EPA publishes criteria recommendations for water quality that can be used by states to ensure that the presence of substances in ambient waters does not represent an unreasonable threat to humans who may recreate in and on the water, consume fish from the water, or use the water as a drinking water supply. Approaches to deriving criteria to protect human health have evolved in recent years, and in some cases stretch the limits of reasonableness with respect to assumed exposures.
NCASI maintains expertise and resources that can be used by members, and the states in which they operate, to inform judgements about these criteria. The expertise and tools help reveal ways in which criteria can provide the desired levels of protection for human health without unnecessarily burdensome mandates for costly effluent controls.
USEPA’s 2015 National Human Health Water Quality Criteria (HHWQC) included revisions to many of the inputs used to derive the pre-2015 National HHWQC. This report presents background information on many of those inputs with a focus on new data and science.