Hội Mỹ cho thử nghiệm và Vật liệu (ASTM) định nghĩa brownfields như Cơ quan bảo vệ môi trường Mỹ (EPA) "bị bỏ rơi, đã bỏ không, hoặc sử dụng đúng mức tài sản mà mở rộng hoặc tái phát triển là phức tạp bởi sự tồn tại tiềm năng hoặc đã xác định hóa chất (s) quan tâm." trang web, "Brownfields bị từ bỏ, đã bỏ không, hoặc sử dụng cơ sở công nghiệp và thương mại nơi mở rộng hoặc tái phát triển là phức tạp bởi ô nhiễm môi trường hoặc nhận thức." giữa thế kỷ thứ. | BROWNFIELDS The American Society for Testing and Materials ASTM defines brownfields as abandoned idled or underutilized properties where expansion or redevelopment is complicated by the potential or confirmed existence of chemical s of concern. The . Environmental Protection Agency EPA Web page states Brownfields are abandoned idled or under-used industrial and commercial facilities where expansion or redevelopment is complicated by real or perceived environmental contamination. In the mid-twentieth century brownfield was a planners term for urban blight. Brownfields had existed for decades perhaps centuries but a strong focus on cleaning up these properties did not happen until the 1970s see Table 1 . Concurrent with the federal use of brownfields several local and state governments adopted the term for their efforts to bring about economic revitalization. Most governments have adopted specific legal definitions of brownfields. These definitions reflect differing environmental and economic conditions but have strong similarities to the federal definition. In everyday language a brownfield is an area that is con-laminated or perceived to be contaminated. Most brownfields can be redeveloped revitalized and reused after assessment and cleanup. The EPA s brownfields program helps communities work together to create jobs and put abandoned properties back into productive use. The EPA together with other federal state and local agencies provides funds coordination and advice for the cleanup of brownfields. Politically brownfields have been contrasted to greenfields. Greenfields are rural areas that are in danger of being converted to industrial areas. The goals of many brownfield programs include saving farmland and open spaces in addition to putting brownfields back into industrial use. Development of greenfields can be economically and environmentally problematic because it means building shipping and utility infrastructures that are essential for most industrial .
