(a) Aircraft deicing. Except for new airports located in Alaska, all new sources located in an area that, at the time of construction, had more than 3,000 annual heating degree days, and are estimated, within five years of commencing operations, to exceed 10,000 annual departures, must comply with the following requirements upon the date the facility exceeds 10,000 annual departures. New source performance standards that apply prior to that date, new source performance standards for sources that project they will not exceed 10,000 annual departures within five years of commencing operations, and new performance standards for airports in Alaska, are beyond the scope of this regulation and shall be determined by the permit authority on a site-specific basis.

(b) Airfield pavement deicing. There shall be no discharge of airfield pavement deicers containing urea. To comply with this limitation, any new source must certify annually that it does not use airfield deicing products that contain urea or alternatively, airfield pavement discharges at every discharge point must achieve the numeric limitations for ammonia in Table III, prior to any dilution or commingling with any non-deicing discharge.