Three California cities no longer have to track carbon monoxide pollution

The US environmental regulators are proposing to remove carbon monoxide monitoring and contingency plans for three urban areas in California. This means local officials in Chico, Modesto, and Stockton will no longer have to measure or plan for carbon monoxide pollution.

For decades, these cities had to keep measuring carbon monoxide levels and have plans ready in case pollution got too high. This rule change means they no longer have to do that. It effectively declares the problem solved in these areas, freeing up resources that were previously dedicated to monitoring and planning for this specific pollutant.