Small Airports, Big Challenges

There are more than 19,000 aviation facilities in the United States and its territories, based on the Federal Aviation Administration’s (FAA’s) 2012 Report to Congress: National Plan of Integrated Airport Systems (NPIAS) 2013–2017 and the FAA’s 2012 report on General Aviation. These facilities include more than 13,400 airports and 5,500 heliports, as well as smaller numbers of other types of aviation facilities. The vast majority of these aviation facilities (more than 14,500) are private-use facilities, leaving just over 5,000 publicly accessible facilities. The type of public airport people are most familiar with (such as Los Angeles or Chicago O’Hare International Airports) in fact represents a very small fraction of the total. These principal airports, categorized as “primary airports” by FAA, each provide scheduled commercial service for more than 10,000 passenger enplanements (boardings) per year, but account for only 378 of the airports in the US and its territories (FAA 2012, FAA 2012a).

Credit: GZA GeoEnvironmental
Plane fueling

Instead, the majority of airports in the US offer limited or no commercial service, but provide other vital transportation functions. According to FAA (2012a), of the abovementioned 19,000+ aviation facilities, “3,330 are included in the FAA’s National Plan of Integrated Airport Systems, are open to the public, and are eligible for Federal funding via the Airport Improvement Program (AIP).” These 3,330 airports include the 378 primary airports, with the remainder—nearly 3,000 facilities—ordinarily referred to as “general aviation airports,” the largest single category of airport facilities. General aviation airports serve vital functions, including air cargo, corporate service, private flights, aerial survey/observation, flight instruction, medical flights, agriculture, emergency response, and access to remote areas (FAA 2012).

General Aviation Versus Its Larger Counterparts
General aviation airports often differ significantly from primary airports in size, function, funding, and operations, but are regulated in much the same manner under EPA’s National Pollutant Discharge Elimination System (NPDES) Multi-Sector General Permit (MSGP) for Stormwater Discharges Associated With Industrial Activity (herein referred to as the MSGP). Currently, 46 states and the US Virgin Islands are “delegated states” authorized by EPA to issue their own NPDES permits. Four states, the District of Columbia, Puerto Rico, most US territories and Indian lands, and federal operators and oil and gas operations in a few states are non-delegated and still fall under the federal permit. This discussion focuses on general aviation airports in non-delegated states and the unique challenges they face in complying with the MSGP, using insight gained from work conducted at public, AIP-eligible, general aviation airports located in New England.

General aviation airports have fewer enplanements than their primary airport counterparts and typically conduct fewer deicing and fueling operations. Deicing at general aviation airports is often conducted less by chemical means and more through the use of heaters and interior storage of aircraft. Chemical deicing is expensive and typically reserved for charters, executive aircraft, or commercial service. The MSGP acknowledges this by limiting benchmark water-quality monitoring to those airports with a threshold minimum level of annual deicing chemical use. The MSGP also specifies requirements for those airports that deice pavements and limits requirements for deicing agent collection to airports with a certain number of annual departures.

The majority of the remainder of MSGP requirements for Sector S-Air Transportation applies to all airports, regardless of size, operations, or financial status. For example, fuel storage is generally the largest material storage at any airport, but fuel is stored in significantly different quantities at primary airports as compared to general aviation airports. At Boston Logan International Airport, over 7 million gallons of fuel is stored onsite (Infanger 2000). In contrast, a regional general airport in the area may store less than 100,000 gallons, and a smaller general aviation airport in the area may store only 10,000 gallons. Clearly, the risks associated with the storage, delivery, and fueling activities at these three types of airports would be very different. This raises the question of whether MSGP requirements should be variable to better consider the risks inherent with differing levels of industrial activity.

Historical Approach to Stormwater Management
Airports in the US have a long history, with many dating to the World War II era, and some to the earliest days of aviation. In most cases, original airfield construction and subsequent airport improvements occurred prior to the development of the NPDES stormwater permit programs or other state and local regulations related to stormwater runoff. Stormwater systems at these airports have often been installed and modified over time, in conjunction with development and in response to localized flooding issues. Similarly to highways and roadways, stormwater management at airports historically focused on removing stormwater runoff quickly from runways, taxiways, and aprons to maintain safety and operations, largely without consideration for potential water-quality impacts. This focus on rapid removal of runoff has frequently led to the construction of complex drainage systems along runways, taxiways, and aprons, with numerous stormwater outfalls spread across facilities. In many cases, these stormwater outfalls were constructed in or near regulated wetland resource areas or, due to the quantity of runoff, in areas that could eventually develop into wetland resource areas.

