Expert Witnesses Concerned About Wind Farm Noise Pollution

 The McLean County Zoning Board of Appeals deliberates on testimony heard Thursday night. (Image credit: Matt Johnson)

The McLean County Zoning Board of Appeals deliberates on testimony heard Thursday night. (Image credit: Matt Johnson)

The McLean County Zoning Board of Appeals (ZBA) continued to hear testimony Thursday night on the proposed 58-turbine Bright Stalk Wind Farm.

On Tuesday and Wednesday, EDP Renewables continued to present expert witnesses on noise, property values and decommissioning plans with its representatives resting their case Wednesday night.

Earlier this week, EDP Renewables presented Rhett Good, a wildlife expert, who was asked about the effects of turbine noise on certain bird species. Good responding by saying that studies had only looked a mortality rates and not other types of disturbances.

Brian Armstrong, who represents the opponents of the Bright Stalk Wind Farm, began presenting his witnesses Wednesday.

Paul Schomer testified as an expert witness in acoustics and sound measurement. Schomer is a consultant with Schomer & Associates, Inc., a consulting firm in acoustics and noise control. Schomer said the EDP Renewables acoustic modeling tested the average wind speeds the turbines would face at full production, 24 hours a day.

The Illinois Pollution Control Board (IPCB) regulations, which Schomer helped develop, test to a maximum limit. A model focused on the averages would allow some turbines to exceed the limit while others would fall below. As a result, EDP Renewables would not be in compliance with the IPCB, Schomer said.  

Jerry Punch, Professor Emeritus in Communication Sciences and Disorders at Michigan State University, testified as an expert in audiology and health effects, but not as a medical professional.

A noise level above 40 dBA, a weighted decibel level measurement, could cause high annoyance to residents, Punch said. He found several of the proposed turbines to exceed this limit. Over the years, Punch has studied wind farms and the noise annoyance to local residents. He has seen some residents who are more sensitive move from the area.

EDP Renewables asked if annoyances could be developed from more than one stress factor and particular circumstances. Both experts agreed this could be the case.

What’s next?

The ZBA will meet on Tuesday, February 27, at 6:00 p.m. in the Government Center, Room 400 in Bloomington where hearings are set to continue. A decision will be made after all of the hearings conclude.