Section 260. Sector S - Air transportation

A. Discharges covered under this section. The requirements listed under this section apply to stormwater discharges associated with industrial activity from air transportation facilities including airports, airport terminal services, air transportation (scheduled and nonscheduled), flying fields, air courier services, and establishments engaged in operating and maintaining airports, and servicing, repairing or maintaining aircraft (generally classified under SIC Code 45), which have vehicle maintenance shops, material handling facilities, equipment cleaning operations, or airport or aircraft deicing or anti-icing operations. For the purpose of this section, the term "deicing" is defined as the process to remove frost, snow, or ice and "anti-icing" is the process which prevents the accumulation of frost, snow, or ice. Only those portions of the facility that are either involved in vehicle maintenance (including vehicle rehabilitation, mechanical repairs, painting, fueling, and lubrication), equipment cleaning operations, or deicing or anti-icing operations are addressed under this section.

B. Special definitions. The following definitions are only for this section of the general permit:

"Aircraft deicing fluid" or "ADF" means a fluid (other than hot water) applied to aircraft to remove or prevent any accumulation of snow or ice on the aircraft. This includes deicing and anti-icing fluids.

"Airfield pavement" means all paved surfaces on the airside of an airport.

"Airside" means the part of an airport directly involved in the arrival and departure of aircraft, including runways, taxiways, aprons, and ramps.

"Annual non-propeller aircraft departures" means the average number of commercial turbine-engine aircraft that are propelled by jet (i.e., turbojet or turbofan) that take off from an airport on an annual basis, as tabulated by the Federal Aviation Administration (FAA).

"Available ADF" means 75% of the normalized Type I aircraft deicing fluid and 10% of the normalized Type IV aircraft deicing fluid, excluding aircraft deicing fluids used for defrosting or deicing for safe taxiing.

"Collection requirement" means, for new sources, the requirement for permittee to collect available ADF.

"Defrosting" means the removal of frost contamination from an aircraft when there has been no active precipitation.

"Deicing" mean procedures and practices to remove or prevent any accumulation of snow or ice on:

1. An aircraft; or

2. Airfield pavement.

"Normalized Type I or Type IV aircraft deicing fluid" means ADF less any water added by the manufacturer or customer before ADF application.

"Primary airport" means an airport defined at 49 USC § 47102 (15).

C. Special conditions. Prohibition of nonstormwater discharges. In addition to the general nonstormwater prohibition in Part I B 1, the following discharges are not covered by this permit: aircraft, ground vehicle, runway and equipment washwaters, and dry weather discharges of deicing or anti-icing chemicals. These discharges must be covered by a separate VPDES permit. Note: Discharge resulting from snowmelt is not a dry weather discharge.

D. Stormwater pollution prevention plan requirements. SWPPPs developed for areas of the facility occupied by tenants of the airport shall be integrated with the plan for the entire airport. For the purposes of this permit, tenants of the airport facility include airline passenger or cargo companies, fixed based operators and other parties who have contracts with the airport authority to conduct business operations on airport property and whose operations result in stormwater discharges associated with industrial activity. In addition to the requirements of Part III, the SWPPP shall include, at a minimum, the following items.

1. Site description.

a. Site map. The site map shall identify the location of the following activities and indicate any of the activities that may be exposed to precipitation or surface runoff: aircraft and runway deicing or anti-icing operations; fueling stations; aircraft, ground vehicle and equipment maintenance and cleaning areas; and storage areas for aircraft, ground vehicles and equipment awaiting maintenance.

b. Summary of potential pollutant sources. The plan shall include a narrative description of the potential pollutant sources from the following activities: aircraft, runway, ground vehicle and equipment maintenance and cleaning; aircraft and runway deicing or anti-icing operations (including apron and centralized aircraft deicing or anti-icing stations, runways, taxiways, and ramps). Facilities which conduct deicing or anti-icing operations shall maintain a record of the types (including the safety data sheets (SDS)) and monthly quantities of deicing or anti-icing chemicals used, either as measured amounts, or in the absence of metering, as estimated amounts. This includes all deicing or anti-icing chemicals, not just glycols and urea (e.g., potassium acetate). Tenants and fixed-base operators who conduct deicing or anti-icing operations shall provide the above information to the airport authority for inclusion in the stormwater pollution prevention plan for the entire facility.

c. Deicing season. The SWPPP shall define the average seasonal timeframe (e.g., December-February, October-March, etc.) during which deicing activities typically occur at the facility. Implementation of control measures, including any BMPs, facility inspections, and effluent limitation monitoring shall be conducted with particular emphasis throughout the defined deicing season.

