-77

REGARDING SUMP SCREEN INTEGRITY AND

CONFIGURATION

UNIT I OPERATIONS AND QC SUMP

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INSPECTIONS FOCUSED ON DEBRIS

,

AND NOT SCREEN INTEGRITY

'

COMMON

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UNSCREENED OPENINGS APPEAR TO BE

-

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DESIGNED CONFIGURATIONS

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SUMP LOCATION IS IN ONE OF THE LEAST

!

-

'

READILY ACCESSIBLE LOCATIONS OF

REACTOR BUILDINGS

,

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HISTORICALLY HIGH RADIATION AREA

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-

.

PLANT PERSONNEL MOST LIKELY TO FIND

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CONCERNS WITH SUMP HAVE LEAST

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KNOWLEDGE OF DETAILED DESIGN

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REQUIREMENTS

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-

.-

-

.

-

CORRECTIVE ACTIONS

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IMMEDIATE

UNIT 1

i

INSTALLED STEEL PLATE / SCREEN MESH ON

i

-

CURB DRAINS

.

SCREENED CONDUIT PENETRATIONS

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REPAIRED SCREEN TEARS

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SCREENED DRAINS

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MODIFIED DRAINS / HEADERS

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CURB DRAINS

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_ _ _ _ _ _ _ _ _ _ - _

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CORRECTIVE ACTIONS

BROAD BASED

ASSESS OTHER VULNERABLE COMPONENTS

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COMPONENTS IDEN 11HED IN ESF SYSTEMS WHOSE

-

,

FAILURES COULD CAUSE FAILURE OF BOTH ESF

TRAINS

EVALUATE COhPONENTS IDENTIFED ABOVE BY:

-

I

REVEWING DESIGN REQUIREhENTS FOR THE

-

COMPONENTS

PERFORMING AS-BUILTINSPECTION

-

EVALUATING OPERATING PRACTICES,

-

MAINTENANCE AND SURVEILLANCES

REVEW DESIGN BASIS RECONSTITUTION PROJECT

-

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DISCREPANCY PRIORITIZATION PROCESS FOR

ADEQUACY AND POTENTIAL UPGRADES.

DESIGN BASIS RECONSTITUTION PROJECT

-

HIGH AND hEDIUM PRIORITY DISCREPANCES

WERE REVEWED TO ENSURE NO IhPACT ON

PLANT SAFETY

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CORRECTIVE ACTIONS

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(CONTINUED)

ASSESS PROCESS TO HANDLE INFORMATION NOTICES

INDEPENDENT PROGRAM ASSESSMENT OF THE

'

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CURRENT NRC INFORMATION NOTICE EVALUATION

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PROCESS IMhEDIATELY PERFORMED. (REVEWED 17

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INFORMATION NOTICES)

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INDEPENDENT ASSESSMENT CONCLUDED THAT:

-

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GOOD PROCESS CONTROLS IN PLACE

-

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PERFORMED A DETAILED REVEW OF RANDOMLY

!

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SELECTED LN.s BACK TO 1988

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TWO POPULATION SIZES ESTABLISHED

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1988 TO AUGUST 1990 (33)

-

.

-

AUGUST 1990 TO PRESENT (50)

MIL STD 105D USED TO SELECT A RANDOM SAh@LE

-

.

OF 83 I.N. EVALUATIONS TO ACHEVE A 95%

'

CONFIDENCE LEVEL

!

.

,

RESULTS INDICATE THAT NO SIGNIFICANT DEFICENCES

i

-

WERE IDENTIFED BY THE REVIEWS

!

SCREEN AND REVEW INFORMATION NOTICES AND

-

EVALUATIONS PRIOR TO 1991 FOR APPLICABILITY AND

POTENTIAL IMPACT TO SAFETY

!

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CORRECTIVE ACTIONS

SUMMARY

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DESIGN INSTALLATION DEFICIENCES OCCURRED

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DURING CONSTRUCTION

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SELF IDENTIFICATION DUE TO QUESTIONING ATTITUDE

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CONTINUE TO ENCOURAGE INDIVIDUALS TO IDENTIFY

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PROBLEMS, REWARDING THEM FOR THEIR EFFORTS

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COMPLETED

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CONTAINMENT AT POWER TO INSPECT SUMP

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IDENTIFY AND EVALUATE COMPONENTS IN ESF

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SYSTEMS WHOSE FAILURES COULD CAUSE FAILURE OF

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!

