By Erin McPike and Holly Yan

(CNN) -- President Barack Obama is using his executive authority to take his strongest action yet against climate change -- proposing new EPA regulations.

The chief of the Environmental Protection Agency will announce a proposal Monday that will require power plants to cut their carbon emissions by 30% by 2030, a source briefed on the matter told CNN.

States will have a variety of options to meet the goal, the source said.

Some Republicans aren't happy, saying the requirement will kill jobs in the coal industry. But the White House says it's not just good for the environment, it will also be healthier.

"As president, and as a parent, I refuse to condemn our children to a planet that's beyond fixing," Obama said in his weekly address Saturday.

The costs

The U.S. Chamber of Commerce, a business federation, estimated the new regulations will cost the economy $50 billion a year.

"The Administration has set out to kill coal and its 800,000 jobs," Sen. Mike Enzi said in the GOP weekly address Saturday. "If it succeeds in death by regulation, we'll all be paying a lot more money for electricity - if we can get it."

But environmental advocates say such claims are exaggerated.

"This is something we can't put off, and the president deserves huge credit for making this his legacy," said David Doniger of the Natural Resources Defense Council.

Political impact

New EPA regulations could affect competitive Senate races in states with a significant coal industry, such as Kentucky, North Carolina and Colorado, where Democrats are trying to keep control of the upper chamber.

According to The New York Times, the proposed regulations take aim at the nation's more than 600 coal-fired power plants.

Under the proposed regulation, states will be given a wide menu of options to achieve the carbon emission cuts, according to The New York Times.

Instead of shutting down coal plants immediately, states would be allowed to cut emissions by making changes across their electricity systems --- such as by installing new wind and solar generation or energy-efficiency technology, the Times reported.

White House spokesman Jay Carney said last week that the president's proposal isn't just about the environment and health; it's also about making the country more energy independent.

CNN's Mary Grace Lucas contributed to this report.

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