Dive Brief:

• The Environmental Protection Agency (EPA) will release final regulations on ground-level ozone today, the pollutant that is the main ingredient in smog.
• The new rules will tighten the ozone standard from 75 parts per billion (ppb), set by the George W. Bush administration, to 70 ppb. Environmentalists and public health officials had pushed for a stricter standard between 60 and 65 ppb, the range EPA proposed in its draft rule last year.
• Industry groups and fossil fuel generators have decried the rule, calling it duplicative, costly and unnecessary.

Dive Insight:

The EPA’s finalized ozone rule was widely expected to please no one — and on that count, the agency didn’t disappoint.

The 70 ppb standard represents a weaker regulation than EPA proposed last year, when it released a draft rule that would have tightened the standard to between 65 and 70 ppb.

Those tighter standards were based on findings from the agency’s scientific panel, which recommended a standard as low as 60 ppb to protect public health. On hot, sunny days, ground-level ozone mixes with other pollutants and reacts with the sun to form smog, which can cause serious respiratory and heart problems in vulnerable populations.

Since the draft proposal was released, however, industry groups and generators have fought the rule, launching a public relations campaign against tightened standards and joining with conservative lawmakers to press the agency and White House to reconsider.

The new 70 ppb standard, the weakest possible in the range given by the EPA’s science committee, suggests the industry was at least somewhat successful in its lobbying efforts, the New York Times reports.

David Baron, managing attorney for Earthjustice, told reporters on a Monday press call before the rule was released that his organization would likely sue the EPA if the standard was set at 70 ppb.

“Setting the standard at 70 parts per billion would be nothing short of a betrayal of the Clean Air Act's promise,” he said, according to the Huffington Post.

The rule’s impact on the utility sector is expected to be less significant than on the manufacturing or automobile industries, since the dirtiest of the nation’s coal plants have largely already been forced offline or installed pollution scrubbing equipment as a result of the EPA’s Mercury and Air Toxics Standards (MATS).

Update: The EPA has released a handy map outlining every county in the U.S. not compliant with a 70 ppb ozone standard.