How does contamination of surface and groundwater typically occur at airports?

Contamination of surface and groundwater at airports primarily occurs through runoff that leaches pollutants from various products or waste. Airports often use de-icing chemicals, fuel, oils, and other substances that, when it rains or when snow melts, wash off surfaces such as runways, taxiways, and parking areas. This runoff can carry the harmful contaminants into nearby water bodies, leading to significant environmental impact.

The process of leaching is especially concerning because it involves not just the transport of pollutants but also the potential for these harmful substances to infiltrate the soil and reach groundwater supplies. Over time, this can result in the accumulation of toxic compounds in water sources, affecting both ecosystems and human health.

Other methods of contamination, such as direct dumping of waste or spills during fueling operations, can certainly contribute to localized pollution incidents but are not as widespread or systemic as the runoff issue. Vapor emissions also pose a risk, but their impact on water contamination is less direct compared to runoff. Thus, the leaching of pollutants due to runoff is the most significant pathway for surface and groundwater contamination at airports.