The US Environmental Protection Agency (EPA) is accepting public comment on its proposed rule to require airports to control wastewater associated with the deicing of both aircraft and the airfield at more than 200 commercial airports.
Airports that have deicing operations and more than 1,000 annual scheduled commercial jet departures would be subject to the proposed rule.
Theproposed rule would limit the amount of ammonia discharged from urea-based airfield deicers.
Airports could meet this requirement by simply not using urea-based airfield deicers, says Mary Smith, director of the engineering and analysis division in the EPA Office of Water. She adds that of the roughly 218 airports where the proposed rule applies, only 50 currently use urea-based airfield deicers.
In addition to the airfield component, the proposed rule would require certain airports to collect spent aircraft deicing fluid and treat the associated wastewater.
Smith says the aircraft deicing requirement would apply to the 110 airports with the most departures out of the 200-plus airports impacted by the overall rule.
From the 110 airports, the top 14 users of deicing fluid would be required to collect 60% of their aircraft deicing fluid.
Smith says that can be done by airports having a centralized deicing pad.
The remaining 96 airports that this portion of the proposed rule would apply to would have to collect 20% of their aircraft deicing fluid, which Smith says can be done with glycol recovery vehicles.
Published in the Federal Register last month, the proposed rule is open to public comment until 28 December.
"This isn't a final rule. [We] want to hear from the industry," Smith says.
However, the agency expects a deicing rule would take effect in mid-2010, at which point the EPA and states would incorporate the proposed requirements into their stormwater permitting requirements.
As airports renew their stormwater permits, the facilities would then have to meet the deicing requirements.
The proposed rule would mark the first national deicing standard for airports.
While the Airports Council International-North American (ACI-NA) has not submitted its comments yet, the association has some concerns about the rule.
Most ACI-NA members already have deicing plans and already meet state regulations that could impact deicing, ACI-NA senior director of environmental affairs Jessica Steinhilber says. Shedid not have an exact figure for the number of airports with deicing plans.
Developing a standardised requirement for diverse and varied airports is not an easy thing to do, she adds. For example, the land-constrained airports required to collect 60% of their aircraft deicing fluid could find that the location of a centralised deicing pad impacts how quickly aircraft can be deiced before takeoff, she explains.