Since the industrial revolution humans have exploited the Earth’s resources to an unprecedented amount. Destructive, unmonitored extraction practices and operations that were carried out before the implementation of environmental laws and regulations have left hundreds of sites contaminated. Harmful substances at these sites have negative impacts on the health of both people and animals in the area. Environmental remediation sets out to reduce these toxic substances, particularly the removal of contaminants from soil, groundwater, sediment, and surface water.
Platforms for Discussion of Environmental Issues
Awareness is the first step in environmental remediation, but there must be concerted effort to bring the the public into the discussion so they are better able to elect officials that support environmentally sound practices. While public awareness has increased with films like The Inconvenient Truth, there are an increasing number of issues that need constant and consistent action. For problems that effect specific regions, targeted efforts and local outreach through trade-shows and public forums can be effective options. Classroom education is essential to bringing up a more informed citizenry. The media must also play its part in reporting the issues in an informed and fair manner. It isn’t enough to involve only industrialized nations; environmental remediation is equally, if not more, critical in the developing world where many of the world’s most important eco-systems exist.
Remediation Efforts for Groundwater and Soil
The U.S. Department of Energy (DOE) now manages one of the largest groundwater and soil remediation efforts on the planet. Contaminated sites include some 6.5 trillion liters of groundwater and 40 million cubic tons of soil and debris that are infected with radionuclides, metals, and organics. Efforts by the DOE and many environmental firms are carried out through a number of methods ranging from active engineered systems to natural attenuation.
Technologies and Treatment Strategies
A variety of groundwater and soil remediation technologies and treatment strategies are catalogued by the Environmental Protection Agency and carried out by a number of organizations and firms. It’s a multi-faceted approach that involves different procedures falling under the three main categories of treatment: biological, chemical, and physical. Decontamination usually involves combining methods that span all three categories.
Biological Treatment Technologies
This type of remediation for groundwater focuses on treating the water through biological methods, the most popular methods being bioaugmentation, bioventing, bioslurping, and phytoremediation. Bioaugmentation involves adding strains of inoculation that are known to degrade the contaminants. Bioventing uses microorganisms to break down contaminants and is particularly common when dealing with fuel residuals. The addition of vacuum-enhanced pumping to bioventing is known as biosurping and the use of trees and plants to remove soil contaminants is phytoremediation.
Chemical Treatment Technologies
Remediation may also be carried out through a number of chemical treatment processes, including both solvent extraction and chemical oxidation. Using solvent extraction has been particularly useful for the removal of PCBs and similar chemicals that stick to soil and sediment. Chemical oxidation breaks down the harmful chemicals into innocuous compounds like water and carbon. Chemical treatment methods tend to be favored for their lower costs which are largely due to the processes being completed on-site.
Physical Treatment Technologies
Physical treatment processes focus on removing the substances and are often combined with other treatment methods. Pumping and treating is one of the more popular groundwater treatment methods and involves physically pumping the groundwater to the surface and then treating it through biological or chemical means. Air sparging and dual phase vacuum extraction are two other methods that pump air into the contaminated area to raise contaminants and use a high-vacuum system to rid the groundwater/soil of pollution, respectively.