The Environmental Protection Agency has told Oklahoma regulators to do more to protect the state from a surge in earthquake activity that scientists have linked to the underground disposal of oil and gas wastewater.
An EPA administrator sent a letter in November to the Oklahoma Corporation Commission, saying a magnitude 5.0 earthquake happened despite state and federal action to curb wastewater injection. The Frontier first reported the contents of the letter
The commission's response to the EPA said Oklahoma will continue to work with federal officials and made note of a governor's task force on wastewater.
Oklahoma Attorney General Scott Pruitt is President Donald Trump's pick to head the EPA. His nomination is awaiting Senate approval.
Environmentalists have criticized Pruitt for not doing more to reduce seismic activity in Oklahoma.