Environmental contamination can mean a variety of things. Often, it occurs when there are levels of contaminants present in the soil and/or groundwater of a property. These contaminants may be oils or petroleum-based products, chemicals, metals or other organic or inorganic materials that are present at levels higher than what would normally be expected. Contamination may result from historical activities on or near the property or a spill on or near the property. Environmental contamination may also refer to the condition of a structure or building, such as the presence of mould.