By Ruth Thompson | Wicked Local Scituate | Posted Aug 29, 2013 \ www.wickedlocal.com
Preliminary test results from an acoustical study performed on the Scituate Wind turbine on the night of August 14 and early morning hours of August 15 came back within allowable state limits.
The results were announced during the Scituate Board of Health meeting on Monday (Aug. 26).
The testing done on these nights is just one of four tests Scituate Wind has been contracted to conduct on behalf of the town. The testing is to determine whether noise from the turbine is exceeding noise levels allowed by the state.
Scituate Public Health Director, Jennifer Sullivan, said most background noise was from traffic and insects.
“The difference between the turbine on and off was only a few decibels,” she said.
At Monday night’s board of health meeting, Gordon Deane, president of Palmer Capital Corporation, the manager of Scituate Wind, LLC, submitted two tables showing the results of the testing. Deane explained that MassDEP’s noise regulations allow a 10 dBA maximum increase.
On the first night of testing the maximum increase recorded was 3.9 dBA, he said.
“For most people, one needs a change of sound of 3 dBA to be audible.”
The first table indicates how the Massachusetts Department of Environmental Protection (MassDEP) determines compliance – comparing ambient (background with the turbine off) with measured (turbine on) – the average of the loudest measurements recorded from the turbine.
“While this is an apples to oranges comparison, it’s what MassDEP does,” Deane said, adding that MassDEP’s sampling is currently under review.
A second comparison is “more realistic,” Deane said, because it looks at how much the turbine adds to the background. In these measurements, the table shows the maximum increase was 2.8 dBA.
This past spring the town, along with Palmer Capital Corporation, and the community group comprised of residents living near to the turbine hired separate engineering firms to perform two independent acoustical studies of the turbine.
The community group’s engineer was not able to make it for the first night of testing. A member of the community group did accompany the engineers and Deane during a portion of the testing.
According to information provided with the tables, during the compliance tests, three 5-minute samples were taken with the turbine on, and three 5-minute samples were taken with the turbine off.
The average hub height wind speeds ranged from 8.5 to 12.9 mph, and the average 10-meter wind speeds ranged from zero to 3 mph from the westerly direction based on Marshfield Airport wind data.
The sampling was performed during low tide.
The testing was performed at five locations: 151 Driftway, 56 Moorland Road, and three spots on Gilson Road (Numbers 149, 122 and 127).
Deane said the information collected by Tech Environmental, the company hired by the town to perform the acoustical tests on the wind turbine, has been sent to the community group’s consultant.
“It is hard for me to understand what he will do with it if he was not there and listening to the sounds being generated,” Deane said.
Deane said that during the Aug. 26 board of health meeting, members of the community group “complained that the protocol that they, along with the board of health, participated in drafting, and which was reviewed and approved by the MassDEP, wasn’t appropriate.”
Tom Thompson, the spokesman for the community group, could not be reached for comment by press time.
Scituate Wind has contracted for three more nights of testing and has offered to deviate from the approved protocol if that is what the board of health wants, Deane said.
“Scituate Wind has even offered to have the community group’s consultant pick the next three nights for sampling,” he said.
Deane said Scituate Wind did not receive any direction from the board of health on Monday as to what it wants to do.
“Hence, the current protocol is still operative,” he said.
URL to article: https://www.wind-watch.org/news/2013/08/29/scituate-wind-sounds-of-the-turbine/