Contaminant fate and transport in the courtroom

Modeling of contaminant fate and transport in soils, groundwater, air and other environmental media can be a critical component of permitting, remedial action planning and design, site characterization, and source identification. Modeling of emissions and contamination can result in significant cost-savings as compared with additional sampling and analysis, and is frequently utilized by potentially responsible parties as well as governmental agencies for air permitting, remedial investigations, corrective measures studies, and engineering design. The science of modeling has been challenged in federal and state courtrooms across the country. Questions have been raised as to the reliability, predictability and specificity of contaminant fate and transport modeling by various adversaries, including former operators, neighboring owners, and liability insurers. This paper will discuss the scientific rigors of environmental modeling, its many uses and acceptability within the scientific community, as well as its limitations. The paper will also review and discuss recent court rulings and evidentiary issues regarding contaminant fate and transport modeling in litigation and related expert witness testimony.