By Ben Geman - 06/12/12 03:53 PM EDT
The letter is also signed by the mayors of Boston, Seattle, Portland, Las Vegas, Phoenix, Philadelphia, Denver and a number of other cities. The municipal officials are backing emissions rules that EPA finalized late last year that require curbs in mercury and other air toxics.
The Senate is slated to vote in coming days on Sen. James Inhofe’s (R-Okla.) plan to overturn the rule. Many Republicans and industry groups say the rule will drive up power costs and harm the economy.
Inhofe and other critics call it part of a “war on coal.”
“It's time for the Senate to do its job and stop this regulatory nightmare,” Inhofe said when introducing his plan in February.