2. Stormwater controls.

a. Good housekeeping.

(1) Aircraft, ground vehicle and equipment maintenance areas. The permittee shall describe and implement measures that prevent or minimize the contamination of stormwater runoff from all areas used for aircraft, ground vehicle and equipment maintenance (including the maintenance conducted on the terminal apron and in dedicated hangars). Appropriate control measures (or their equivalents) shall be implemented, such as the following practices: performing maintenance activities indoors; maintaining an organized inventory of materials used in the maintenance areas; draining all parts of fluids prior to disposal; preventing the practice of hosing down the apron or hangar floor; using dry cleanup methods; and collecting the stormwater runoff from the maintenance area and providing treatment or recycling.

(2) Aircraft, ground vehicle and equipment cleaning areas. Permittees shall ensure that cleaning of equipment is conducted in designated areas only and clearly identify these areas on the ground and delineate them on the site map. The permittee shall describe and implement measures that prevent or minimize the contamination of the stormwater runoff from cleaning areas.

(3) Aircraft, ground vehicle and equipment storage areas. The storage of aircraft, ground vehicles and equipment awaiting maintenance shall be confined to designated areas (delineated on the site map). Appropriate control measures, including any BMPs (or their equivalents) shall be implemented, such as the following practices: indoor storage of aircraft and ground vehicles; the use of drip pans for the collection of fluid leaks; and perimeter drains, dikes or berms surrounding storage areas.

(4) Material storage areas. Storage vessels of all materials (e.g., used oils, hydraulic fluids, spent solvents, and waste aircraft fuel) shall be maintained in good condition, so as to prevent or minimize contamination of stormwater, and plainly labeled (e.g., "used oil," "Contaminated Jet A," etc.). The permittee shall describe and implement measures that prevent or minimize contamination of precipitation or runoff from storage areas. Appropriate control measures (or their equivalents) shall be implemented, such as the following practices: indoor storage of materials; centralized storage areas for waste materials; and installation of berms and dikes around storage areas.

(5) Airport fuel system and fueling areas. The permittee shall describe and implement measures that prevent or minimize the discharge of fuels to the storm sewer or surface waters resulting from fuel servicing activities or other operations conducted in support of the airport fuel system. Appropriate control measures (or their equivalents) shall be implemented, such as the following practices: implementing spill and overflow practices (e.g., placing absorptive materials beneath aircraft during fueling operations); using dry cleanup methods; and collecting the stormwater runoff.

b. Source reduction. The permittee shall minimize, and where practicable eliminate, the use of urea and glycol-based deicing or anti-icing chemicals in order to reduce the aggregate amount of deicing or anti-icing chemicals used and lessen the environmental impact. Chemical options to replace ethylene glycol, propylene glycol and urea include: potassium acetate; magnesium acetate; calcium acetate; anhydrous sodium acetate.

(1) Runway deicing operations. The permittee shall minimize contamination of stormwater runoff from runways as a result of deicing operations. The permittee shall evaluate present application rates to ensure against excessive over application by analyzing application rates and adjusting as necessary, consistent with considerations of flight safety. Appropriate control measures, (or their equivalents) shall be implemented, such as the following practices: metered application of chemicals; prewetting dry chemical constituents prior to application; installation of runway ice detection systems; implementing anti-icing operations as a preventive measure against ice buildup.

