ST. PAUL, Minn. (AP) - An administrative law judge holds hearings Thursday on proposed revisions to Minnesota's rules against degradation of its waters.

The Minnesota Pollution Control Agency has been working on the changes for nearly a decade. It says they provide a balanced approach for protecting water quality and sustainable economic development. It says the proposals are meant to better align the state's rules with federal policies, and that they don't expand the scope of the current rules or create new regulatory authority.

Environmental and tribal groups are sharply critical of the proposed changes, saying they're poorly drafted. Paula Maccabee of WaterLegacy says they contain "huge loopholes" that would allow for further degradation of Minnesota's waters.

The federal Environmental Protection Agency has recommended some revisions, while the Minnesota Chamber of Commerce is seeking clarifications.