The Evolution of Risk-Based Corrective Action

Corrective action has traditionally been a sequence of steps taken at a site where hazardous substances or petroleum have been released to restore the site to a pre-release condition. Under many current regulatory corrective action programs a number of steps have been defined. Each step must be completed and the results approved by the regulatory agency before the next step can begin. This has resulted in each step taking on a life of its own, with objectives existing for the sake of that step that are disconnected from the overall corrective action objectives. Unfortunately, the complexities and costs of the traditional corrective action process have left many properties' abandoned or in perpetual corrective action. Recently, however, there has been growing recognition that the traditional corrective action process must be modified to encourage faster and less costly corrective actions. To address these needed modifications and to develop a standard framework that incorporates and integrates site-specific risk-based decision making into the corrective action process, in 1995 ASTM developed Standard E-1739, "Guide to Risk-Based Corrective Action for Petroleum Release Sites& commonly referred to as RBCA (pronounced Rebecca). In 1998 ASTM expanded the RBCA framework to include all chemicals with the development of Provisional Standard PS104-98, &Standard Guide for Risk-Based Corrective Action.& The RBCA framework provides a three tier process that begins with a simple, conservative screening approach in Tier 1 and proceeds to more complex, site-specific evaluations in Tier 2 and Tier 3. The objective of RBCA is to provide for protection of human health and the environment while insuring that appropriate, cost-effective and technically defensible approaches and remedies are selected. This paper will discuss the evolution of the traditional corrective action process to a site-driven process and the fundamentals of the ASTM RBCA framework.