The Minnesota Pollution Control Agency has postponed recommending whether changes are needed to the state's sulfate standard for wild rice, which could eventually lead to new enforcement affecting mining operations, wastewater treatment plants and other industries.
The agency gave no detailed explanation for canceling the release Thursday, which was to include a media briefing and meetings with lawmakers and stakeholders.
"We thought we would be ready to release preliminary findings on the wild rice sulfate standard on Thursday, but we are not," MPCA spokesman Dave Verhasselt wrote in an e-mail to reporters late Wednesday. "We will update you when we can in the coming weeks."
Verhasselt said in an interview that the delay in the recommendations was unrelated to an analysis released by the Minnesota Chamber of Commerce questioning the study for which the MPCA will base its recommendations. He said only that "our ability to have a dialogue is incomplete."
The mining industry, cities, environmentalists and tribal groups are among the stakeholders who have been involved in the process, as well as state lawmakers, who arrived back in St. Paul this week for a short legislative session. Iron Range lawmakers in the past have pushed for legislation that would weaken the standard, but in 2011 lawmakers settled on having the MPCA further study the issue.
That study, released in January, suggests sulfate hurts wild rice when it turns into hydrogen sulfide, reaffirming a link between sulfate and wild rice that led to a 40-year-old state rule that limits sulfate to 10 milligrams/liter in wild rice producing waters. The MPCA recommendations were to say whether agency officials think the standard should go up or down and by how much.
But, just as it has done with past research, the Chamber of Commerce is questioning the new study's methodology and conclusions. The Chamber's 84-page analysis concludes that based on the MPCA's study, a sulfate standard is unnecessary. If the MPCA determines one is needed, the Chamber said a standard of 1,600 milligrams/liter should be adopted for waters that produce wild rice.
The report's release suggests that the Chamber of Commerce, which had previously sued over the issue, will continue to fight to weaken or eliminate the sulfate standard. The group has testified to lawmakers in the past that more than 200 industrial facilities and nearly 400 municipal wastewater treatment plants produce enough sulfates to be covered by the rule.
On the other hand, environmentalists and tribal groups have also fought in court to keep the standard in place and have pushed state regulators to enforce the standard.
The dispute is unlikely to be resolved anytime soon.
John Pastor, a University of Minnesota Duluth researcher and one of the study's lead researchers, said the MPCA has a difficult task because under the right conditions, even low levels of sulfate can convert into the toxic sulfide that kills wild rice.
"It doesn't take much under the right conditions to do it," he said. "The problem is setting a standard that protects things under those right conditions, but at the same time you also have other conditions in which sulfate can go very high."
Pastor said the 10 milligrams/liter standard or something close to it is "about right."
"It's really hard to say what's a single number that works for all conditions. Unfortunately, that's the way the regulatory laws work," he said. "This is a very, very complicated problem."
On Thursday, some of the groups pushing to keep the sulfate standard in place expressed frustration with the MPCA's delay and asked for more clarification.
Also Thursday, the Minnesota Department of Natural Resources announced it would not extend the public comment period for PolyMet's proposed copper-nickel mine. That means it's possible the March 13 deadline for comments on the mine's environmental study could come before the MPCA's sulfate recommendations.
Although PolyMet has said its plans would meet the state's current sulfate standards, some environmental groups had planned to incorporate the MPCA's latest sulfate findings and recommendations in their comments.
MPR News reporter Dan Kraker contributed to this report.