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BASIS REQUIREMENTS (VERIFIED BY INTERN!,L AND

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EXTERNAL ASSESSMENTS OF PROCESS)

THOROUGH ROOT CAUSE ANAIXSIS

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ACTIONS WERE TIMELY, COMPREHENSIVE, AND

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EFFECTIVE

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UNSCREENED CONDUIT / PIPE OPENINGS (4 TOTAL)

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DEBRIS ASSESSMENT

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OBJECTIVE

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ASSESS THE TYPE, SIZE AND QUANTITY OF DEBRIS

i

-

THAT COULD HAVE BEEN TRANSPORTED INTO THE

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PRIOR TO OCTOBER 22,1993, FOR UNIT 2

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EVALUATION APPROACH

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-

AVAILABLE ASSESSED

!

REG GUIDE 1.82 AND NUREG-0897 UTILIZED

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ALDEN RESEARCH LAB ASSISTED AND VALIDATED

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METHODS / ASSUMPTIONS

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DEBRIS ASSESSMENT

(CONTINUED)

TYPES OFMATERIALS ANALYZED

HEAVY MATERIAL

-

1

-

CONCRETE CHIPS

'

-

WELD ROD

,

NAILS

-

WIRE MESH

-

FLASHLIGHT

-

RUBBER CYLINDERS

-

,

ETC.

!

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LIGHT MATERIAL

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FIBERGLASS INSULATION

-

RAGS

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TAPE

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PAPER

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PLASTIC

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ETC.

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DEBRIS TRANSPORT

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ASSESSMENT

UNIT 1 AND 2

HEAVY MATERIAL

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HEAVY MATERIAL REQUIRES TRANSPORT

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VELOCITY GREATER THAN 4 FT/SEC

SUMP VELOCITY PROFILE ILLUSTRATES THAT

-

TRANSPORT POTENTIALIS LOW DUE TO LOW

VELOCITY

VELOCITY PROFILES AT SUCTIONINLET

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1D = 1.48 FT/SEC (UNIT 1)

-

ID = 0.31 FT/SEC (UNIT 2)

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(LESS THAN REQUIRED FOR FINE SAND 1.5 FT/SEC)

ALONG SUMP FLOOR NEAREST TO PIPE INLET

-

VELOCITIES WILL NOT TRANSPORT HEAVY

MATERIAL

~

-

< 0.48 FT/SEC (UNIT 1)

< 0.10 FT/SEC (UNIT 2)

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ANY HEAVY MATERIAL ENTERING THE SUMP WILL

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ENTER PRIOR TO RECIRCULATION, SETTLE AND

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DEBRIS TRANSPbRT

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ASSESSMENT

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UNIT 1

-

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LIGHT MATERIAL

>

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(WORST CASE - LBLOCA) LIGHT WEIGHT MISC DEBRIS

i

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BOUNDED BY FIBROUS INSULATION INSTALLED IN 1990

!

4

(IR9)

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i

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!

-

SG, PRESSURIZER AND HOT LEG

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VOLUME OF INSULATION DEBRIS 109 CU FT

-

INSULATION SPREADS OUT ON ELEV 336 INSIDE "D" RING

l

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!

-

TRANSPORT OCCURS WITHIN 15 FT OF SUMP

-

t

TOTAL VOLUhE = 30 CU FT

-

1

INSULATION HAS A SPECIFIC GRAVITY = 1.08 AND WILL

-

REMAIN ON THE FLOOR

!

OPEN CURB DRAINS ALLOW THE 30 CU FT TO ENTER

-

ASSESSMENT CONSERVATISMS

,

INSULATION EVALUATION

-

ALL DISLODGED INSULATION ASSUMED TO REACH

-

'

BASEhENT FLOOR AND REMAIN IN "D" RING AREA

!

INSULATION ENCAPSULATED IN hETAL

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DETAIL

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COMPONENT ASSESSMENT

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IDENTIFIED ALL COMPONENTS IN THE

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UNIT 1 LPI, HPI AND RBS SYSTEMS DURING

SUMP RECIRCULATION

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.