General Aviation Considerations
While historical approaches to stormwater management may have been similar for highways and for runways and taxiways at general aviation airports, the pollutant potential for runoff from these surfaces is actually quite different. While highways and roadways are typically deiced or sanded, runways and taxiways are not subject to these practices at many general aviation airports, lessening pollutant potential. In addition, there are significant safety concerns related to debris or particulates on runways and taxiways, which require monitoring for and removal of such particles, again lessening the pollutant runoff potential. Coordination with EPA on the issue of activities conducted on runways and taxiways and the associated pollution potential led to guidance from the agency indicating that runways and taxiways could be excluded as regulated industrial activity areas under the MSGP for airports as long as these areas are not used for industrial activities specified by the MSGP (fueling, maintenance, cleaning, storage, or deicing practices). In fact, industrial activity areas at general aviation airports may be only a small portion of the total site area, because airport properties are often several hundred acres in size with large expanses of grassed areas and areas dedicated to runway/taxiway pavements and safety areas, while areas subject to the MSGP may be limited to areas with hangars, fuel farms, apron pavements, and other support buildings because those are where fueling, maintenance, cleaning, storage, and deicing activities generally take place.

Due to federal safety requirements, development at airports is limited to specific areas and distributed within the property based on theoretical height and distance separations from runways, taxiways, and approaches. These safety requirements dictate where development can be located and limit the ability to centralize all industrial activity areas in one place onsite. Similarly, for safety reasons, some activities and large-scale material storage (such as fuel farms, fueling stations, and mobile refueling) need to occur outdoors, exposed to precipitation.

Some activities occur outdoors simply for financial reasons. For example, aircraft at a general aviation airport may be stored outdoors, either because they are not permanently based at that airport, or because of hangar space limitations or financial limitations. As a result, basic mechanical checks and maintenance for these aircraft may need to occur outdoors, exposed to precipitation. These factors can increase the extent of an airport’s regulated industrial activity areas and often increase the regulatory burden for inspections and monitoring.

Due to the piecemeal installation of drainage over time, the presence of stormwater systems that predate permitting considerations, and safety requirements that dictate the location of and often force the decentralization of industrial activity areas, MSGP-regulated stormwater runoff is often comingled with runoff from non-industrial areas, adding to the regulatory burden of inspections and monitoring by subjecting larger areas of the site to regulation under the MSGP.

Credit: GZA GeoEnvironmental

The Challenge of Drainage System Separation
Physically separating comingled (industrial and non-industrial) stormwater drainage systems into industrial and non-industrial areas would reduce this burden, but can be a complex process, requiring capital improvement funding, permitting, water-quality retrofits, and construction within active airfields. Having separate stormwater drainage systems for industrial and non-industrial areas is beneficial, allowing for structural best management practices (BMPs) targeted at industrial pollutants to be installed in fewer locations, reducing capital expenditures and often extending the BMPs’ functional life. Simpler drainage systems also allow for better spill response, as compared to lengthy, complex systems with comingled drainage areas. Separating the systems also would potentially allow for reducing the number of industrial stormwater outfalls, thereby reducing areas subject to inspections and outfalls subject to MSGP monitoring and assessment requirements.

Although there are significant benefits to separating the drainage from industrial and non-industrial activity areas, there are also significant challenges. Due to the age of some airports and the complexity of drainage systems, separating systems may not be as easy as capping a few pipes and installing a new outfall. The project may require work in active areas of the airfield and could even require runway or taxiway closures or closure of a portion of an apron, activities that have significant operational and financial impacts for the airport.

Another challenge for such projects is the required capital expenditure. General aviation airports usually do not have the same level of financial support or success that comes from being a commercial service airport, and instead operate on private or municipal funding and income from aviation lease agreements, often coupled with grants and support from federal and state agencies (FAA 2012a). Primary and commercial airports have revenue streams that general aviation airports typically do not have, such as revenue from rental car companies, in-terminal concessions, parking fees, passenger facility charges, and advertising programs (Transportation Research Board 2007). As a result, general aviation airports often struggle for financial solvency and depend on grants and subsidies (FAA 2012a). Many general aviation airports turn to non-aviation businesses or to the construction of an airport business park to provide supplemental means of financial support.

