4801 Spring Valley Road, Suite 113 Dallas TX 75244 972.934.3700 voice 972.934.3720 fax Wrightson, Johnson, Haddon & Williams, Inc. Designers and Planners for Sound, Video, Multi-Media Telecommunications, Broadcast, Theatre & Acoustics Dallas San Antonio March 17, 2010 Mr. Joe Tilger City of Rowlett P.O. Box 99 Rowlett, TX 75030 VIA Email: [email protected]Original to follow via U.S. Mail pp 64 RE: City of Rowlett – Environmental Noise Assessment Dear Mr. Tilger, At your request, we have conducted an environmental noise assessment regarding sound levels associated with the Bodin and TXI concrete batch plants located within the industrial district near Boyd Boulevard in the City of Rowlett, TX. This industrial district is located just north of a residential district which includes the neighborhood Dexham Estates. On-site sound level measurements were conducted over a 14-day period to evaluate whether the current noise environment in the industrial district exceeds the City of Rowlett noise ordinance at the property line of the nearby residential district. The results of this noise assessment are documented in this report. Also included herein are detailed graph illustrations and tables of the measured sound level data for your use. Applicable Noise Standards The following noise standards are provided below for your information. Article V: Noise: Section 22-204 – Limitations on Environmental Sound Levels of the City of Rowlett Code of Ordinance states: a.) It shall be a violation of this article for any person to operate or permit to be operated any stationary sources of sound that create a tenth percentile level (L10) or a 90th percentile sound level (L90) that exceeds the limits set forth in the following table for the receiving land use districts when measured five feet above the property boundary. Limiting Sound Levels in dBA District L10 L90 Residential 7:00am – 10:00pm 65 55 10:00pm – 7:00am 60 50 Sunday 7:00am – 9:00am 60 50 Industrial 7:00am – 10:00pm 85 75 10:00pm – 7:00am 85 75 On-Site Sound Level Measurements Continuous 24-hour sound level measurements were conducted simultaneously at two locations between 12:00 p.m. Tuesday, February 9, 2010 and 12:00 p.m. Tuesday, February 23, 2010 to document the existing noise conditions. One sound level meter (SLM-I or Industrial) was ATTACHMENT 1
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Applicable Noise Standards Limiting Sound Levels in dBA
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4801 Spring Valley Road, Suite 113 Dallas TX 75244 972.934.3700 voice 972.934.3720 fax
Wrightson, Johnson, Haddon & Williams, Inc. Designers and Planners for Sound, Video, Multi-Media Telecommunications, Broadcast, Theatre & Acoustics Dallas San Antonio
March 17, 2010
Mr. Joe Tilger City of Rowlett P.O. Box 99 Rowlett, TX 75030 VIA Email: [email protected] Original to follow via U.S. Mail pp 64
RE: City of Rowlett – Environmental Noise Assessment Dear Mr. Tilger,
At your request, we have conducted an environmental noise assessment regarding sound levels associated with the Bodin and TXI concrete batch plants located within the industrial district near Boyd Boulevard in the City of Rowlett, TX. This industrial district is located just north of a residential district which includes the neighborhood Dexham Estates.
On-site sound level measurements were conducted over a 14-day period to evaluate whether the current noise environment in the industrial district exceeds the City of Rowlett noise ordinance at the property line of the nearby residential district. The results of this noise assessment are documented in this report. Also included herein are detailed graph illustrations and tables of the measured sound level data for your use.
Applicable Noise Standards The following noise standards are provided below for your information.
Article V: Noise: Section 22-204 – Limitations on Environmental Sound Levels of the City of Rowlett Code of Ordinance states:
a.) It shall be a violation of this article for any person to operate or permit to be operated any stationary sources of sound that create a tenth percentile level (L10) or a 90th percentile sound level (L90) that exceeds the limits set forth in the following table for the receiving land use districts when measured five feet above the property boundary.
