Interview by Rikki Stancich
One of the oil and gas sector’s more dangerous oversights is that naturally occurring radioactive material (NORM) waste can be treated as a 'low level' radioactive waste stream. A growing body of evidence indicates that health and environmental impacts of NORM have been well underestimated, and that NORM waste streams are increasing at an unmanageable rate.
Every year, the US oil and gas industry produces roughly 260,000 tonnes of NORM contaminated sludge and scale, and around 18 billion barrels of waste fluid. To provide context, a low, background level of radiation for the US is around 0.2 pCi/g. Produced water from oil and gas drilling contains around 9000pCi/g, while tank and pipe scale contains around 100,000pCi/g.
NORM contaminated materials contain uranium, thorium, lead and radon, and their respective decay elements (or so-called ‘progenys'). These materials present a risk to workers due to direct gamma radiation exposure and airborne radioactive dust inhalation via “Discrete” and “Diffuse” radioactive waste streams.
Created during the production process, technically enhanced NORM (TeNORM) is carried in the fluids from oil and gas reservoirs up to the earth’s surface. Barium, calcium and strontium sulfates carry atoms such as Radium 226 and Radium 228 through the produced fluids. As the fluids approach the surface, changes in temperature and pressure cause the barium and radium sulfates to precipitate out of solution and form scale on the inside, and sometimes the outside, of the tubulars.
The level of radioactivity can vary significantly, depending on the reservoir rock and the salinity of brine from the well. But in general, the higher the salinity, the more NORM/TeNORM is likely to be mobilised; and because salinity often increases with the age of a well, older wells tend to exhibit higher NORM levels.
Traditionally, final disposal methods for NORM waste have included spreading it on fields; leaving it in evaporation ponds (to leave a deadly legacy of contaminated soil and air born radioactive particles); or discharging it into the nearshore marine environment (a method still widely practiced). More recently, companies began pumping the waste back down hole and sealing it in abandoned wells, or injecting it into salt caverns.
Risks associated with NORM contamination were recognised in the mid-1980’s and since then, there has been some effort to raise awareness. However, international and US federal regulations governing NORM treatment and disposal have yet to be introduced. As a result, innovation in treatment processes has all but stagnated.
Until now, that is. DecomWorld speaks to The N.O.R.M Inc.’s CEO, Scott Hahn, about a novel approach to NORM decontamination that addresses and is helping to resolve issues and hazards presented by this burgeoning waste stream.
DecomWorld: What is the major challenge faced by oil and gas operators and contractors when carrying out NORM decontamination of end of life platforms and infrastructure?
Scott Hahn: The challenge is having key services available to industry to allow its NORM environmental and safety programs to evolve. The current standard practice is to water blast, but this generates a considerable waste stream in itself, which is costly to store, and for which, in many regions, no appropriate final disposal option exists.
Water blasting NORM contaminated equipment came to the industry 15-20 years ago and since then, the industry has become stagnant; the industry has been successful in advancing the efficiency of water blasting techniques, however such techniques result in the creation of high volume waste streams while using increasingly scarce water resources. New technology has not become widely available, until now.
DecomWorld: How does The N.O.R.M. Inc.’s decontamination solution address this, and why is it better suited to offshore oil and gas decommissioning than existing NORM decontamination methods?
Scott Hahn: We use dry blasting, which resolves the issue of storing cubic metres of waste stream; instead, you only need to store litres of waste.
The best way to decontaminate equipment is to do so at the actual site where the contamination arrives at surface. In this way, you minimise the potential for accidents or spills during transport, which presents a risk both to personnel handling the equipment and the environment.
We use “mobile” decontamination equipment at the client’s site, which can be set up within two hours. Because we use sand as a blasting medium, within a closed loop system, we are able to reduce the volumes of NORM contaminated waste by 95% through our technologically enhanced HEPA filtering system.
When people think of sand blasting, they think of sand flying all over the place, but our system is completely contained; the medium is recycled across several jobs until it disintegrates and becomes part of the waste stream itself.
The end product is 95% less volume: “litres” of NORM waste are produced, as opposed to several cubic metres of NORM contaminated waste.
DecomWorld: Final waste disposal presents a challenge in many regions. What are the current solutions and what does The N.O.R.M. Inc. propose?
Scott Hahn: Operators own the produced waste until final disposal. In other words, the client pays yearly to have waste stored at a static facility safely, often for years. Right now, decommissioning contractors in most regions are storing NORM waste, and are waiting until a final disposal point becomes available.
Waste streams are growing because of due diligence, but in regions like the Middle East, adequate facilities don’t exist with effective treatment or final waste disposal. Where final waste facilities are not available, The N.O.R.M. Inc. is working with governments, regulators and oil and gas producers to design a final waste disposal solution that will be piloted in the Middle East in the coming years. Once proven, the resulting studies will produce a final waste disposal solution that has opportunity to be offered globally.
DecomWorld: In the US and most other parts of the world, no official standard has been set for NORM regulation. To what extent do companies ensure employees are adequately protected from exposure to alpha, beta and gamma emitters present in NORM-contaminated waste?
Scott Hahn: There are no worldwide regulations, which means it is up to individual states and countries to set the standard. Generally the standard is aligned with the International Atomic Energy Agency’s standard for users of manmade radioactive sources.
With manmade sources of radiation the radioactive output factor is known because the source of radiation within the special form capsules have specific output factors that can be “calculated”. NORM radioactive waste may contain many different radioisotopes and although we do know the disintegration chain of events there still are too many radioisotopes within NORM waste to be accurate.
