Remediation
Remediation is a term used to describe the removal of pollution or contaminants from land (including sediments) for the general protection of the environment or, quite commonly, from a brownfield site so that it can be reused. The reuse of brownfield sites is part of the urban consolidation movement and allows the regeneration of decaying former industrial areas, sometimes for industry, but often for high density housing, particulalry in areas of scenic beauty (along Harbours and rivers) and close to the CBD of a city or major transport infrastructure such as railway stations.
Remediation is generally subject to an array of legislation, and is based on assessments of health and ecological risk where there are no legislated standards or where standards are advisory (often called Preliminary Remediation Goals -PRG's).
Some technologies are controversial, particularly anything involving incineration because of the risks of dioxin forming in the atmosphere as the exhaust gases cool. For this reason remediation proponents often use terminolgy like thermal oxidiser and direct thermal desorption to minimise the risk of the community thinking about incineration risks.
Monitoring for compliance against each standards is critical to ensure that exceedences are detected and reported both to authorities and the local community.
Enforcement is necessary to ensure that continued or significant breeches result in fines or even jail/gaol for the remediator.
Penalties must be significant as otherwise fines are treated as a normal expense of doing business. It must be cheaper to comply than have continuous breeeches.
For an example of a complete rezoning by a state government over the opposition of local government and local communities of former chemical plants to fund remediation to allow for redevelopment for high density residential, retail and office development see http://rhodesnsw.org
In this case the proposed rezoning, remediation and redevelopment has a wealth of material available through the internet from:
The remediation of Homebush Bay is impoertant because of its impact on the food chain which extends through benthos not only to local protected and threatened species of birds, but also to JAMBA and CAMBA protected species and species which use other RAMSAR protected wetlands. Ultimately human health is impacted through the food chain. Homebush Bay has a complete fishing ban, there is a commercial fin fishing ban west of the Gladesville Bridge, and based on submissions of the remediator and NSW Waterways and EPA the complete fishing ban ought be extended to the whole of the Parramatta River west of Homebush Bay and at least as far East as the Ryde Traffic Bridge.
Use http://www.google.com and other search engines to search for related sites in addition to using the links below.
Please add any links that relate to remediation under the headings below:
Remediation Standards
The most comprehensive set of PRG's is from US EPA Region 9, although the Canadian EPA also has a comprehensive spreadsheet of PRG's. There is also a set of standard used in Europe commonly called the Dutch standards. The EU is rapidly moving towards European wide standards, although most of the industrialised nations in Europe have their own standards at presentSite Assessment
Once a site is suspected of being seriously contaminated there is a need to assess it. The historical use of the site and the materials used and produced on site will guide the nature of testing to be done. Often nearby sites owned by the same company or which are nearby and have been reclaimed, levelled or filled are also contaminated even where the current uses seems innocuous. For example, the car park may have been levelled by using contaminated waste in the fill. It is also important to consider off site contamination or nearby sites often through decades of emissions to air and dust. Ceiling dust and topsoil of nearby properties should be tested both before and after the remediation. This is a controversial step as:
Often corporations which do voluntary testing of their sites are protected from the reports to environmental agencies becoming public under Freedom of Information laws, however a Freedom Of Information inquiry will often produce other documents that are not protected or will produce references to the reports.Funding Remediation
In the US there has been a mechanism for taxing polluting industries to form a Superfund to remediate abandoned sites, or to litigate to force corporations to remediate their contaminated sites. Other countries have other mechanisms and commonly sites are rezoned to "higher" uses such as high density housing, to give the land a higher value so that after deducting clean up costs there is still an incentive for a developer to purchase the land, clean it up, redevelop it and sell it on, often as apartments (home units).Remediation Technologies
Remediation technologies are many and varied. The best source of information is probably http://www.clu-in.org/ Community Consultation and Information
In preparation for any significant remediation there should be extensive community consultation. The proponent should both present information to ans seek information from the community. The proponent needs to know about "sensitive" uses like childcare, schools, hospitals, and playgrounds as well as community concerns and interests information. Consultation should be open, on a group basis so that each member of the community is informed about issues they may not have individually thought about. An independent chairperson acceptable to both the proponent and the community should be engaged (at proponent expense if a fee is required). Minutes of metings including questions asked ant the answers to them and copies of presentations by the proponent should be available both on the internet and at a local library (even a school library) or community centre.Incremental Health Risk
Incremental Health Risk is the increased risk that a receptor (normally a human being living nearby) will face from the remediation project. The use of incremental health risk is based on cancer and non cancer effects such as reproductive abnormalities and often involves value judgements about the acceptable projected rate of increase in cancer. In some jursdictions this is 1 in a million, but in other jurisdictions it is 1 in 100,000. A relatively small incremental health risk from a single project is not of much comfort if the area already has a relatively high health risk from other operations like incinerators or other emissions, or if there are other projects at the same time causing a greater cumulative risk or an unacceptably high total risk. An analogy often used by remediators is to compare the risk of the remediation on nearby residents to the risks of death through car accident. Dust, Noise, Odour, Groundwater, Sewer, Air, Waterways
There should be standards set for the levels of dust, noise, odour, emissions to air and groundwater, and discharge to sewer or waterways of all chemicals of concern or chemicals likely to be produced during the remediation by processing of the contaminants. These should be compared against both Background levels in the area and standards for areas zoned as nearby areas are zoned and against standards used in other recent remediations. Just because the emission is emanating from an area zoned industrial doesn't mean that in a nearby residential area there should be permitted any exceedences of the appropriate residential standards. Transport, Hazop, Waste, Emergency, Safety Induction
Assessment should be made of the risks of operations, transporting contaminated material, disposal of waste which may be contaminated including workers clothes, and a formal emergency response plan should be developed. Every worker and visitor entering the site should have a safety induction tailored to their involvement with the site.Impacts of Funding Remediation by Higher Use Rezoning
The rezoning is often resisted by local communities and local government because of the adverse impacts on the local amenity of the remediation and the new development. The main impacts during remediation are noise, dust, odour and incremental health risk. Then there is the noise dust and traffic of developments. Then there is the impact on local traffic, schools, playing fields, and other public facilities of the often vastly increased local population. Example of a Major Contamination, Rezoning, Remediation & Redevelopment Project involving Land and Sediments and a Mix of Final Uses including Open Sspace, High and Low Rise Apartments, Retail Centre and Office Space
This rezoning, remediation and redevelopment of land contaminated by Union Carbide, ICI and others also involves the remediation of a strip of dioxin contaminated sediments in Homebush Bay. The Homebush Bay area was home to the main events of the Sydney 2000 Summer Olympics. The sediments were dealt with in the Commission of Inquiry into the Lednez site formerly owned by Union Carbide, but not to the satisfaction of local community activists.
External Links
Remediation Standards, PRG's
US EPA Region 9 PRG's
Canadian EPA Summary TableRemediation Technologies
Legislation about remediation
(Please note the nation or state,nation in which it applies in brackets)
Superfund
Contaminated Land Management Act (NSW, Australia)Environmental Groups with Information
(Please note the Country or state, country in which they operate in brackets)
CHEJ (US - Grew out of Love Canal controversy)
Greenpeace (International organisation with National sites)Environmental Protection Agencies
(Please note the Country or state, country in which they operate in brackets)
US EPA
US EPA Region 9
Environment Australia
NSW EPA (NSW, Australia)Major Remediation Projects
(Please note the city, state, country in which they are located, the polluter, the major chemicals of concern and the proposed new use in brackets)
http://rhodesnsw.org (Rhodes, NSW, Australia - Union Carbide - dioxin - High density residential, retail offices, open space)