Updated 02.08.2012: With information from the Environment Agency and EU
One of the more surprising permits needed by Cuadrilla and British Gas owner Centrica before beginning their two-year shale gas exploration project across Lancashire is one for the safe disposal of naturally occurring radioactive materials (NORM).
The permit is required because radium 226 was found last year in returned fracking fluids at the Preese Hall site.
Energydesk takes a closer look at the radioactive waste produced during shale gas extraction, and what can be learnt from full-scale production in the United States.
Does fracking involve radioactive materials?
In its Environmental Risk Assessment for Shale UK's environment agency lists exposure to NORM as a possible risk in shale gas exploration and requires shale gas drillers to obtain a permit for the extraction and handling of radioactive materials.
The process of fracking involves pumping water and chemicals very deep under ground to break apart rocks and release some of the gas they contain - sometimes this can contain naturally occurring radioactive material.
Radium 226 was the highest naturally occurring radioactive material (NORM) found in the flow back water from the Bowland shale measuring between 14 and 90 Becquerel per litre - according to an analysis by the Environment Agency (EA) in December 2011,
Even at its lowest levels, this exceeds the EA’s limit allowed for waste water disposal without a permit, which is any amount higher than 10 Bq/g.
A report by the AEA for the European Commission on the possible environmental risks of shale gas drilling in the EU noted that:
"The substances of potential concern comprise naturally occurring substances such as heavy metals, together with natural gas, naturally occurring radioactive material (NORM), and technologically enhanced NORM (TENORM) from drilling operations."
Why do you find NORM in fracking fluids?
As the name implies, NORM is found naturally underground in different quantities. However, when the rock is fractured during the drilling process these radioactive materials are released and resurface with the drill cuttings and waste water.
Is it dangerous?
Both the EA and AEA have identified NORM as a risk which needs to be managed.
Richard Shaw, radioactive waste team leader at the British Geological Survey said: “Certainly that [fracking] is the easiest way for radioactivity to get out from the rock.”
However, as NORM is classified as low-level radioactive waste, Shaw doesn’t expect that the radiation from fracking will be a problem. “Where’s the line between no impact and some impact for radioactivity? I don’t think people absolutely know, but low levels of radioactivity are around us all the time. My view would be that the impacts would be minimal.”
According to the US EPA: “Both internal and external exposure to gamma radiation is harmful. Gamma rays can penetrate the body, so gamma emitters like radium can result in exposures even when the source is a distance away.”
The problem is that we don't have any examples of the treatment of NORM from fracking in the UK at the moment because the industry is so young.
Are there problems in the United States?
The problem when handling radioactive materials is that things can go wrong.
US shale drillers have to deal with the same type of radioactive material as found in Lancashire - but their performance has been far from perfect.
In April a truck carrying drill cuttings from a fracking pad in the Marcellus Shale was rejected by a Pennsylvania landfill after setting off a radiation alarm. The truck was emitting gamma radiation from radium 226 at almost ten times the level allowed at the landfill.
While radium 226 occurs naturally in the Marcellus Shale (as well as the Bowland shale in the UK), Pennsylvania’s Department of Environmental Protection has launched a year-long study into radiation contamination associated with fracking wells. It will also be looking into the radioactivity levels in pipes and well casings, storage tanks, treatment systems, and trucks.
The report, co-authored by Marvin Resnikoff, a physicist at the University of Michigan and senior associate at Radioactive Waste Management Associates, states that “drilling contamination is entering the environment in areas directly connected to the drilling site through spills, too.
In the past three years, at least 16 wells whose records showed high levels of radioactivity in their wastewater also reported spills, leaks or failures of pits where hydro-fracking fluid or waste is stored, according to State records.”
The report also found that in many instances truck transportation of radioactive waste in Ohio violates federal standards, which includes truck tank design, minimum insurance requirements and proper signage indicating the load is radioactive.
What is the main risk?
In the UK, as in the US, fracking fluids are likely to be transported from site by truck, but it is not clear how this is regulated.
Tony Grayling, head of Climate Change and Communities at the EA said: “Traffic movements are a matter for the local planning authority.”
According to the 2011 Exemption Guidance, “All premises that store radioactive material or radioactive waste ‘in transit’ are exempt from the requirement to have a permit for that material or waste.”
It continues, stating: “There are no restrictions on the number of packages, the radionuclide concentration or the total activity.”
The only regulations that are in place for the company to follow include transport regulations concerning the storage of the radioactive material, including the packaging and security of transport storage facilities.
“As long as the cuttings and the water are treated appropriately and the resulting filters or sludges are disposed of appropriately in the appropriate facility then I think there should be no issues at all,” Shaw said.
How many trucks would be carrying waste fluid?
In a report by the Institute of Directors, it is estimated that a total of 666 truck movements are needed per well to transport the drill cuttings, drilling waste water, fracking fluid, and flowback water.
According to the report, 30 per cent flowback water is expected per well in the UK, or 40,800 cubic metres for a single pad with 10 wells. This would require 136 truck journeys per well, most of which would occur during the initial flowback period at the beginning of the well’s lifetime.
Where does the radioactive waste go once it leaves the frack-pad?
According to the waste management company Remsol’s website, “Past policy on the disposal of Very Low Level Waste and Low Level Waste (VLLW and LLW) respectively has been for it to be stored at the site where it is produced before being consigned to the UK’s only dedicated disposal facility: the Low Level Waste Repository (LLWR) near the village of Drigg in Cumbria.”
Once the waste is brought to LLWR it is stored in metal ISO containers which are then placed into “specially engineered landfill cells and covered with concrete for long-term storage whilst any radioactive contamination decays.”
However, it is expected that LLWR’s storage capacity will run out within the next 10 years, which is most likely before shale gas extraction enters its peak production phase.
In anticipation of the need for more disposal sites, some conventional landfills are applying to the EA to become newly licenced sites for VLLW and LLW. In August 2012 Sita in Lancashire was issued a radioactive substances activity environmental permit.
Do we have any other options other than landfills?
Remsol is currently working with “a client with operations in the burgeoning shale gas sector” to find “long-term, operationally sustainable option for removing naturally occurring radioactive material (NORM) from a wastewater it produces.”
According to their website, Remsol has developed a method to remove the NORM from the wastewater using a combination of physical and chemical separation techniques. After laboratory and plant-scale trials it found that the method was 90 per cent effective, “enabling it to be safely returned to the natural environment to once again become part of the water cycle.”
Will drilling produce radioactive waste in Balcombe?
Cuadrilla’s current plans to explore for shale gas in Balcombe were delayed last month when Friends of the Earth urged the Environment Agency to require the project to obtain a radioactive substances permit as well as a mining waste permit and a groundwater permit.
Grayling said of the exploratory phase: “It is likely that the waste fluid returning to the surface from this procedure will contain low levels of naturally occurring radioactive materials, sufficient to require a permit for their safe management and disposal.”
So while the drilling phase does not require a radioactive substances permit according to Grayling, the exploratory phase does because it produces waste due to the ‘acid wash’ (dilute hydrochloric acid used to clear limestone debris around the base of the borehole).
However, any permits obtained during the exploratory phase would need to be re-consulted based on the results found during exploration.