HomeMy WebLinkAbout2010-03-02-NAC-min
NOISE ADVISORY COMMITTEE
MINUTES
2 March 2010 Meeting
A duly posted meeting of the Noise Advisory Committee (NAC), held in the Legion
Room, Cary Hall, was called to order at 7:30 PM by Chairman Tony Galaitsis with
members Jeanne Krieger, Martha Wood, Steve Kropper, Bob Earsy, Jack Maloney
present. Present in the audience were Lexington Building Commissioner Mr. Garry
Rhodes, six Shire representatives, and five Shade St. residents.
The meeting had been convened at the request of Mr. Garry Rhodes, who was tasked by
the Zoning Board of Appeals (ZBA) to seek procedures for addressing the noise issues
related to section I of Shire’s SDUP and associated noise concerns expressed by Shade St
residents.
Mr. Rhodes reported that the ZBA has not taken a vote yet, and that the ZBA chairman
requested assistance from NAC in the following areas:
1) Help establish the “ambient noise level” around the Shire property
2) Estimate the noise level when Raytheon occupied the site
3) Current situation and remediation under discussion regarding Building 300
4) Review whether Shire’s proposed methods for determining noise levels are reasonable
Discussion by NAC members
Ms. Krieger asked why a Raytheon-time noise level is relevant. Related questions were
about whether the past “Raytheon noise level” referred to a) a condition with the
Raytheon equipment operating, or b) a condition with the Raytheon equipment not
operating (ambient). Mr. Raymond Buckley, attorney for Shire, indicated that his team
knew the equipment used by Raytheon and could use a model to estimate Raytheon-time
noise levels.
Further discussion between NAC members established that the important and relevant
quantities are the:
The Equipment noise at residences with the Shire equipment ON
The Ambient noise at residences with the Shire equipment OFF
Consequently, any reference to the Raytheon-time noise was deemed irrelevant. Mr.
Buckley agreed that this conclusion was also consistent with Shire’s position.
Mr. Galaitsis asked whether anyone was concerned about daytime noise or solely about
nighttime noise. Both nearby residents and Shire representatives agreed that only
nighttime noise was an issue. Subsequently, Mr. Galaitsis asked what season would be
used to establish the Shire Equipment noise levels (with equipment ON) and the ambient
noise level (with equipment OFF). Shire proposed wintertime measurements stating that
noise levels are highest when there is no foliage; citizen representatives preferred
summertime measurements stating that noise levels are highest when windows are open
at night. Mr. Earsy suggested a summertime measurement around 2:00 AM.
Mr. Kropper asked if Equipment noise levels varied by time of day. A Shire
representative suggested that HVAC operations did not vary with time of day or
occupancy, but varied with environmental conditions, i.e., depending on the need for
cooling versus heating.
Citizen Comments
Jeannie Canale, 29 Shade Street, commented that noise levels have gone up and their
tones shifted since the installation of certain roof top equipment. A Shire representative
responded that the installation of noise mitigation equipment is only partially completed.
Michelle Ciccolo, 50 Shade Street, indicated that noise measured on Shire’s property line
is less important than noise measured at residences, where it disturbs people. She
suggested that some of the noise monitors proposed for Shire property line locations be
placed at locations within nearby residential properties. Perhaps monitoring eight homes
would be representative. Perhaps four houses would be sufficient. Mr. Galaitsis suggested
that Shire representatives meet with Shade St. neighbors to select some mutually
agreeable residential locations for some of the noise monitors. Both Shire representatives
and residents agreed to do so.
Mrs. Vicki Blier, 41 Shade St., inquired about the definition of a property line. A Shire
representative opined that property line was a vertical plane from the line skyward.
Shire Acoustics Consultant Comments
Mike Bahtiarian, of Noise Control Engineering and consultant to Shire, briefed the NAC
on a new 10-days old plan to address the noise problem. Copies of plan were distributed
to members. The NAC was asked to review this plan in conjunction with the March 2,
2010 Shire HGT Ambient Sound Level Assessment Measurement Protocols (DRAFT).
All proposed measurements would be conducted at ground level even though noise level
may vary with height.
Discussion ensued about proper design of a test to ascertain ambient noise levels
including placement and count of microphones. Mr. Bahtiarian stated that the Shire team
would measure octave-band and 1/3-octave-band levels at various locations with most of
the Shire equipment off and some of the equipment on. He stated that another acoustics
firm (Acentech from Cambridge) would model the buildings and the noise sources to
calculate and subtract the active equipment noise out of the measured noise.
Detailed discussion on pros and cons of plan ensued. Mr. Galaitsis and Mr. Earsy did not
accept Mr. Bahtiarian’s suggestion to use L as an alternate approach to measuring
EQ
ambient noise. They both stated that L-90 is the appropriate metric. Mr. Galaitsis
expressed concern about the Draft protocol’s modeling accuracy for ambient noise level,
and suggested that the ambient noise level be actually measured with all Shire equipment
shut down.
Mrs. Vickie Blier inquired whether the noise level with the Shire equipment on will set a
new ambient noise level, and whether a future developer could later add another 10 dBA
to that level. The answer was: “No, the ambient noise level will always correspond to a
condition with all present and future equipment off.” Mrs. Bleier then said that if the
summer ambient noise is only 20 dBA, then the maximum allowed noise should be set
relative to that. On the other hand, if the winter ambient is lower, winter may be a better
time to measure the ambient.
Next Step
Mr. Galaitsis inquired about Shire’s schedule seeking to ensure that the NAC has
adequate time to review the remaining information in time to provide comments to the
ZBA. A Shire representative indicated that a revised proposal would be distributed to the
NAC members before the next NAC meeting. Mr. Galaitsis requested that any new
information be submitted to the NAC on Thursday before the (Tuesday) meeting to allow
enough time for technical review.
The NAC meeting was adjourned at 9:15 PM
Minutes prepared by Steve Kropper, Acting Secretary