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Two new members of the Senate Democratic leadership team—Sens. Elizabeth Warren and Amy Klobuchar—are pushing the Environmental Protection Agency in separate directions as the agency works to complete its major regulation to cut carbon emissions from power plants.

Warren, who will act as a liaison to progressive groups for Senate leadership, wants the EPA rule to cut pollution more deeply. Meanwhile, Klobuchar—the incoming chair of the Senate Democratic Steering Committee—wants to slow down the process, saying the regulation imposes emissions-cutting mandates on states too quickly.

Both senators signed letters to EPA from separate coalitions of lawmakers this week. And while neither Warren nor Klobuchar signed the letters in their official leadership capacity, the dueling efforts nonetheless highlight competing goals in the Democratic ranks when it comes to the regulation at the heart of President Obama's climate agenda.

Warren joined 10 other generally liberal Democrats in a letter sent to EPA this week suggesting changes that "can, and should, achieve even greater emissions reductions." EPA's draft plan seeks to slash power plant emissions nationwide by 30 percent by 2030, with varying state-by-state mandates.

The letter, spearheaded by Sens. Jeff Merkley and Brian Schatz, pushes for various changes in the way EPA gauges the potential of renewable energy to displace fossil fuels. It also argues that EPA's energy-efficiency growth targets should consider a wider array of energy-saving options available to states.

In a separate letter, Klobuchar joined five red-state Democrats to call on EPA to relax some requirements on states.

That letter doesn't challenge the overall 30-percent target, but it asks EPA to scuttle the proposal's interim 2020 emissions cuts, arguing that the near-term pollution reduction mandate "does not accurately reflect the lead time needed for necessary infrastructure investments and upgrades."

The letter, which was spearheaded by Sen. Claire McCaskill of Missouri, was also signed by Sens. Joe Manchin of West Virginia, Joe Donnelly of Indiana, Heidi Heitkamp of North Dakota, and Mary Landrieu of Louisiana. Their letter says that each state should include its own "glide path" toward its 2030 requirements in the plans it submits to EPA, rather than working to meet EPA-imposed 2020 emissions-cutting mandates. The letter also says the rule, which EPA hopes to complete next summer, does not give states enough time to craft the emissions-cutting plans they must submit to EPA once the rule is finalized.

Environmentalists are criticizing the letter from McCaskill that Klobuchar signed.

"If we wait until 2030 to reduce carbon pollution fueling global warming, too much carbon will have been released into the atmosphere, making the reductions needed in later years more difficult. That may be one reason why EPA front-loaded many of the emissions reductions in their proposal," said Julian Boggs, who directs the global warming program at the group Environment America.

Boggs added that he's "very disappointed to see Amy Klobuchar calling for delaying emissions [cuts]," given her prior advocacy on fighting climate change. Both Warren and Klobuchar are members of the Senate Climate Action Task Force that formed in early 2014.

This article is from the archive of our partner National Journal.

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