HP3 Metals in the Environment: Regulatory and Risk Concerns
254 Portland Ballroom
1:20 PM - 5:20 PM, Thursday
() Implementation of copper regulations based on the Biotic Ligand Model (BLM): challenges and opportunities.
Bartee, M1, Edge, D1, Erickson, M2, Sueker, J3, 1 Blasland, Bouck & Lee, Inc., Carpinteria, CA, USA2 Blasland, Bouck & Lee, Inc., Ann Arbor, MI, USA3 Blasland, Bouck & Lee, Inc., Golden, CO, USA
ABSTRACT- Until recently, monitoring and management of metals in the environment has been driven primarily by empirically-derived regulatory standards. Although empirically-derived standards provide some opportunity to consider site-specific conditions that affect bioavailability, exposure, and toxicity (e.g., hardness, pH, water effect ratios, and total-dissolved translators), they currently do not account for a number of important site-specific parameters that may ultimately regulate toxicity. In November 2003, the United States Environmental Protection Agency (USEPA) released a draft update to the Ambient Water Quality Criteria (AWQC) for copper that incorporates usage of the Biotic Ligand Model (BLM) to account for additional critical site-specific variables, representing a shift from empirically-derived criteria to mechanistically-derived criteria. The usage of the BLM to develop a standard to regulate copper in surface waters of the United States carries with it a number of implications for regulators, the regulated community, and investigators. Whereas in the past copper concentration, water hardness, and pH were the primary focus of assessments of standard attainment, ecological risk, and the relationship between water quality and copper toxicity, under the new BLM paradigm, an expanded set of tools and data must be mastered, measured, and potentially managed, to ensure the protection of ecological receptors in surface water. This presentation will examine the implications of this new regulatory approach from hydrologic, chemical, toxicological, and ecological perspectives. Issues to be addressed include the spatial and temporal data needs, the applicability of this approach at sites with multiple metals of concern, the combination of this approach with other ecological risk assessment tools, and the incorporation of this approach into other existing regulatory frameworks.
Key words: copper, Biotic Ligand Model (BLM), ambient water quality criteria (AWQC), ecological risk assessment