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IDENTIFIED ALL COMPONENTS IN THE

-

UNIT 2 HPSI, LPSI, AND CS SYSTEMS

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DURING SUMP RECIRCULATION

EVALUATED WHICH COMPONENTS WOULD

!

-

BE LMPACTED BY DEBRIS IN SUMP

.

CONTACTED VENDORS TO DETERMINE THE

-

,

IMPACT OF THE DEBRIS ON COMPONENTS

AFFECTED

BASED UPON VENDOR INTERFACE,

-

DOCUMENT RESEARCH, TESTING, ETC.

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EVALUATED PERFORMANCE OF

INDIVIDUAL COMPONENTS

DETERMINED PROBABILITY OF OPERATION

-

FOR COMPONENTS DURING SBLOCA,

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MBLOCA AND LBLOCA

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ENGINEERING EVALUATION

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SUMMARY

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PROMPT AND EFFECTIVE IMMEDIATE CORRECTIVE

-

ACTIONS TAKEN TO RESTORE SUMP INTEGRITY

DEBRIS AND COMPONENT ASSESShENTS IDENTIFIED

-

LIKELIHOOD OF OPERATION FOR COMPONENTS DURING

SBLOCA, MBLOCA AND LBLOCA

HEAVY MATERIAL DOES NOT TRANSPORT, ONLY LIGHT

-

MATERIAL TRANSPORTS

COMPONENT DEGRADATION MORE LIKELY TO OCCUR

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RATHER THAN A LOSS OF FUNCTION

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Supervisor Nuclear Engineering

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SAFETY SIGNIFICANCE

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EVALUATION

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PRIMARY OBJECTIVE:

DETERMINE THE IMPACT OF DEBRIS ENTERING

THE SUMP THROUGH UNSCREENED FLOW

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PATHS ON THE ABILITY OF ENGINEERED

!

SAFEGUARD FEATURES TO PERFORM MIR

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REQUIRED SAFETY FUNCTIONS

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RESULTS

DUE TO LIMITED COMPONENT IMPACT

POTENTIAL, CORE DAMAGE FREQUENCY DID

NOT EXCEED THE NRC SEVERE ACCIDENT

POLICY STATEMENT SAFETY GOAL

DUE TO THE EXPECTED AVAILABILITY OF

'

CONTAINMENT SYSTEMS, CONTAINMENT

4

FAILURE WAS UNLIKELY, MINIMIZING THE

'

POTENTIAL FOR OFFSITE RELEASE

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SAFETY. SIGNIFICANCE

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EVALUATION

KEY ELEMENTS

IDENTIFY LONG-TERM CORE COOLING

-

1

SUCCESS PATHS TO:

MAINTAIN THE CORE COVERED

-

REMOVE DECAY HEAT

-

ASSESS THE IMPACT OF DEBRIS ON

-

ENGINEERED SAF5 GUARDS COMPONENTS,

SYSTEMS AND STRUCTURES

ASSESS CORE DAMAGE AND CONTAINMENT

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FAILURE RISK SIGNIFICANCE

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RISK SIGNIFICANCE

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UTILIZED SCENARIO SPECIFIC EVENT

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TREES TO ASSESS MULTIPLE LONG-TERM

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CORE COOLING SUCCESS PATHS

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CONTAINMENT FAILURE PROBABILITY

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INCREASE:

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UTILIZED SCENARIO SPECIFIC EVENT TREE

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CORE DAMAGE RESULTS

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UTILIZED IPE CONTAINMENT RESPONSE

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ANALYSIS TO ASSESS CONTAINMENT

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PERFORMANCE

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KEY CORE DAMAGE ASSESSMENT

ELEMENTS

DEBRIS GENERATION AND TRANSPORT

POTENTIAL

DEBRIS IMPACT ON REQUIRED COMPONENTS

UNIT 1

LPI/DHR COOLER OUTLET VALVES

-

LPI, RBS AND HPI PUMPS

-

RBS NOZZLES

-

FUEL ASSEMBLIES

-

UNIT 2

HPSI THROTTLE VALVES

-

HPSI, CS AND LPSI PUMPS

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CS NOZZLES

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FUEL ASSEMBLIES

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OPERATOR ABILITY TO UTILIZE MULTIPLE

