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Necsa presentation to Portfolio Committee on Minerals and Energy

This presentation discusses the HSE management processes at Necsa's Calibration Facility and their performance in terms of radiation exposure. It includes an overview of the sequence of events surrounding a recent incident, corrective actions taken, and an overview of Necsa's HSE management processes.

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Necsa presentation to Portfolio Committee on Minerals and Energy

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

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

  3. Necsa calibration facilityfor radiometric instruments

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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)

  9. 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

  10. 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

  11. 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

  12. 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

  13. Overview of Necsa’s HSE management processes

  14. ACTS STANDARDS (SANS) IAEA/ICRP PERMITS/ LICENCE NECSA POLICIES AND HSE MANAGEMENT PRINCIPLES LEGISLATION AND SOUND MANAGEMENT PRINCIPLES HSE SYSTEM 150 DOCUMENTS 10 CHAPTERS

  15. 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 HAZARDOUS CHEMICAL SUBSTANCE CONTROL PROGRAMME FIRE PREVENTION AND PROTECTION AND EMERGENCY PLANNING ENVIRONMENTAL MANAGEMENT COMPLIANCE ASSURANCE PROCESS SAFETY ORGANIZATION

  16. 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

  17. Necsa’s performance regarding worker radiation exposure

  18. 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)

  19. 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

  20. 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 < 1mSv/a

  21. Requests for medical information

  22. 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)

  23. 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%)

  24. INITIAL REQUEST FOR INFORMATION

  25. LATEST REQUEST FOR INFORMATION

  26. 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

  27. 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

  28. 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).

  29. 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).

  30. 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”

  31. Thank you very much!

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