Transcription

1

2

3

4

5

6 M E M O R A N D U M To: Martha Staskus From: Eddie Duncan, INCE Bd. Cert. Subject: Georgia Mountain Community Wind Winter Sound Compliance Monitoring Brief Date: April 26, 2013 Winter sound compliance monitoring has been completed for Georgia Mountain Community Wind (the Project ) and the monitoring data has been analyzed. The monitoring was conducted in accordance with the Post-construction Sound Monitoring Protocol: Georgia Mountain Community Wind dated January 2, 2013 (the Protocol ). The Protocol specifies that, monitoring will take place over at least ten days, in each of the summer, winter, spring, and fall during the first full year of operation. A full report is scheduled to be issued at the end of the first full year of operation. At the request of the Project, this memo provides a brief summary of the winter phase of the monitoring procedures and results. MONITOR SETUP Monitoring was conducted at three locations shown in Figure 1: 6Ted Road, 40 FitzGerald Place, and 1179 Georgia Mountain Road. All three monitors were installed and commenced data logging on February 12, The monitor at Ted Road ran to March 3 for a total of 19 days. The monitor at 40 FitzGerald Place gathered data until March 7 for a total of 23 days. And the monitor at 1179 Moscow Road operated until March 8 for a total of 24 days. The monitoring period contained a variety of winter weather conditions. Each monitoring setup included a CESVA SC310 ANSI Type 1 sound level meter with a digital audio recorder, and a separate data logger with an anemometer input to gather wind speed at microphone height. The meter was calibrated before the monitoring period, at weekly checkups during the monitoring period, and then again at the end of the monitoring period. Each microphone was fitted with a seven-inch water resistant wind screen. Each sound level meter logged 1/3 octave band equivalent sound levels (Leq) at 1-second intervals. METHODOLOGY During the monitoring period, the Project was scheduled to curtail the operation of all four turbines each day at four half-hour periods to allow measurement of the background sound levels. RSG conducted a detailed analysis of the monitored data before, after, and during each curtailment period. For each period, the background sound level measured during the curtailment was subtracted from the one-hour periods before and after the curtailment period to test compliance with the 45 dba (Leq 1-hour) exterior sound level limit. 55 Railroad Row White River Junction, Vermont TEL FAX

7 Georgia Mountain Community Wind Resource Systems Group, Inc. Winter Sound Compliance Monitoring Brief April 26, 2013 page 2 Spectra from the curtailment analysis were analyzed in accordance with ANSI S12.0 part 3 tonality s definition, to determine the existence of any tones. First the background sound level spectra as measured during the curtailment periods were subtracted from the operational spectra from the one-hour periods before and after the curtailment to see if any prominent discrete tones were potentially due to turbine operations. If a potential prominent discrete tone was identified from the turbine-only 1 spectra, ANSI 12.0 Part 3 was then applied to background plus turbine spectra to see if the tone was still a prominent discrete tone or if it was masked by the background sound. RESULTS SUMMARY The sound levels due to operation of the Project were less than the 45 dba (Leq 1-hour) exterior sound level limit at each location for the winter monitoring period. There were also no prominent discrete tones at any of the monitors due to operation of the Project. NEXT STEPS Spring monitoring is scheduled to begin in mid-may. The three participating landowners will be contacted again prior to commencing the spring monitoring phase. 1 The existing soundscape at each monitoring location is composed of sound from the wind turbines and background sounds from other sources. Sound levels measured during the curtailment periods represent the background sound level. Sound levels measured at all other times when the turbines are operating represent the background plus turbine sound level. In order to calculate the sound level due only to the turbines, we must subtract the background sound level from the background plus turbine sound level to get the turbine-only sound level.

8 Georgia Mountain Community Wind Resource Systems Group, Inc. Winter Sound Compliance Monitoring Brief April 26, 2013 page 3 Figure 1: Map of Monitoring Locations

