A hearing by the Minnesota Public Utilities Commission heard testimony from residents and agency staff this week, and indicated that it was going to take its time in setting statewide wind farm siting guidelines.  “I think there are a lot of remaining unanswered questions. I think there are a lot of … substantive questions as well,” Commissioner Phyllis Reha said. “I think the commission has a lot of work to do before we make any kinds of decisions.”

Monday’s hearing focused on a report issued last year by the Minnesota Department of Health outlining the potential health impacts from wind turbine noise. The PUC and its staff requested health department officials review scientific literature after people statewide raised concerns regarding wind projects.

In the scientific report, state health officials – drawing from National Research Council findings – noted that noise from wind turbines “generally is not a major concern for humans beyond a half-mile or so.”  Nonetheless, the report and PUC staff recommended that setbacks be increased only to 1000 feet; current regulations set a 500 foot minimum, but the night time noise limit of 50dB means that in practice, most turbines are sited at least 700-1200 feet from homes.

Some groups – including Goodhue County residents – have advocated setbacks of six-tenths of a mile or even 1.25 miles to prevent possible health effects, a point PUC staff and others say is supported by “scant” evidence. Still, Commissioner J. Dennis O’Brien said, “We know these issues are strong and heartfelt … and genuine and real. We’ll just have to struggle with it for a while, I think.”