Multimedia, Multi-pathway, and Multi-receptor Exposure and Risk Assessment (3MRA)
Multimedia, Multi-pathway, and Multi-receptor Exposure and Risk Assessment
As a result of their regulatory reform efforts, the Office of Solid Waste (OS) in November 1999 introduced a new open-architecture, multimedia, multi-pathway, and multi-receptor exposure and risk assessment methodology designed to support their Hazardous Waste Identification Rule (HWIR). The new modeling system, referred to as the 3MRA technology, is envisioned as the foundation for eventually integrating other regulatory support decision tools in the future. Toward that end, and with the goal of integrating predictive modeling needs across the Office of Solid Waste and Emergency Response (OSWER) rule-makings and a variety of other agency Program Office regulatory thrusts, there is a need to build upon the 3MRA technology system in several directions. Among these are 1) a collection of science support research activities focused on improving, and making more realistic, some of the existing physical, chemical, and biological processes algorithms found in the current system; 2) adapting the methodology for use at larger spatial scales, or for use in concert with larger spatial scale modeling systems; 3) adding provisions to make the methodology applicable to a variety of related regulatory support problems such as the surface impoundment study and other emerging needs (e.g., mining waste, RCRA Corrective Action, waste management/leaching/modeling, etc.); 4) adding the front-end capability for the user to input data for a specific site; 5) enhancing the technology with more comprehensive uncertainty assessment capabilities; 6) implementing a comprehensive independent testing and validation program; and 7) establishing an easily accessible, Internet-based distribution and support network for the user community.