Career staff at the Environmental Protection Agency (EPA) have recommended the agency’s current ozone pollution standard be maintained, despite calls from Democratic elected leaders and environmental activists to further tighten regulations.

The issue has been fraught in the West where foreign pollution and higher elevation has made the challenge difficult, including the infamous “brown cloud” that is seen in the Denver area. But as Western Wire previously reported, major cities across the region have seen falling ozone levels. Denver along with Las Vegas, Dallas-Fort Worth, and Phoenix had fewer ozone days in 2018 according to an American Lung Association report.

In a 926-page Policy Assessment (PA), the staff at EPA said the national ambient air quality standards (NAAQS) should remain at 70 parts per billion (ppb) as it adequately addresses health issues and not lowered.

“Collectively, these considerations provide the basis for the preliminary conclusion that consideration should be given to retaining the current primary standard of [70 ppb] O3, as the fourth-highest daily maximum 8-hour concentration averaged across three years, without revision. Accordingly, and in light of this conclusion that it is appropriate to consider the current standard to be adequate, we have not identified any potential alternative standards for consideration in this review,” the assessment stated.

Karen Kerrigan, President and CEO of the Small Business & Entrepreneurship Council, told Western Wire that a new standard would have compounded difficulties many states already faced with the 2015 standard.

“Compliance with the 70 ppb standard in itself is going to be very difficult for regions of the country to attain,” she said. “Lowering the standard further would vastly move the goal posts, tie up important infrastructure projects, raise costs and hurt the economy.”

“Hopefully the EPA’s plan to keep the current background ozone standard at 70 ppb will bring some certainty to state and local entities and businesses that are caught in the crosshairs of what is essentially federal zoning,” Kerrigan added.

The EPA has tightened the ozone standard over the past 40 years. It was as high as 120 ppb in 1979 before being lowered to 80 ppb in 1997. Since then, it has fallen further to 75 ppb in 2008 before the current standard was set in 2015 at 70 ppb.

When then-EPA Administration Gina McCarthy set the current level in 2015, she noted it was a safe level for children in urban areas, as cities see the highest ozone levels due to increased traffic.

“The Administrator noted that a revised standard with a level of 70 ppb was estimated to protect the vast majority of children in urban study areas (i.e., about 96% to more than 99% of children in individual areas) from experiencing two or more days with exposures at or above 60 13 ppb (while at moderate or greater exertion),” the PA recalled.

The PA will serve as a resource to the independent Clean Air Scientific Advisory Committee (CASAC) which provide recommendations to the EPA Administrator, Andrew Wheeler. Ultimately, however the PA states that final NAAQS decisions “will reflect the judgments of the Administrator.”

InsideEPA reports the CASAC will hold a meeting in Cary, N.C. from December 3-6 to review the findings of the PA and that public comment will be open until December 16.

Ozone has long been a contentious issue in Colorado where the population density and traffic congestion in the Denver metro area sometimes leads to elevated ozone levels during the summer. Much of Colorado’s ozone pollution is from out-of-state and foreign sources and settles alongside the mountains of the state’s Front Range.

Former Gov. John Hickenlooper cited those challenges to obtain a waiver from the EPA for Colorado’s nonattainment status, but current Gov. Jared Polis reversed course earlier this year to justify tougher environmental regulations. Western Wire has previously reported on Polis’ decision that could cost the state federal highway funds and tougher permitting processes for manufacturers.

Colorado has made progress in fighting in progress thanks to collaborative work among the EPA and the state’s public health department, but the move by Polis to force stronger action potentially disrupts the process. However, the recent PA from the EPA could give the state more room to meet the threshold.

Environmental activists have also pressed Colorado and other states to dramatically tighten their ozone regulations. WildEarth Guardians has filed lawsuits EPA alleging the agency isn’t doing enough to address the issue.