Sometimes the cause and effect relationships that lead to environmental remediation can be fairly straightforward. In other circumstances, there can be significant uncertainty about various source contributions and/or the timing of contamination. In order to address these more complex contamination scenarios, Environmental Forensics typically involves the integration of various forms of information to develop a legally defensible basis for identifying sources of contamination and Potentially Responsible Parties (PRPs).
 

	Some sites need source deconvolution of intermixed contamination
	Some sites need historical contamination reconstruction to identify the responsible owner among a series of owners over time.
	Some sites need to separate background contamination from site specific contamination to determine an accurate contamination allocation to the overall magnitude of contamination.
	Some sites need all of the above!

Environmental Forensics can be performed for a range of matrices (soil, sediment, structures, water, and/or air). The information utilized in Environmental Forensic investigations can range from historical documents and operations designs to field data and numerical models. In some cases, Phase II or Phase III Environmental Site Assessment data may be sufficient in order to effectively perform an Environmental Forensics investigation to address the contribution and/or timing questions. Some sites would benefit from augmenting existing data and improving the site characterization in order to make more robust forensics conclusions. Such augmented data may include isotopic or chemical signature analysis, remote sensing imagery, or fate and transport modeling.

The Environmental Forensics goal of establishing robust and incontrovertible scientific evidence that identifies the source and/or timing on contamination has the potential to make legal proceedings quicker, more straightforward, and therefore less expensive.

In Part II, we will discuss a couple examples of how environmental forensics was able to provide the information needed on contamination source and timing using a scientifically defensible approach.