Half lives are calculated based on actually “knowing” when the stable atoms became unstable. With NORM waste it is nearly impossible to know when exactly the involved unstable radioisotopes began disintegrating (emitting radiation). Through stringent lab analysis this can be accomplished but in the oil and gas industry, as with many other industries, time is money and the longer NORM waste is present at surface the greater the danger to workers and the environment.
So when you accept the standards for NORM, you accept what was adopted from the manmade nuclear industry – the standards are the same across the board. These standards were set 30-40 years ago. They have been changed and updated a few times, but for us to really understand how radiation affects workers you need to study at least five generations of human beings to determine the effects of NORM radiation exposure.
Nagasaki and Hiroshima happened only 70 years ago. This represents only two complete generations, the third working in industry now and the fourth presently being born. At least another 70 years will pass before the scientific community can step up and firmly say “we now know the effects of NORM exposure”. This is not going to happen in my lifetime, but my grandchildren may get to read those headlines.
The oil and gas industry is now becoming much more diligent and deserve most of the credit for recent efforts to enhance and strengthen safety and environmental protocols. Too often the “blame” finger is pointed in their direction when really it is the industry that is creating awareness of NORM issues within industrial producing sectors.
But while operators have largely addressed the issue, it is generally third-party contractors, (which account for roughly 50% of the industry), that transport NORM contaminated articles over land and sea for decontamination treatment. As such, the onus is on these third-party contractors to take the necessary measures to protect their employees and the environment.
DecomWorld: What is considered the ‘safe’ limit for NORM exposure?
Scott Hahn: For nuclear energy workers of manmade radioactive sources the allowable radiation “whole body” dose is 50 millisieverts a year (50 mSv/yr). For non-nuclear energy workers, referred to as incidental workers (such as the third-party contractors), and members of the public, the maximum dose is 1 millisievert per year (1 mSv/yr).
Generally, this would represent 2 -5 chest x-rays at a licensed medical facility, depending on the individual and strength of the x-ray taken. Please understand that these are “gamma” exposures and that the source of radiation is “known” and therefore can be calculated.
With NORM radiation exposure there is still no sure way to determine the extent of exposure to alpha and beta particulate radiation. We do know the atomic weights and size of these unstable particles so protection can be assured. Continuing education through proactive training and safety programs is the best way to alleviate this issue.
These levels of exposure are based on the gamma-emitting radioactive source. With NORM, you are dealing with all three types of radioactive emitters, alpha, beta and gamma; the most dangerous of which is alpha. It poses the highest risk to human beings, as it carries a positive charge of +2 and poses higher risks due to the fact that an alpha particle may be actually ionising within the body and stabilizing becoming an element of stable helium.
Alpha particulates posses the exact atomic weight of Helium but do not have the negative charges allowing the Alpha particle to be stable element of Helium. Alpha radiation therefore acts in the exact same way as helium, being light and able to float in the surrounding atmosphere. Working within a “rich Alpha atmosphere”, (confined spaces specifically), presents many dangers. Knowledge and protection measures are key strategies to lower or even eliminate these risks.
DecomWorld: What standard protection equipment for handling NORM contaminated material should be issued to workers?
Scott Hahn: There are different protective measures for different types of radiation emanation. It is important for workers to know in advance what type of radiation contamination is in the equipment and what protective measures to take. If the type of radiation is unknown, an “educated guess” is not prudent practice.
Therefore the worker should be fully outfitted in proper protective equipment (NORM PPE). The eyes, nose, ears and mouth are mucus membranes and are considered possible entries into the internal structures of the human body. Protection of these areas must be mandatory at all times when working within a NORM contaminated environment.
Inhalation and ingestion should be avoided by wearing a correctly fitted protective mask, or a pressurised breathing apparatus (SABA or SCBA).
You should also protect the biggest organ on the body, which is the skin, as much as possible. Keep in mind that this organ is the most resilient organ on the human body but most workers in the oil and gas sector are likely to have cuts and abrasions and these are also considered a point of entry for particulate radiation.
In the Middle East, where we are dealing with unstable radon, radium, polonium and lead, not only are the heavy metals and salts soluble in water, there is a high rate of benzene, a carcinogenic gas that is absorbed through the skin and easily saturates water. It is the responsibility of contractors and oil and gas operators to protect workers from radiation and benzene exposure.
Between the two, radiation is considered a “long term exposure hazard”. Benzyne gas is definitely the more dangerous of the two as its effects can be almost immediate. This is another issue that must be dealt separately, but in most cases where a large volume of produced water is evident, benzyne can become dangerous at even low levels.
My point is, radiation protection must be integrated into existing safety programs and cannot take away or overtake other safety issues present at any industrial site. This can be an arduous task but with the professionals that are available in industry today can be adequately accomplished. The N.O.R.M. Inc. has these people and they are involved in our safety and environmental programs every step of the way.
NORM/TeNORM is an ever-growing danger that industry is aware of but more education and the evolution of present safety programs must take place. It is at a point now that can no longer be ignored by industry and regulators. For future generations’ sake we must act prudently now to alleviate the dangers in the future to both our children and the environment.
This is a “niche” market at the moment and I expect that there will be more services available in the future. Industry would welcome the new players and the modern advanced technology they offer. Education and action will be the key driving forces. It is one industry that offers the involved professional opportunity to learn something new every day...a key element of evolution and understanding.
To respond to this article, please write to the Editor: Rikki Stancich