Divisibility, Apportionment & Allocation

Apportionment and allocation analysis & consulting.

Demonstrating divisibility among potentially responsible parties (PRPs) requires consideration of site-specific factors, including a site's physical setting, history, and use(s), and the types and extent of the associated contaminants. Because of the joint and several liability imposed on PRPs, apportionment or allocation is of particular interest to clients who may have greater liability and financial resources than other PRPs, and to PRPs who believe they have a minor contribution to contamination.

For decades, Exponent has supported clients by developing technically sound apportionment-of-liability and allocation strategies and presenting our analyses for consideration by courts and in alternative dispute resolution settings.

Using historical and technical site-specific information, we can develop specific defensible allocation factors to assist the allocator, or the court, in assigning relative responsibilities and costs to PRPs. These factors may include:

• Relative timing and duration of ownership and operation
• Historical operations
• Quantity of contaminants released to the environment
• Estimated timing and duration of releases
• Chemical fingerprints of the contaminants
• Distribution of the contaminants in soil, groundwater, and sediment

Data used to establish allocation factors may range from a review of historical records to more complex considerations, such as chemical fingerprinting and statistical chemical source models to estimate source contributions. With our extensive understanding of industrial processes and the environmental behavior of the chemicals associated with these processes, Exponent is uniquely qualified to assess release sources and differentiate environmental damages among multiple parties.