1. California attempted to impose reduced limits on CO2 emissions.
2. The Fed blocked the California rules.
3. Kansas refused a permit for a massive new coal-fired generating plant based on excessive CO2 emissions.
4. The US Supreme Court ruled that CO2 is a harmful pollutant that the law REQUIRES the EPA to regulate.
5. Among the rush to impose new regulations before the new administrations takes over is a regulation prohibiting the consideration of CO2 emissions in granting of licenses for new power plants.
CO2 is just one of the most harmful emissions from coal-fired power generation, but is essentially unregulated.
6. Congressionally passed laws called for gradual reductions in particulate emissions, with the next step to have come about now. The current administration rushed through a new regulation to retain the previous limits for "average particulate emissions" (think coal-fired plants that operate 24-7) but imposed new limits on "peak emissions" that could, if enforced, allow fines of up to $25,000 for individuals using a wood-burning stove, for each day that they exceed the average for their area.
This last bit put Anchorage Alaska on the "excessively polluted" list, along with about 40 other mostly low-average-emission areas; but exempted Houston Texas, where the average particulate contamination is very near the peaks for which people in Anchorage could be fined, from being required to do anything.