Shift in Priorities
Emerging technologies will impact tomorrow's airport environment. For now, fuel systems are still a big focus
BY Sarah Smith, President, Madison Environmental
June 1999
There is bad news and good news on the horizon regarding environmental compliance issues at airports. The bad news is that it is the general consensus that regulations affecting noise, air and water quality, and fuel systems will continue to evolve, which historically results in locally unrealistic standards. Although the trend certainly appears to include risk-based decisionmaking, we most likely have not seen the peak of restrictive regulations.
The good news is that technologies are rapidly evolving on numerous fronts to enable planning, compliance, and monitoring at a fraction of the current costs. Developments in the reduction of air and water contaminants (both in the generation/operations and treatment areas) will continue to make it easier and, eventually, cheaper to comply with federal, state, and local regulations. The potential market for technologies that reduce and mitigate air emissions, noise, petroleum, and deicing releases is so large that a race is underway for new products and services. The industry will ultimately benefit from this technology race.
Technology and Information Processing
The continued development of computer capabilities, geographic information
systems (GIS), global positioning systems (GPS), remote sensing (e.g.
radar and hyperspectral imaging), and physical/chemical sensors will increase
the quality of environmental planning and assessment and dramatically
decrease the costs. As the ability to process large amounts of information
becomes faster, new technologies that take advantage of processing speeds
will be developed.
Today, the capability to use digital maps and photographs within a GIS and link databases to the GIS are increasing the efficiency and quality of environmental assessments. The use of GPS to collect field data is reducing costs associated with environmental studies and cleanup. Sensors which can detect changes in the physical parameters of air (i.e., Conformity Rule of the Clean Air Act related to construction/expansion projects), noise, and storm/groundwater are being used to collect environmental data on a continuous basis. By connecting the sensors with computers via telecommunications, massive amounts of information can be collected and processed at a fraction of historic costs.
ASTs, hydrant lines
Now that we are through the big push to achieve compliance with the underground
storage tank (USTs) regulations, the focus has shifted to aboveground
storage tanks (ASTs) and hydrant lines. Hydrant systems are widely used
at large airports to transport fuel from large storage tanks to hydrant
pits on the aircraft ramp where hydrant trucks can deliver the fuel directly
into aircraft. This has proven to be a very efficient way to move large
quantities of fuel from storage directly into aircraft without trucking
fuel from the fuel farm to the aircraft ramp. Large airports may load
over a billion gallons of jet fuel per year into aircraft via a complex
hydrant system.
Initially, hydrant systems were installed as single-wall piping systems relying on continuous inventory management and regular hydrostatic testing to confirm that the systems were leak tight. In the 1980s double-wall piping with interstitial monitoring was developed for fuel underground storage tanks (USTs) typically at service stations, to meet regulatory requirements related to the 12/22/98 UST compliance deadline. This technology appeared to be appropriate for use on airport hydrant lines, and a number of double-wall airport hydrant systems were installed during the 1980s. Typically these systems have suffered a myriad of problems including frequent false alarms and local corrosion of the primary steel carrier pipe. The industry has since moved away from double wall airport hydrant systems due to extremely high initial cost and repeated false alarms caused by equipment malfunction, water condensation in the interstitial space, and problems related to inadequate cathodic protection of the carrier pipe.
Until approximately five years ago, the accepted method of hydrant system leak detection on airport hydrant systems was perpetual inventory management and nightly hydrostatic tests of the piping system by observing pressure changes in the system during periods of non-operation. Until recently the accuracy of these leak detection methods had not been defined, nor was it scrutinized by regulatory authorities.
Since that time, state regulatory authorities have focused on airport hydrant system leak detection resulting in past methods of leak detection (perpetual inventory management and nighttime hydrostatic leak testing) not having the inherent accuracy required to prevent environmental problems related to hydrant line leak detection. California and Virginia recently promulgated regulations requiring that airport hydrant lines be tested with a leak detection accuracy of 3 to 5 gph.
Several airports have undergone the design, permitting, and construction of a centralized bulk storage facility for the entire airport and required tenants to remove their old fuel systems. Others are in the planning or evaluation phase on how best to deal with the old fuel system (e.g. upgrade or replace).
One issue is when and how to test the hydrant system and, if found to be leaking, how to approach the situation (e.g. abandon the line, replace with new, or repair). Most of the older hydrant lines, hydrant pits, and transfer lines were not installed with a leak detection system, or had secondary containment (double-wall pipe) or corrosion protection.
A Need for Internal Documentation
Most airport fuel systems are reaching 20 and 30 years of services or
more and are starting to show signs of deterioration. Once the old system
is tagged with abandonment, the next issue is how to handle the environmental
impact. Although environmental-related projects are not cheap, the government
is allowing the approach to soil and groundwater clean-up to be evaluated
on level of risk to the environment and surrounding receptors (populations,
schools, water supply wells, etc.) versus cleaning up every drop of fuel
at an airport.
Many airports and tenants have constructed new fuel systems to replace the old. Although not required by the regulations, owners and operators of new fuel systems should consider creating a document which describes the system in detail and the operation and maintenance procedures of the system.
Some of the newer systems include equipment that is unfamiliar to most (e.g., automatic leak detection for hydrant lines) and the manufacturer's manual may be difficult to interpret. Creating a manual which describes how to operate the system from top to bottom and procedures to follow in the event something goes wrong would minimize risk associated with operating the farm and maximize the operation of the facility.
Over the past five to ten years, tenants and airports alike have identified their issues and liabilities and, in most cases, either fixed the problem or have plans in place to do so. The environmental program for most has become one of maintaining versus reacting which is a result of the UST compliance deadline and general awareness of the regulations which apply to airports.