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_

LONG-TERM CORE COOLING SUCCESS PATHS

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KEY CONTAINMENT FAILURE

ASSESSMENT ELEMENTS

UNIT 1

CONTAINMENT FAILURE IS UNLIKELY WITH

ANY ONE OF:

TWO LPI/DHR COOLER TRAINS

-

TWO RB COOLER TRAINS

-

NO DEBRIS IMPACT ON RB COOLERS

MINIMAL DEBRIS IMPACT ON RB SPRAY

UNIT 2

CONTAINMENT FAILURE IS UNLIKELY willi

ANY ONE OF:

'

TWO CS TRAINS

-

TWO CONTAINMENT COOLER TRAINS

-

NO DEBRIS IMPACT ON CONTAINMENT

COOLERS

MINIMAL DEBRIS IMPACT ON CONTAINMENT

SPRAY

1

.

RISK SIGNIFICANCE SUMMARY

li

ANO-l&2 CORE DAMAGE FREQUENCY INCREASE

2.00E44

1SOE44

1.60E-04

1.40E44

NRC Sofoty Goal

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ANO-1

ANO-2

CORE DAMAGE RESULTS IMPLY REDUCED

MARGIN, BUT DID NOT EXCEED THE NRC SEVERE

ACCIDENT POLICY STATEMENT SAFETY GOAL

P

DUE TO THE EXPECTED AVAILABILITY OF

CONTAINMENT SYSTEMS, CONTAINMENT

FAILURE WAS UNLIKELY, MINIMIZING THE

POTENTIAL FOR OFFSITE RELEASE

,

.

-

.

._*

SAFETY SIGNIFICANCE

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..

MITIGATING FACTORS

.

HEAVY MATERIAL TRANSPORT

-

,

MECHANISMS ARE SUCH THAT HEAVY

l

MATERIAL WILL NOT BE TRANSPORTED

TO ENGINEERED SAFEGUARD FEATURES

,

ONLY A SMALL PORTION OF BREAK

-

LOCATIONS PRODUCE TRANSPORTABLE

FIBROUS DEBRIS (UNIT 1 <20%, UNIT 2 <1%)

!

UNSCREENED FLOW PATHS INTO THE SUMP

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ARE A SMALL FRACTION OF THE

,

TOTAL SCREENED SUMP FLOW AREA

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(UNIT 1 <4%, UNIT 2 <0.2%)

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THE ACCIDENTS LIKELY TO PRODUCE

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-

DEBRIS AND DEBRIS TRANSPORT (LBLOCA)

,

ARE UNLIKELY TO OCCUR AND LIKELY TO

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BE DETECTED PRIOR TO OCCURRENCE,

ALLOWING A CONTROLLED SHUTDOWN

'

!

THE MOST LIKELY ACCIDENTS (SBLOCA)'

-

PRODUCE MINIMAL DEBRIS OR DEBRIS

'

--

TRANSPORT AND SHOULD BE TERMINATED

ON DHIUSDC WITH NO, OR MINIMAL, SUMP

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-

RECIRCULATION

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_

>

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.-

-

,- ,

-

--

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-

SAFETY SIGNIFICANCE

..

MITIGATING FACTORS

MULTIPLE MEANS ARE AVAILABLE FOR

-

POST-ACCIDENT LONG-TERM CORE

COOLING IF SUMP RECIRCULATION IS

REQUIRED

LOWER DECAY HEAT LOADS EXIST FOR

-

LONG-TERM CORE COOLING, RESULTING IN

MARGIN FOR POTENTIAL FLOW

DEGRADATION

LIMITED POTENTIAL EXISTS FOR DEBRIS

-

,

INDUCED FAILURE OF MOST STRUCTURES,

SYSTEMS OR COMPONENTS

DUE TO THE EXPECTED AVAILABILITY OF

-

CONTAINMENT SYSTEMS, CONTAINMENT

INTEGRITY SHOULD BE MAINTAINED,

MINIMIZING THE POTENTIAL OF OFFSITE

DOSE CONSEQUENCES

-.

L

.

-.

