Human Health-based Water Quality Standards Technical Support Document

Minnesota's human health-based water quality standards (HH-WQSs) provide protections for the beneficial uses of drinking water, fish consumption, and recreation. HH-WQSs were first adopted in 1990; since that time there have been significant improvements in risk assessment methods and policies both at the State and Federal levels. The revisions being considered to the HH-WQS methods in Minnesota's water quality rules (Minn. R. chs. 7050 and 7052) center on recent U.S. Environmental Protection Agency (EPA) guidance and Minnesota Department of Health's (MDH) Health Risk Limits (HRL) rule. These revisions incorporate the latest public health practices for development of HH-WQSs that when fully implemented will enhance protection for human users of Minnesota's surface waters. Like all WQSs, they serve as the basis for setting wastewater discharge effluent limits, assessing water quality, and determining if waters are impaired (do not meet WQS).