Brownfields

Brownfield land is an Anglo-American term used in urban planning to describe land previously used for industrial or commercial purposes with known or suspected pollution including soil contamination due to hazardous waste. Land that is more severely contaminated and has high concentrations of hazardous waste or pollution, such as a Superfund site, does not fall under the brownfield classification. After clean up, such an area can become a community park or business development.

Environment Canada defines brownfields as "abandoned, idle or underutilized commercial or industrial properties [typically located in urban areas] where past actions have caused environmental contamination, but which still have potential for redevelopment or other economic opportunities."

The term brownfields first came into use on June 28, 1992, at a U.S. congressional field hearing hosted by the Northeast Midwest Congressional Coalition. Also in 1992, the first detailed policy analysis of the issue was convened by the Cuyahoga County Planning Commission. The United States Environmental Protection Agency selected Cuyahoga County as its first brownfield pilot project in September 1993. The term applies more generally to previously used land or to sections of industrial or commercial facilities that are to be upgraded.

Brownfield land is an area of land previously used or built upon, as opposed to greenfield land, which has never been built upon. It is a term used in urban planning to describe land within certain legal exclusions and additions, which was previously used for industrial or commercial purposes, where its expansion, redevelopment or reuse may be complicated by the presence or potential presence of a hazardous substance, pollutant or contaminant.

Land that is more severely contaminated and has high concentrations of hazardous waste or pollution, such as a Superfund site, does not fall under the brownfield classification.Mothballed brownfields are properties that the owners are not willing to transfer or put to productive reuse.

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Wikipedia