Radiation Safety

1. Radiation Safety NORM Presented By: Etech Environmental & Safety Solutions, Inc.

2. Radioactivity • The tendency of unstable atoms to undergo radioactive decay. • Radioactive atoms are called radionuclides.

3. Background Radiation • Is unavoidable • Comes from cosmic sources and earth materials • Averages 10 - 20 uR/hr gamma in the USA

4. What is NORM? • “Naturally occurring radioactive material” • The oil & gas industry is mainly concerned with 3 types of radioactive materials: • Radium – 226 • Radium – 228 • Radon – 222

5. A Quick Chemistry Lesson! • Uranium 238 and Thorium 232 decay and change into many different radioactive materials (daughter minerals), including Radium 226 and Radium 228, finally becoming a stable Lead (non-radioactive).

6. NORM • Naturally Occurring Radioactive Material • Prevalent in scale from produced water operations in certain oil fields • Most common emitter is Alpha but can also contain Gamma & Beta • Greatest hazards present for most sites are respiratory and ingestion • Some sites may have time exposure potential

7. NORM • Radium will dissolve readily into production water associated with oil & gas production (water rich in chlorides) • It will not dissolve into the oil itself. • Example: When water flooding a formation. (inject water at various areas around a formation to aid in the flow rate to the well.) The mixing of formation water and injection water can cause scale to form.

8. NORM - Scale NORM accumulation in scale is typically the result of radium precipitating out of the produced water along with barium sulfates.

9. Major Types of Radiation

10. Definitions • Roentgen – The unit of measure for X or gamma radiation in air. (R) • Roentgen Absorbed Dose (RAD) – The unit of measure for radiation energy transferred to an absorbing tissue. • Quality Factor – The factor by which absorbed doses are multiplied to obtain a quantity that expresses the risk associated with the dose. • Roentgen Equivalent Man (REM) – The unit of measure which represents the risk associated with radiation exposure. • 1 R = 1 REM

11. Example Rad x QF = Rem Gamma 1 Rad x 1 = 1 Rem Beta 1 Rad x (1 to 2.6) = 1 to 2.6 Rem Alpha 1 Rad x 20 = 20 REM

12. Sub-units • Millirems (mRem) • 1000 mRem = 1 Rem • Microrems (µRem) • 1000 µ Rem = 1mRem • 1,000,000 µRem = 1 Rem

13. 700 Rem = LD100 600 Rem = LD99 450 Rem = LD50 200 Rem = LDLO 100 Rem = TDLO 25 Rem = EDLO Acute Exposure Risk A normal U.S. citizen has a 25% risk of cancer. 1 Rem increases that risk to 25.03%. 100 Rem increases the risk to 28%. The USEPA action level for personnel safety is 1mr above background

14. Why be cautious of NORM? • Radium is a “bone seeker” • If radium is ingested or inhaled, it will migrate to the bones of the body where it has the ability to remain for a very long time. • Radium is carcinogenic and is directly linked to diseases of the bones such as leukemia and bone cancer.

15. Should I be worried? • The National Council on Radiation Protection and Measurements (NCRP) has stated that while exposure of workers and the general public should be kept to the lowest practical level at all times, the presently permitted doses represent a level of risk that is small compared to other risks encountered in everyday life.

16. Exposure Reduction Mechanisms • Time • Amount of time exposed to and away from the source • Distance • Closer is not always better • Shielding • Dependent upon the type of radiation • Can include respiratory and skin protection • ALARA • As Low As Reasonably Achievable

17. Dose Limits • Total Effective Dose Equivalent of 5 Rem per calendar year to the whole body for workers exposed to occupational radiation. • For individual members of the public the dose is limited to 0.1 Rem per year • A declared pregnant women is limited to a Dose Equivalent to the Embro/Fetus of 500 mRem during her pregnancy, delivered at a recommended rate of approximately 50 mRem per month or less.

18. Health Risks

19. NORM • Naturally occurring radioactive materials are present all around us. • They are found in our backyard soil, food drinking water, even in our bodies.

20. TENORM • TENORM is “technologically enhanced” • Oil & gas production and refining are examples of technical processes which concentrate NORM.

21. Where NORM is found in the Oilfield • Water lines • Flowlines • Separators • Water/Production Tanks • Pumps • Heater treaters • wellheads

22. General Regulatory Information • Department of State Health Services (DSHS) regulates the management (receipt, possession and storage), *transportation and *disposal of NORM. • Texas Railroad Commission (TRRC) regulates the requirement for surveying tank batteries and the disposal of oil and gas NORM waste.

23. General Regulatory Requirements cont. • All tank batteries must be surveyed by the operator and labeled if NORM is present…… (TRRC). • Any equipment with a reading of 50uR/hr or greater (including background) is considered NORM contaminated (TRC,DSHS). • Soils/BS&W with a reading of 30 pCi/g of Ra 226, Ra 228, Thorium or Total activity > 120 pCi/g is considered NORM contaminated (DSHS).

24. General Regulatory Requirements cont. • All operators engaged in the possession, use, transportation or storage of NORM are a general licensee. • All contractors engaged in the removal, packaging, transportation and/or disposal of NORM are required to have a specific license.

25. Contractor Requirements • For each project/job a contractor must address the following: • Preliminary Assessment (NORM, Physical & Chemical) • Public Protection • Personnel Protection • Visitors • Air Monitoring • Contamination Minimization • Decontamination

26. Instrumentation • Determine risk of exposure • Determine types of radiation

27. Instruments • Consist of two main components • Meter • Probe (reads gamma)

28. Meters • Two types • Analog • Digital • Most common • Model 3 (Analog) • Model 2241 (Digital

29. Analog Meters • Can be simple or complex • Can be set to read in specific or multiple units • May require scale adjustment and use of basic math to determine the correct reading

30. Analog Meters - Scaling • Reading is taken based upon the reading of the meter multiplied by the setting of the scale (Red Arrow) • May require resetting (Yellow Arrow) every time the scale setting is changed or the instrument overloads the current scale

31. Digital Meters • Most configured to self scale, reduces the potential for error. • Depending upon the instrument configuration, will read in either uR/hr, mR/hr or CPM. • Can automatically adjust for the type of probe used.

32. Probes • Two primary types of probes used: • Gamma Scintillation • Reads is uR or mR per hour • Alpha/Beta • Common Name: Pancake Probe • Measures in CPM

33. Other Probes

34. Probe Care and Use • Take care to prevent the probe from falling or hitting any hard surface • The membrane on a “Pancake” probe can be punctured with minimal effort • All probe surfaces should be kept clean of oil, grease, dirt or significant amounts of dust • Never immerse a probe in water or any other cleaning solution

35. General Instrument Care and Use • Always perform a battery check before and after use. • Always check the probe against a known source before and after use. • Always reset the instrument when changing scales, probes or if an overload occurs. • Always keep the instrument in a secure location when transporting and remove batteries.

36. Limitations of Instruments • Accuracy may vary between user • Distance from source • Speed of monitoring • Thickness and type of material surrounding the source • Annual calibration

37. NORM meters are NOT Intrinsically Safe

38. Never use a NORM meter in an area where explosive vapors may be present. The meter could set off an explosion.

39. Always check for flammable vapors and H2S with an appropriate instrument before taking a NORM reading – Especially in a confined space such as a tank or a heater treater

40. Questions ?