The El Paso County Board of County Commissioners has new information to consider about the Golden West Wind Energy Center in Calhan, Colorado, following their regular meeting March 23. The wind energy center is owned by NextEra Energy Resources, who presented information on the project, including data about shadow flicker, infrasound and electromagnetic fields.
The wind energy center, which has been fully operational since October 2015, consists of 145 453-foot tall industrial wind turbines, connected to an electrical substation in Falcon by 29 miles of overhead transmission lines.
Since then, residents in the vicinity of the wind energy center have reported negative physical and psychological effects they attribute to the turbines, which range from decreased body temperature, headaches, dizziness, nausea and sleep disturbances.
Richard Lampeter, an associate with Epsilon Associates Inc., an environmental engineering and consulting firm in Maynard, Massachusetts, presented data on behalf of NextEra on the shadow flicker cast by the individual turbine blades as they rotate.
Lampeter said during the project’s approval process, certain conditions had to be met, most notably that a 30-hour-per-year threshold of shadow flicker was the highest amount any one residence could experience. The threshold is a German guideline, based on a German court case, that has become an industry standard, he said.
“To calculate the hours-per-year, we used the industry-standard WindPRO software package,” Lampeter said. Certain calculations, such as the location of the wind turbines, wind turbine dimensions and calculation area are then input into the software, with adjustments for wind direction, wind speed and sunshine probabilities, he said. In all, two homes where residents have signed leasing contracts with NextEra, which are called participating homes, are impacted at that 30-hour threshold, Lampeter said. The maximum number of hours any home where residents have not signed a contract with NextEra, called non-participating homes, experience is 24 hours and 34 minutes; according to the software, he said.
“The project is in compliance based on this modeling software,” Lampeter said.
Chris Ollson, owner and senior environmental health scientist with Ollson Environmental Health Management in Toronto, Canada, also presented research on behalf of NextEra on shadow flicker in wind energy centers. He said he has heard a concern that shadow flicker can cause seizures, which is not accurate. “The shadow flicker is not a health concern,” he said. “It does not induce seizures because the turbines simply do not rotate fast enough.”
Ollson said his information is from Canadian government sources, and the Golden West Wind Energy Center should not result in any adverse effects on health.
Lampeter also presented information on Epsilon’s sound level evaluation, which they measured at 15 different locations throughout the wind energy center. At those locations, the turbines were audible. If necessary, Epsilon would subtract the ambient sound level from the operational sound level to obtain a wind-turbine-only sound pressure level and then compare that to the limit, according to his presentation.
“We tried to measure the noise at the worst-case scenario conditions,” Lampeter said. The goal was to see how noisy the turbines could potentially be during operation, he said. The county’s permitting requirements state that the turbines must not exceed 50 A-weighted decibels, the level at which a noise is considered “acceptable,” Lampeter said. The results of the sound study indicated that all 15 locations met the 50-dbA limit, he said.
As part of Ollson’s presentation, he cited a study by Health Canada in 2014 titled “Wind Turbine Noise and Health Study,” which he said is the largest study in which objective measures of health were observed. More than 1,200 people participated, and the overall conclusion from the study found no evidence of an association between exposure to industrial wind turbines and the health status of the participants, beyond an “annoyance,” Ollson said. This included effects from infrasound, he said.
Commissioner Mark Waller asked if the effects from the infrasound could compound over time to cause health issues, and Ollson said, “No. We are under the threshold where you would experience health impacts.”
Following the presentations, citizens who attended the meeting were given the opportunity to comment. Sandy Wolfe, a former resident who moved from her home in the wind energy center’s footprint, said no one has answers for why she and her husband were getting sick, if what Ollson and Lampeter presented was accurate.
Wolfe’s husband, Jeff Wolfe, also commented, and said he has physical evidence to support his claims that he is getting sick from the turbines. “My hair samples showed cortisol levels that were five times higher than normal,” he said. “My body temperature was down in the 95-degree range before I left. I had to leave my house (near the wind energy center) and take a job across the state to get away from them.”
Robert Rand, an acoustician from Boulder, Colorado, supplied the BOCC with a copy of a professional review of the sound study conducted by Epsilon and submitted to the county in October 2016. In his review, Rand cited 12 instances where the study contained either errors or omissions.
For example, Rand’s review states, "The Epsilon Report does not assess for noise disturbance, despite apparent neighbor complaints of noise disturbance. Noise disturbance is prohibited by the County Ordinance No. 02-1, Section 3(e) and Section 4(a).”
“My professional experience says this facility should not have been permitted with turbines this large and this close to non-participating residential properties,” Rand’s report states. “The Epsilon Report shows the noise levels do not always comply with law and are consistent with noise disturbance. The law, were it enforced, requires the facility noise levels to be reduced.”
Additional sound study
In a separate interview with The New Falcon Herald, Joe Cobb, another resident living near the turbines, said he and two other couples hired Rand to conduct his own infrasound study, the results of which were provided to the BOCC and the NFH prior to the meeting. In the report dated Jan. 29, 2016, Rand analyzed data collected from three homes during December 2015 and January 2016, totaling about 30.5 million samples of acoustic pressure measurements.
Rand’s study states that the analysis, while far from complete, suggests that there is “a condition of noise disturbance due to very low frequency acoustic pressure oscillations in the vicinity of the Golden West Wind Facility when it is operating, with more severe impacts downwind.”
Complaint resolution process
According to the development agreement between EPC and NextEra, residents can lodge complaints regarding shadow flicker, noise and traffic; although there is a specific complaint resolution process they must follow.
John Dailey, business manager with NextEra, said about 83 complaints were received between March 2015 and the meeting date. “Approximately 85 percent of the complaints were received during the seven-month construction period,” he said. “The remaining 15 percent of complaints have been received in the approximately 17 months since construction ended.”
Waller asked if any complaints had been made regarding the health of people or their animals. Dailey said about four or five people have lodged such complaints, and some have done so multiple times.
Cobb said both he and his wife have filed complaints with NextEra, and nothing has been done or sent to the county to continue the complaint resolution process. “How much time do they need to resolve these issues?” he asked. “They are professionals, and they need to stick to the agreement they made with the county.”
Craig Dossey, executive director of the EPC development services department, said no issues have been elevated to the county to handle through the resolution process at this time.
Regarding the noise and shadow flicker issues, Dailey said, “We want to take another crack at resolving those complaints before elevating them to the county.”
The commissioners urged residents to continue to use the complaint resolution process, and agreed that a future meeting regarding the wind energy center would be likely.