For many general aviation airports, financial limitations could prevent the work, unless it can be funded as part of a project scheduled to be undertaken with state or federal grant monies. If that is the case, time will be needed to prepare planning documents; secure funding; design the improvements; obtain the necessary local, state, and federal permits and approvals; and go to construction. Within typical timelines at general aviation airports, this process could take several years, potentially pushing into the next MSGP permit cycle, by which point requirements could change again.

Experience with New England airports has shown that permitting airport improvement projects can be a major challenge. Many airports have regulated wetlands or rare species that can dictate the permitting process, design, and mitigation, including stormwater design requirements. Redirecting runoff from one area of an airport to another could also potentially change the drainage basin to which the area discharges, which could further complicate permits if the basin or water body to which the discharge is redirected is impaired or has an assigned total maximum daily load. All of these factors add layers of complexity to a project that once seemed simple, impacting costs, timeline, and future permitting and operations onsite.

Operational Issues and the Link to Compliance
Beyond the challenges presented by an airport’s age, stormwater systems, layouts, and funding and permitting obstacles, MSGP compliance challenges are also linked to ongoing airport operations. Through extensive work over a more-than-10-year period at general aviation airports in New England related to stormwater permit compliance, it has become apparent that specific compliance-related issues are prevalent and can be categorized into three main areas:

  • Lack of resources (financial and personnel)
  • Lack of knowledge of regulations, including lack of education on how to comply
  • Issues related to the age, size, and complexity of the facility (e.g., material storage, inspections)

General aviation airports often have limited staff, sometimes as little as an airport manager with no support staff or with seasonal staff that turn over often. Staff members are responsible for the operation and upkeep of potentially several hundred acres, and they perform a diverse range of activities such as mowing, snow removal, wildlife management, fueling, safety reviews, and potentially administrative and financial duties. Budgets are limited, as previously discussed, which dictates staffing levels, purchases, and maintenance activities onsite. Because revenue for general aviation airports is typically tied to fuel sales, commercial leases, hangar leases, agricultural leases, and landing/ramp fees (Briggs 2012), staff often focus on servicing these areas that are critical to financially supporting the facility. Adding on permitting requirements can be a daunting task for these staff, whether it be for the MSGP, fuel storage, or environmental permits. Time required for inspections, monitoring, and maintenance of BMPs is often seen as time away from their “real” duties, which are necessary to continue airport operations. MSGP compliance tasks and recordkeeping may seem relatively unimportant to general aviation management, as compared to daily activities required to keep the airport in business and to maintain safety.

There is often a lack of education or knowledge of the MSGP, even though the initial stormwater permit cycle has passed. An education process is needed in many cases to help staff, as well as individual tenants and pilots, understand the MSGP, its requirements, and the implications for the airport if the permit is not followed and enforcement actions result. Permit compliance requires buy-in from all those conducting activities at the airport, since each person has a role and a stake in helping to comply, starting with activities such as good housekeeping and materials management.

Staff may find the complexity of the permit to be difficult on top of all the other documents they need to maintain and may request consultant assistance with summarizing the permit into components, with checklists, bullets, and easy-to-understand, condensed instructions of what needs to be done and how often. Creating these lists presents the airport with a clear-cut “task chart” of what needs to happen daily, weekly, periodically, or annually, as well as understanding event-based tasks associated with fueling and deicing. This identification of tasks can cause stress by presenting new tasks that need to be completed but also often shows an airport that it is already completing many of the necessary tasks as part of its regular operations. Creating blank inspection forms to be used for each routine inspection can also help to better direct the process and make it proceed more efficiently.

The age, size, and complexity of general aviation airports can also create issues for compliance. A single airport might have 20 or more individual hangars (each of which may have multiple tenants), as well as a snow removal equipment building, terminal, fixed base operators, and maintenance shops, as well as non-aviation businesses, all simultaneously operating at the facility under various lease and ownership agreements. Some structures may date to the 1940s or earlier and may have housed the same tenant for decades. Long-term tenants may be storing large quantities of materials, or materials of a diverse nature, that they have acquired over time and are reluctant to discard. They may not have secondary containment in place, or may not be aware of how to safely store chemicals that are not compatible. Ideally, such materials are stored indoors, but in some cases they may not be, increasing the airport’s potential liability and non-compliance risk.

