Environmental remediation involves the removal of pollutants and contaminants from the soil, groundwater, and other mediums that may have been affected by human activity. The remediation process often involves in-situ chemistry evaluation to determine the appropriate chemicals or solutions to remove the pollutants. The selection process requires careful consideration of several factors, including site characterization, hydrogeology, chemicals of concern, and total mass of constituents to be removed. Additionally, remediation timelines should also be considered as part of the selection criteria.
Site characterization involves the evaluation of a site to determine the type, extent, and concentration of pollutants present. This information is essential in selecting the appropriate chemicals or solutions to remove the pollutants. The type of pollutant and its concentration will influence the choice of remediation method, whether it is chemical, physical, or biological. For instance, if the pollutants are petroleum hydrocarbons, chemical oxidation or bioremediation may be appropriate. If the pollutants are heavy metals, chemical precipitation or soil flushing may be the best approach.
The hydrogeology of the site is also crucial in selecting the appropriate chemicals or solutions for remediation. Understanding the groundwater flow direction, hydraulic conductivity, and other factors is essential in determining the most effective way to deliver the treatment solution to the target area. For example, if the site is composed of sandy soils with a high hydraulic conductivity, a solution with a low viscosity and low surface tension may be required to ensure proper distribution.
Chemicals of concern are substances that pose a risk to human health or the environment. They are typically regulated by environmental agencies, and their presence can trigger remediation. The selection process should consider the specific chemicals of concern and the appropriate chemicals or solutions to remove them. For example, if the chemicals of concern are Chlorinated Solvents, then an emulsified zero valent iron chemical solution such as SourceKill, or chemical oxidation with permanganate or persulfate may be the best option.
The total mass of constituents to be removed is also a crucial factor in selecting the appropriate chemicals or solutions for remediation. The mass of contaminants will influence the amount and type of chemicals required for remediation. Therefore, if the site has a large mass of contaminants, a more aggressive remediation method may be required.
Finally, remediation timelines should be considered as part of the selection criteria. The timeline for remediation may be driven by regulatory requirements or client needs. The selected remediation approach should be capable of meeting the required timeline, and the chemicals or solutions should be effective within the specified timeframe.
In conclusion, in-situ chemistry evaluation is a critical component of environmental remediation. The selection process requires careful consideration of several factors, including site characterization, hydrogeology, chemicals of concern, total mass of constituents to be removed, and remediation timelines. The appropriate chemicals or solutions should be selected based on these factors to ensure effective and timely remediation. It is recommended that you work with an experienced engineering and environmental consulting firm who understand the site geology, in-situ chemistry options available and most appropriate to remediate chemicals of concern, and one who knows the regulatory framework the site will be expected to adhere to meet remediation objectives.