GREENFIELDS, BROWNFIELDS, GRAYFIELDS, AND BLACKFIELDSGreenfields are properties that have experienced little or no impact from humandevelopment activities. Greenfields can also be defined to include agriculturalland that has had no activity other than farming. Like recycling in general,recycling of land is an important objective in creating high-performance greenbuildings. Land recycling refers to reusing land impacted by human activitiesinstead of using greenfields. There are at least three identifiable categories ofpotentially recyclable land: brownfields, grayfields, and blackfields.The US Environmental Protection Agency (EPA) defines brownfields asabandoned, idled, or underused industrial and commercial facilities whereexpansion or redevelopment is complicated by real or perceived environmentalcontamination.4 The official definition of a brownfield site, according to PublicLaw 107-118 (H.R. 2869), the Small Business Liability Relief and BrownfieldsRevitalization Act, signed into law January 11, 2002, is as follows: “With certain legal exclusions and additions, the term ‘brownfield site’ means realproperty, the expansion, redevelopment, or reuse of which may be complicatedby the presence or potential presence of a hazardous substance, pollutant, orcontaminant.” The key word in the first definition is perceived; the key phrase inthe second is potential presence. Former industrial properties are often thoughtto be contaminated because of the activities that occurred on the site—forexample, metal plating or leather tanning. In fact, not infrequently theseproperties are fairly clean, requiring minimal cleanup. In many US cities,brownfields are now valuable real estate because of their proximity to extensiveinfrastructure and a potential workforce. Industries formerly fleeing to green-fields outside urban areas, thereby causing impoverishment of minority communities due to job loss, are returning to former industrial sites because theeconomics dictate the return to the city. A prime example of the potentialsuccess of a well-developed brownfields strategy is the Chicago BrownfieldsInitiative, which since 1993 has been assisting in the cleanup and transfer of 12major former industrial sites in the city. An interesting aspect of the Chicagostrategy has been to emphasize the return of these zones to industrial use, thusbringing jobs back into the city
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