(2) Aircraft deicing operations. The permittee shall minimize contamination of stormwater runoff from aircraft deicing operations. The permittee shall determine whether excessive application of deicing chemicals occurs, and adjust as necessary, consistent with considerations of flight safety. This evaluation shall be carried out by the personnel most familiar with the particular aircraft and flight operations in question (versus an outside entity such as the airport authority). The use of alternative deicing or anti-icing agents as well as containment measures for all applied chemicals shall be considered. Appropriate control measures (or their equivalents) shall be implemented for reducing deicing fluid use, such as the following practices: forced-air deicing systems; computer-controlled fixed-gantry systems; infrared technology; hot water; varying glycol content to air temperature; enclosed-basket deicing trucks; mechanical methods; solar radiation; hangar storage; aircraft covers; and thermal blankets for MD-80s and DC-9s. The use of ice-detection systems and airport traffic flow strategies and departure slot allocation systems shall also be considered where practicable.

c. Management of runoff. Where deicing operations occur, the permittee shall implement a program to control or manage contaminated runoff to minimize the amount of pollutants being discharged from the site. The plan shall describe the controls used for collecting or containing contaminated melt water from collection areas used for disposal of contaminated snow. The following control measure options (or their equivalents) shall be considered: establishing a dedicated deicing facility with a runoff collection and recovery system; using vacuum or collection trucks; storing contaminated stormwater water or deicing fluids in tanks and releasing controlled amounts to a publicly owned treatment works; collecting contaminated runoff in a wet pond for biochemical decomposition (be aware of attracting wildlife that may prove hazardous to flight operations); and directing runoff into vegetative swales or other infiltration measures. The plan shall consider the recovery of deicing and anti-icing materials when these materials are applied during nonprecipitation events (e.g., covering storm sewer inlets, using booms, installing absorptive interceptors in the drains, etc.) to prevent these materials from later becoming a source of stormwater contamination. Used deicing fluid shall be recycled whenever possible.

d. Routine facility inspections. The inspection frequency shall be specified in the plan. At a minimum, inspections shall be conducted once per month during deicing and anti-icing season (e.g., October through April for most airports). If deicing occurs before or after this period, the inspections shall be expanded to include all months during which deicing chemicals may be used.

e. Comprehensive site compliance evaluation. The annual site compliance evaluations shall be conducted by qualified facility personnel during periods of actual deicing operations, if possible. If not practicable during active deicing or if the weather is too inclement, the evaluations shall be conducted when deicing operations are likely to occur and the materials and equipment for deicing are in place.

E. Numeric effluent limitations. The average deicing season identified in the SWPPP is the time frame during which any effluent limitation monitoring samples shall be obtained.

1. Airfield pavement deicing. Existing primary airports and primary airports meeting the definition of a new source (new primary airports ) with at least 1,000 annual jet departures (non-propeller aircraft) that discharge wastewater associated with airport pavement deicing comingled with stormwater shall either use deicing products that do not contain urea or alternatively, airfield pavement discharges at every discharge point shall achieve the numeric limitations for ammonia in Table 260-1, prior to any dilution or commingling with any non-deicing discharge. Primary airports that only use deicing products that do not contain urea shall certify this fact annually to the board. The certification shall be signed in accordance with Part II K, and a copy of the certification shall be kept with the SWPPP.

Table 260-1 Sector S – Numeric Effluent Limitations, Existing and New Primary Airports
Airfield Pavement Deicing
Parameter	Effluent Limitations - Daily Maximum
Ammonia as Nitrogen	14.7 mg/L

2. Aircraft deicing. Airports meeting the definition of a new source (new airports) with 10,000 annual departures, and located in cold climate zones, shall collect at least 60% of available ADF after deicing. New airports shall achieve the performance standards in Table 260-2 for available ADF collected. The limitation shall be met at the location where the effluent leaves the on-site treatment system utilized for meeting these requirements and before commingling with any non-deicing discharge.

Table 260-2 Sector S – Numeric Effluent Limitations, New Primary Airports
Aircraft Deicing
Parameter	Effluent Limitations
	Daily Maximum	Weekly Average
Chemical Oxygen Demand (COD)	271 mg/L	154 mg/L

3. Monitoring, reporting, and recordkeeping requirements.

a. Demonstrating compliance with the ADF collection requirement for dischargers subject to the requirements in subdivision 2 of this subsection.

