Owners of residential property located near, and at risk from, a source of contamination, like owners of property that has actually been contaminated, often find it difficult, if not impossible, to sell their property and usually cannot sell it at a fair market price. From the point of view of prospective buyers, both kinds of property, whether actually contaminated or at risk of contamination, are undesirable. Owners of both types of property witness a decline in their property value and suffer the stress and anxiety that naturally accompanies injury to one's most significant economic asset.

Owners of both kinds of property share three concerns: Will their property or families be exposed to the contamination; will the industrial facility from which the contamination migrated be the source of additional contamination; and will the presence of the contamination change the character of the neighborhood? If any of these questions can be answered in the affirmative or cannot yet be answered, the value of all property in the neighborhood, contaminated and uncontaminated alike, is likely to decline.