Environmental remediation is the removal of contaminants and/or pollution from different parts of the environment as surface water, ground water, soil, or sediment. These contaminants could impact negatively on human health, the environment or both. Once environmental remediation has been requested by the government or an authority of land remediation, action should be taken immediately.
Environmental remediation is very site specific, and the cost will vary from site to site. This is due to the different environmental characteristics of a particular site, the contamination that is present, and the technologies that are available for cleanup.
With remediation, standards vary depending on the country. In the United States, the most comprehensive set of Preliminary Remediation Goals is from the EPA, or also known as the Environmental Protection Agency. Once a site is suspected of having been contaminated, it will need to be assessed. Often times, nearby sites that have been leveled, filled, or reclaimed can also have been contaminated. So, it is important to test the topsoil, surface, and groundwater of nearby properties as well before and after any environmental remediation efforts.
There are many different remediation techniques that are used to remove the different types of contaminants or pollution from the various different environmental mediums. Let’s take a look at some of the different types of remediation technologies and treatment options.
Soil Vapor Extraction (SVE) is a good remediation technology for soil, and Multi Phase Extraction (MPE) is an effective remediation technology when both soil and ground water are going to be remediated together. SVE and MPE though they both remediate, use different technologies to treat the off-gas volatile organic compounds (VOCs), which are generated after air has been removed by vacuum, as well as vapors, and VOCs from the subsurface. These technologies include most commonly granular activated carbon, catalytic and/or thermal oxidation and vapor condensation.
Bioremediation is the treatment of environmental problems through biological means. In bioremediation, either bacteria that occurs in nature or bacteria being specially bred is used to consume contaminants from extracted groundwater.
The use of nanoparticles -which are particles between 1 and 100 nanometers in size, are being explored to treat contaminated environmental materials such as wastewater, soil, and groundwater just to name a few. During nanoremediation, nanoparticles must be brought into contact with the contaminant – typically in a pump-and-treat process. Nanomaterials degrade organic contaminants through a reduction-oxidation reaction or adsorb to and immobilize metals such as lead and arsenic.
Pumping and treating uses a vacuum pump to remove any contaminated ground water by pumping it out, and allowing the removed ground water to be purified. This is done by slowly proceeding through a series of vessels that contain materials that have been designed to adsorb the contaminants from the groundwater. Different additives and filters may be added to help with the removal of contaminants depending on the type. In example, activated carbon would be used to help with removal of petroleum contamination.
Research is continuously ongoing to find new and better remediation techniques and to improve the current techniques.