Kristina Baum (EPW) – 202.224.6176

Donelle Harder (EPW) – 202.224.4721

Inhofe Corrects the Record on How Many Counties Will Be Out of Attainment Under New Ozone Standard 

WASHINGTON – U.S. Sen. Jim Inhofe (R-Okla.), chairman of the U.S. Senate Environment and Public Works (EPW) Committee, released a statement following today’s hearing to correct the record on EPA’s anticipated tightened ozone standard:

“Should EPA move the ozone standard down to 70 ppb, there could be 499 directly-monitored counties out of attainment,” Inhofe said. “In EPA’s proposal, they claim nine counties outside of California would violate 70 ppb in 2025, however, not every county in America has an EPA-designated monitor in them.  In fact, less than a third of the counties in the U.S. have EPA monitors.  To assert that only nine out of 3,100 counties in America would be pushed out of attainment under the 70 ppb standard would be factually inaccurate.  It is unarguable that tightening EPA’s ozone standard to 70 ppb would have significant detrimental impacts to our economy.  The price tag that comes along with tightening the ozone standard still boasts the most expensive regulation in U.S. history, even at an anticipated 70 ppb.  Let’s keep the facts straight, and keep our economy from footing the bill.”


EPA makes designations based off of the most recent, three-year span for which they have complete data from monitors and surrounding areas. In areas where there are no monitors, EPA uses modeling to determine whether the area meets the standard. In the proposal, EPA claims only 9 counties except for those struggling in California will fully comply with a new standard of 70 ppb by 2025. However, this number only acknowledges counties that have an EPA-designated monitor in them and does not include the possibility that adjacent counties with clean air may be pulled into nonattainment due to proximity or inclusion in the CBSA. EPA calculates impacts on California separately from the rest of the country, due to its abhorrent air quality, which currently has seven counties that are exempt from complying with the standard for up to 20 years.

In the proposal, EPA assumes that multiple regulations are fully implemented by 2025 and will contribute to counties attaining a standard of 70 ppb:

  • Tier III and other mobile source-related standards for vehicle emission control requirements
  • Mercury and Air Toxics Standards
  • Requirements to reduce the interstate transport of ozone
  • Regional Haze Best Available Retrofit Technology Emission Standards
  • Emissions Standards for Reciprocating Internal Combustion Engines
  • Emissions Standards for Industrial, Commercial, and Industrial Boilers,
  • The Clean Power Plan

As required in the Clean Air Act, the Ozone NAAQS will be up for review in 2020, yet EPA chooses 2025 as the most favorable snapshot for the maximum number of counties to achieve full implementation of the above regulations and the ozone rule.  

On June 3, the U.S. Senate Environment and Public Works Committee held a hearing entitled, “Challenges and Implications of EPA’s Proposed National Ambient Air Quality Standard for Ground-Level Ozone and Legislative Hearing on S. 638, S. 751, and S. 640.”