In 2010, the year Oklahoma Attorney General Scott Pruitt (R) was elected, the state experienced 43 earthquakes.

In 2016, the year Pruitt was nominated by President-elect Donald Trump to run the U.S. Environmental Protection Agency, Oklahoma registered 518 earthquakes. Sixteen of them were magnitude 4.0 or greater, including the state’s biggest ever, a 5.8 quake that rattled houses from their foundations.

There is no question these earthquakes are caused by wastewater injections from oil and gas operations. Over the past decade, the state’s biggest industry has transitioned to hydraulic fracturing technology, which uses massive amounts of chemical and sand-laced water, injected at high pressure into the ground. The industry boomed — but it also was left with significant amounts of unusable water. The cheapest, easiest disposal method is to simply inject the water back into the ground.

As state attorney general, Pruitt is responsible for advising and defending state agencies on legal issues. He is also responsible for protecting Oklahoma citizens. But under his watch, earthquakes grew exponentially, in both size and frequency. Oklahoma’s ground literally can’t take the wastewater. The pressure is chipping away at the state’s fault line. And some legal experts say Pruitt could be on the hook for a potentially devastating earthquake.

“The only person in the state of Oklahoma who had the authority to do anything about this was the attorney general,” Paul Bland, executive director of Public Justice, a nonprofit advocacy organization, told ThinkProgress.