Section 7 of the Endangered Species Act (ESA) specifies that federal agencies must submit to the U.S. Fish and Wildlife Service and National Marine Fisheries Service a determination if their federal action would negatively impact any threatened and endangered species. These regular national ESA Consultations require that each agency must understand relevant regulations. GLEC assists U.S. EPA with developing a methodological framework to assist EPA regional staff regional offices with determination of risk to species from adoption of EPA 304(a) criteria in state water quality standards. This objective requires GLEC to analyze and assess the most appropriate methods for framework development, as well as to assist EPA with drafting a guidance document for shared internal use by the Agency and with stakeholders. Tasks include robust analyses and assessments of existing quantitative/statistical approaches (e.g., acute-chronic ratios, Interspecies Correlation Estimation), species sensitivity distributional analysis) being considered by EPA for predicting toxicity of priority pollutants to sensitive and surrogate aquatic species in Biological Evaluations, as well as a limited assessment of the uncertainties associated with the collective use of these predictive tools in the overall risk assessment/BE development process.