WASHINGTON — Arkansas’ power sector would be required to cut carbon-dioxide emissions nearly in half by 2030 under a draft rule unveiled Monday by the Environmental Protection Agency, but it is unclear how the change would affect the White Bluff plant near Jefferson.

WASHINGTON — Arkansas’ power sector would be required to cut carbon-dioxide emissions nearly in half by 2030 under a draft rule unveiled Monday by the Environmental Protection Agency, but it is unclear how the change would affect the White Bluff plant near Jefferson.

The proposed rule is directed squarely at the nation’s coal-fired power plants that are the single largest producer of carbon emissions that contribute to climate change. The goal is to reduce annual CO2 emissions by 30 percent by 2030.

"Today climate change — fueled by carbon pollution — supercharges risks not just to our health, but to our communities, our economy and our way of life," EPA Administrator Gina McCarthy said Monday morning.

EPA has set state-specific targets in the 645-page document but is allowing some flexibility in how states will achieve those reductions.

"We’re very glad EPA is going to give states a lot of flexibility. We want to do this from a state perspective," said Teresa Marks, director of the Arkansas Department of Environmental Quality.

Marks said her agency is "slogging through" the draft rule and will likely submit an official comment during the 120-day public comment period. EPA isn’t expected to issue a final rule until next year.

The Arkansas Public Service Commission and ADEQ have already set a June 25 meeting in Little Rock for state stakeholders to discuss the EPA draft rule and how to implement it in the state.

"There is a long road ahead of us as far as working out a plan," Marks said.

Arkansas is among about 20 states that rely heavily on coal-fired power plants to meet their electric needs.

The White Bluff coal-fired power plant is 57 percent owned by Entergy Arkansas Inc. and 35 percent owned by the Arkansas Electric Cooperative.

Entergy spokeswoman Sally Graham said Entergy is just beginning the review process of EPA proposal and it is unclear how it would affect the plant, in part because it is still unclear how it will impact the state as a whole.

"On impacts to White Bluff, this EPA proposal is not a unit-by-unit standard," Graham said Monday afternoon. "The standard is an average for the entire state, and the state will go through a process of determining how to meet the EPA standards. … Arkansas should get credit for Entergy’s nuclear generation. Right now it’s unclear how our nuclear generation is going to be treated. We think emissions-free nuclear power should be a part of the process."

In 2012 Arkansas power plants that would be covered by the rule produced about 36 million metric tons of carbon-dioxide emissions. EPA says that translated into 1,640 pounds per megawatt hour of electricity produced in 2012. The Arkansas plan would be to reduce that to 910 pounds per megawatt hour by 2030.

EPA’s figures do not factor in most of the electricity produced through Entergy’s nuclear power plant, which produce no carbon emissions. With the nuclear plant were included, carbon emissions from Entergy’s Arkansas facilities today would be 767 pounds per megawatt hour, according to Chuck Barlow, vice president of environmental strategy and policy for Entergy.

Barlow said the company would be reviewing the details of the draft proposal over the coming weeks to determine how it may impact Arkansas and other states where Entergy operates.

"We really have to sift through and digest it," he said.

Barlow said that the company is looking forward to continuing the conversation with EPA on how to address carbon emissions.

"They have done a good job of reaching out and talking to people about this rule and we are going to continue to talk to them," he said.

The draft rule has sparked a new round of controversy between environmentalist and business groups over government efforts to reduce greenhouse gas emissions. And, the rule is being used as fodder in mid-term elections — particularly in places like Arkansas where Republicans hope to win a U.S. Senate seat.

Sen. Mark Pryor, D-Ark., issued a statement expressing "serious concerns" that the proposal would "undermine the affordable and reliable electricity Arkansans currently enjoy."

Sen. John Boozman, R-Ark., and Rep. Tim Griffin, R-Little Rock, also issued statements Monday opposing the draft rule, saying it would raise electric rates, cost jobs and do little to reduce carbon emission globally.

Rep. Tom Cotton, R-Dardanelle, announced plans to co-sponsor legislation that would block the EPA proposal.

"The power plants regulations announced by EPA today will have a devastating impact on Arkansas’ economy. This regulatory assault on our energy industry must be stopped," he said.

Cotton, who is challenging Pryor, also issued a statement through his campaign blasting Pryor for voting to "rubber-stamp Obama’s nomination of radical EPA head Gina McCarthy, who is issuing these regulations."

The Republican National Committee and National Republican Senatorial Committee also issued statements blasting Pryor for failing to stand up to Obama’s "job killing, rate-hiking regulations."

Pryor has voted to block EPA from moving forward with the regulations. He also signed onto a letter last week urging McCarthy to consider more appropriate ways to regulate carbon emissions that would encourage development of clean-burning coal plants.

McCarthy, who worked for Republican administrations in Massachusetts and Connecticut, was confirmed as EPA administrator last July on a 59-40 Senate vote. Six Republicans backed her.

Glenn Hooks, chapter director for the Arkansas Sierra Club, praised the Obama administration’s effort to reduce carbon emissions from coal-fired power plants.

"By cleaning up and modernizing our aging, dirty power plants, we will begin to clean up our air, cut pollution-related illness and curb the worst effects of climate disruption," he said.

Hooks said that 85 percent of the carbon emissions in Arkansas come from five coal-fired power plants — three of which were built more than 30 years ago and could be shuttered as the state turns to cleaner energy sources and reduces demand through conservation.

"If the state focuses on those three plants they will readily comply — in big contrast to the doom and gloom and scare tactics put out by the fossil fuel industry," he said.

The U.S. Chamber of Commerce’s Institute for 21st Century Energy estimates that the regulation would cost the economy 224,000 jobs and $289 billion in higher electricity costs through 2030.

The National Rural Electric Cooperative Association issued a statement expressing its disappointment with the EPA draft rule saying it will likely force power plants to close and increase electricity prices for consumers.

"New EPA regulations that add to the price of electricity have serious consequences for our communities, jobs and families," said Jo Ann Emerson, the association’s CEO.

Marks said that there is a concern that electricity rates could increase but that Arkansas officials will take that into consideration as they develop a plan to meet the EPA requirements.

"That’s one reason we are glad we have two years with the possibility of an extension to look at this plan," she said. "We will be considering how we can have the least impact on consumers and rate payers. Nothing will take place immediately. We have time and will take a lot of input from stakeholders."

— Commercial reporter Michael S. Lee contributed to this report