The MPCA wants to change Minnesota’s water quality rules. Why, and why now?

The Minnesota Pollution Control Agency wants to change the rules on water quality. The agency has been working on these rules for a few years and hopes to put them into effect this summer.

The plan looks like a sort of Rubik’s cube, eliminating subcategories, moving limits from one category to another, and doing away with many numeric pollution limits in favor of a narrative description requiring a “translator.” Structured like a flowchart, the translator asks a series of questions designed to determine whether a particular effluent is likely to contribute to an exceedance of the criteria set in the narrative.

The idea is now being studied by an administrative law judge, who is reviewing the agency’s technical documents along with written and oral comments submitted by interested parties. The judge will make a recommendation to the MPCA at the end of March. Comments are still being accepted.

The plan has the support of several industry groups, notably taconite mining, and many Minnesota cities like it because their wastewater treatment plants face possible enforcement of what they describe as the “existing outdated standards.” Many environmental groups, including Clean Water Action, Friends of the Boundary Waters, the Izaak Walton League and the Sierra Club, and several tribal governments, including the Fond du Lac Band and the Grand Portage Band of Lake Superior Chippewa are lined up against it; they charge that the MPCA is bowing to industry pressure.

First, it’s important to understand that the state applies rules to waters based on their defined beneficial uses:

Class 1    Domestic consumption, drinking water
Class 2    Aquatic life and recreation
Class 3    Industrial use and cooling
Class 4A Crop irrigation
Class 4B Watering for livestock and wildlife
Class 5    Aesthetics and navigation
Class 6    Other uses
Class 7    Limited resource value water

Most waters are assigned more than one beneficial use, and the standards that provide the highest level of protection apply. Most of Minnesota’s rivers and lakes are included in Classes 3 and 4.

Currently, water quality rules include both narrative and numeric standards. A narrative standard prohibits unacceptable conditions, for example: for Class 3 (industrial) uses, the water quality “shall be such as to permit their use for industrial cooling and materials transport without a high degree of treatment being necessary to avoid severe fouling, corrosion, scaling, or other unsatisfactory conditions.”

Here’s an overview of what the MPCA is proposing to do:

For Class 3: Consolidate three subclasses, remove numeric standards for hardness (calcium and magnesium) and update narrative standards.

For Class 4A: (irrigation): Remove numeric standards for bicarbonate, conductivity and sodium, and update narrative standards.

For Class 4B: (livestock and wildlife):…