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Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

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Page 1: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Necsa presentation to Portfolio Committee on Minerals and Energy

25 May 2005

Presented by :

Dr. van Zyl de Villiers

Page 2: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Contents

Instrument calibration facility

HSE management processes

Performance w.r.t. radiation exposure

Requests for medical information

Page 3: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Necsa calibration facilityfor radiometric instruments

Page 4: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Sequence of events

• Earthlife Africa (ELA) inspected site on 23 April 2005 without knowledge to Necsa

• 26 April 09:00 Necsa informed by NNR of ELA’s intention to hold press release at a “secret nuclear waste dump”

• ELA, press and NNR representative arrived at site at about 12:00

• Appeared in news since that afternoon.• Earthlife claimed dose rate levels of between 20 –

30 µSv/h on site • Necsa provided NNR with preliminary statement

based on information then available

Page 5: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Sequence of events (cont.)

• During evening of 26 April NNR requested Necsa to verify measurements taken by ELA

• Measured levels ranging from natural background to a maximum of 27 µSv/h (Thorium slab 1)

• 27 April NNR visited site • Requested that site be secured; gate locked immediately

and full-time security guard placed on site• NNR issued letter to Necsa requesting some actions,

e.g. signposting, securing area, reporting as a nuclear occurrence and a detailed report - to be complied with by 29 April

Page 6: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Sequence of events (cont.)

• DME requested summary report evening of 27 April and extended report by 8:00 on 28 April

• Meeting between DME, Necsa and NNR held at DME offices at 11:00 on 28 April

• Decision to investigate existence of other similar sites and to talk to media

• Necsa Corporate Communication had numerous telephonic and TV interviews 28 & 29 April

Page 7: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Background on the calibration site

• Upsurge in uranium exploration during 1970s created need for standardization and calibration of radiometric field instruments

• Facility built 1972 and upgraded 1979• 11 flat-circular concrete slabs (2 meters in

diameter and 300mm thick) and 2 borehole type facilities containing known amounts of uranium, thorium and potassium

Page 8: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Background (cont.)

• Used for calibration of field spectrometers for quantitative in-situ determination of U, Th and K as well as for accurate calibration of well logging equipment

• Naturally occurring ores incorporated homogeneously and immobilized into concrete matrices

• Radioactive material not processed but in form as it occurs in nature (to simulate typical ore bodies)

Page 9: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Background (cont.)

• Facility extensively used by many organizations and companies, but diminished since late 1980s

• Situated on Necsa property• Borders minor gravel road about 600m from

main road• Site was chosen due to low natural background

levels and to allow easy access for external users

Page 10: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Status of Site

• Identified as zone with elevated radiation levels on Necsa site; included in list of current operating and shut-down nuclear facilities submitted to NNR

• Passively safe • Inadvertent exposure controlled by locked gate

and cattle fence; locked steel covers over slabs• Security inspection on 15 April 2005 found lock

and signposting in order

Page 11: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Radiological risk

• Prevailing dose rates between background levels and maximum contact dose rate of 27 µSv/h

• Levels above background only detectable 3 m from uranium and thorium pads with highest levels

• Maximum ambient dose rate 1 µSv/h in area, i.e. 250 hours to be spent in area before reaching public dose limit of 250 µSv/a

• Because of remoteness and infrequent use credible exposure scenarios will present much lower exposures to individuals, which will not result in any detrimental health effects

Page 12: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Corrective actions

• Immediate replacement of lock on gate• Replacement of proper signposting• Erection of proper security fence (full-time

security until completion of fence)• Inspection of site by Necsa security staff during

each shift • Establish need for further use of site within 6

months; rehabilitate if no need is identified

Page 13: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Overview of Necsa’s HSE management processes

Page 14: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

LEGISLATION AND SOUND MANAGEMENT

PRINCIPLES

HSE SYSTEM

ACTS

STANDARDS (SANS)

IAEA/ICRP

PERMITS/ LICENCE

NECSAPOLICIES AND

HSE MANAGEMENT PRINCIPLES

150 DOCUMENTS10 CHAPTERS

Page 15: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

HSE SYSTEM

150 SYSTEM DOCUMENTS

PREMISES AND HOUSEKEEPING

MECHANICAL, ELECTRICAL AND PERSONAL PROTECTION/ SAFEGUARING

FIRE PREVENTION AND PROTECTION AND EMERGENCY PLANNING

COMPLIANCE ASSURANCE PROCESS

RADIATION PROTECTION PROGRAMME

BEHAVIOURAL BASED SAFETY (BBS) PROCESS

HAZARDOUS CHEMICAL SUBSTANCE CONTROL PROGRAMME

ENVIRONMENTAL MANAGEMENT SAFETY

ORGANIZATION

10 CHAPTERS

HSE CHANGE MANAGEMENT PROCESS INCL PROJECT APPROVAL

Page 16: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

EXTERNAL AND INTERNAL INSPECTIONS AND AUDITS

HSED AUDITORS INTERNAL AUDITS

HSED ISO 9000: 2000 CERTIFIED

EXTERNAL AUDITS:

NOSA

NATIONAL NUCLEAR REGULATOR

SABS

CONSULTANTS

APPROVED INSPECTION AUTHORITIES

Page 17: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Necsa’s performance regarding worker

radiation exposure

Page 18: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Terminology

The strength of a radioactive source is called its activity, which is measured in becquerels (Bq).A becquerel is one disintegration per second.