Credit: GZA GeoEnvironmental
Fuel storage tanks

Each airport needs to understand its tenant agreements and make determinations as to who is responsible for the various requirements of the airport’s MSGP permit. Who will perform inspections at the airport’s operations? Who will conduct inspections at tenant operations? How will all parties be educated, and how will the facility-wide information be tracked? For an airport facility that may have 50 or more operations and tenants onsite, managing and coordinating inspections, education programs, and recordkeeping can be an onerous task. Airport staff may exhibit a “hands-off” attitude when it comes to inspecting tenants’ rental hangars, not wanting to irritate tenants who are a critical part of the airport’s revenue stream; thus, they can be unaware of the activities or material storage practices that take place. Overall, developing unified practices for all tenants and airport operations, making all parties aware of the regulations and aware of their responsibilities, maintaining records, and providing enforcement can be a difficult and time consuming process for an airport manager.

Conclusions and Lessons Learned
Overall, lessons can be learned by aviation managers and consultants, environmental consultants, regulators, and the aviation community at large. Takeaways from this may extend beyond the aviation industry and can be applied to other industries in their ongoing efforts toward permit compliance.

For MSGP compliance by the general aviation community, simple education and training programs are key activities to promote compliance by facilities with limited resources and understanding of lengthy and complex permit requirements. General aviation airports rely on low levels of staffing with significant turnover to implement and maintain programs, including those for permit compliance. Staff focus on efforts such as mowing, snowplowing, and maintenance/upkeep. For permit compliance to come to the forefront, education is important, as well as teaching staff how to document activities that they are already doing for permit compliance. Laminated checklists and maps that can be posted in vehicles and equipment can provide visual, easy-to-understand reminders of tasks that need to be completed. Consultants have the role of developing and updating plans, but must also provide the role of educator to keep facilities informed of regulatory changes and the implications.

From a capital improvements standpoint, work at airports is heavily driven by funding from the FAA and state transportation agencies. Environmental consultants need to work with aviation consultants to help them understand changing regulations and requirements associated with the MSGP, particularly when compliance with the MSGP requires or can be facilitated by capital improvements to drainage systems, material storage, or new construction. Aviation consultants need to plan ahead to incorporate drainage separation projects and necessary BMPs into larger capital improvement projects and to pursue funding for MSGP and pollution prevention compliance. By working together, environmental and aviation consultants can coordinate with airport management to provide temporary solutions and BMPs until more permanent solutions can be funded and constructed.

Finally, funding agencies (FAA, state transportation agencies, etc.) should look at the changing requirements faced by airports and consider how to provide airports with compliance assistance. Assistance could be in the form of training, education, facilitating new ways of funding projects and improvements to aid MSGP compliance, or providing staff to directly assist with inspections and audits to help keep airports on track. These agencies should also be aware of proposed changes to permits and advocate for airports. Educating regulators on the challenges faced by different sectors of those covered by the MSGP and different classes of industry within each sector (e.g., primary airports versus general aviation airports) could help tailor permits and make them more efficient and effective, while reducing more laborious requirements for those types of businesses with fewer resources. Finally, aviation advocacy associations, such as the Aircraft Owners and Pilots Association (AOPA) and the American Association of Airport Executives (AAAE), can also help by facilitating education and training assistance for general aviation and keeping abreast of proposed regulatory changes to lobby on behalf of aviation for simpler, more streamlined requirements.

The combination of these actions can support an industry that is a critical component of our transportation network and can at the same time support the water-quality protection that is the ultimate goal of the MSGP.

References

Briggs, Joelle. 2012. How Airports Make Money and What’s New in Compliance—Presentation to the Northwest Mountain Region Airports Conference.

Federal Aviation Administration (FAA). 2012. General Aviation Airports: A National Asset. A Fresh Look at the Many Roles General Aviation Airports Play in the National Air Transportation System.

FAA. 2012a. Report to Congress: National Plan of Integrated  Airport Systems (NPIAS) 2013–2017. Report of the Secretary of Transportation to the United States Congress Pursuant to Title 49 U.S. Code, Section 47103.

Infanger, John F. 2000. “Consolidating Fuel Delivery at Logan,” Aviation Pros. Available online at www.aviationpros.com.

Transportation Research Board. 2007. Airport Cooperative Research Program (ACRP) Synthesis 1—Innovative Finance and Alternative Sources of Revenue for Airports: A Synthesis of Airport Practice.

US Environmental Protection Agency (EPA). 2008. NPDES MSGP for Stormwater Discharges from Industrial Activity. (As modified).

About the Author

Jennifer R. M. Burke and Thomas E. Jenkins

Jennifer R. M. Burke, P.E., CPSWQ, LEED Green Associate, and Thomas E. Jenkins, P.E., are with GZA GeoEnvironmental, Inc. in Springfield, MA.