9 M E M O R A N D U M To: Martha Staskus From: David-Michael Lozupone, E.I.T. Subject: Georgia Mountain Community Wind Spring Sound Compliance Monitoring Brief Date: July 18, 2013 Spring sound compliance monitoring has been completed for Georgia Mountain Community Wind (the Project ) and the monitoring data has been analyzed. The monitoring was conducted in accordance with the Post-construction Sound Monitoring Protocol: Georgia Mountain Community Wind dated January 2, 2013 (the Protocol ). The Protocol specifies that, monitoring will take place over at least ten days, in each of the summer, winter, spring, and fall during the first full year of operation. A full report is scheduled to be issued at the end of the first full year of operation. At the request of the Project, this memo provides a brief summary of the spring phase of the monitoring procedures and results. MONITOR SETUP As in the winter, monitoring was conducted at the three locations shown in Figure 1: 6 Ted Road, 40 Fitzgerald Place, and 1179 Georgia Mountain Road. In addition, at the request of GMCW an additional monitor was added at 1198 Georgia Mountain Road, in response to the residents request. All monitors logged data from May 29 to June 25, 2013 with the exception of the new monitor which started logging sound pressure levels on June 5, The monitoring period contained rain and a variety of other spring weather conditions. Each monitoring setup included a CESVA SC310 or Larson Davis 831 ANSI Type 1 sound level meter with a digital audio recorder, and an anemometer to gather wind speed at microphone height. Each meter was calibrated before installation, at each weekly checkups, and at the end of the monitoring period. Each microphone was fitted with a seven inch wind screen, or Larson Davis environmental shroud and wind screen. The monitors were set to log 1/3 octave band equivalent (Leq) sound pressure levels at 1-second intervals. METHODOLOGY During the monitoring period the Project shut down all four turbines for 30 minutes on six occasions. The night time periods were selected to cover a variety of meteorological conditions and when the sound power of the turbines were within 1 db of their maximum. RSG conducted a detailed analysis of the monitored data before, after, and during each curtailment period. For each period, the background sound level measured during the curtailment was subtracted from the one-hour periods 55 Railroad Row White River Junction, Vermont TEL FAX

10 Georgia Mountain Community Wind Resource Systems Group, Inc. Spring Sound Compliance Monitoring Brief July 18, 2013 page 2 before and after the curtailment period to test compliance with the 45 dba (Leq 1-hour) exterior sound level limit. Spectra from the curtailment analysis were analyzed in accordance with ANSI S12.0 part 3 tonality s definition, to determine the existence of any tones. First the background sound level spectra as measured during the curtailment periods were subtracted from the operational spectra from the one-hour periods before and after the curtailment to see if any prominent discrete tones were potentially due to turbine operations. If a potential prominent discrete tone was identified from the turbine-only 1 spectra, ANSI 12.0 Part 3 was then applied to background plus turbine spectra to see if the tone was still a prominent discrete tone or if it was masked by the background sound. RESULTS SUMMARY The sound levels due to operation of the Project were less than the 45 dba (Leq 1-hour) exterior sound level limit at each location for the spring monitoring period. There were also no prominent discrete tones at any of the monitors due to operation of the Project. NEXT STEPS Summer monitoring is scheduled to begin in August. The three participating landowners will be contacted again prior to commencing the spring monitoring phase. 1 The existing soundscape at each monitoring location is composed of sound from the wind turbines and background sounds from other sources. Sound levels measured during the curtailment periods represent the background sound level. Sound levels measured at all other times when the turbines are operating represent the background plus turbine sound level. In order to calculate the sound level due only to the turbines, we must subtract the background sound level from the background plus turbine sound level to get the turbine-only sound level.

11 Georgia Mountain Community Wind Resource Systems Group, Inc. Spring Sound Compliance Monitoring Brief July 18, 2013 page 3 Figure 1: Map of Monitoring Locations

12 M E M O R A N D U M To: Martha Staskus From: David-Michael Lozupone, E.I.T. Subject: Georgia Mountain Community Wind Summer Sound Compliance Monitoring Brief Date: October 4, 2013 Summer sound compliance monitoring has been completed for Georgia Mountain Community Wind (the Project ) and the monitoring data has been analyzed. The monitoring was conducted in accordance with the Post-construction Sound Monitoring Protocol: Georgia Mountain Community Wind dated January 2, 2013 (the Protocol ). The Protocol specifies that, for three required locations, monitoring will take place over at least ten days, in each of the summer, winter, spring, and fall during the first full year of operation. A full report is scheduled to be issued at the end of the first full year of operation. At the request of the Project, this memo provides a brief summary of the summer phase of the monitoring procedures and results. MONITOR SETUP As in the previous seasons, monitoring was conducted at the three required locations shown in Figure 1: 6 Ted Road, 40 Fitzgerald Place, and 1179 Georgia Mountain Road. Additionally, an auxiliary monitor was added at 1198 Georgia Mountain Road. Each primary monitor logged data from August 30, 2013 to September 13, The auxiliary monitor at 1198 Georgia Mountain Road monitor ran for two days of the two week monitoring period, from September 5, 2013 to September 7, 2013, and captured data for five of the eight curtailments periods. The two-week monitoring period contained a variety of summer weather conditions, including clear and rainy periods, and low and high winds, etc.. Each monitoring setup included a CESVA SC310 or Larson Davis 831 ANSI Type 1 sound level meter with a digital audio recorder, and an anemometer to gather wind speed at microphone height. Each meter was calibrated before installation, at each weekly checkup, and at the end of the monitoring period. Each microphone was fitted with a seven inch wind screen, or Larson Davis environmental shroud and wind screen. The monitors were set to log 1/3 octave band equivalent (Leq) sound pressure levels at 1-second intervals. METHODOLOGY During the monitoring period the Project shut down all four turbines for 30 minutes on eight occasions. The night time periods were selected to cover a variety of meteorological conditions and 55 Railroad Row White River Junction, Vermont TEL FAX

