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Brownfields are abandoned, idled, or under-used industrial and commercial facilities where expansion or redevelopment is complicated by real or perceived environmental contamination.
In city planning, brownfield land, or simply a brownfield is land previously used for industrial purposes, or certain commercial uses, and that may be contaminated by low concentrations of hazardous waste or pollution and has the potential to be reused once it is cleaned up. Land that is more severely contaminated and has high concentrations of hazardous waste or pollution, such as Superfund or hazardous waste sites, does not fall under the brownfield classification.
The term "brownfields" first came into use in 1992, at a 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 U.S. EPA funded its first Brownfield pilot project in 1994.
The number of Brownfields in Canada has been estimated at more than 3,000. Many of these sites can be safely cleaned up to meet today's environmental standards.
Generally, brownfield sites exist in a town's industrial section, on land containing abandoned factories or commercial buildings, or other previously polluting operations. Small brownfields may also be found in many older residential neighborhoods. For example, many dry cleaning establishments or gas stations produced high levels of subsurface contaminants during prior operations and the land they occupy might sit idle for decades as a brownfield.
The Ministry of the Environment for Ontario maintains a voluntary brownfield registry that can be accessed by the public - Brownfields Environmental Site Registry
Barriers to redevelopment of brownfields
Many contaminated brownfield sites sit idle and unused for decades, because the cost of cleaning them to safe standards is more than the land would be worth after redevelopment. However, redevelopment of brownfield sites has become more common in the first decade of the 21st century, as developable land grows less available in highly populated areas, the methods of studying contaminated land become more precise and techniques used to clean up environmentally distressed properties become more sophisticated and established.
Many federal and provincial programs have been developed to assist developers interested in cleaning up brownfield sites and restoring them to practical uses. To encourage redevelopment, some provinces and municipalities have even spent considerable money assessing the contamination present on local brownfield sites, to quantify the clean up costs in an effort to move the brownfield redevelopment process forward (see Regulation of brownfields below).
In the process of cleaning contaminated brownfield sites, surprises are sometimes encountered, such as previously unknown underground tanks (USTs), buried drums or buried railroad tank cars containing wastes. When unexpected circumstances arise, the cost for cleaning up the brownfield land increases and as a result the clean up work is either delayed or stopped entirely. To avoid unexpected contamination and increased costs, many developers insist that a site be thoroughly investigated prior to commencing remedial clean up activities. The Hill Engineering Group will perform Phase I and Phase II Environmental Assessments to evaluate the environmental risk associated with the property.
Innovative brownfields redevelopment strategies
A number of innovative financial and remedial techniques have been employed in recent years to expedite the clean up of brownfields sites. For example, some environmental firms have teamed up with insurance companies to underwrite the clean up of distressed brownfields properties and provide a guaranteed clean up cost for a specific brownfield property, to limit land developer's exposure to environmental remediation costs and pollution lawsuits. The environmental firm first performs an extensive investigation of the brownfield site to ensure that the guaranteed clean up cost is reasonable and they will not wind up with any surprises.
Innovative remedial techniques employed at distressed brownfields properties in recent years include bioremediation, which is a remedial strategy that uses naturally occurring microbes in soils and ground water to expedite a clean up and in-situ chemical oxidation remediation, which is a remedial strategy that uses chemicals to enhance a clean up. Often, these strategies are used in conjunction with each other or in conjunction with other remedial strategies such as soil vapor extraction, which is a process in which vapor from the soil phase is extracted from soils and treated, which has the effect of removing contaminants from the soils and ground water beneath a site. Some brownfields with heavy metal contamination have even been cleaned up through an innovative approach called Phytoremediation that utilizes deep rooted plants to soak up metals in soils into the plant structure as the plant grows. Upon reaching maturity, the plants are removed and disposed of as hazardous waste, the metal contaminants are removed with the plants and with the end result being a cleaned up brownfield site ready for redevelopment.
Post redevelopment uses
Some state governments restrict development of brownfield sites to particular uses in order to minimize exposure to leftover contaminants on-site after the clean up is completed; such properties are deed-restricted in their future usage. Some legally require that such areas are reused for housing or for new commercial use in order not to destroy further arable land. The redevelopment of brownfield sites is a significant part of new urbanism. Some brownfields are left as green spaces for recreational uses.
For historical reasons, many brownfield sites are located close to important thoroughfares such as highways and rivers; their reclamation can therefore be a major asset to a city. The City of Portland, Oregon has pioneered the use of road and rail infrastructure to support the cleanup and reuse of brownfield sites. Another example is the Atlantic Station project in Atlanta, Georgia.
But one of the most well-known areas in the United States for brownfield redevelopment is Pittsburgh, Pennsylvania, which has successfully converted numerous former steel mill sites into high end residential, shopping and offices. Several examples of brownfield redevelopment in Pittsburgh include:
* In Homestead, Pennsylvania, where the site once occupied by Carnegie Steel has been converted into a successful commercial center, The Waterfront.
* In Pittsburgh's Squirrel Hill neighborhood, where a former slag dump for steel mills was turned into a $243 million residential development called Summerset at Frick Park.
* In the Southside (Pittsburgh) neighborhood, where a former LTV steel mill site was transformed into Southside Works, a mixed use development that includes high-end entertainment, retail, offices, and housing.
* In the Hazelwood (Pittsburgh) neighborhood, where a former Jones and Laughlin steel mill site was transformed into a $104 million office park called Pittsburgh Technology Center.
* In Herr's Island, a 42-acre island located on the western bank of the Allegheny River, where a former rail stop for livestock and meatpacking were transformed into Washington's Landing, a waterfront center for commerce, manufacturing, recreation and upscale housing.
Regulation of brownfields
To encourage redevelopment, Ontario’s environmental legislation provides general protection from environmental orders for historic contamination to municipalities, creditors and others. On October 1, 2004, this legislation will also provide property owners with general protection from environmental cleanup orders for historic contamination after they have appropriately remediated a site. Ontario’s new Record of Site Condition Regulation (O. Reg. 153/04) details requirements related to site assessment and clean up. The regulation will replace the Guideline for Use at Contaminated Sites in Ontario.
Wikipedia information about brownfield
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Brownfield land".
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