On-Site Sound Level Measurements Continuous 24-hour sound level measurements were conducted simultaneously at two locations between 12:00 p.m. Tuesday, February 9, 2010 and 12:00 p.m. Tuesday, February 23, 2010 to document the existing noise conditions. One sound level meter (SLM-I or Industrial) was
ATTACHMENT 1
Page 2 of 3 17 March 2010
City of Rowlett Environmental Noise Assessment Mr. Joe Tilger
Wrightson, Johnson, Haddon & Williams, Inc. Designers and Planners for Sound, Video, Multi-Media, Telecommunication, Broadcast, Theatre & Acoustics
positioned in the tree line just west of the dead-end portion of Boyd Boulevard to document noise levels in the industrial district and the other sound level meter (SLM-R or Residential) was placed in the tree line near the alley connecting Palomino Drive and Stallion Circle near the residential property line of the Dexham Estates; please see measurement locations on the attached aerial photograph.
Larson-Davis 831 Type I Sound Level Meters were used as data-collection devices at each measurement location. The microphones were fixed to tree branches at an approximate height of 5 ft above grade to simulate the average height of the human ear. The sound level meters measured A-weighted sound pressure level data continuously over the 14-day period, logging applicable sound level data averages (L10, L90, and Leq) at 30-minute intervals to document the typical hour-to-hour noise environment at each location.
As stated in the Applicable Noise Standards section above, the City of Rowlett noise ordinance requires the collection of the statistical noise descriptors L10 and L90 to describe the time-varying character of environmental noise. They are the noise levels equaled or exceeded during 10 and 90 percent of a stated time, respectively. Sound levels associated with L10 typically describe transient or short-term events (e.g. alarms, train whistles, etc.), whereas levels associated with L90 describe the steady-state (or most prevalent) noise conditions.
The City of Rowlett has also requested the Equivalent Sound Level (Leq) data. Because community noise fluctuates over time, Leq is often used to describe the time-varying character of community noise. The Leq is the energy-averaged A-weighted sound level during a measured time interval, and is equal to the level of a continuous steady sound containing the same total acoustical energy over a given time period as the actual time-varying sound.
Data Analysis The sound level data recorded at each location were plotted on separate graphs for each 24-hour measurement period included in the 14-day environmental noise study. The graphs show L10, L90, and Leq data along with the applicable sound level limits as stated in the City of Rowlett noise ordinance in order to compare the measured values to the ordinance limits.
At certain instances during the noise assessment measurement period, measured data was documented to be very close to the ordinance limits. If the data on the graphs appear ambiguous, notes were made stating whether or not the noise ordinance limits were exceeded. To further verify the charted information, all data were recorded in tables organized by date. The data in the tables include the Record# (or meter logging number), Time Frame, and Leq, L10, and L90 sound levels for each of the 30-minute intervals during our 14-day study. All charts and tables are attached to this report for your use.
Since the residential area is of particular interest, data from measurement location SLM-R were compared to data from location SLM-I to determine any possible correlations between levels produced in the industrial district and levels received near the residential area. Measurement data were also compared to the area trash collection in order to eliminate any instantaneous data excluded from the City’s noise ordinance. Train schedules were not available during the time of this analysis; therefore, any noise related to the nearby railway and its effects on the measurements conducted in this study cannot be commented on in this analysis.
ATTACHMENT 1
Page 3 of 3 17 March 2010
City of Rowlett Environmental Noise Assessment Mr. Joe Tilger
Wrightson, Johnson, Haddon & Williams, Inc. Designers and Planners for Sound, Video, Multi-Media, Telecommunication, Broadcast, Theatre & Acoustics
ResultsData shows that the sound level limits set forth in the City’s noise ordinance for residential land use have been exceeded a total of seven (7) times at measurement location SLM-R near the Dexham Estates neighborhood by a maximum of 3 dBA during our 14-day noise study. Table 1 below summarizes these occurrences and compares the measured sound levels to the City’s ordinance residential sound level limits. As shown on the table, all occurrences took place in the nighttime hours between 5:30am and 6:30am when the noise ordinance limits are more stringent.
