Aiming to lessen the amount of wastewater flowing out of airports, the U.S. Environmental Protection Agency is proposing a new rule that would affect deicing practices at about 200 commercial airports in the U.S.

The new proposal would require the airports to collect and treat the wastewater associated with deicing fluid used for aircraft and runways. Airports would have the option of treating the wastewater on-site or sending it off to a treatment contractor or public works.

If put into effect, the rule would reduce deicing-related pollutants by 44.6 million pounds a year and cost about $91.3 million a year.

The intention of the rule is to keep the fluid from entering water systems where it could contaminate drinking water, reduce wildlife and have other negative effects on residential areas and parklands. 

The EPA estimates that, under the proposal, the six airports that are the biggest users of deicing fluid would need to install centralized deicing pads, while other airports that use less fluid could use other recovery methods.

Airports would need to collect varying amount of the wastewater: 60 percent for larger operations and 20 percent for airports that use lesser amounts of deicing fluid. The new rule would apply to airports that have deicing operations, have 1,000 or more annual jet departures and have 10,000 or more total annual departures.

The approximately 50 airports that use urea to deice runways would also need to switch to a different deicing fluid or take steps to reduce ammonia discharges that result from using urea.

The proposed rule will be up for comment once it is published in the Federal Register.

Another plan to lessen airport impacts was announced this week when eight major airlines said they will start using synthetic biodiesel to run their ground service equipment at Los Angeles International Airport starting in 2012.

_{Airplane deicing - CC license by PhillipC}