Sen. Tom Carper led his colleagues May 2 in calling for Environmental Protection Agency Administrator Scott Pruitt to address the apparent conflict of interest regarding his participation in the review of EPA’s 2015 National Ambient Air Quality Standards for Ozone.

As attorney general of Oklahoma, Pruitt sought to overturn the 2015 Ozone NAAQS, which set stricter standards for pollutants considered harmful to public health and the environment.

Carper, along with Sens. Cory Booker, D-New Jersey; Kamala Harris, D-California; Edward J. Markey, D-Massachusetts; and Sheldon Whitehouse, D-Rhode Island, requested information on Pruitt’s efforts to mitigate the likely conflicts of interest.

The EPW members wrote, “In October 2015, you filed an action in the U.S. Circuit Court of Appeals for the District of Columbia (Murray Energy v. EPA) challenging the 2015 Ozone NAAQS on behalf of the state of Oklahoma. In the April 7 motion, the EPA not only seeks a delay in the litigation but also states that the agency ‘intends to closely review’ the rule.

“We all continue to believe that you should have committed to recuse yourself extensively from a number of matters during your confirmation process. Nevertheless, your anticipation of, and preparation for, both the filing of the motion in the D.C. Circuit and the intended review of the 2015 Ozone NAAQS should have triggered the more limited recusal policy to which you have already and repeatedly agreed.”

Prior to his confirmation as EPA administrator, Pruitt said he would “seek authorization [from the EPA’s Designated Agency Ethics Officer] to participate personally and substantially in particular matters involving specific parties in which [he] know[s] the state of Oklahoma is a party or represents a party.”

Over the last two months, Carper has led lawmakers in calling on Pruitt to address similar conflicts of interest regarding EPA’s review of the Clean Water Rule and the Clean Power Plan, both of which Pruitt sought to overturn as Oklahoma’s attorney general. Pruitt has yet to respond to either request.

Full text of the letter can be found at bit.ly/2pFb2gB.