IR 05000206/1993014

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Enforcement Conference Rept 50-206/93-14 on 930602.No Violations Noted.Major Areas Inspected:Licensee Analyses of Violations of NRC Requirements Re Unplanned Extremity Exposure Event,As Presented in NRC Insp Rept 50-206/93-06
ML13333A160
Person / Time
Site: San Onofre Southern California Edison icon.png
Issue date: 06/03/1993
From: Nader Mamish, Reese J
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
To:
Shared Package
ML13333A158 List:
References
50-206-93-14-EC, NUDOCS 9306220098
Download: ML13333A160 (48)
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Text

U. S. NUCLEAR REGULATORY COMMISSION

REGION V

EA No.:

93-122 Report:

50-206/93-14 Dockets:

50-206 Licenses:

DPR-13 Licensee:

Southern California Edison Company (SCE)

Irvine, California 92718 Facility:

San Onofre Nuclear Generation Station, Unit 1 Meeting Location:

Region V Office, Walnut Creek, California Meeting Date:

June 2, 1993 Prepared By:

...

'tDt e

N. a sh, Ra ia ecia ist Approved by:

.3/

.-

-

JD Reese, C aci ties Radiological Protection Branch Summary:

Areas Reviewed:

Previously announced enforcement conference, held at the request of NRC Region V, to discuss the licensee's analyses of several apparent violations of NRC requirements related to the unplanned extremity exposure event, as presented in NRC Inspection Report 50-206/93-0 _Results:

The licensee presented their analyses of the event description, corrective actions taken, causes of the apparent violations and weaknesses identified, and overall safety significance. For a copy of the licensee's presentation, see Attachment A to this repor The licensee's presentation demonstrated understanding of the issues involve Corrective actions presented were thorough and technically sound. No additional violations of NRC requirements were identifie PDR ADOCK 05000206 PDR

DETAILS 1. Persons Attending Licensee R. Ashe-Everest, Supervisor, Nuclear Fuel Services J. Ecker, Attorney, Newman & Holtzinger G. Gibson, Supervisor, Onsite Nuclear Licensing P. Knapp, Manager, Health Physics R. Lacy, Nuclear Department Manager, San Diego Gas & Electric W. Marsh, Assistant Manager, Nuclear Regulatory Affairs H. Ray, Senior Vice President, Nuclear J. Reust, General Foreman, Health Physics R. Rosenblum, Manager, Nuclear Regulatory Affairs S. Schofield, Supervisor, Health Physics Engineering M. Short, Manager, Site Technical Services NRC M. Blume, Regional Attorney L. Carson, Radiation Specialist H. Chaney, Senior Radiation Specialist M. Cillis, Senior Radiation Specialist B. Faulkenberry, Acting Regional Administrator R. Huey, Regional Enforcement Officer N. Mamish, Radiation Specialist J. Reese, Chief, Facilities Radiological Protection Branch S. Richard, Deputy Director, Division of Reactor Safety and Projects R. Scarano, Director, Division of Radiation Safety and Safeguards (DRSS)

C. VanDenburgh, Chief, Reactor Projects Branch F. Wenslawski, Deputy Director, DRSS 2. Enforcement Conference Overview The individuals listed in Section 1, above, met on June 2, 1993, to discuss the licensee's analysis of the problems related to the unplanned extremity exposure event, and identified in NRC Inspection Report 50 206/93-0 Mr. J. Reese outlined the apparent violations to be discusse The violations included: (1) the failure to survey, as required by 10 CFR 20.201(b), to ensure that the extremity limits in 10 CFR 20.101 were not exceeded; (2)

two examples of failure to follow radiation protection procedures, as required by Technical Specification (TS) 6.8.1; and (3)

the failure to instruct workers of the precautions and procedures to minimize exposure to radioactive materials, as required by 10 CFR 19.1 Following Mr. Reese's review, Mr. R. Scarano discussed the safety significance of the apparent violations, and asked the licensee to address specific issues regarding the licensee's view of the event's significance (whether this was an isolated event or a programmatic breakdown), adequacy of the tailboard (formal pre-job briefing), the improper placement of the Electronic Alarming Dosimeter (PD-i), and the

licensee's interpretation of the term "continuous health physics coverage" used in their RE The meeting progressed to a detailed discussion of the event descriptio The licensee presented its understanding of the problems encountered during the event, followed by a detailed discussion of the stages of work and the causes of the identified problems. The licensee's handout and slides are included as Attachment A to this repor. Specific Points of Discussion In the course of the licensee's presentation, several points received particular attention:

a. Overall Safety Significance The licensee noted several points related to the safety significance of the apparent violations. Regarding the regulatory dose limits, the licensee noted that the extremity dose received by the worker was well below the regulatory limit, even using a conservative calculation to estimate the dos The licensee's defense in depth program; as demonstrated by the intervention of the exposed individual's co-workers, by adequate controls such as pre-job surveys and workers training, and by the general foreman's oversight; was in place to prevent a substantial potential to exceed regulatory limits. The licensee stated that its Radiation Safety Program is characterized by diligence and attention to detail, and that this was an isolated event, not representative of its consistent excellent SALP [Systematic Assessment of Licensee Performance] performanc b. Specific NRC Concerns The licensee acknowledged that communications between the refueling and health physics personnel could have been better, as noted in the inspection report. The licensee emphasized, however, that it has implemented corrective actions to improve communications, including a new procedure and training for planning jobs, and communication training that would be added to the annual retraining and contractor Health Physics (HP) entrance trainin Additionally, the licensee acknowledged the misunderstanding by the HPT of what constitutes "continuous health physics coverage" and added that more extensive and practical guidance would be provided and established as a procedur. Corrections to NRC Inspection Report 50-206/93-06 One error was noted during the enforcement conference. This error was in the 6th paragraph on page 1 The paragraph should state:

"Continuous coverage is defined as the HP Technician having direct visual contact at all times during the work evolution. Remote video/audio gear may be used. If the REP requires continuous coverage, and continuous coverage is not provided, exit the work area and contact HP."

5. SCE's Analysis of NRC Findings The licensee agreed with the NRC's findings regarding the ineffective communications and judgement, and the two examples of procedural violations. However, the licensee questioned the NRC's view of the

"failure to survey" and the "failure to provide instruction to workers" violation The licensee felt that the "failure to survey" violation was not warranted because the health physics technician was not present when the worker managed to dislodge the object out of the upender basket and subsequently handled it. The "failure to provide instruction to workers" violation was also unwarranted according to SCE because the alarming dosimeter (PD-1) was not used as the primary means for measuring radiation exposure (i.e., thermoluminescent dosimeters are the means for measuring radiation). The licensee added that since a non-alarming dosimeter (i.e., pocket ionization chamber) could have been used instead of a PD-i, the alarming function of the dosimeter was a secondary protective measure, and thus a violation was not warrante Mr. Scarano acknowledged the licensee's remarks and stated that the NRC would consider their comments in evaluating these apparent violation NRC ENFORCEMENT CONFERENCE June 2,1993 SOu a

San Onofre Nuclear Generating Station

NRC ENFORCEMENT CONFERENCE PRESENTATION OUTLINE EVENT DESCRIPTION R. M. Rosenblum EVENT ANALYSIS P. J. Knapp REGULATORY ASSESSMENT R. M. Rosenblum

EVENT DESCRIPTION R. M. Rosenblum

EVENT DESCRIPTION DOSE SUMMARY PROBLEMS STAGES OF WORK CAUSES

WORKER DOSE SUMMARY Whole Body Extremities (mRem)

(mRem)

Actual Exposure 157 3300 *

Planned and Authorized 250 Not Limiting Exposure Regulatory Limit 3000 18750

Calculated Extremity Exposure from Object was 2640 mRem

PROBLEMS

-

Self Reading Dosimeter Incorrectly Located

-

HP Tech and Worker Separated

-

Work Evolved to Exceed Scope Discussed in Tailboard

  • Object Dislodged

-

Object Handled

-

Object Handling not Immediately Reported

STAGES OF WORK PLANNING INITIAL ACTIVITIES UPPER CAVITY LOWER CAVITY RE-ENTRY EVALUATION AND RESTART FOLLOWUP

PLANNING

-

REP Generated for Defueling Check-out (Friday 0800-1800)

-

Problem Noted During Check-out

-

Joint Refueling/HP Planning

  • Phone Call
  • Briefing
  • Tailboard
  • Pre-job Briefing at Work Site

HP Tech did not Identify Misplaced Self Reading Dosimetry

  • Coordination of Support

INITIAL ACTIVITIES

-

Worker/HP Tech Enter Lower Cavity (LC)

  • HP Tech Confirms Radiological Conditions Debris Noted on Floor

-

Worker Installs Shielding

-

Worker Operates Upender to ID Interference

  • Fuel Assembly too High in Basket

-

Remove Assembly & Inspect Basket

  • Continuous Coverage Verifies Basket Readings
  • Co-worker in Upper Cavity (UC) Identifies Object in Basket