- -

SAFETY SIGNIFICANCE

~

SUMMARY

'

DESIGN INSTALLATION DEFICIENCIES

^

POSED SAFETY QUESTIONS

-

WERE ASSESSED FOR SAFETY

-

SIGNIFICANCE USING CONSERVATIVE BEST

JUDGEMENT

'

MORE LIKELY TO RESULT IN A

-

DEGRADATION RATHER THAN A LOSS OF

'

SAFETY FUNCTION

RESULTED IN A REDUCTION OF SAFETY

-

MARGIN, BUT DID NOT RESULT IN AN

INCREASE IN CORE DAMAGE FREQUENCY

ABOVE THE NRC SEVERE ACCIDENT

POLICY STATEMENT SAFETY GOAL

,

DID NOT REPRESENT AN UNDUE RISK TO

-

PUBLIC HEALTH AND SAFETY

-

OM

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ANO ENFORCEMENT

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PERSPECTIVE

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RICK KING

Acting Director Licensing

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SEVERITY OF ISSUE

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REQUEST FOR EXERCISE

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ADJUSTMENT FACTORS

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SEVERITY LEVEL

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SUPPLEMENT I- REACTOR OPERATIONS

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FOR THE EXAMPLES OF DESIGN INSTALLATION DEFICIENCIES

(LE., UNIT 1, UNSCREENED PENETRATIONS AND CURB DRAINS;

CURB DRAINS FOR UNIT 2), CRITERION C.2 OF SUPPLEMENT I

!

APPEARS TO APPLY:

A SAFETY SYSTEM BEING DEGRADED TO THE EXTENT

-

THAT A DETAILED EVALUATION WOULD BE REQUIRED

l

TO DETERMINE ITS OPERABILITY

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SAFETY SIGNIFICANCE

>

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COMPONENT DEGRADATION INTRODUCED AN

~

'

-

UNDESIRABLE INCREASE IN RISK BUT DID NOT

l

REPRESENT AN UNDUE RISK TO PUBLIC HEALTH AND

'

SAFETY.

.

-

THE CALCULATED INCREASE IN RISK IS BELOW THE NRC

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-

SAFETY GOAL

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.

ANO'S CONDITION WOULD NOT HAVE RESULTED IN

-

A LOSS OF SAFETY FUNCTION

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SEVERITY LEVEL

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SUPPLEMENT I- REACTOR OPERATIONS

REGULATORY SIGNIFICANCE

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THE FINDINGS WERE NOT REPRESENTATIVE AND ARE

-

INCONSISTENT WITH ANO'S GOOD PERFORMANCE

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ANO PERSONNEL DEMONSTRATED A QUESTIONING

,

-

ATTITUDE

l

.,

ONGOING DESIGN BASIS REVIEW INITIATIVES WILL ENSURE

-

THE IDENTIFICATION OF DESIGN CONTROL DEFICIENCIES '

1

IN AREASONABLE AND PROMPT MANNER

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RECOMMENDATION:

SEVERTTY LEVEL III

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-

EXERCISE OF DISCRETION

BASES FOR DISCRETION:

ACCORDING TO SECTION VII. B. 4 OF THE NRC ENFORCEMENT

!

POLICY, " VIOLATIONS INVOLVING OLD DESIGN ISSUES," THE

.

PURPOSE OF ENFORCEMENT DISCRETION FOR WIS TYPE OF

.

ISSUE "IS TO PLACE A PREMIUM ON IDENTIFY:

DESIGN,

ENGINEERING, /MD INSTALLATION VIOLATIONL BEFORE

,

AFFECTED SYSTEMS ARE CALLED UPON TO WORK"

SELF IDENTIFIED

-

,

QUESTIONING ATTITUDE DEMONSTRATED BY

!

-

PERSONNEL PERFORMING SUMP RELATED WORK

!

SELF-CRITICAL CULTURE IS A WAY OF DOING

-

BUSINESS AT ANO

,

IMMEDIATELY DOCUMENTED BY THE ANO

-

CORRECTIVE ACTION SYSTEM

!

ROOT CAUSE PROMPTLY INVESTIGATED AND

-

IDENTIFIED

,

.

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I

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-.

-

.

on e.

EXERCISE OF DISCRETION

(Continued)

!

BASES FOR DISCRETION: (Continued)

.

