The need for site investigation is common to cleanups under any regulatory program. An investigation can occur at all points in the cleanup process, from initial site assessment through waste site closeout. A site investigation generally is undertaken to:
- Confirm the presence or absence of specific contaminants
- Delineate the nature and extent of environmental contamination
- Identify contaminant sources
- Provide the data necessary to assess potential risk to human health and/or the environment
- Gather the data needed to determine if a remedial action should be taken
- Understand site characteristics impacting the remedy design, construction, or operation and closeout, and
- Evaluate performance of a remedial action.
Site investigations typically involve sampling of soil and groundwater using various drilling and well installation technologies and analysis of samples at offsite laboratories. Investigations also may include sampling of sediment, surface water, soil gas, or indoor air; searching for underground storage tanks (USTs) or other buried objects; or evaluating demolition material containing asbestos, lead-based paint, or other toxic products.
Planning for Site Investigation
Consideration of green remediation options early during the project design phase will help reduce cumulative environmental footprints of a cleanup. Effective planning will include identification of investigative decision points in context of a site’s unique contamination scenario and logistics, while accounting for potential remedies and anticipated site reuse.
At each decision point, strategies and methods can be evaluated to determine which are likely to best address the core elements of a green cleanup:
- Reducing total energy use and increasing renewable energy use
- Reducing air pollutants and greenhouse gas (GHG) emissions
- Reducing water use and negative impacts on water resources
- Improving materials management and waste reduction efforts, and
- Enhancing land management and ecosystems protection.
A green site investigation relies on information gained from a thorough preliminary assessment that identifies target areas and site conditions through minimally intrusive techniques. Use of innovative field analytics and direct sensing tools can reduce the environmental footprint of follow-on characterization or cleanup activities, particularly by limiting mobilizations in the field and increasing the density of analytical data. More targeted remedial actions and “surgical” removal actions also can be achieved through use of high resolution sampling tools during site investigations.
Initial BMPs for a site investigation include:
- Evaluating feasibility of using a mobile laboratory, field analytical methods, or direct sensing tools
- Scheduling activities for appropriate seasons to reduce delays caused by weather conditions and fuel needed for heating or cooling
- Identifying local sources of energy efficient machinery and vehicles and alternative fuels
- Establishing electronic networks for data transfers and deliverables, team decisions, and document preparation, and selecting electronic products on the basis of comparisons available in the Electronic Product Environmental Assessment Tool (EPEAT® )
- Selecting facilities with green policies, for worker accommodations and periodic meetings
- Reducing travel through increased teleconferencing, compressed work hours, and flexible work locations, and
- Identifying options for integrating renewable energy resources, including those extending throughout cleanup activities.