Who gives a Frack about Oklahoma?
“You heard it coming, first came a thunderous boom and then the red earth shook hard, everything shook!” said Sandra Voskuhl, who for the past 76 years has lived in the rural town of Crescent, one of the boom towns of the fracking craze, which until recently has resulted in a rejuvenation of the area. But now the local residents may be about to count the cost.
Written by Automologist, MAC.
Reports from the US Geological Survey state that the central US State of Oklahoma has gone from registering two earthquakes a year to two a day. The scientists with the survey are laying the blame squarely on a controversial culprit – wastewater injection wells that accompany fracking operations.
For the layperson, it is important to know that Oklahoma sits well away from any known active seismic province or any other major fault lines, and thus it should be a rare event to experience even one or two tremblors that exceed a magnitude of 3.0 on the Richter Scale. But in 2014, the otherwise stable State in the mid-west shook a total of 585 times, which is more times than California, a State famously prone to seismic activity.
“It’s completely unprecedented,” said George Choy, a seismologist with the US Geological Survey.
Up to last month, Oklahoma has already experienced more than 600 quakes strong enough to rattle windows and rock cars, the biggest of which hit Crescent and measured 4.5 on the Richter scale.
“We need the oil for our workers and our economy,” said Voskhul. “But these earthquakes are a little scary.”
Hydraulic Fracturing (or fracking, as it is usually referred) is the process used when the oil or gas-bearing rocks are too tightly packed and lack the permeability for the valuable contents to freely flow into the well and thereafter be pumped out of the ground. The process shatters the rock below by injecting water and sand, and other chemicals into the rock, fracturing it and enabling the hydrocarbons to flow more freely to the surface.
In the past decade, this process has unlocked massive amounts of oil and gas, particularly in Oklahoma and Texas, and at least in part has led to the US of A being effectively self-sufficient in hydrocarbons with the resulting collapse in world oil prices.
The problem with fracking is the amount of the brackish water used for the fracturing that returns to the surface with the oil and gas. This waste product is then disposed of by injecting it into separate wells that are dug as deep as 1,500 metres below ground. It is thought that the introduction of this water can change the pressure along otherwise inactive fault lines, causing them to slip and thus make the earth shake. There is a debate amongst scientists over how the quakes are being caused and indeed just how strong they may get in the future. Some believe that the maximum Oklahoma will tremble will be 4.0 or 5.0 on the Richter scale, about the power needed to knock things off shelves, but do no or little damage to buildings. Others believe that it is only a matter of time before they experience a real jolter in the region of a 7.0, which would be strong enough to topple buildings.
“What’s at risk is that when you put water into the ground, it’s never going to come back out. You’re putting it in places it has never been before,” said Choy. “The bigger the volume, the greater the area will be affected. And we don’t know what the long-term effect will be.”
Residents of Oklahoma are rattled about the pace at which the number of earthquakes has increased in the State. Between 1975 and 2008, the maximum earthquakes of 3.0 or higher numbered less than three a year. Then things got a bit more shaky with 20 in 2009, 35 in 2010, 64 in 2011, 35 in 2012, 109 in 2013 and 585 in 2014.
“We are the only State where once this problem came up, we just kept going (with fracking),” said Johnson Bridgwater, the executive director of the Oklahoma chapter of the Sierra Club, a prominent environmental group. “We want public safety to come first, rather than treating this State as a giant lab.”
Oklahoma has an absolutely enormous oil and gas industry, and has had for more than 100 years, with pipelines and refineries and storage facilities dotted all across the State and in particular between Oklahoma City and Ponca City to the north. In the same area, there are at least 4,500 disposal wells.
State Government officials are now scrutinizing the operations of the disposal wells to ensure that they do not go too deep nor dispose of too much water; some operators have been told to reduce the amount of water being disposed of in this manner, particularly in what is known as the Arbuckle rock formation, which is deemed most at risk due to the “unique geological nature” of the formation. In addition to this, three wells have been closed after two quakes measuring 3.5 and 4.1 struck near the town of Cushing, which has one of the largest crude oil storage facilities in the world.
“We are hopeful that the actions taken by the Corporation Commission will have a significant impact on seismicity, but the process is ongoing and we’ll continue to evaluate the results that we’re getting now and potential future actions,” Alex Weintz, a spokesman for the State Government told reporters.
Unfortunately, the Sierra Club insists that much more needs to be done and has called for a moratorium on wastewater injection wells in the 21 Oklahoma counties identified to be most at risk, which, of course, is a very good idea.