Phoenix Area’s Bad Air Tied to Storms

Michelle Ye Hee Lee
Arizona Republic

By most accounts, it will require a “herculean effort” to gather necessary documentation to prove to the federal government that the violations were caused by natural events, not man-made ones.

The U.S. Environmental Protection Agency relies on documentation submitted by states to determine whether to dismiss violations of dust-pollution standards as “exceptional events” – meaning that while proper controls are in place, violations still occur because of natural events beyond a state’s control.

So far this year, dust levels at monitors across the Valley exceeded federal limits 85 times. In many cases, multiple violations happened on the same day, but at different monitor locations.

Local air-quality agencies are unanimous in their belief that 84 of those cases were exceptional events that could be blamed on natural conditions. But to prove it generally would require 60 to 70 pages of documentation for each violation, officials said. A variety of data needs to be presented, including maps, satellite images, monitoring data and radar and meteorological information.

Local officials want to document what they think is the real culprit: several huge dust storms that blanketed the Valley with so much dust this year that they made national headlines.

And because of the Valley’s dry monsoon this year, local officials argue that there was not enough rain to clear the layers of dust, leaving it lingering on the ground and in the air for days.

The combination of dust storms and the lack of rain this monsoon has created atypical dust conditions in the region, said Colleen McKaughan, associate director of the air division at EPA Region 9.

“It’s an easier task when you have the kinds of haboobs that happened this summer,” McKaughan said. “They were quite clearly exceptional events. But where the documentation becomes important is when the day is not a haboob (day), yet someone wants to call it exceptional.”

If local officials cannot gather the documentation needed to explain the high number of exceedances to federal regulators, then it could be difficult for the region to meet its goal of three consecutive years in compliance with federal dust-pollution standards. Failing to do so could jeopardize federal funding for transportation projects in the state.

The region is in its third year trying to comply with federal standards for PM-10 particulate levels. PM-10 particles are large dust particulates that are one-tenth the width of a human hair.

There were 25 PM-10 exceedances in 2009, but none in 2010. Yet the 2011 exceedances already are the most since the EPA implemented PM-10 standards in 1987, according to the Maricopa Association of Governments, a coalition of local governments that serves as a planning agency for the Greater Phoenix area.

The Arizona Department of Environmental Quality is responsible for submitting documentation to the EPA to prove the region’s case. By MAG’s calculations, the workload for ADEQ staff members would equate to 1,019 workdays.

The ADEQ has asked the Maricopa County Air Quality Department and MAG to help it compile technical documentation. The three agencies are responsible for planning, regulating and enforcing air quality in the Valley.

“The trouble for us is, this monsoon season has been problematic,” said Eric Massey, the ADEQ Air Quality Division director. “(We’ve had) six of the really large, I’d almost call them epic, dust events, including the ones that made national news.”

MAG and the county Air Quality Department have the data and technical expertise that could help lighten the burden on the ADEQ staff members who are responsible for compiling documentation for exceptional events across the state, Massey said. Both agencies said they are willing to lend a hand.

“We do certainly agree that it’s a significant workload, to put it mildly,” said Jo Crumbaker, policy advisor for the county Air Quality Department.

Officials from the ADEQ, MAG and county Air Quality Department say this year’s onerous situation for local agencies proves that the EPA’s exceptional-events rule is not entirely applicable for Western states that tend to have high dust levels.

The EPA’s exceptional-events rule was released in 2007. This May, the EPA released a draft guidance document in an effort to clarify the exceptional-events requirements. Currently, the EPA is soliciting local governments’ comments on the draft guidance.

Massey said the ADEQ has been contacting the EPA since 2009, asking them to amend the rule or release guidance.

“While EPA’s guidance is meant to streamline the rule, we’re not sure if it’s helped,” Massey said. “Most of the Western states’ air directors do not feel the exceptional-events rule has been appropriately applied in our states.”

MAG said the agency hopes to see some amendment or change to the exceptional-events rule, if only for the Western states. One suggestion is to determine exceptional events on the state level, in consultation with the EPA.

“The thinking is, states are familiar with their own meteorology and the exceptional events that are happening in the state,” said Lindy Bauer, MAG environmental director.

McKaughan said changes to the exceptional-events rule would have to be a national decision. She noted the rule is set up by Congress to apply to all states, and that the EPA put the draft guidance up for comments so that states could give feedback on parts of the rule with which they may have issues.

“It’s not like we can say, ‘OK, skip the requirement,’ ” McKaughan said. “We can’t. The rule has several requirements. People have to meet them. We’re trying to explain how to meet them. We know it’s not easy but I don’t think we can just decide that the rule doesn’t apply, or some aspect of the rule doesn’t apply. That doesn’t seem to be appropriate, either.”