Maine DEP internal conference call meeting notes: wind turbine noise

These meeting notes detail the thinking of Dr. Dora Mills, State of Maine Public Health Director and Staff of the Maine Department of Environmental Protection regarding wind turbine noise. At the time of this meeting, attendee Andrew Fisk of Maine DEP had notified First Wind that their wind facility in Mars Hill ME was operating in compliance with the permit he had issued. Dr. Mills was preparing to present information on turbine noise before the Maine Medical Association meeting later in the month. All attendees were discussing how to proceed with two other wind projects proposed in the State. Both proposed projects use RSE to model the preconstruction noise levels.


  1. Dr. Dora Mills - State of Maine Public Health Director
  2. Andrew Fisk - Director of the Bureau of Land & Water Quality at the Maine Department of Environmental Protection
  3. Warren Brown - EnRad Consulting. Hired by Maine DEP to review and validate post-construction noise surveys of the Mars Hill wind energy facility conducted by the developer, First Wind.
  4. Beth Callahan - Project Coordinator Maine DEP
  5. Jim Cassida - Licensing coordinator Maine DEP
  6. Becky Maddox - Project Manager, Maine DEP

Warren Brown: 20+ years in Europe - wind turbine noise has been being researched {Denmark, Belgium, Germany}

Regulations adopted over sear by each particular country. In US, slow response to wind turbine noise. Industrial noise started being addressed in 60's - 70‘s but we haven't addressed wind turbine noise yet.

Internet - Wind turbine experts, studies in Europe conclusions drawn - people have access to this info.

Dr. Pierpont - studies in US recently done. Medical research conducted (scientific study)

Science behind wind turbine noise - low frequency energy causes a rumbling.

At unknown distance - get some of that rumbling noise, especially with windows open at night in rural areas. Low Frequency rumble created by turbines.

France took lowest 10% of sound that occurs at night (L-90). Acoustic sound at night can be twice what it is, based on A-weighted sound. France said no to turbines! (Measured at property line.)

Acoustic energy can damage hearing!

Dora Mills: Just because you can hear it doesn't mean it has adverse health effects!

Warren Brown: A-weighted measurements established by OSHA for industrial noise - different altogether than wind turbines.

A-weighted is based around hearing protection!

L-90 allows this to be adjustable to the existing sound level of the area (raises base line up!)

European standards:

UK = 43 dB(A) or L-90+5
Australia = 35 dB(A)

Europe captures lower frequency noise the same as US does.

Maine's rules are very conservative in US - 45 dB(A) in Maine. But as a community we have not taken account for the low-frequency spectrum!
The other countries use dB(A) as well, not dB(C), but Maine needs to think about low-frequency.

Dora Mills:

1) Went through Dr. Pierpont's studies. She says it's not scientific (group of anecdotes does not equal scientific study!)

2) Colorado - DOE studies, noise not related to medical issues.

3) Canada - a couple articles in journals can have annoyances but not necessarily health effects.

4) Europe - Annoyance = adverse health effect (WHO), World Health Organization - studies done in urban areas, not rural!

5) UMASS Amherst - 1995, info from around N.E. (New England). Info in Netherlands = 30-35 dB(A).

6) Maine - looked at standards. Reviewed people's issues in Mars Hill. Are our regs protective enough?

Not a lot of evidence of adverse health effects, even at Mars Hill, but subjective!

Anecdotal issues with noise only!

Mars Hill, Who issues > need to strengthen these.

Andy Fisk - DEP awarded Mars Hill a 5 decibel variance (for 50 dB(A) but we wouldn't do that again.

Warren Brown: 40 dB(A) will still penetrate their houses! (low frequency noise) - noise can get inside and resonate, consequently noise can be louder inside than outside!

Can't regulate inside noise!

Annoyance based on WHO - Warren says not credible. Maine's noise levels based on 10% of population will be annoyed by noise.

Warren has issue with model being used. Currently it's based on industrial noise, not wind turbine noise! We haven't been able to determine that this model is accurate for wind turbines.

Dora Mills: Maine Medical Association Meeting coming up. Lewiston Sun Journal needs answers.

Angus King will speak at the meeting as well.

We are moving forward with mistakes made at Mars Hill (variance, siting).

WHO issue - Many decades of experience in Europe. Their standards are close to what ours are (measured in dB(A)!)

Warren Brown: Lots of studies done in Denmark/Netherlands - show annoyance is an issue!

Dora Mills: States there is no evidence for state-wide moratorium! Lots of health benefits to wind turbines.

WHO issue - many years of experience with wind turbines. No evidence of adverse health effects!

Andy Fisk: Mars Hill issue - we have learned a bit from this point and will not allow variance, have changed siting etc.

Warren Brown: Reviews are ready to send out. Based on models - in compliance with predictive model for 45 dB(A) nighttime noise, but still questions regarding the model!! Based on industrial noise.

1990 _____ paper done for NASA on nighttime noise based on point science but turbines are not point sources or line sources. They are in between!

Stable atmospheric conditions: Wind speed is stratified as change elevation - may vary a lot causing air turbulence and swooshing and popping noise.
Wind turbine noise needs more investigation!

1. Need to be able to predict stable atmospheric conditions.
2. Setup protocol for acoustic measurements with DEP staff member on-site.
May be able to get ready within month or so but not sure at this moment.

Questioning RSE [noise consultant for wind developer, First Wind] assumptions due to the model!

He's convinced that we can use dB(A)! and don't need to use dB(C).


Editor's note: A complete copy of the original, handwritten notes can be accessed by clicking on the link below.

Maine Dep Conf Call030509

Download file (553 KB) pdf

MAR 5 2009
back to top