Environmental Compliance 101

Green remediation is a term used to describe the process of considering sustainable environmental practices during remediation of contaminated sites. The United States Environmental Protection Agency (EPA) published a Green Remediation Technology Primer in April 2008 to provide “topical introductory information” relating to Green Remediation. The EPA defines green remediation as “the practice of considering all environmental effects of remedy implementation and incorporating options to maximize net environmental benefit of cleanup actions.”

Green remediation asks us to consider all environmental impacts associated with remediation in an effort to limit collateral environmental damage while also considering future site use. A green remediation analysis considers the following core elements:

• Energy requirements
• Air emissions
• Water requirements and impacts on water resources
• Land and ecosystem impacts
• Material consumption and waste generation
• Sustainability or long-term stewardship

Green remediation strategies focus on minimizing collateral environmental damage while remediating contaminated properties as required by state and federal cleanup programs. Green remediation asks us to consider and reduce the entire environmental “footprint” of remediation. Traditionally, remediation involved either removing contaminants from soil or water and releasing them to the atmosphere or moving contaminated soils from the source area to a landfill. Both of these approaches use energy and cause a release of contaminants and greenhouse gases to the atmosphere. Green remediation principles should be considered during all phases of emergency response, site investigation and characterization, feasibility studies, remedy (system) design, remedy implementation and closure sampling.

Emergency Response
Emergency response activities are necessary and appropriate if there is an imminent threat to human health or the environment. In accordance with green remediation initiatives, the response should be limited to those activities necessary to abate the emergency while limiting the number of mobilizations to the site, equipment used and spreading of contaminants. Because green remediation is an evaluation of alternatives that consider all environmental impacts associated with an action, necessary and aggressive actions inherent with emergency responses do not often consider collateral environmental damage or the environmental “footprint” resulting from the action.

Site Investigation and Characterization
For any remediation program to be effective, adequate understanding of the geologic setting and distribution of contaminants is critical. Many technologies and tools are available to assist in site characterization but there is no substitute for collecting and analyzing representative soil and groundwater samples to document conditions. Green remediation principles ask us to carefully evaluate what information is necessary and that only necessary information is acquired. In other words, collect only enough information to characterize the site conditions and evaluate remedial options. The collection of the necessary information should be accomplished in a manner that minimizes mobilizations to the site and investigation derived waste (IDW) requiring offsite disposal or treatment. Additionally, local vendors and contractors should be used to minimize travel distances.

Feasibility Studies
The feasibility study is the step where green remediation principles could have the biggest impact in terms of considerations. Some level of feasibility study is conducted on every remediation project and green remediation adds a component to the feasibility evaluation process. Where traditional feasibility studies focus strictly on what it will take to cleanup soil and groundwater, green remediation expands the feasibility process to include evaluating overall environmental impacts associated with the remedial approach so that a remedy can be developed that minimizes collateral environmental impacts. In addition to selecting a remedial approach that cleans up the contamination, green remediation reduces the collateral environmental impact by evaluating the remedial approach’s energy use, emissions, waste generation and use of recycled materials. Some remedial options such as natural attenuation and bio-remediation are often greener than mechanical remedial approaches such as excavation and landfill disposal or more active remedial systems such as soil vapor extraction and air sparging.

As with the site characterization phase, site visits should be minimized and only necessary information should be collected. This might involve combining testing activities for various options during one testing phase. Again, good planning and efficiency is important.

System Design, Installation and Operation
Green remediation asks that the remedial approach limits energy needs and collateral impacts to the environment are minimized. To that end, systems should be designed to work efficiently and should not be unnecessarily oversized. Systems should also be designed to minimize waste generation and emissions. In many situations, systems can be shut down periodically to avoid continuous operation thus saving energy associated with the remedial action. Measures should be considered to limit site visits such as remote monitoring and controls.

When involved with a spill response or remedial action, consider the overall impacts to the environment resulting from the activities and consider green remediation principles to minimize the remedial “footprint” and collateral environmental damage.