Types and Causes

Land contamination, whether intended, accidental, or naturally occurring activities and events, come from a large variety of sources, such as manufacturing (chemicals, commercial products), disposal and transportation, mining (minerals, coal, uranium), natural disasters (hurricanes, floods), agriculture (pesticides, fertilizers), waste management (landfills), energy production (radioactive), national defense activities, and elements that occur naturally (lead, arsenic).

Nationally, there are thousands of contaminated sites of varying size and significance.

Effects

Contaminated lands can pose a variety of health and environmental hazards. Some contaminated sites pose little risk to human health and the environment because the level of contamination is low or the chance of exposure to toxics is also low.

Other contaminated sites can pose greater risks to human health and the environment because the chemicals at these sites may exist in the environment for long periods of time or move easily through the environment. These sites must be carefully managed through containment, institutional controls such as access restriction, and/or cleanup to prevent harm to humans, wildlife, or the surrounding environment both on- and offsite.