Issue of Lead Contamination in Public Housing Estates

To decontaminate polluted soils, there are numerous environmental remediation methods used to lessen the chance of causing more harm at the site and to the environment especially during heavy rains. This includes on-site treatment and off-site removal of the contaminated soil. But because these cannot provide total clean up the contaminated land, environmental remediation contractors employ more than one technique. check it out The three methods used to remediate the contaminated land are:


• Physical removal and containment of polluted soil
• Soil washing
• Bioremediation

Isolating and Containing Contaminated Soil
The land containing polluted soil is cleaned up through the physical removal of contaminated soil. In this clean up method, people dump the soil in a landfill or incinerate in. However the downside of this method is that it can cause new problems such as air pollution through burning the toxic material or incarcerating the polluted soil without decontamination.

Liquid or solid contaminants can chemically or physically mix with soil particles. The type of contamination will determine the treatment method that will be used. Generally, heavy metals are broken down into compounds that can’t react with other materials while toxic organic chemicals like solvents and pesticides are incinerated.

In landfills, containment method is used and it incorporates the use of impermeable layers of plastic liners and dense clay caps. In order to prevent spreading the contamination from rain water run-off the soil is isolated on-site.

Soil Washing
This is pump-and-treat method wherein chemical solvents are used to remove toxic materials from the soil. Polluted soil is cleaned up in place without the need to excavate. Chemicals are pumped into the ground so that harmful toxins are flushed away from the ground moving them toward wells that pump it out for processing. This method works best if the soil beneath the polluted area is like clay meaning not permeable.

Chemical treatments using organic and inorganic acids and chelating agents are used to remove heavy metals. However, secondary hazardous wastes are generated by this method which would even require additional treatment.

Solvents and heating oil are contaminants and they can be present in the soil in the form of liquids and can slowly and eventually dissolve into the groundwater. In this case, to dissolve these pollutants, environmental contractors make use of chemicals such as detergent-related surfactants, and cosolvents like ethanol or methanol.

Bioremediation method
This method is considered to be the safest for the environment. It entails inciting the growth of naturally occurring waste-eating microorganisms in order to degrade organic contaminants in the soil. This can be carried out at the site or after excavation. Contaminants are broken down by microorganisms as they use them as a source of food during the aerobic processes, which requires oxygen.

In general, the slurry bioremediation method will be used by remediation contractors in case they used bioremediation method after removing the soil. This will keep the soil suspended and the microbes in contact with the contaminants by mixing the soil in water.

Another bioremediation method is the solid-phase wherein the excavated soil is placed in an isolated area wherein it is being tilled with water and nutrients in order to facilitate the growth of the microorganisms. Remediation contractors work in environmental construction projects and help with disaster recovery. They are a team of environmental experts that can help you address any challenging contamination issue through employing good teamwork, the best technique and the right technology.