Source: Star Tribune (MN), March 12, 2014
Posted on: http://envfpn.advisen.com
The Minnesota Pollution Control Agency (MPCA) has postponed a widely-anticipated decision on sulfate pollution, saying it needs more time to study variables in wild rice production and water quality before proposing any new rules.
Environmentalists and Minnesota Indian tribes had clashed with officials from the state’s mining industry over the need for tough regulation of sulfate, a type of mineral salt discharged by mines and other industry in northeast Minnesota than can harm rice stands.
The decision delays MPCA’s widely anticipated recommendation for a “sulfate standard” and raises the possibility that standards ultimately could vary from place to place.
“There’s a lot more analysis needed,” Commissioner John Linc Stine said. “Perhaps higher levels of sulfate can be allowed. It’s potentially variable from place to place.”
According to the MPCA’s report, scientific reviews so far have shown that wild rice waters can withstand higher levels of sulfate depending on the proportion of dissolved iron in the water. Sulfate can produce toxic hydrogen sulfide in the rooting zone of the plants, but a chemical reaction involving iron can render the sulfide harmless.
Naturally occurring sulfate is not common in northeast Minnesota, where most of the wild rice grows. The primary source of sulfate is what leaches off piles of waste rock and tailings ponds from a century of iron and taconite mining on the Range. Other industries, including wastewater treatment plants, contribute as well.
The issue has been closely followed by Native American tribes, seeking to protect the state’s wild rice waters, as well as the Minnesota Chamber of Commerce, representing mine operators and other industry. There have been three years of lawsuits and legislative wrangling involving representatives from the Iron Range.
Stine said it will be late this year or next year before the ongoing study is resolved to the point where MPCA can propose discharge rules. Part of the process will include a peer review of the existing research and more study to identify which waters in the state qualify for sulfate protection.
“We have questions and there will be lots of different views,” Stine said.