Date Time L10Limit
L10SLM-R
L90Limit
L90SLM-R
10 Feb 10 6:30am 60 dBA 61.6 dBA - - 16 Feb 10 6:30am - - 50 dBA 51.3 dBA 17 Feb 10 6:00am - - 50 dBA 50.8 dBA 17 Feb 10 6:30am - - 50 dBA 51.9 dBA 18 Feb 10 5:30am - - 50 dBA 51.0 dBA 18 Feb 10 6:00am - - 50 dBA 51.8 dBA 18 Feb 10 6:30am - - 50 dBA 52.7 dBA
Table 1 – Summary of Exceeding Noise Ordinance Level Occurrences at Residential Property Line (SLM-R)
ConclusionsAfter comparing the data at the two (2) measurement locations, no consistent pattern was found that would accurately correlate sound levels from the industrial district with the measured levels at the residential property line exceeding the 50 dBA noise ordinance limit as shown above in Table 1. Since the meter at SLM-R was not monitored on-site during these times, we are unable to determine the cause of the increased sound levels. Since each of these occurrences take place during that specific period of time, it is not unlikely that other noise sources that are exempt from the noise ordinance such as animal noise (birds chirping, dogs barking, etc.), vehicular traffic, airplane overflight, lawn maintenance equipment, and public park attendees may have contributed to these increased sound levels. Train schedules were not available during the time of this analysis; therefore, any noise related to the nearby railway and its effects on the measurements conducted in this study cannot be commented on in this analysis.
I trust you will find this information helpful. If you have any questions or concerns, please do not hesitate to contact us.
Sincerely,Wrightson, Johnson, Haddon, & Williams, Inc.
Kyle Matthis Designer
Cc: Jenny Samson WJHW Greg Hughes WJHW
ATTACHMENT 1
�
SLM
-R
SLM
-I
CityofRowlett-EnvironmentalNoiseAssessment
SoundLevelMeterLocations
WJHW,Inc.
March9,2010 ATTACHMENT 1
City of Rowlett Tuesday, February 9, 2010Environmental Noise Study Charts Industrial
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 9, 2010Measured Night Max Day Max
30 040.050.060.070.080.090.0
essure
Level(dB
A)
Industrial L90 February 9, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 9, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L90 February 9, 2010Measured Night Max Day Max
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial Leq February 9, 2010Measured
ATTACHMENT 1
City of Rowlett Wednesday, February 10, 2010Environmental Noise Study Charts Industrial
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 10, 2010Measured Night Max Day Max
30 040.050.060.070.080.090.0
essure
Level(dB
A)
Industrial L90 February 10, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 10, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L90 February 10, 2010Measured Night Max Day Max
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial Leq February 10, 2010Measured
ATTACHMENT 1
City of Rowlett Thursday, February 11, 2010Environmental Noise Study Charts Industrial
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 11, 2010Measured Night Max Day Max
30 040.050.060.070.080.090.0
essure
Level(dB
A)
Industrial L90 February 11, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 11, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L90 February 11, 2010Measured Night Max Day Max
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial Leq February 11, 2010Measured
ATTACHMENT 1
City of Rowlett Friday, February 12, 2010Environmental Noise Study Charts Industrial
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 12, 2010Measured Night Max Day Max
30 040.050.060.070.080.090.0
essure
Level(dB
A)
Industrial L90 February 12, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 12, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L90 February 12, 2010Measured Night Max Day Max
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial Leq February 12, 2010Measured
ATTACHMENT 1
City of Rowlett Saturday, February 13, 2010Environmental Noise Study Charts Industrial
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 13, 2010Measured Night Max Day Max
30 040.050.060.070.080.090.0
essure
Level(dB
A)
Industrial L90 February 13, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 13, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L90 February 13, 2010Measured Night Max Day Max
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial Leq February 13, 2010Measured
ATTACHMENT 1
City of Rowlett Sunday, February 14, 2010Environmental Noise Study Charts Industrial
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 14, 2010Measured Night Max Day Max
30 040.050.060.070.080.090.0
essure
Level(dB
A)
Industrial L90 February 14, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 14, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L90 February 14, 2010Measured Night Max Day Max
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial Leq February 14, 2010Measured
