This is one of a huge number of environmental protection rules the Biden administration has restored. If you’re an American and want to keep these, it’s important to not just check your voter registration, but to actively volunteer, and if you can afford it, donate
How does it take 4 years to do this - just to have a potential republican presidency undo it a year or two later?
The US rulemaking process is designed to go slow, and Trump forced out most of the EPA staff.
It’s a lot easier to break things than it is to build.
For reference on why the staff thing is an issue, it currently takes ~18 months for the federal government to hire someone, which is why many departments are critically understaffed.