Environmental engineering intersects both the structure and function of environmental systems (natural and human-made) and the myriad issues that arise from human intervention in those systems. Traditionally, environmental engineers have dealt with problems such as the management of pond and stream quality, contamination from industrial or agricultural waste, fish kills, and the development of effective mitigation strategies for air, soil, and water pollution, to name some. For environmental engineers, these problems are not just technically complex, but also must take into account the social demand for the resources involved, as well as zoning, regulatory, and legal constraints.