State reviews how to measure groundwater contaminants

The Minnesota Department of Health will present updated rules to evaluate contaminants in groundwater and their health risks before an administrative law judge this Friday.

Samuel Yamin is a toxicologist and health risk assessor with the Minnesota Center for Environmental Advocacy.

He said the updated rules are less protective of public health than the department originally recommended in 2004. The number of chemicals included have also gone down from 80 to 22.

"Our concern is the end product. What kind of guidance are we getting from our health agency on how much of these chemicals -- what quantity -- is safe in drinking water? And we see that getting weaker. We see the number of chemicals, where we're getting good new guidance, has dwindled to just a handful now," Yamin said.

John Linc Stine with the Minnesota Department of Health said the agency has adjusted chemical values based on current scientific research.

"I wouldn't interpret it -- the updated rule -- as weaker or stronger. There are numbers that have gone up and there are numbers that will go down in this proposed rule, but that's because the understanding has improved both of the risk and the exposure, and the way to calculate the risk," Stine said.

Stine said the department is prioritizing the chemicals, starting with 22, and then working its way down the list. Stine says the rules have not been updated since 1994.