The onshore shale gas and oil revolution has transformed the fortunes of the domestic US petroleum extraction industry.
The current UK government hopes a similar revolution is possible here, but progress has been slow and hampered by the increasing ground swell of protest that now confronts pioneering companies like Cuadrilla.
We are assured by the Cameron Administration that the process of fracturing shales onshore is environmentally safe. And the companies purr assurances, as does UKOOG (UK Onshore Operators Association). Only to be expected.
In Q4 2013, Public Health England (PHE) said that studies in the US had suggested possible health risks from emissions and contaminated water supplies were “limited and uncertain”.
Just a few days ago, on July 24, the Government apparently dismissed a call by the United Nations to look again at its shale-related legislation.
For several years, Energy has from time to time reported on the shale-related outputs of various American universities on the basis that it is probably the only way in which anything resembling the truths of this industry will be brought out into the open.
Some of that output is troubling; and the latest research revelations from Stanford reinforce Energy’s conviction that the UK Government is either sleepwalking or plain doesn’t want to know.
So what is this latest output from US academia? And why should we all be concerned?
The purpose of the research by Stanford environmental scientist Rob Jackson is to try and minimise the risks of well fracking to underground drinking water sources.
Work just published in Environmental Science & Technology, finds that at least 6,900 oil & gas wells in the US were fracked less than 1.6km (1 mile) from the surface. And at least 2,600 wells were fracked at depths shallower than 914m (3,000ft), some as shallow as 30m (100ft).
According to Jackson, this occurs despite many reports that describe fracking as safe for drinking water “only if it occurs at least thousands of feet to a mile underground”.
The authors of the report in Environmental Science & Technology also estimated water use for hydraulic fracturing in each state. The states with the highest average water use per well were Arkansas, Louisiana, West Virginia and Pennsylvania.
Perhaps most surprisingly, the researchers discovered that at least 2,350 wells less than 1.6km (1 mile) deep had been fracked using more than 3.785million litres (1million gallons) of water each.
They report that shallower high-volume hydraulic fracturing poses a greater potential threat to underground water sources because there is so little separation between the chemicals pumped underground and the drinking water above.
“Shallow hydraulic fracturing is surprisingly common,” said Jackson.
He’s no green-hand. This guy is the Michelle and Kevin Douglas Provostial Professor in the School of Earth, Energy & Environmental Sciences, and a senior fellow at the Stanford Woods Institute for the Environment and the Precourt Institute for Energy.
As a result, he says that the places where hydraulic fracturing is both shallow and water-intensive “may need additional safeguards”.
For example, he pointed out that Arkansas had more than 300 wells fracked shallower than 914m, using an average of 18.9lmillion litres (5million gallons) of water and chemicals.
Other states that fracked wells shallower than 914m using more than a million gallons each included New Mexico (16), Texas (10), Pennsylvania (seven) and California (two).
Jackson has tracked the rapid shift towards US energy independence and the pressing questions swirling around fracking’s impact on water supplies.
He acknowledges that there is a lot at stake economically and sees his purpose as “trying to make the process (of fracking) as safe as possible”.
Although fracking in the US produces more than 378.5billion litres (100bn gallons) of wastewater per year, the process is said to need “significantly less water per unit of energy” than extraction and processing for coal and nuclear power, according to earlier research by Jackson.
As part of the so-called frack-water they inject into the ground, drilling companies use proprietary blends of chemicals that can include hydrochloric acids, toluene and benzene.
When wastewater comes back up after use, it often includes those and potentially dangerous natural chemicals like arsenic, selenium and radioactive radium drawn up from subterranean recesses.
According to Stanford material: “Because oil & gas companies must drill tens of thousands of new wells each year in the US to maintain production through time, groundwater contamination remains a possibility.
That said, using innovative techniques such as isotopic “tracer” compounds that distinguish the source of chemicals in well water, Jackson has not so far found evidence that frack-water contaminants seep upward to drinking-water aquifers from deep underground.
He has, however, shown that failures in steel and cement well casings nearer the surface are often to blame for leaks.
While much has been made of fracking’s potential impacts on water now, Jackson also wants to understand legacy effects like chemical leakage long-term.
“The public pays to clean up acid mine drainage today because of poor practices decades ago,” Jackson said. “What are we doing today that may cause problems tomorrow?”
In particular, he thinks that US States aren’t saving enough money to tackle future problems, choosing instead to spend their oil & gas revenues today.
While he notes that some countries, such as Canada, the UK and Germany, have instituted or are considering special requirements for shallow fracking wells, most US states lack additional oversight for such operations.
Only two US states, Colorado and Texas, have defined requirements for shallow hydraulic fracturing.
In the study, Jackson and his co-authors suggest shallow wells especially may warrant special safeguards like:
More information from operators about details such as distance between groundwater resources and potential fractures
State assessments of additional safety measures needed for wells fracked shallower than 914m.
A mandatory registry of shallow fracking locations
Full disclosure of chemicals used in fracking operations
Pre-drilling testing of nearby groundwater sources
Jackson noted a number of positive changes in the industry in the past few years.
For example, drilling companies are increasingly reusing and recycling their wastewater, even though the process is more expensive and labour-intensive than the standard approach of re-injecting it thousands of feet underground.
It is work such as this that provides pointers to what could happen in the UK where the Great British Public will be very hard to dupe.
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