IMMEDIATE AND COMPREHENSIVE CORRECTIVE ACTIONS

-

,

THOROUGH ROOT CAUSE ANALYSIS

-

TIMELY AND EFFECTIVE

BROADLY-FOCUSED

-

SCOPE OF ACTIONS RANGED FROM ASSESSING

-

OTHER COMPONENTS TO REASSESSING

i

THE DESIGN CONFIGURATION DOCUMENTATION

PROCESS AS WELL AS THE PROCESS FOR

!

ADDRESSING NRC INFORMATION NOTICES

ALL DESIGN INSTALLATION DEFICENCES WOULD NOT

-

HAVE BEEN IDENTIFIED BY ROUTINE LICENSEE EFFORTS

SUCH AS:

OPENINGS APPEAR TO BE DESIGN FEATURES AND

-

COULD BE EASILY OVER LOOKED WITHOUT A

CONCENTRATED EFFORT DURING QA OR

SURVEILLANCE ACTIVITIES (AS EVIDENCED BY

,

WALKDOWNS, MAINTENANCE / MODIFICATIONS

ACTIVITES AND REGULATORY INSPECTIONS)

j

IT IS NOT REASONABLE TO CONCLUDE THAT IN 89-77

'

-

.

WOULD HAVE CAUSED LICENSEES TO CONDUCT A

DETAILED AS-BUILT DESIGN REVEW OF THE SUMP

SCREENS

.

4

f

.

....

EXERCISE OF DISCRETION

(Continued)

BASES FOR DISCRETION: (Continued)

ISSUEilS GREATER THAN THREE (3') YEARS OLD AND

NOT LINKED TO PRESENT PERFORMANCE

i

BASED ON INFORMATION TO DATE, THE SCREEN

-

DEFICIENCIES OCCURRED DURING PLANT

CONSTRUCTION.

.

INCONSISTENT WITH ANO'S GOOD PERFORMANCE

-

RECOMMENDATION:

.

EXERCISE DISCRETION

-

REFRAIN FROM ISSUING A NOTICE OF VIOLATION

-

,

AND CIVILPENALTY

i

,

e

i

1

e

-

- - -

- - . . -

-

.

. . .

CIVIL PENALTY

ADJUSTMENT FACTORS

SHOULD THE NRC CONCLUDE THAT THIS CONDITION

WARRANTS A CIVIL PENALTY, THE FOLLOWING CIVIL

PENALTY ADJUSTMENT FACTORS APPEAR TO APPLY:

ESCALATION

DURATION

BECAUSE THE DESIGN INSTALLATION DISCREPANCES

-

DID NOT RESULT IN A CONDITION OF HIGH ACTUAL

SAFETY SIGNIFICANCE, THE ESCALATION FACTOR FOR

DURATION SHOULD NOT BE CONSIDERED

PRIOR OPPORTUNITY TO IDENTIFY

MAJORITY OF NRC COMMUNICATIONS

-

SPECIFICALLY ADDRESSED DEBRIS CONTROL;

SIMR.ARLY, THE PURPOSE OF I.N. 89-77 WAS TO

ADDRESS HOUSEKEEPING AND INSUFFICENT

SURVEILLANCE OF CONTAINMENT EMERGENCY

RECIRCULATION SUMPS

IT IS NOT REASONABLE TO CONCLUDE FROM IN 89-77

-

THAT A DETAILED AS-BUILT DESIGN REVEW OF THE

SUMP SCREENS WAS INTENDED. RATHER, THE I.N.

FOCUSED ON ENSURING SUMP INSPECTION CRITERIA

WERE PROCEDURALIZED

THEREFORE, ANO DOES NOT BELEVE THE I.N.

-

REPRESENTED A PRIOR OPPORTUNITY TO 1DENTIFY

ALL THE DESIGN INSTALLATION DEFICENCES

i

-

,

'

,

-

CIVIL PENALTY

ADJUSTMENT FACTORS

(Continued)

!

i

MITIGATION

IDENTIFICATION

i

SELF-IDENTIFIED BY ANO

-

QUESTIONING ATTITUDE BY ELECTRICIAN AND

-

SYSTEM / DESIGN ENGINEERING PERSONNEL

!

