Areas that once housed industrial or commercial activities and now contain potentially hazardous substances or pollutants are significant features in urban landscapes. These sites often require remediation before redevelopment can occur. An example would be an abandoned factory site with soil contamination.
The re-purposing of such locations is crucial for sustainable urban development. It reduces urban sprawl, minimizes pressure on greenfield sites, and promotes environmental justice by revitalizing neglected neighborhoods. Historically, these locations have presented both challenges and opportunities for urban planners seeking to maximize land use and mitigate environmental risks.