(1) The permittee shall maintain records with the SWPPP to demonstrate that the airport is operating and maintaining one or more centralized deicing pads and shall certify this annually to the board. The certification shall be signed in accordance with Part II K, and a copy of the certification shall be kept with the SWPPP.

The centralized deicing pad technology shall be operated and maintained according to the technical specifications set forth in subdivisions 3 a (1) (a) through (d) of this subsection. The demonstration and valid certification are sufficient to meet the applicable collection requirement without the permittee having to determine the numeric percentage of available ADF collected.

(a) Each centralized deicing pad shall be sized and sited in accordance with all applicable Federal Aviation Administration advisory circulars.

(b) Drainage valves associated with the centralized deicing pad shall be activated before deicing activities commence to collect available ADF.

(c) The centralized deicing pad and associated collection equipment shall be installed and maintained per any applicable manufacturers' instructions and shall be inspected, at a minimum, at the beginning of each deicing season to ensure that the pad and associated equipment are in working condition.

(d) All aircraft deicing shall take place on a centralized deicing pad, with the exception of defrosting and deicing for safe taxiing.

(2) The permittee shall maintain records with the SWPPP on the volume of ADF sprayed and the amount of available ADF collected in order to determine compliance with the collection requirement and shall report this information annually to the department.

b. Monitoring requirements.

(1) COD limitation. Permittees subject to the ADF collection and discharge requirements specified in subdivision 2 of this subsection shall conduct effluent monitoring to demonstrate compliance with the COD limitation for all ADF that is collected.

Compliance shall be demonstrated at the location where the effluent leaves the on-site treatment system utilized for meeting these requirements and before commingling with any non-deicing discharge. Effluent samples shall be collected following the grab sample protocol in 40 CFR 449, Appendix A.

(2) Ammonia limitation. If a permittee chooses to comply with the compliance alternative specified in subdivision 1 of this subsection, the permittee shall conduct effluent monitoring at all locations where pavement deicing with a product that contains urea is occurring, prior to any dilution or commingling with any non-deicing discharge.

c. Recordkeeping.

(1) The permittee shall maintain records with the SWPPP documenting compliance with subdivisions 3 a and 3 b of this subsection. These records include, but are not limited to, documentation of wastewater samples collected and analyzed, certifications, and equipment maintenance schedules and agreements.

(2) The permittee shall collect and maintain data with the SWPPP on the annual volume of ADF used.

F. Benchmark monitoring and reporting requirements. Stormwater discharges from those portions of air transportation facilities where vehicle maintenance (including vehicle rehabilitation, mechanical repairs, painting, fueling, and lubrication) and equipment cleaning is performed shall be sampled for the parameters listed in Table 260-3. Note: The benchmark monitoring requirements apply year round and are not limited to the deicing season.

Table 260-3 Sector S – Benchmark Monitoring Requirements
Pollutants of Concern	Benchmark Concentration
Air Transportation Facilities (SIC 45).
Total Suspended Solids (TSS)	100 mg/L
Total Petroleum Hydrocarbons (TPH)*	15.0 mg/L
*Total Petroleum Hydrocarbons (TPH) is the sum of individual gasoline range organics and diesel range organics (TPH-GRO and TPH-DRO) to be measured by EPA SW 846 Method 8015 for gasoline and diesel range organics, or by EPA SW 846 Methods 8260 Extended and 8270 Extended.

Historical Notes

Derived from Volume 15, Issue 09, eff. June 30, 1999; amended, Virginia Register Volume 20, Issue 16, eff. July 1, 2004; Volume 25, Issue 19, eff. June 24, 2009; Volume 30, Issue 11, eff. July 1, 2014.

Statutory Authority

§ 62.1-44.15 of the Code of Virginia; § 402 of the federal Clean Water Act; 40 CFR Parts 122, 123, and 124.