The identified contaminant in concentration must be higher than what is normally expected from a non-contaminated site. Lastly, it poses a certain threat to people and/or the environment because of its location and concentration (Project Participants and their Organizations 2003).
Various physical and chemical properties are considered as hazardous substances, and hence, pose a threat to people are toxicity, carcinogenicity, corrosiveness, combustibility, explosiveness, and asphyxiation. The contamination of land and its surrounding areas can vary according to its nature and degree of severity.
Risk management is one effective technique in addressing problems brought about by contaminated sites. It is defined as the culture processes and structures directed towards the effective management of potential opportunities and adverse effect (Project Participants and their Organizations 2003). In the context of contaminated sites, risk management is understood as the process of gathering information for purposes of informing decisions and minimizing the risks or adverse effects of a contaminated site to people and the environment (Project Participants and their Organizations 2003).
Estimating the probability of an event occurring and the likewise magnitude of effects are what involve risk assessment. Risk assessment is essentially important in risk management since it provides the information needed in responding to a potential risk (Project Participants and their Organizations 2003). Environmental risk assessment is an available technique for dealing with contaminated sites, which involves the management of natural hazards (flooding, landslides), water supply, wastewater disposal systems, and contaminated sites. Another available technique for dealing with contaminated sites is conducting human health risk assessment, which is one form of risk management that focuses on assessing the risk to people and communities from hazardous substances. The risk assessment for contaminated sites is focused on the human health, since a large number of known potentially contaminated sites are located in urban areas where people abound.
Regional councils can be formed in order to address managing discharges of contaminants, which may be managed through policies and rules. They can also provide information and technical assistance on good management practices for sites. Integrated contaminated land databases can also be developed in order to provide information about contaminated land.
Remediation is another technique that may be employed for dealing with contaminated sites. Remedial actions may be utilized and implemented in ensuring a reasonable land-use and in protecting ground water. Both technical and economic aspects are incorporated in the optimal solution (COWI, 2008). In averting risks from many types of pollutants, traditional remediation techniques such as excavation and remedial groundwater abstraction can be used. An advanced technology approach to remediation is more advantageous in some situations, both economically and environmentally. Single methods or combinations of methods can be employed in dealing with contaminated sites, which may include soil ventilation, vacuum extraction, bio-ventilation, air sparging, and bio-sparging. With the use of chemical oxidation and potassium permanganate, effective remediation of