Quiz Modules 7 - 12 Flashcards
What is Phytoremediation?
It uses plants to accomplish either removal. containment or treatment of contaminants
What is Phytoextraction?
Plants are used to extract materials from the soil and transport the materials above ground where they can then be harvested and mitigated.
What is photostabilization?
Plants are used to limit the mobility of contaminants on a site.
What is Photovolitilization?
Plants are used to extract contaminants from the ground. A chemical reaction in the plant allows the contaminant to volatilize into the air.
What are some advantages of Photoremediation?
- Can be used in-situ
- Liability does not need to be transferred
- Relatively inexpensive
- Useful for petroleum hydrocarbons, PAHs, and salts
- Can be used on wellsites
- Can be used on remote locations where access is limited
- Remediation to guidelines is often accomplished in 2-3 growing seasons
- Uses solar energy
- Often readily accepted by the public
What are some disadvantages of Photoremediation?
- Takes time
- Plants can be invasive
- There may not be plants capable of remediating some contaminants
- Need to dispose of the byproduct
- Multiple contaminants may pose a problem
- Contaminants below the rooting zone may not be able to be remediated
- Only suitable when contamination concentrations are low enough to allow plants growth
- May require some actions to improve soil structure to allow plant growth.
List some additional remediation methods.
- Air Sparging
- Soil Vapour Extraction
- Pump and Treat
- Permeable reactive barriers
- In-situ-bioremediation
- Funnel and Gate system
- Soil Washing Method
- Solidification and Stabilization Method
What is Air Sparging?
Compressed gas is injected into the saturated zone, contaminants are volatilized and move up into the unsaturated zone, the contaminant vapours are then extracted using a vacuum system.
What is Soil Vapour Extraction?
Compressed gas is injected into the unsaturated zone, contaminants are volatilized and extracted using a vacuum system.
What is Pump and Treat?
The pump and treat method involves the removal of dissolved contaminants to the surface. At the surface contaminated water is treated.
What is the Permeable Reactive Barrier Method?
A reactive barrier is installed to intercept contaminated groundwater. The barrier is intended to react with the contaminants. Contaminants can be adsorbed by the barrier, degraded or precipitated.
What is In-situ-bioremediation?
This method uses micro-organisms in the soil to metabolize contaminants and break them down into materials that are not toxic to humans or the environment.
What is the Funnel and Gate system?
Another version of the permeable reactive barrier (PRB) is the funnel and gate system. The main difference is that impermeable materials are used to create a subsurface funnel to force groundwater into an area where highly permeable reactive material has been deposited. The reactive material in this case is called the gate.
What is the Soil Washing Method?
Contaminated soil is removed from the area and water is used to separate the fine soil material from the larger particles of sand and gravel.
What is the Solidification and Stabilization Method?
Additives and introduced to the contaminated area solidifying the contaminant and stabilizing it in place.
