I definitely challenge people. But hopefully, I am working harder than anybody else, and so people won't resent the fact that I want them to work hard, as well.

I think that one of our most difficult international challenges is clearly climate change and making sure that the Paris agreement goes forward. While I think the international community understands that President Trump is not taking the same position as President Obama.

EPA gets to set a standard for new. For the existing, EPA sets guidelines for what we think is appropriate, but then states develop plans that work for them, taking into consideration their specific energy mix.

I cannot shy away from controversy. I don't know if it's my Irish blood, but I love it.

There is no threshold level of fine particle pollution below which health risk reductions are not achieved by reduced exposure.

But I will tell you that I didn't go to Washington to sit around and wait for Congressional action. Never done that before, and don't plan to in the future.

But just [proposing the standard] puts companies on notice that if you're looking to construct a new natural-gas or coal facility, you really need to pay attention to these. This is what they should be designing new facilities toward as soon as this proposal hits the streets.