Some power plants were allowed to keep working even if they didn't follow all the rules. For example, the Colstrip Generating Station in Montana releases more harmful air pollution like lead and arsenic than any other similar plant in the U.S., according to the EPA. Other plants allowed to continue include the Coal Creek Station in North Dakota, which produces a lot of mercury pollution, and the Oak Grove plant in Texas, which also pollutes a lot.

Some of the biggest power companies in the country own the plants that don't have to follow the rules. These companies include Talen Energy, Dominion Energy, NRG Energy, and Southern Co.

These rules also apply to four power plants run by the Tennessee Valley Authority, which is the biggest public power company in the country.

The EPA said on Tuesday that the president's exceptions will make coal power stronger. This will help our country's electricity system work well, keep power costs low for Americans, and help the EPA improve our nation's energy safety.

Michelle Bloodworth, the head of a group that supports coal power plants, said Trump believes the country's coal power is "very important for keeping our electricity supply strong and safe, which is necessary for our economy."

She said the rules made by former President Joe Biden did not follow the Clean Air Act and used a wrong analysis of the data.

Bloodworth said that last year's mercury rule might have made many coal power plants close earlier than planned. He added that these plants are needed to keep the electricity system working well.

Environmental groups said it was wrong for Trump and the head of the EPA to allow these exceptions. They said this is because the technology needed for the new rules is not easy to find, and keeping the plants running helps national security.

"These permissions to pollute create a serious problem for federal laws that protect the air we breathe," said Maya Golden-Krasner, a lawyer at the Center for Biological Diversity, an environmental group. "Saying it's for national security to make people across the country breathe more harmful chemicals is wrong. This shows that the government cares more about companies making money than about the health of Americans and the environment."

Groups that protect the environment and health experts have strongly criticized the government's plan to let some companies avoid following rules that are meant to protect nature and people's health.

Critics say the new email address the EPA made for companies to ask for special permission is a "polluters' portal."

Exemptions can be given for nine environmental rules, including rules about mercury and other dangerous air pollutants. These pollutants can harm your brain and cause problems for babies before they are born.

Last week, Trump signed several orders using his power in emergencies. He let some older coal power plants, which were supposed to close, continue making electricity. This was to help with the increasing need for power in the U.S., as more data centers, AI, and electric cars are being used. Trump also told government groups to find coal on government land, make it easier to mine coal, and focus on renting land for coal mining.

Trump, who is a Republican, has often said he wants to help the coal industry.