Having spent some years doing housing development in the UK, this was an everday, common or garden term, simply used in opposition to greenfield. The previous development could have been housing, community use buildings, industrial, hospital sites etc. and did not necessarily involve pollution, though one always checked rather more than with greenfield sites (one needs to check greenfield sites for possible sources of pollution as well). A polluted greenfield site, does not get reclassified as a brownfield site.

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UK government policy, especially since the 1990s has encouraged brownfield site development to control urban sprawl, protect farmland and natural sites and to reduce derelict sites. Extra costs of brownfield development include the higher incidence of contamination to be remediated, but also include land prices, site access problems, demolition of existing structures, smaller economies of scale, boundary issues etc.

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NB. As the term "brownfield" has specific meaning in UK planning law, it is worth noting that this meaning is subject to change with legislation, as with the recent change excluding gardens (previously classified as brownfield).

"28 Feb 2011 - Planning Law Reform. 16. Stephen Phillips .... The Government have already changed the definition of brownfield sites to exclude gardens ... "
http://www.publications.parliament.uk/pa/cm201011/cmhansrd/c...

"Brownfield and greenfield land

Previously developed land or brownfield land is land that is, or was, previously occupied by a permanent structure (excluding agricultural or forestry buildings) and associated fixed surface infrastructure.

The definition also covers the curtilage of the development, that is the area of land attached to a building - including gardens. For a detailed definition see Planning policy guidance 3 - housing.

Greenfield land

Greenfield land is land that has never been built on or where the remains of any structure or activity have blended into the landscape over time. Greenfield land should not be confused with green belt land. Green belt is a term for land around cities and large built-up areas left permanently open or largely undeveloped.

The government target is that by 2008, 60% of additional housing in England should be provided in previously developed land (brownfield land) or by re-using existing buildings. It is expected that at least 99% of housing completions in Wolverhampton in future years will be on previously developed land."
http://www.wolverhampton.gov.uk/environment/land_premises/br...


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