SCIENTISTS investigating the possibility of spills or leaks from fracking well sites or tankers have said strict controls would be a necessity to minimise the risk.

The research, by the Researching Fracking in Europe (ReFINE) consortium, jointly led by Durham and Newcastle universities, looked at the potential for spills from any future UK shale gas site and also the tankers used to transport chemicals and contaminated fluids to and from the sites.

They examined data related to the transportation of milk and fuel in the UK and from the oil and gas industry in parts of the USA, looking at incidents such as road traffic accidents and spills involving tankers in the UK’s fuel and milk industries as a comparison for any future journeys involving vehicles transporting to and from fracking sites.

Hydraulic fracturing involves injecting water, sand and chemicals at high pressure into rock which then cracks to release the shale gas.

Chemicals are usually stored on site before being mixed with the water and sand and the mixture that has been pumped into the ground is often taken away by tankers for treatment after use.

Spills of fracking fluid, produced water, flowback water and chemicals are potentially hazardous if they enter natural ecosystems.

A shale gas well site containing 10 wells could expect to be visited by an estimated 2,856 tankers, each with a potential capacity of 30,000 litres, over the first two years of drilling, the researchers said.

Data relating to milk tankers showed this volume of traffic could potentially equate to one incident for every 12 shale gas well sites and one spill for every 19 well sites over the lifetime of a well, up to a period of 20 years.

Milk transportation was included in the study because it is comparable with a potential shale gas industry, as many well sites could be situated in rural areas with tankers using similar roads.

ReFINE said the dairy industry was a good comparator as, similarly to potential fracking related spillages, milk tanker spillage can be highly polluting to natural ecosystems. For example, in July, 2002 a tanker crashed into a bridge and 19,000 litres of milk was spilt into a stream in Staffordshire, UK. It was reported that 50,000 fish were endangered.

Data relating to fuel industry tankers suggested there could potentially be one incident for every 29 shale gas sites developed and one spill for every 55 sites over the lifetime of a well site.

Information about milk/fuel tanker incidents between 1998 and 2016 was collected using online media reports and therefore could be understated if not all incidents were reported in the press, the researchers said.

Based on data from Texas, USA, the researchers also found that one onsite spill could potentially occur for every 16 UK well sites, each containing 10 wells.

Lead author Sarah Clancy, a PhD student in the Department of Earth Sciences at Durham University, said: “Given the highlighted risks of spills from shale gas operations, mitigation methods are a necessity.

“If a shale industry is to go forward in the UK, or across Europe, appropriate strategies need to be in place to minimise the risk of spills associated with well site activities and the transportation, handling, storage and disposal of hydraulic fracturing related fluids.”

“For example, to mitigate against spills on the road the researchers highlight the importance of regular vehicle inspections and maintenance; specialised training and instruction for drivers; and appropriate driving schedules and routes.”

Professor Richard Davies, Newcastle University, who leads the ReFINE project, said: “Our research on shale gas continues to follow up on the questions members of the public have raised about fracking. Our new research informs government, industry and the public on how likely spillage would be.

“This is timely as fracking is now recommencing onshore in the UK after it was halted because of fracking-induced earthquakes in 2011.”

Ken Cronin, Chief Executive of UK Onshore Oil and Gas, said: “The report shows that the expected number of spills from a fully developed shale gas industry is very low indeed. This is consistent with onshore oil and gas industry experience over many decades, with very few environmental incidents. Indeed, in the latest Environment Agency league table for environmental management, our industry topped all other EA-regulated industries for sector performance."

ReFINE is primarily funded by energy company Ineos, with contributions from the Natural Environment Research Council, Environment Agency and the EU.

The findings have been published in the journal Science of the Total Environment.