NOISE IMPACT ANALYSIS

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NOISE IMPACT ANALYSIS

Montiel Road Tentative Map No. 14-006 2110 Montiel Road

San Marcos, California 92069

Prepared For

Montiel Rd Partners, LP Attention: Robert Flynn 2445 Brant Street, Suite 511 San Diego, California 92101

Phone: 858-356-4120

Prepared By

Eilar Associates, Inc.

Acoustical & Environmental Consulting 210 South Juniper Street, Suite 100

Escondido, California 92025 www.eilarassociates.com

Phone: 760-738-5570 Fax: 760-738-5227

Job #B70206N1

Original Report: March 9, 2017 Revised: June 27, 2017

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TABLE OF CONTENTS

Page

1.0 EXECUTIVE SUMMARY 1

2.0 INTRODUCTION 1

2.1 Project Description 2.2 Project Location

2.3 Applicable Noise Standards

3.0 ENVIRONMENTAL SETTING 3

3.1 Existing Noise Environment 3.2 Future Noise Environment

4.0 METHODOLOGY AND EQUIPMENT 7

4.1 Methodology

4.2 Measurement Equipment

5.0 IMPACTS AND MITIGATION 10

5.1 Traffic Noise Impacts

5.2 Project-Related Noise Impacts on Surrounding Property Lines

6.0 CONCLUSION 15

7.0 CERTIFICATION 16

8.0 REFERENCES 17

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FIGURES

1. Vicinity Map

2. Assessor’s Parcel Map 3. Satellite Aerial Photograph 4. Topographic Map

5. Site Plan Showing Current Traffic CNEL Contours and Noise Measurement Location 6. Site Plan Showing Future Traffic CNEL Contours and Noise Measurement Location 7. Site Plan Showing Future Traffic CNEL Impacts at Outdoor Use Areas with Barrier Walls 8. Site Plan Showing Future Traffic CNEL Impacts at Building Facades

9. Satellite Aerial Photograph Showing Mechanical Equipment Noise Contours and Receiver Locations

10. Satellite Aerial Photograph Showing Construction Noise Source and Receiver Locations

APPENDICES A. Project Plans

B. Pertinent Sections of the City of San Marcos Noise Element to the General Plan and Municipal Code

C. Traffic Noise Model (TNM) Data and Results D. Manufacturer Data Sheets

E. Exterior-to-Interior Noise Analysis F. Cadna Analysis Data and Results

G. Construction Equipment Noise Calculations

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Eilar Associates, Inc. Job #B70206N1 June 27, 2017 Page 1

1.0 EXECUTIVE SUMMARY

The proposed project, known as Montiel Road Tentative Map No. 14-006, consists of the subdivision of the site to contain nine single-family residential lots. The project site is located at 2110 Montiel Road in the City of San Marcos, California. This report has been prepared to assess noise impacts in comparison to the applicable standards of the City of San Marcos Noise Element to the General Plan and the City of San Marcos Municipal Code.

The City of San Marcos Noise Element to the General Plan states that exterior noise levels of single- family residential land uses should not exceed 60 CNEL in order to be considered “acceptable.” A noise analysis was performed to determine anticipated future noise impacts at facades and proposed private outdoor use areas (backyards) of lots on the project site. Calculations show that, without mitigation, future noise levels are expected to exceed 60 CNEL at proposed outdoor use areas. In order to attenuate noise levels to below 60 CNEL at proposed outdoor use areas, six-foot high sound barrier walls have been proposed around outdoor use areas. Please refer to Section 5.1 for additional information.

The City of San Marcos and the State of California require interior noise levels of 45 CNEL or less in residences. Calculations show that future noise levels on site exceed 60 CNEL at most of the lots on site. A preliminary analysis of interior noise levels demonstrates that residences on site are expected to comply with interior noise requirements with standard construction in place and the implementation of mechanical ventilation systems.

