Necsa presentation to Portfolio Committee on Minerals and Energy

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Necsa presentation to Portfolio Committee on
Minerals and Energy

• 25 May 2005
• Presented by
• Dr. van Zyl de Villiers

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Contents

• Instrument calibration facility
• HSE management processes
• Performance w.r.t. radiation exposure
• Requests for medical information

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Necsa calibration facilityfor radiometric
instruments
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Sequence of events

• Earthlife Africa (ELA) inspected site on 23 April
  2005 without knowledge to Necsa
• 26 April 0900 Necsa informed by NNR of ELAs
  intention to hold press release at a secret
  nuclear waste dump
• ELA, press and NNR representative arrived at site
  at about 1200
• 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

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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

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Sequence of events (cont.)

• DME requested summary report evening of 27 April
  and extended report by 800 on 28 April
• Meeting between DME, Necsa and NNR held at DME
  offices at 1100 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

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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

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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)

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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

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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

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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

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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

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• Overview of Necsas HSE management processes

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ACTS STANDARDS (SANS) IAEA/ICRP PERMITS/
LICENCE NECSA POLICIES AND HSE MANAGEMENT
PRINCIPLES
LEGISLATION AND SOUND MANAGEMENT PRINCIPLES
HSE SYSTEM
150 DOCUMENTS 10 CHAPTERS
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HSE SYSTEM
150 SYSTEM DOCUMENTS
HSE CHANGE MANAGEMENT PROCESS INCL PROJECT
APPROVAL
PREMISES AND HOUSEKEEPING
BEHAVIOURAL BASED SAFETY (BBS) PROCESS
MECHANICAL, ELECTRICAL AND PERSONAL PROTECTION/
SAFEGUARING
RADIATION PROTECTION PROGRAMME
10 CHAPTERS
FIRE PREVENTION AND PROTECTION AND EMERGENCY
PLANNING
HAZARDOUS CHEMICAL SUBSTANCE CONTROL PROGRAMME
COMPLIANCE ASSURANCE PROCESS
ENVIRONMENTAL MANAGEMENT
SAFETY ORGANIZATION
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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

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• Necsas performance regarding worker radiation
  exposure

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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)

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Public dose limit and constraints(µSv/a
microsieverts per annum)
50 µSv/a ALARA margin
2400 µSv/a (Average dose from background)
50 µSv/a Air pathway
Average actual Necsa public dose (0.8 of nat.
background)
International recommended public dose limit
150 µSv/a Water pathway
Necsa public dose limit
1000 µSv/a
250 µSv/a
20 µSv/a
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Worker dose limits (mSv/a millisieverts per
annum)
International recommended worker dose limit
20 mSv/a (averaged over 5y Not more that 50
mSv/a)
Average Necsa radiation worker dose
lt 1mSv/a
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• Requests for medical information

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Requests for medical records

• 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)

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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)

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INITIAL REQUEST FOR INFORMATION
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LATEST REQUEST FOR INFORMATION
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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

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Challenges (cont.)

• Personal information is sometimes inadequate to
  uniquely identify the individuals.
• Legal requirements for retention periods of
  records differ, e.g.
• Workers compensation 3 years
• Medical history 40 years
• Incident reports 3 years
• Human resources 7 years

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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).

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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).

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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

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Thank you very much!