The Minnesota Pollution Control Agency will hold public hearings in front of a state administrative law judge Thursday on proposed changes in the state's rules on water quality.

The first hearing starts at 9 a.m. with a second at 6 p.m. in St. Paul, at the PCA headquarters, but also via video conference at the PCA offices in Duluth and Mankato.

Anyone attending in Duluth or Mankato will have the opportunity to speak live by video with the administrative law judge.

The changes officially adopt requirements by the federal Environmental Protection Agency to modernize water quality rules under the federal Clean Water Act.

Federal antidegradation regulations require states to adopt antidegradation policies and identify ways to maintain and protect existing uses - swimming, fishing, drinking water - to prevent unnecessary degradation of existing high water quality and maintain and protect the quality of waters identified for their outstanding value.

The new rules have been in the works for nine years and come after a series of fits and starts, multiple public input sessions and years of agency drafts. The current rules haven't been changed since 1988 and both the science, policy and social awareness of pollution have changed much since then, said Carol Nankivel, who is heading the effort for the PCA. When the original rules were written there was no such thing as storm water permits, she noted, which are now required of many developments.

PCA officials say the new antidegradation rules are designed to better protect more pristine lakes and rivers, or waters cleaner than the average body of water. If a company or other entity was permitted to discharge a regulated pollutant into a waterway, it means the permit won't allow them to pollute more just because the water body has greater "pollution capacity." For example, the Minnesota River is more polluted than the St. Croix River, but that does not mean more pollution would be authorized for the St. Croix.

Nankivel said the new rules don't set specific limits for pollutants but lay out the groundwork for how those rules should be set and permits granted. The new rules also don't delve into new areas where permits had not been required, she said, noting they don't apply to agriculture.

The new rules do, however, require even small polluters to apply for permits even if their total pollution emitted is less than past permit limits.

The new rules also separate permits for point-source pollution, such as a specific discharge pipe, and non-point pollution such as runoff from urban streets.

So far only environmental groups have submitted criticism of the rule changes, Nankivel said. One group, WaterLegacy, says the new rules don't go far enough "to prevent pollution that harms fish, wild rice, wildlife and human health throughout Minnesota." The group also says the new rules may make it easier for mining companies to pollute the headwaters of streams.

"We believe the proposed rules violate federal law, conflict with Minnesota statutes and policies to protect waters of the state from degradation, undermine public participation and fail to provide a reasonable structure for antidegradation assessment,'' the group said in written comments. The new rules "would fail to protect Minnesota's high quality and outstanding resource value waters from degradation."

The administrative law judge will allow public comments for at least five days and maybe more beyond the public hearings. The judge's decision on the adequacy of the new rules will come later this year and the changes still need approval from the EPA, likely late this year or even into 2017.

Comments will be taken at the hearings, and written comments may be sent to minnrule7050.pca@state.mn.us or to Carol Nankivel, MPCA, 520 Lafayette Road, St. Paul, Minn., 55155-4194. For more information and to see the proposal, go to pca.state.mn.us/water/nondegradation-rulemaking.