Calculations show that noise levels generated by anticipated HVAC units are expected to meet the applicable noise limits at surrounding property lines, as currently designed. No added project design features are deemed necessary for attenuating these mechanical noise impacts.

Noise from temporary construction activities is not expected to exceed typical daytime noise limits at any surrounding property line. Nighttime construction is prohibited, and specific hours for operation are detailed in the City of San Marcos Municipal Code. Standard construction noise control methods including adhering to permissible hours of operation, maintaining equipment in proper operating condition, and placing staging areas at furthest locations from noise sensitive receivers are expected to be sufficient for reducing noise impacts to surrounding receivers.

2.0 INTRODUCTION

This acoustical analysis report is submitted to satisfy the noise requirements of the City of San Marcos. Its purpose is to assess noise impacts from nearby roadway traffic and to identify project features or requirements necessary to achieve exterior noise levels of 60 CNEL or less at outdoor useable areas. Feasibility of interior noise mitigation will also be addressed. Additionally, this report assesses noise impacts from potential on-site project-related noise sources, such as mechanical equipment and temporary construction, to determine if mitigation is necessary to reduce the noise impacts to levels that are less than significant or in compliance with applicable standards.

All noise level or sound level values presented herein are expressed in terms of decibels (dB), with A-weighting, abbreviated "dBA," to approximate the hearing sensitivity of humans. Time-averaged noise levels are expressed by the symbol “LEQ.” Unless a different time period is specified, “LEQ” is implied to mean a period of one hour. Some of the data may also be presented as octave-band-

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filtered and/or A-octave-band-filtered data, which are a series of sound spectra centered about each stated frequency, with half of the bandwidth above and half of the bandwidth below each stated frequency. This data is typically used for machinery noise analysis and barrier calculations.

The Community Noise Equivalent Level (CNEL) is a calculated 24-hour weighted average, where sound levels during evening hours of 7 p.m. to 10 p.m. have an added 5 dB weighting, and sound levels during nighttime hours of 10 p.m. to 7 a.m. have an added 10 dB weighting. This is similar to the Day-Night Sound Level (LDN), which is a 24-hour average with 10 dB added weighting on the same nighttime hours but no added weighting on the evening hours. Sound levels expressed in CNEL are always based on A-weighted decibels. These data unit metrics are used to express noise levels for both measurement and municipal noise ordinances and regulations, for land use guidelines, and enforcement of noise ordinances. Further explanation can be provided upon request.

Sound pressure is the actual noise experienced by a human or registered by a sound level instrument.

When sound pressure is used to describe a noise source, the distance from the noise source must be specified in order to provide complete information. Sound power, on the other hand, is a specialized analytical method to provide information without the distance requirement, but it may be used to calculate the sound pressure at any desired distance.

2.1 Project Description

The proposed project, known as the Montiel Road Tentative Map No, 14-006, consists of the subdivision of the site to contain nine single-family residential lots on approximately 2.7 acres. Lot 1 of the proposed site is currently occupied by an existing residence. The existing residence on Lot 1 of the tentative map will remain as-is. Lots 2 through 9 of the proposed site are currently vacant.

The average net lot size will be 10,010 square feet. The project site and surrounding properties to the north, east, and west are zoned Residential Low (R-1-10), while the parcel to the southwest is zoned Commercial (C) and the parcel to the southeast is zoned Specific Plan Area (SPA).

For additional project details, please refer to the project plans provided in Appendix A.

2.2 Project Location

The project site is located at 2110 Montiel Road in the City of San Marcos, California. The Assessor’s Parcel Numbers (APN) for the site are 228-120-09, 228-120-33, and 228-120-34. Lot 1 of the proposed site is currently occupied by a residence. Lots 2 through 9 of the proposed site are currently vacant.

For a graphical representation of the site, please refer to the Vicinity Map, Assessor’s Parcel Map, Satellite Aerial Photograph, and Topographic Map, provided as Figures 1 through 4, respectively.

