Costs of dealing with waste water from fracking could be significant and make shale exploitation uneconomic in the UK, according to leading academics.
A report published by the Natural Environmental Research Council this week said there was “huge uncertainty” about how much waste water would be produced by UK fracking and how it would be cleaned or reused.
It concluded there was unlikely to be enough industrial waste treatment capacity for an operational shale gas industry and there was “a pressing need” for research and development of new technology.
It also identified information gaps on the impact of fracking on human health, emissions, earthquakes, public opinion and water quality
The report is the outcome of a workshop held in November last year involving nearly 50 UK and US academics and regulators. From the UK, they included researchers at 12 universities, as well as representatives from the Environment Agency, Department of Energy and Climate Change, the industry body Uk Onshore Oil and Gas and the British Geological Survey.
The workshop participants identified more than 140 priority questions where research was needed on the potential environmental impacts of unconventional hydrocarbons. Of these, about half needed to be addressed in the next year, they said.
“Huge uncertainty” on waste
One of the biggest knowledge gaps involved disposal of waste and produced water from fracked wells.
The authors said:
“A huge uncertainty, given the immaturity of unconventional oil and gas development in the UK, is how much waste water will be produced and regulatory and technical mechanisms for cleaning it or directly reusing it.”
In the US, most waste and produced water is injected deep into oil and gas wells. This is cheaper than treatment but has been linked to earthquakes, or induced seismicity, and removes water from the water cycle.
In the UK, deep water injection is currently not an option to the shale industry, the report said.
“Without deep well disposal, it is likely that treatment of the dissolved solids will be required and so research into cost-effective means of doing this is important to the implementation of unconventional oil and gas production in the UK.”
The report concluded:
“The costs related to waste water production may be significant and could make shale exploitation uneconomic. Research into potential uses of the flowback and produced water that might require less treatment should be pursued as well as treatment schemes taking advantage of cheap power.”
Without deep well disposal, the report said:
“There is unlikely to be sufficient industrial wastewater treatment capacity to service the needs of a mature operational industry and so there is a pressing need to address this through research and technology development.”
It said research was currently underway into how and when waste water could be disposed of in wells in the UK and how it could be reused as a hydraulic fracturing fluid.
The issue of waste water disposal was a key issue at the public inquiry into Cuadrilla’s plans to frack at two sites in the Fylde area of Lancashire. Friends of the Earth’s witness, Alan Watson, gave evidence that waste water from the proposed wells would conservatively use 68% of the total available capacity of two of the three national treatment facilities. He also gave evidence that the concentration of chemicals in the waste water may be at levels greater than those allowed in the permits of the treatment facilities.
Emissions: reliable data needed
The report said reliable data was needed on total greenhouse gas emissions from the “cradle to the grave” for shale gas and oil. These should be compared with other energy sources to inform climate change policy and understand the impact on legally-binding emissions targets.
The report recommended:
“More monitoring of unconventional oil and gas infrastructure is needed to understand which parts of the system are the biggest emitters and when these emissions occur. There is a gap in knowledge around what equipment the emissions are from, for example are they from tanks, gathering lines or wastewater treatment facilities?”
“Emissions from the entire supply chain need to be measured so the full impact is understood”.
The report also acknowledged US shale operations were associated with the release of volatile organic compounds (VOCs), most of which are toxic and contribute to air quality problems. There is “substantial uncertainty” about these releases, it said, and called for answers to the questions:
“What are best management practices for the control of emissions of volatile organic compounds and how do they change as a function of type of operation and procedures in place during the operation.”
Earthquakes: questions over UK traffic light system
The report also called for more research on how fracking leads to earthquakes and how to measure seismic activity.
“Of major concern is the ability to predict the maximum potential earthquake as a result of hydraulic fracturing. This may be related to the locations of faults, and research into how to detect and avoid faults is an important goal.”
It also questioned the value of the UK regulation known as the “traffic light system”, which requires fracking operations to stop if seismic activity reaches a level of 0.5. The report suggested there were problems with measuring this limit:
“At the current time, the regulatory threshold for action in the UK may not be able to be measured and therefore the defined threshold is of little benefit.”
Public opinion: “how do we change perceptions?”
The report recommended research on what it called “the most effective approaches for better engaging communities”.
The purpose, it said, was to “provide the public with the information they need to understand and evaluate the potential environmental impacts of hydraulic fracturing.”
But there was evidence elsewhere in the report that workshop participants were looking to change public opinion in support of shale gas. Among the questions they said they wanted to answer were:
“In the long run, how do we change people’s perceptions towards this industry? To advertise more and educating them? Or maybe our knowledge is yet limited and that’s why we cannot convince them”.
The report also identified other areas for research including:
Surface spills “Transportation and treatment of these waters can increase the opportunities for such spills”
Public health “Very early stage. Lack of understanding of long term impacts yet a potentially significant public concern.”
Water quality identifying leaks; sub-surface migration pathways; flowback water chemistry; risk assessments to improve leak detection; risks to human health from contamination of shallow groundwater and drinking water.
Joint US-UK Workshop on Improving the Understanding of the Potential Environmental Impacts associated with Unconventional Hydrocarbons. Final report by Danny Reible, Texas Tech University, and Richard Davies, Newcastle University, published 3 May 2016. Link (36.7MB)