ANO PERFORMANCE

'

OVERALL PAST PERFORMANCE SHOWS AN

-

IMPROVING TREND

~

LAST CIVIL PENALTY AND LEVEL III NOTICE OF

!

-

VIOLATION WAS APPROXIMATELY 3 YEARS AGO

l

THESE DESIGN INSTALLATION DEFICIENCIES WOULD

-

NOT OCCUR UNDER CURRENT DESIGN CONTROL

'

PRACTICES

i

5

I

!

1

-

t

.

_

,

\\

-

>

!

_

CIVIL PENALTY

,

J

ADJUSTMENT FACTORS

(Continued)

l

t

MITIGATION (Continued)

!

l

ANO PERFORMANCE (CONTINUED)

!

a

't

i

CONDITION IS INCONSISTENT WITH GOOD

!

-

CURRENT DESIGN AND TECHNICAL PERFORMANCE

-)

VERY GOOD PROCESS FOR CONTROLLING

-

DESIGN MODIFICATIONS AND OTHER

l

ENGINEERING ACTIVITIES-

.

!

SAFETY EVALUATIONS OF MODIFICATIONS

!

4

-

ARE WELL PREPARED

i

r

CONSERVATIVE ENGINEERING PRACTICES

i

-

'!

,

EXCELLENT VENDOR TECHNICAL MANUA1

2

-

PROGRAM

,

!

GOOD OPERABILITY DETERMINATIONS

-

,

EXCELLENT OPERATIONS SUPPORT

-

,

SELF ASSESSMENTS DEMONSTRATE ~

-

'

MANAGEhENT ATTENTION TO PERFORMANCE

!

'

i

1

!

_

!

l

-

!

i

4

!

I

-

.

_

-

. - - .

_

. - . - .

.

-

>

.

)

_.

i

-

CIVIL PENALTY

ADJUSTMENT FACTORS

i

(Continued)

!

.

MITIGATION (Continued)

!

CORRECTIVE ACTIONS

!

IMMEDIATELY RESTORED TO AN OPERABLE

I

-

CONDITION

!

BROADLY FOCUSED AND EXTENSIVE

.I

-

i

THOROUGH ROOT CAUSE ANALYSIS

l

-

>

DEMONSTRATED INITIATIVE TO VOLUNTARILY

-

ENTER CONTAINMENT AT POWER TO INSPECT

I

UNIT 2 SUMP INTEGRITY (SUMP AND DRAINS)

TIhELY, COMPREHENSIVE AND EFFECTIVE

-

I

!

f

!

,

I

i

b

l '

l

'

.

_!

'

I

'

I

i

c

. -. -

.-. ..

-

- .. - - -

..

,.

._

.

. .

..

. - .

.

.-

- .

wm

.

I

t

_.

CONCLUSION

i

!

.

OUR EVALUATION OF THIS MATTER CONCLUDES

l

-

THAT A REASONABLE BASIS FOR ENFORCEMENT

f

DISCRETION EXISTS PURSUANT TO SECTION VII.

B. 4 OF THE NRC ENFORCEMENT POLICY -

'

!

RECOMMENDATION:

.

EXERCISE ENFORCEMENT DISCRETION AND

-

REFRAIN FROMISSUING ANOTICE OF

VIOLATION AND A CIVIL PENALTY

!

F

t

,

i

.

I

!

.

!

')

i

'

i

l

1

,

. , , ,

,_ .

.

_ _

.

~

.

-.#

l

-

CONCLUSION

(Continued)

.

,

'

IF THE NRC DOES NOT REFRAIN FROM ISSUING

-

A NOTICE OF VIOLATION, IT APPEARS THAT THE NRC

ENFORCEMENT POLICY PROVIDES AMPLE

JUSTIFICATION FOR COMPLETE MITIGATION OF

THE CIVIL PENALTY

RECOMMENDATION:

'

A SEVERITY LEVEL III NOTICE OF VIOLATION

-

NO CIVIL PENALTY

-

4

,

i

ii

4

i

,

.

L

.

'

l

.

- -

.

,,-

,

.

c

-

,

CONCLUSION

!

[

i

o

JERRY YELVERTON

Vice President Operations

.

F

,

1

I

!

1

-

f

_.

f

ML20058E442

Text

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