Airplane Deicer Gets Closer Look

A chemical used by Alaska aviators to prevent their aircraft from icing up in the winter is getting new scrutiny from environmental regulators.

The state plans to adopt a rule that would classify the anti-icing fluid, sprayed on planes before they take off, as a contaminant that could require an industrial cleanup.

State officials will not use the cleanup guidelines to regulate routine use of the honey-like fluid, called propylene glycol, at airports, they say. The fluid, sprayed from trucks, drips all over the runways at the Ted Stevens Anchorage International Airport during the winter.

Instead, the rules will apply to "significant" events, such as a several-hundred-gallon spill from an overturned truck that leaks into soil, said Bill Janes, a supervisor with the Alaska Department of Environmental Conservation's contaminated sites program.

But some local aviators such as Mark "Woody" Richardson of Grant Aviation think the proposed rules are bizarre. Hundreds of thousands of gallons of the fluid, mixed with water, are sprayed on planes each winter, he said.

"What's the difference between spilling and dripping?" Richardson asked in a recent interview.

The Alaska Air Carriers Association, a trade group of airlines, also is critiquing the proposal, which is out for public comment this month.


Propylene glycol has enjoyed a benign reputation for decades.

The fluid is considered much less harmful than another common fluid, ethylene glycol, which is used to melt ice and snow off aircraft. Propylene glycol is also used as an additive in cosmetics and such processed food as ice cream and carbonated drinks, prompting disapproval from some consumer activists.

The Federal Aviation Administration requires air carriers to de-ice their planes to prevent accidents.

Last year, air carriers at the Anchorage international airport sprayed more than 380,000 gallons of propylene glycol and about 114,000 gallons of ethylene glycol, according to airport officials.

Most of the de-icing fluid drains to Cook Inlet or is mopped up, but some drains into Lake Hood, airport officials said Friday.

Propylene glycol can harm fish when it leaks into streams or lakes. As the fluid biodegrades, it reduces the amount of oxygen in the water, according to the U.S. Environmental Protection Agency. That is a likely culprit for a few fish kills that have occurred at airports, the EPA says.

The fluid's aquatic harm isn't the reason state officials want to add the fluid to their list of regulated chemicals.

The state wants to list the chemical and establish human health-based cleanup levels so it will know how much to remove from a contaminated area after a spill, Janes said.

But the aquatic concerns are driving the EPA to consider new regulations of its own.


Federal regulators have informed the airline industry that they will propose to limit effluent from anti-icing and deicing fluids next year.

The rules will likely be finalized in 2009, according to an EPA Web site set up to give background about the agency's research on the de-icing fluids and its decision timeline.

Officials at the Anchorage airport said Friday they are trying to get out ahead of the new federal rules.

Over the past few years, the airport has diverted most of the de-icing fluid that used to drain to Lake Hood, said Shane Serrano, the airport's environmental program specialist.

The airport's water pollution permit doesn't limit the amount of de-icing fluid that drains to Cook Inlet, but the EPA's future guidelines could change how the airport is regulated, he said.

Theoretically, the rules could also have a bigger impact on rural airports. Many rural air fields do not have a drain system for collecting the de-icing fluid or a system to mop it up, state regulators said.

"We recognize that money is short and we cannot suddenly start requiring infrastructure at rural airports," Janes said.

Find Elizabeth Bluemink online at or call 257-4317.

de-icing: Find out more about the state's proposal to change its cleanup regulations and the U.S. Environmental Protection Agency's plans to regulate de-icing fluids. To comment on the proposal, see the links attached to this story at The comment deadline is Monday, but regulators said it will probably be extended.