-

Object not Visible From LC

-

HP Tech Concerned about Contamination Smears

-

HP Tech and Worker Exit LC

  • HPGF Oversight from 42'

See Diagram No. 1

UPPER CAVITY

-

HP Tech Advises Workers to Remain in Place

No Verification of Communication

-

HP Tech Exits UC to Count Smears

-

Worker Uses Light to Identify Object

-

Using Light Dislodges Object See Diagram No. 2

LOWER CAVITY RE-ENTRY

-

Worker Re-enters LC to Confirm Check-out

-

While Waiting for Check-out

  • Visually Inspects Object

-

Identifies as Crane Debris

-

LC Natural Collection Point

  • Picks up Object
  • Identifies as not Crane Debris
  • Drops Object

-

Co-worker and Crane Operator Intervene

-

HPGF Returns to Line of Sight Orders Worker to UC See Diagram No. 3

EVALUATION & RESTART

-

HPGF

  • Stops Work and Evaluates Situation

Object Handling not Identified

  • Counsels HP Tech

-

Leaves UC to get Respirator for HP Tech

-

HP Tech Agrees for Worker to Position Teletector

  • Varying Readings
  • Teletector Meter Observed by HP Tech

Maximum 40R/hr

-

HPGF/Worker

  • Return to UC See Diagram No. 4

.

EVALUATION AND RESTART

-

HPGF a Performs Survey a Concludes Work Area Within REP Limits

  • Re-evaluates Remaining Work
  • Limits Stay Time
  • Directs Worker to Avoid Object
  • Continues Evaluation of Object

-

Worker Re-enters LC

  • Completes Refueling Check-out and Other Work a

Exits LC

-

HPGF Verifies

  • Removal of Protective Clothing
  • No Anomalies

& Further Counsels HP Tech 0 Advises Contract HP Tech's Supervisor

FOLLOW-UP (SATURDAY-MONDAY)

Saturday

-

Object Evaluated to be Approximately 400 Rem/hr

-

Worker Notifies HP of Handling

-

Worker's Access Placed on Hold

-

Processed Dosimetry

-

Dose Evaluation Starts

-

Investigation Starts

-

HP Supervision Notified Monday

-

HP Management Notified

-

NRC Notified

CAUSES OF PROBLEMS IDENTIFIED

-

Self Reading Dosimeter Incorrectly Located Worker - Mis-judgement

  • HP Tech - Inattention to Detail

-

HP Tech and Worker Separated

  • Worker - Ineffective Communication

-

HP Tech - Ineffective Communication, Mis-judgement

-

Work Evolved to Exceed Scope Discussed in Tailboard

  • Worker - Mis-judgement

-

Object Handling Not Immediately Reported

  • HPGF - Ineffective Communications
  • Worker - Mis-judgement/Assumptions

EVENT ANALYSIS P. J. Knapp

EVENT ANALYSIS DOSE ANALYSIS CAUSES CORRECTIVE ACTIONS SUBSTANTIAL POTENTIAL RADIATION SAFETY PROGRAM SPECIFIC/NR QUESTIONS

DOSE ANALYSIS DOSIMETRY PLACEMENT OBJECT EVALUATION DOSE EVALUATION

Worker #1 TLD/PIC/PD-1 Results (mRem)

TLD PIC/PD-1 Dosimetry Location 2/19-2/20 2/19 2/20 Total Head 126

60 140 Chest 156 122

181 Right Ring 854

-

--

Left Ring 373

---

--

Right Leg 157 120

180 Left Leg 150 100

160

1

__

_1_1

OBJECT EVALUATION

-

TLD Measurement of Object

  • Dose Rate at 2mm Equals 330 mRem/sec or 1188 R/hr

-

GeLi and MCA Measurements of Object

Unit-i Unplanne d Extremity Exposure Calculated versus Measured Dose Rate from the Upender Object mremlsecond 100,000

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ll 10,00 I0 I 11 it I

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0.0_ 'l 1,000nc from Obec (inches)

