Date: February 1st, 2017
Explanation: Congressional action
Agencies: EPA
Two bills were introduced in the Senate (S.263) and House (H.R.806) to delay implementation of the Environmental Protection Agency (EPA)’s 2015 Ozone Standards. A full text of the Senate version is available here (both versions will likely be posted to Congress.gov in the next few days). While the standards that would be affected by this proposed legislation do not directly regulate greenhouse gas emissions, they do have significant greenhouse gas emission reduction co-benefits.
2015 National Ambient Air Quality Standards (NAAQS) for Ozone
In 2015, based on EPA’s review of the air quality criteria for ozone (O3) and related photochemical oxidants and for O3, EPA revised the levels of both standards. EPA revised the primary and secondary ozone standard levels to 0.070 parts per million (ppm), and retained their indicators (O3), forms (fourth-highest daily maximum, averaged across three consecutive years) and averaging times (eight hours).
While EPA did not quantify the greenhouse gas reduction co-benefits of this rule, it did recognize in an implementation memo that sources of ozone pollution may generate GHG emissions (e.g., motor vehicles) and thus actions to reduce ozone pollution will also have GHG co-benefits.