Nature & Environment

Man-Made Earthquakes Put Millions of Americans at Risk

Sam Dastidar
First Posted: Apr 02, 2016 05:41 AM EDT

Man-made earthquakes have found their way in the list of the 2016 earthquake forecast for the Central and Eastern United States (CEUS) that has been released recently by the US Geological Survey (USGS). It was found that a population close to 8 million is prone to manmade earthquakes caused by the disposal of wastewater and gas and oil drilling.

Induced seismicity, which makes an area vulnerable to earthquakes, is on the rise in the Central and Eastern US, particularly in Texas, Kansas and Oklahoma. The novelty of the phenomenon is making it harder for regulators to come up with a conclusive solution to contain earthquakes attributed to human activity.

Drilling companies are left with tons of chemical and wastewater that come up to the earth's surface, along with gas and oil, during the drilling process. For the past many years, the wastewater has been taken care of by pumping it back into the deep underground. In recent years, the gradual improvement and advancement of drilling mechanisms has meant the ability to drill wider and faster. This has translated into a higher rate of underground wastewater disposal by drilling corporations.

In Kansas, there is a direct relation between underground disposal of wastewater and earthquakes. The state, which used to previously witness not more than four earthquakes greater than 2.5 magnitude annually between 2000 to 2013, saw an increased jump in seismic activity in the following year. The figures shot up to 154 earthquakes in 2014, nine of which measured more than 3.5 on the Richter scale.

A solution to the problem is not, however, completely lacking. In fact, there has been a success rate in certain parts of CEUS in containing the artificial disaster, particularly in Kansas itself.

In March 2015, following the alarming rise in man-made earthquakes, the state regulators ordered drilling companies to reduce their underground wastewater injection. The result was a noticeable fall in the number of earthquakes, particularly in Harper and Sumner counties, that share a close location with the scene of heavy duty drilling and underwater injection. Reduction in the depths of wastewater disposal also led to similar results in Oklahoma, though the regulators in the state did not put a cap on injection volumes or rates.

The UGCS suggests that the real solution lies in constant scientific research and updates that take changing variables into account. In addition, Ryan Hoffman, director of the Kansas Corporation Commission, feels that the problem should be tackled on a state level than on a national one, as each region is subjective to its own set of challenges. For now, however, the two hazard models implemented in Kansas and Oklahoma for containing man-made earthquakes can be the key to reducing disasters in other regions.

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