13 Georgia Mountain Community Wind Resource Systems Group, Inc. Summer Sound Compliance Monitoring Brief October 4, 2013 page 2 when the sound power of the turbines were within 1 db of their maximum. RSG conducted a detailed analysis of the monitored data before, after, and during each curtailment period. For each period, the background sound level measured during the curtailment was subtracted from the one-hour periods before and after the curtailment period to test compliance with the 45 dba (Leq 1-hour) exterior sound level limit. Spectra from the curtailment analysis were analyzed in accordance with ANSI 12.9 Part 4 tonality s definition, to determine the existence of any tones. First the background sound level spectra as measured during the shutdown periods were subtracted from the operational spectra from the one-hour periods before and after the shutdown to see if any prominent discrete tones were potentially due to turbine operations (turbine only spectra). This was useful for filtering out tonal periods due to insects, birds, and other non-turbine sources. If a potential prominent discrete tone was identified from the turbine-only spectra, ANSI 12.9 Part 4 was then applied to the raw spectra from the primary monitor. Any resulting prominent discrete tones were then reported. RESULTS SUMMARY The sound levels due to operation of the Project were less than the 45 dba (Leq 1-hour) exterior sound level limit at each location for the summer monitoring period. There were also no prominent discrete tones at any of the monitors due to operation of the Project. NEXT STEPS Fall monitoring is scheduled to begin in either late October or early/mid-november. The three participating landowners will be contacted again prior to commencing the fall monitoring phase.

14 Georgia Mountain Community Wind Resource Systems Group, Inc. Summer Sound Compliance Monitoring Brief October 4, 2013 page 3 Figure 1: Map of Monitoring Locations

15 M E M O R A N D U M To: From: Subject: Martha Staskus Eddie Duncan, INCE Bd. Cert. Georgia Mountain Community Wind Response to Public Service Board Memo Dated , Re: Complaint of Reggie Johnson and Shirley Phillips Date: October 8, 2013 CC: Andy Raubvogel, Esq. This memo is in response to the complaint filed by Reggie Johnson and Shirley Phillips (Complainants) on September 18, In the letter filed with the Public Service Board, the Complainants claim that Georgia Mountain Community Wind (GMCW) violate their Certificate of Public Good (CPG) by generating discrete tones. Their claim is specific to fans located at the base of the turbines, and they provided Exhibit A to back the claim that the project generates discrete tones. Their Exhibit A is a letter to Annette Smith of Vermonters for a Clean Environment from Rick James, of E-Coustic Solutions. In the letter, Mr. James describes an analysis he conducted on the audio signal of video footage of the fans operating at the base of a wind turbine at GMCW. From the text and pictures, it appears that the video was taken of the cooling units themselves, which means that the video camera was located somewhere relatively close to the turbines, as the cooling units are not visible from any of the residences. Mr. James extracted the audio from the video and analyzed the audio using SpectraPlus software to determine if there were tones. Through this analysis, he concludes that there are three distinct sounds and that there is a problem, and discrete tones are being generated. The analysis methodology used by Mr. James, and the methodology of recording the audio, via video camera near to the turbines, does not conform to those that are established in the Postconstruction Sound Monitoring Protocol: Georgia Mountain Community Wind dated January 2, 2013 (the Protocol ), and therefore, cannot be relied upon. Among the many issues is that their Exhibit A appears to be based on measurements near to the cooling units and not at the residences. Neither the information provided by Mr. James nor the Complainants provide a sufficient basis to conclude the project is in violation of the prominent discrete tone clause in the CPG. 55 Railroad Row White River Junction, Vermont TEL FAX

16 Response to Johnson and Phillips complaint to Resource Systems Group, Inc. the Vermont Public Service Board 8 October, 2013 page 2 RSG has conducted sound monitoring during the winter, spring, and summer of this year in accordance with the Protocol. Sound monitors were set up over at least 10 days during each of those seasons at the required residential locations to the north, west, and south of the facility. RSG conducted a detailed analysis of the monitored data before, after, and during each required curtailment periods. For each period, the background sound level measured during the curtailment was subtracted from the one-hour periods before and after the curtailment period to test compliance with the 45 dba (Leq 1-hour) exterior sound level limit. Spectra from the curtailment analysis were analyzed in accordance with ANSI 12.9 Part 4 tonality s definition, to determine the existence of any tones. First the background sound level spectra as measured during the shutdown periods were subtracted from the operational spectra from the one-hour periods before and after the shutdown to see if any prominent discrete tones were potentially due to turbine operations (turbine-only spectra). This was useful for filtering out tonal periods due to insects, birds, and other non-turbine sources. If a potential prominent discrete tone was identified from the turbine-only spectra, ANSI 12.9 Part 4 was then applied to the raw spectra. With the three quarters of sound monitoring completed, we have found all periods at all locations below 45 dba(leq 1-hour) exterior and with no prominent discrete tones. A full report of these results will be completed after the last required quarter of sound monitoring this fall.