ATTACHMENT 1
City of Rowlett Monday, February 15, 2010Environmental Noise Study Charts Industrial
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 15, 2010Measured Night Max Day Max
30 040.050.060.070.080.090.0
essure
Level(dB
A)
Industrial L90 February 15, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 15, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L90 February 15, 2010Measured Night Max Day Max
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial Leq February 15, 2010Measured
ATTACHMENT 1
City of Rowlett Tuesday, February 16, 2010Environmental Noise Study Charts Industrial
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 16, 2010Measured Night Max Day Max
30 040.050.060.070.080.090.0
essure
Level(dB
A)
Industrial L90 February 16, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 16, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L90 February 16, 2010Measured Night Max Day Max
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial Leq February 16, 2010Measured
ATTACHMENT 1
City of Rowlett Wednesday, February 17, 2010Environmental Noise Study Charts Industrial
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 17, 2010Measured Night Max Day Max
30 040.050.060.070.080.090.0
essure
Level(dB
A)
Industrial L90 February 17, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 17, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L90 February 17, 2010Measured Night Max Day Max
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial Leq February 17, 2010Measured
ATTACHMENT 1
City of Rowlett Thursday, February 18, 2010Environmental Noise Study Charts Industrial
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 18, 2010Measured Night Max Day Max
30 040.050.060.070.080.090.0
essure
Level(dB
A)
Industrial L90 February 18, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 18, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L90 February 18, 2010Measured Night Max Day Max
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial Leq February 18, 2010Measured
ATTACHMENT 1
City of Rowlett Friday, February 19, 2010Environmental Noise Study Charts Industrial
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 19, 2010Measured Night Max Day Max
30 040.050.060.070.080.090.0
essure
Level(dB
A)
Industrial L90 February 19, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 19, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L90 February 19, 2010Measured Night Max Day Max
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial Leq February 19, 2010Measured
ATTACHMENT 1
City of Rowlett Saturday, February 20, 2010Environmental Noise Study Charts Industrial
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 20, 2010Measured Night Max Day Max
30 040.050.060.070.080.090.0
essure
Level(dB
A)
Industrial L90 February 20, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 20, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L90 February 20, 2010Measured Night Max Day Max
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial Leq February 20, 2010Measured
ATTACHMENT 1
City of Rowlett Sunday, February 21, 2010Environmental Noise Study Charts Industrial
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 21, 2010Measured Night Max Day Max
30 040.050.060.070.080.090.0
essure
Level(dB
A)
Industrial L90 February 21, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 21, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L90 February 21, 2010Measured Night Max Day Max
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial Leq February 21, 2010Measured
ATTACHMENT 1
City of Rowlett Monday, February 22, 2010Environmental Noise Study Charts Industrial
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 22, 2010Measured Night Max Day Max
30 040.050.060.070.080.090.0
essure
Level(dB
A)
Industrial L90 February 22, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 22, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L90 February 22, 2010Measured Night Max Day Max
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial Leq February 22, 2010Measured
ATTACHMENT 1
City of Rowlett Tuesday, February 23, 2010Environmental Noise Study Charts Industrial
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 23, 2010Measured Night Max Day Max
30 040.050.060.070.080.090.0
essure
Level(dB
A)
Industrial L90 February 23, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L10 February 23, 2010Measured Night Max Day Max
0.010.020.030.040.050.060.070.080.090.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial L90 February 23, 2010Measured Night Max Day Max
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
Soun
dPressure
Level(dB
A)
Time of Day (HH:MM)
Industrial Leq February 23, 2010Measured
ATTACHMENT 1
City of Rowlett Tuesday, February 9, 2010Environmental Noise Study Raw Data Industrial