The measure of the biological effect of radiation on a human is called dose and is measured in

sievert (Sv).(1 Sv = 1000 mSv = 1 000 000 μSv)

Page 19: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Public dose limit and constraints

(µSv/a = microsieverts per annum)

2400 µS

v/a (A

verage dose from background)

250 µSv/a

150 µSv/a Water

pathway

50 µSv/a Air

pathway

50 µSv/a ALARA margin

1000 µSv/a

Necsa public dose limit

International recommended

public dose limit

20 µSv/a

Average actual Necsa public dose

(0.8% of nat. background)

Page 20: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Worker dose limits (mSv/a = millisieverts per annum)

20 mSv/a (averaged

over 5yNot more

that 50 mSv/a)

International recommended worker dose limit

Average Necsa radiation worker dose

< 1mSv/a

Page 21: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Employee Radiation ExposurePerson with highest exposure vs Dose Limit

1995 - 2005

0

10

20

30

40

501

99

5

19

96

19

97

19

98

19

99

20

00

20

01

20

02

20

03

20

04

20

05

Year

mS

v

Dose Limit (mSv) Individual with Highest dose (mSv)

Page 22: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Employee Radiation ExposureThe Average Dose (mSv) vs Dose Limit

1995 - 2005

00.10.20.30.40.50.60.70.80.9

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

Year

mS

v

Avg Dose (mSv)

Page 23: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Employee Radiation ExposureThe Average Dose (mSv) vs Dose Limit

1995 - 2005

0

10

20

30

40

5019

95

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

Year

mS

v

Dose Limit (mSv) Avg Dose (mSv)

Page 24: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Requests for medical information

Page 25: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

No claims received i.t.o.:

• NNR Act (47 of 1999)

• COID Act (130 of 1993)

Only requests for information i.t.o.:

• Promotion of Access to Information Act (2 of 2000)

Requests for medical records

Page 26: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Requests for medical records (cont.)

- Number of requests received via Earthlife Africa: 173

- Number of files submitted to ELA: 22 (only medical files as per initial information requested)

-  Number of requestors that were registered as radiation workers: 63 (36%)

- Number of individuals that could to date not be identified as former Necsa employees: 33 (19%)

Page 27: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

INITIAL REQUEST FOR INFORMATION

Page 28: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

LATEST REQUEST FOR INFORMATION

Page 29: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Challenges

- Promotion of Access to Information Act (Act 2 of 2000) was promulgated in 2000. Records requested are for periods before 2000 (e.g. 1970 – 1984).

- Information is available but not readily retrievable because it is held in different systems at Necsa, e.g.

• Medical information• Dosimetry and biological monitoring results • Facilities surveillance data • Human resources information • Incident reports

Page 30: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Challenges (cont.)

– Personal information is sometimes inadequate to uniquely identify the individuals.

– Legal requirements for retention periods of records differ, e.g.• Worker’s compensation 3 years• Medical history 40 years • Incident reports 3 years• Human resources 7 years

Page 31: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Necsa actions

• The Necsa Board of Directors is setting up an independent task team to investigate allegations by ELA and former employees.

• A task team has been established to compile the medical records of current and previous employees (ca. 25 000) to combine all medical related information.

• Modification of the database of medical exposures to identify record items available and not available (for previous employees). Records not available for current staff will be established where possible (e.g. where a baseline medical was not performed) (June 2005).

Page 32: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Necsa actions (cont.)

• A system will be developed and implemented to identify individuals not fully participating in the health care programme (June 2005).

• Health Hazard Identification and Risk Assessments (HIRA) will be reviewed for all facilities (July 2006).

• Workplace and medical surveillance programmes (including dosimetry and biological monitoring) will be adapted, where necessary, in accordance with the HIRA (September 2006).

Page 33: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Case study: An investigation into the health of US nuclear workers

• Investigation of 53,000 US nuclear industry workers from 15 nuclear utilities between 1979 and 1997.

• Mortality rates of these workers 60% lower than comparable US mortality rates for general population similar in terms of age and gender.

• Ascribed to the “healthy worker effect”

Page 34: Necsa presentation to Portfolio Committee on Minerals and Energy 25 May 2005 Presented by : Dr. van Zyl de Villiers

Thank you very much!