MPCA proposes water-quality standards

Every three years, the U.S. Environmental Protection Agency requires states to review, update and — in many cases — strengthen their water-quality standards. Minnesota is in the middle of one of those reviews, and, for the first time, regulators are proposing setting a standard for phosphorus – a common pollutant that feeds algae growth – in rivers and streams.

The Minnesota Pollution Control Agency also is considering toughening its standard for nitrate in rivers and lakes by weighing, not just the pollutant’s impact on human health, but also its effect on fish and other organisms in the water. The agency is considering measuring turbidity in a new way and establishing a new standard for a chemical compound — nonylphenol – that is formed from chemicals once widely used in industrial detergents and pesticides and in the production of paper. The compound is banned in Europe, and the EPA is working to phase out its use in the U.S.

The MPCA has announced its intent to set or upgrade the standards for phosphorus, nitrate and nonylphenol, but numerical limits have not been made public. Once the limits are proposed, probably by late spring, citizens will have until fall to informally comment on them. The changes will be subject to a hearing before an administrative law judge next year.

The Freshwater Society interviewed Mark Tomasek, a supervisor in the agency’s water quality standards unit, about the rule changes. To read the question-and-answer interview from the Facets newsletter, go to the Freshwater Society web site or click here.