HomeMy WebLinkAbout1998-11-19 Noise Survey SPR Acentee'd lacorporaled '1'r ',00e 617.490-8000
33 Moulton Street h .file 617-409.8074 i
cambrldge,1ir1021:38 E-mail:postbo0zacenteclr.com
July 15, 1998 Acent '"' "
1948 • 1998 50 Years of Consulting Excellence
Mr. John Schroeder
Mesiti Development
11 Old Boston Road
Tewksbury, MA 01876
Subject: Site Noise Survey
Northeast of the Junction of Route 125 and Hillside Road
North Andover, MA
Acentech Project No. 613777
Dear Mr. Schoeder:
At your request, we conducted a site noise survey at the property located northeast of the
junction of Route 125 (Andover Bypass) and Hillside Road in North Andover, MA. This letter
summarizes our measurements.
Observations
As described above, the site is located adjacent to Route 125 and is shown in Figure#l. The
major noise source that exists at the site is the heavy volume of traffic on the Andover Bypass.
During my visit on the afternoon of the July 1P, the traffic consisted mainly of cars, but there
was also a small percentage of trucks and motorcycles that passed the site. Aircraft overflights
and residential activity (lawn mowing and yard work) were the only other discernible noises that
were observed during the visit. There were no audible mechanical noise sources or commercial
activity(such as truck deliveries or loading dock activity) at this time,
Applicable Criteria
The Environmental Affairs Office of the Commonwealth of Massachusetts has defined the
ambient noise level as the background A-weighted sound level that is exceeded 90% of the time
measured during equipment operating hours. Furthermore, it states that any source of noise is in
violation of the Air Quality Control Policy, if the broadband sound level is increased by more
than 10 dBA above ambient, or if there is a condition of a "pure tone". A"pure tone" is defined
as any octave band center frequency sound pressure level exceeding the two adjacent center
frequency sound pressure levels by 3 dBA or more.
Measurements
For this site noise survey,we performed two sets of measurements. The first involved a
handheld spectrum analyzer,which was used to record 15 second readings of the noise level in
the afternoon. The ambient(L90) noise level was pleasured to be about 49 dBA. A frequency
plot of the Lgo noise level is shown in Figure#2.
Audiovisual and Sound System Design Noise and Vibration Coulrot Archilectural Acoustics h'iiutrownentaI and indulrial Acoustics
1 }
Mr. John Schoeder
July 15, 1998
Page 2
The second set of measurements was obtained with a continuous monitor that was left at the site
for a time period of nearly 24 hours, starting at about 4:18 PM on July 13`h and ending at about
4:15 PM on July 14`h. This monitor was set up to record the sound pressure levels 32 times each
second and make statistical calculations of this data over the course of 5 minutes. The ambient
noise levels {L90} varied between about 35 dBA in the early morning hours to about bl dBA at
the peak of the morning commuting Hours. The ambient noise levels during the daytime hours
were typically between about 47 dBA and 52 dBA, while nighttime ambient levels dropped to
less than 40 dBA. Figure #3 is a plot of the L.90 noise levels recorded over the duration of the
measurement.
Summary
The results of the measurements show consistency between the two methods, with a daytime
ambient noise level of about 47 to 52 dBA. Evening ambient noise levels gradually dropped
from the daytime levels to about 40 dBA with nighttime noise levels being measured between
about 36 and 40 dBA.
We hope this provides you with the information that is necessary at this time. If you have
questions, please feel free to contact me at 617-499-8058,
Sincerely yours,
ACENTECH INCORPORATED
Jeffrey L. Fullerton
Consultant
encl. Figure#1, #2, and#3
j:\b 1377 TWesiti jIf--I Aw
ceteVI IJ
j
Mr, John Schoeder
July 15, 1998
Page 3
300ft
114 ,
APPROXIMATE
SITE LOCATION
" MEASUREMENT
LOCATION
r r
01997 GaoSystvrr Global Carp,;01997 IlauTech
Figure#1
Centech
k � r
Site Noise Measurements
Junction Route 125 and Hillside Rd
North Andover, MA July 13, 1998
90
80 - -- - - - -'-- - -_ -4 - --- - -- - - -- - - - --- - -- ---- - - - ----- -- ---- -
i 1 1 1
--X--L90 (15 Seconds)
70 ;-- --- - - =-- - ----k- ------- ---- - - - ------- - - - --- - -
� I
E60 --- -- - - - - - - -- - - --- ------- ' ----- --;------ --- - - --
0
N
L [
50 - -- -- -- - ----- - - _ --- - ___ _ - - -- -
a
0
30 ---- - - - - - - - - - --- -- - ---
� � I
20 ---- - --- -' - ------ --------' ------- --- -- - - ------ --- - - -- ' ,
1 I I !
I . �
I !
I
I I
I 1 I
e I [ [
10 '
31.5 63 125 250 500 1000 2000 4000 8000 dBA
Octave Band Center Frequencies (Hz)
Figure#2 caste&
Sound Pressure Level (dBA re 20mPa)
--* N w P v1 0)
CD O C) O O O C7 O o
4:18 PM
I 1
;
5:15 PM
i I
, f I
, 1 1
6:15 PM
I �
;
;
;
7:15 PM
1 1 �
;
;
8:15 PM ;
1 I I
;
9:15 PM
;
;
;
10:15 PM ;
f 1
;
11:15 PM Z
o
t 1 I I I 1 C-
12:15 AM
D
1:15 AM �. p cr
p
C CD
2:15 AM o
+ o
to Fn'
3:15AMch
w 4:15 AM ,C m
N
CL C
5:15AM
N
I � � Q
6:15 AM -
^� CL
7:15 AM
OD
i
1
8:15 AM '
; 1
9:15 AM
I
;
;
10:15 AM
I
11:15AM
1 1
o
12:15 PM in
;
1
1:15 PM ; c
I • ;
2:15 PM
3
1 ;
;
3:15 PM '
i I
;
;
r