Update (02/17/10): "Last-Minute Changes Will Improve Air Pollution Monitoring, EPA Says."

It’s looking more and more like the White House Office of Information and Regulatory Affairs (OIRA) overruled the EPA in a decision to place more air pollution monitors near major roadways.

On Monday, EPA finalized a rule which limits nitrogen dioxide exposure and sets up a monitoring network along heavily-polluted roads. The trigger for placement of a monitor is the population of a metro area. If the area has a population of 500,000 or more, it gets a monitor.

But originally, EPA indicated the threshold would be a population of 350,000. The change means 41 fewer monitors will be placed around the country. [I was wrong, see the update above.]

Based on documents in EPA’s rulemaking docket, we know that the change was made during the OIRA review of the draft of the NO2 final rule. We also know that at least one high-level EPA official was pushing for the lower threshold.

In an email dated Jan. 19, an EPA employee wrote, “We are willing to put forward an alternative threshold for the first tier of the near-road monitoring network for you to discuss with your management at your 2:30 meeting,” and then suggested the 500,000 population threshold.

What prompted this 11th hour policy change? Who knows. Semantically, “we are willing” suggests a certain level of coercion, but that’s mere speculation on my part.

The more interesting exchange came the next day when Lisa Heinzerling, EPA’s Associate Administrator for policy and an adviser to EPA Administrator Lisa Jackson, sent a follow-up email to OMB. It simply stated, in its entirety, “EPA does not support the alternative threshold described in the email below.” The email was in direct response to the EPA's employee's proposal, though the email itself was addressed to OIRA.

Despite Heinzerling’s clear protest, the threshold was raised. Sometime between Jan. 20 and Jan. 22, the day OIRA concluded its review of the NO2 rule, somebody changed his or her mind, or somebody was overruled.

We’re still investigating this, but if EPA was indeed overruled, it would be a clear-cut instance of political interference in an inherently scientific decision. Regulators need reliable data to enforce EPA’s new NO2 standard which, for the first time, targets short-term exposure to the pollutant. NO2 begins to wreak its havoc even in short bursts, causing respiratory illnesses “particularly in at-risk populations such as children, the elderly, and asthmatics,” EPA says. EPA describes the urban and near-roadway environments that will be closely monitored as “high-risk.” Given that information, EPA needs to go about its business monitoring pollution and rigorously enforcing the new standard. Instead, because of possible White House interference, the agency will have to operate with one hand tied behind its back.