Thursday, September 14, 2017

How Man-made Earthquakes Could Cripple the U.S. Economy

Massive tanks in Oklahoma brim with unrefined oil, but they weren’t designed to handle the rash of seismic activity caused by fracking-related activity

When Hurricane Harvey made landfall in Texas, U.S. oil refining plummeted to record lows. Now, nearly three weeks later, six key refineries remain shut down and an additional 11 are either struggling to come back on line or operating at a significantly reduced rate. That slowdown, coupled with predictions of decreased demand in the wake of Hurricane Irma and the devastating earthquake that struck Mexico last week, has shifted oil pressures in other places, too. And none may be quite as vulnerable as the tank farms in Cushing, Oklahoma.
Dubbed the “Pipeline Crossroads of the World,” Cushing is the nexus of 14 major pipelines, including Keystone, which alone has the potential to transport as much as 600,000 barrels of oil a day. The small Oklahoma town is also home to the world’s largest store of oil, which sits in hundreds of enormous tanks there. Prior to this recent spate of natural disasters, Cushing oil levels were already high. They’ve increased nearly a million barrels, to nearly 60 million barrels, since Harvey hit.
This concentration of oil, about 15 percent of U.S. demand, is one reason the Department of Homeland Security has designated Cushing “critical infrastructure,” which it defines as assets that, “whether physical or virtual, are considered so vital to the United States that their incapacitation or destruction would have a debilitating effect on security, national economic security, national public health or safety, or any combination thereof.”
The biggest potential cause of that incapacitation? According to Homeland Security, it’s not terrorism or mechanical malfunction. It’s natural disaster. And here’s the problem: When most of the Cushing tanks were constructed, the most logical cause of any such disaster seemed like a catastrophic tornado. No one anticipated swarms of earthquakes. But that’s what began occurring about five years ago, when wastewater injection and other fracking-related activities changed the seismic face of Oklahoma in dramatic fashion. Two hours before that deadly quake in Mexico, for instance, a magnitude 4.3 temblor shook Central Oklahoma, knocking out power for thousands. The earthquake, which had an epicenter just 100 miles northwest of Cushing, was the 186th quake in Oklahoma this year to register a magnitude 3.0 or higher.
This man-made seismicity has changed the landscape of Oklahoma significantly, from a state with one of the lowest seismic rates in the country to the most seismically active in the lower 48, says Ken Erdmann, senior vice president at Matrix Engineering, the firm that designs, fabricates and builds many of the tanks in places like Cushing. “It’s not natural. It’s not Mother-nature based.”
That’s a problem, he says, because the statistical analysis used to establish safe environmental loads is based on historical intervals—both the average and maximums of events like snowfall or wind or seismic activity.
“When those levels become man-made induced numbers,” says Erdmann, “statistics are no longer really relevant.”
But while the number of earthquakes and their intensity have increased in recent years, the strength of the regulatory apparatus in place to ensure their safety hasn’t kept pace. Oversight of the tanks has been left to a tiny agency buried inside the Department of Transportation that was never intended to serve this role. And the safety standards, which one earthquake expert calls the weakest permissible, were created by an industry trade group rather than the government agency. For those inclined to contemplate worst-case scenarios, the prospect of an earthquake rupturing the Cushing tanks would be an environmental catastrophe far greater than the Exxon Valdez spill.
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