Researchers at Edinburgh University have warned that cost of waste treatment and a shortage of specialist facilities could limit the development of fracking in the UK.
A team from the university’s School of Geosciences estimated that treating the salinity and other chemicals in fracking wastewater at existing facilities could cost between £100,000 and £1 million per well under current treatment regulations. This represented between 2% and 26% of the expected total revenue from each well, they said.
Operators could face additional costs of about £163,000 per well to dispose of concentrated sludge containing naturally occurring radioactive material, known as NORM.
The study, published in the journal Environmental Science Water Research & Technology, looked at wastewaters from wells in the US to better understand the volume and make-up of wastewater that would be generated by a UK shale gas industry. It also reviewed the methods used to treat waste from the fracking process.
Only one shale gas well in the UK has produced waste from high volume hydraulic fracturing so far. But the researchers said the fluid could be several times saltier than seawater and contain NORM.
They found that the capacity for treatment of NORM was currently limited in the UK and could restrict multiple fracking operations if not addressed. Under current regulations, NORM concentrated sludge must be disposed in permitted landfill sites, adding to costs of dealing with waste.
The lead researcher, Megan O’Donnell, said:
“Treating wastewater could require a large outlay of the expected revenue from each well, affecting industry profitability.
“The UK’s capacity to treat the radioactive material in wastewater is currently limited, which could pose serious waste management issues if the shale gas industry expands at a faster rate than the increase in treatment facilities.”
There are currently four treatment facilities in the UK that had permits to handle liquid waste containing NORM. The facilities are: FCC Knostrop in Leeds, Bran Sands in Middlesbrough, Castle Environmental in Stoke-on-Trent and FCC Ecclesfield in Sheffield.
The study said there was a limit of 826m3 on the volume of waste containing NORM that could be received each day by these plants.
“If the volume of FP [fracking waste] water produced during fracturing exceeds this the capacity of the available treatment facilities could become critically stressed.
“Without alternative storage options or emergency treatment capacity, operations would be forced to cease until the fluids can be appropriately handled.”
The study concluded that there was no co-ordinated strategy for the management of liquid fracking waste in the UK.
It also said options for disposal without treatment were limited. The viability of injecting fracking waste underground looked uncertain and there was no comprehensive assessment of suitable sites.
The study’s coordinator, Dr Stuart Gilfillan, said:
“We suggest that industry, wastewater treatment plant operators and UK regulatory bodies work together to produce a coherent strategy for managing wastewater.
“This would serve to assure the public of its safety and prepare for the expansion of treatment capacity required should a shale gas industry develop in the UK.”
Ken Cronin, chief executive of the industry body, UK Onshore Oil and Gas, said:
“At this early stage in the development of the industry there are an appropriate number of Environment Agency approved facilities in the UK for the treatment of our waste water.
“The industry has been working with the Environment Agency and a number of leading institutions and companies in the waste management sector to bring techniques to the UK that enable fluids to be recycled on site and NORM wastes to be managed appropriately. Through this strategic work on waste with regulators, the supply chain and professional institutions, we believe the UK can lead the way on reducing wastes and achieving wider environmental outcomes for the onshore oil and gas industry. It is surprising, therefore, that the researchers did not make contact with the industry, as if they had they would then have understood the extensive work, research and planning we are doing in this area.
“There are some poor assumptions made in the research around revenue per well. The 1.8 billion cubic feet (bcf) estimated ultimate recovery (EUR) assumption includes some of the poorer performing wells of the US, while analysis of the top 6 performing shale gas plays of the US reveals an average EUR of 5bcf, over double the authors estimate(1). The use of this data noticeably reduces the inflated percentage cost projections conducted in this study.
“In the UK, optimal geologies are and will be mapped and explored with state of the art techniques and methods. The same attention and innovation will be paid to the disposal of the waste from these sites.”
Lee Petts, managing director of the consultancy Remsol, said:
“The UK waste management sector has a proud history of responding to market demand, investing in innovation and capacity-building where needed. A good example concerns incinerator fly ash – prior to the practice being banned, this hazardous residue from municipal waste incineration was simply sent to landfill but is now typically used either for its alkalinity value as a reagent in the treatment of acidic wastes or is ‘washed’ to remove insoluble metals and other constituents in order to enable it to be recycled into concrete block manufacture. Waste industry treatment capacity for fly ash has grown in-step with the expansion of waste-to-energy incineration, which would have been hampered otherwise.”
- Wastewater from hydraulic fracturing in the UK: assessing the viability and cost of management. M C O’Donnell, S M V Gilfillan, K Edlmann and C I McDermott in Environmental Science Water Research & Technology Online link