Physical

Physical method of remediation generally involves the removal of the contaminants from the soil / water, such as:

• Free product removal: In water some contaminants e.g. oil / diesel / DNAPL & NAPL form a “free product” layer which can be removed from the water using oil skimmer / rope or tube skimmers and oil / water separators.
• Air stripping: In abstracted water certain dissolved contaminants e.g. volatile organic carbons (VOCs) can be removed by placing it through a stripper system which forces an air stream through the water which cause the VOCs to be removed into the air. The VOCs are then carried through into a further filtration system to absorb the VOCs
• Air sparging: Air is injected at high pressure into the saturated soil zone, absorbed VOCs are transferred into the vapour phase and the collected via extraction wells. Air sparging is commonly used in combination with SVE
• Soil Vacuum Extraction: A negative pressure is applied to the soil through a series of extraction wells, volatile contaminants bound to the soil are then mobilised into the vacuum stream. The extracted vapour is then passed through either a filter system or Catalytic Oxidation unit
• Dual Phase vacuum Extraction: Similar to SVE however this method can also be applied to both the soil and groundwater, it incorporates both a water and vapour treatment system.

Generally contaminated sites are quite complex and often require more than one type of technology. All the above methods can be used in combination with each other or with the chemical and biological methods.