As the more significant environmental impacts of deicing activities are mitigated by runoff controls, increasing scrutiny is being directed toward other issues, including the occurrence of microbial slime at stormwater outfalls. The challenge to the aviation community for addressing this issue is significant, because microbial growth associated with deicing discharges is not currently predictable, the controlling factors are poorly understood, and the costs of treatment controls are substantial. For example, “sewer bacteria” such as Sphaerotilus natans (a filamentous bacterium associated with organic-rich wastewater discharges), appear to be ubiquitous in the environment, and may flourish wherever the right conditions exist. This situation presents a high level of risk associated with the large investments needed for controls that may or may not eliminate the microbial growths. Airports need reliable information on what is and is not known about the factors contributing to the occurrence of nuisance microbes and the options for controlling them. Environmental regulators would also benefit from this information as they consider potential requirements.
The objectives of this research are to: (1) provide airports and regulatory agencies with a reference document that summarizes what is currently known and not known about the occurrence of nuisance microbial communities in receiving waters in the vicinity of airports; (2) identify the interrelationships among the environmental parameters controlling their growth; and (3) produce a detailed work plan listing the steps needed to address knowledge gaps and to prepare a guidebook providing practical mitigation alternatives for managing nuisance microbial communities.
Research is complete. The results are available in ACRP Report 115.