DOSE EVALUATION INTERVIEWS TIME MOTION STUDY RESULTS

TIME MOTION STUDY

-

Video Taped Worker Picking up and Handling Object in Full PCs and Respirator

-

Consistently Demonstrated Object Held for 8 Seconds

DOSE EVALUATION RESULTS

-

(8 secs) (330 mRem/sec) = 2640 mRem Extremity

-

Total Extremity Dose 1/1/93 - 2/20/93 = 3300 mRem

-

Total Whole Body Dose = 157 mRem

CAUSES Inattention to Detail

-

Verification of Self Reading Dosimetry Placement Ineffective Communications

-

Separation From Coverage

-

HPGF Debrief Judgement

-

Self Reading Dosimetry Placement

-

Work Exceeded Scope Discussed in Tailboard

-

Dislodged Object

  • Handled Object

-

HP Tech Pursued Tangential Issue

-

Worker did not Immediately Report Object Handling

CORRECTIVE ACTIONS Inattention to Detail

-

Worker and HP Tech Counselled and Disciplined

-

Memo to HP Personnel to Re-emphasize Verification of Self Reading Dosimetry Placement

-

Expanded Self Reading Dosimetry Placement Details in REPs

CORRECTIVE ACTIONS Communications

-

Worker and HP Tech Counselled/Disciplined

-

New Procedure and Training for Planning Jobs and Controlling Exposure Provides Guidance for Verifying Communication

-

Communications Training Will be Added to

  • HP Annual Retraining
  • HP Contractor Entrance Training

CORRECTIVE ACTIONS Judgement

-

Worker

  • Worker Counselled/Disciplined

-

Other Personnel Involved

  • HP Tech Counselled/Disciplined
  • Foreman Counselled

-

Supervision: ROR Issued

CORRECTIVE ACTIONS Judgement (Continued)

-

Selected Groups - HP/Refueling/Steam Generators/Et * Reviewed Elements of This Incident With Significant Exposure Work Groups

-

Site Population

  • HP Memo to Radiation Workers
  • Discuss Incident in Annual Radiation Worker Retraining - Practical Factors
  • Revised PD-1 Video for New Personnel

TRAINING AND AWARENESS

-

Completed

  • Issued Memo to HP Personnel
  • Issued Memo to Site Population
  • Revised PD-1 Video for New Personnel
  • Revised Radiation Exposure Permits
  • Published HP News Articles
  • Updated Practical Factors

-

In Progress

SUBSTANTIAL POTENTIAL

-

Adequate Controls

  • Basket Survey
  • Worker's Training and Experience
  • Co-worker's Intervention
  • Crane Operator's Intervention
  • HP General Foreman Oversight

RADIATION SAFETY PROGRAM

-

Program Components Essential for Protection Were Present

-

Training of Workers

  • Mechanism for Defining Work Scope
  • Quality Radiation Exposure Permit Issued
  • Formal Tailboard
  • Qualified HP Personnel
  • Supervisory Observation

-

Program Characterized by Diligence and Attention to Detail Record of SALP 1 Performance

SPECIFIC CONCERNS WORK GROUP - HP COMMUNICATIONS CONTINUOUS HP COVERAGE PD-1 PLACEMENT

WORK GROUP - HP COMMUNICATIONS

-

Established Formal Process

  • MO/RWMS Interface

-

HP Division Planning Office

  • Interface With Work Group Planners and Supervision
  • Prepare Radiation Exposure Permit

-

Formal Tailboard

-

Weakness:

  • HP Tech Failure to Verify Communication Upon Leaving

-

Tailboard not Reconvened

CONTINUOUS HP COVERAGE

-

Generally Accepted Concept in Use

-

Defined for Site Population in Handbook

-

Value in More Extensive Guidance

-

Expanded Guidance

  • Practical Guidance Published as Procedure

PD-1 PLACEMENT

-

First Incident Occurred on Thursday

-

Second Incident Occurred on Friday

-

Insufficient Time to Notify

-

Incident Verses Trend

-

Revision of ROR Program

REGULATORY ASSESSMENT R. M. Rosenblum

REGULATORY ASSESSMENT SEVERITY LEVEL

-

Dose did not Exceed Limits

-

No Substantial Potential

-

No Breakdown in Program

REGULATORY ASSESSMENT MITIGATION FACTORS

-

Event Identified by SCE

  • Prompt Notification

-

Corrective Actions

  • Immediate/Short Term Actions
  • Additional Comprehensive Actions Completed and Underway

-

SCE has Consistent Record of Outstanding Past Performance

REGULATORY ASSESSMENT EXERCISE OF DISCRETION

-

Safety Significance is Low

  • Whole Body Exposure Below Planned and Expected Exposure
  • Extremity Exposure Well Below Regulatory Limits
  • Single Event

-

SCE's Overall Performance is Outstanding

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