"An enforcement breakthrough a decade in the making was unveiled in December: Three manufacturers of a sooty oil-based product known as carbon black had agreed to slash air pollution by thousands of tons each year.

But there was a twist.

As they cracked down on those three firms, U.S. EPA and the Justice Department were quietly angling to ease up on two others.

Cabot Corp. and Continental Carbon Co. had previously reached their own settlements with the government. In what former EPA officials describe as an unusual move, federal regulators have agreed to give them years longer to install new pollution controls, according to court filings."

Sean Reilly reports for Greenwire March 26, 2018. [2]