2.3 Applicable Noise Standards

This acoustical analysis report is submitted to satisfy the acoustical requirements of the City of San Marcos Noise Element to the General Plan. The Noise Element states that exterior noise levels at outdoor use areas of residential property should not exceed 60 CNEL. In the event that noise levels exceed 60 CNEL, mitigation must be proposed to bring noise levels into compliance. For lots with net areas ranging from 4,000 square feet to 10 acres, as is the case for the lots on this parcel, at least 10% of the net lot area must be noise-protected. In addition, the interior noise levels of the on-site residences must not exceed 45 CNEL, as per the Noise Element as well as the State of California

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Building Code. Pertinent sections of the City of San Marcos Noise Element to the General Plan are provided as Appendix B.

According to the City of San Marcos Municipal Code, Title 20 – Zoning Ordinance, Table 20.300-4, average noise levels shall not exceed 60 dBA LEQ between the hours of 7 a.m. and 10 p.m. and 50 dBA LEQ between the hours of 10 p.m. and 7 a.m. at single-family residential properties. At commercial properties, average noise levels shall not exceed 60 dBA LEQ between the hours of 7 a.m. and 10 p.m. and 55 dBA LEQ between the hours of 10 p.m. and 7 a.m.

Additionally, temporary project-generated construction noise must be controlled at surrounding property lines. The City of San Marcos does not have a specific construction noise limit, so the County of San Diego construction noise limit of 75 dBA will be used. Permanent project-generated noise limits will be based on the City of San Marcos Noise Element which states that an hourly noise level of 60 dBA is considered “acceptable” for impacts to residential property.

3.0 ENVIRONMENTAL SETTING

3.1 Existing Noise Environment

The primary noise sources in the vicinity of the project site are automobile and truck traffic noise from Montiel Road and State Route 78 (SR-78). No other noise sources are considered significant.

3.1.1 Roadway Traffic Sources

Current (2012) and future (2035) traffic volumes are given based on information from the San Diego Association of Governments (SanDAG) Series 13 Transportation Forecast Information Center, located on the SanDAG website at http://tfic.sandag.org/, and the SANTEC / ITE Guidelines for Traffic Impact Studies (see reference).

Montiel Road is a two-lane, two-way Collector running east-west along the south boundary of the project site. The posted speed limit is 40 mph. Montiel Road currently carries a traffic volume of approximately 8,200 Average Daily Trips (ADT) west of Via Flora Road and approximately 6,700 ADT east of Via Flora Road, according to SanDAG traffic volumes.

State Route 78 (SR-78) is a six-lane, two-way Freeway running east-west to the south of the project site. The posted speed limit is 65 mph. According to SanDAG traffic volumes, west of Exit 15 (Nordahl Road), SR-78 currently carries a traffic volume of approximately 77,400 ADT westbound and approximately 74,500 ADT eastbound. East of Exit 15, SR-78 currently carries a traffic volume of approximately 86,600 ADT westbound and approximately 82,400 ADT eastbound, according to SanDAG traffic volumes.

SR-78 has two exit ramps at Exit 15 (Nordahl Road). Each exit ramp is a one-lane, one-way Local Ramp connecting SR-78 and Nordahl Road. The posted speed limit is 30 mph. The SR-78 ramps currently carry a traffic volume of approximately 9,300 ADT westbound and approximately 8,000 ADT eastbound, according to SanDAG traffic volumes.

No current or future truck percentages were available for any of the roadways in the vicinity of the project site with the exception of SR-78; however, based on neighboring and surrounding land use, roadway classification, professional experience with similar projects, and on-site observations, a truck

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percentage mix of 2.0% medium trucks and 1.0% heavy trucks was used for Montiel Road. Vehicle mix information for SR-78 was obtained from the Caltrans Traffic Census, and was determined to be approximately 2.1% medium trucks and 2.4% heavy trucks in the vicinity of the project site.

Current and future (See Section 3.2) traffic volumes and vehicle mixes for roadway sections near the project site are shown in Table 1. For more information, please refer to Appendix C: Traffic Noise Model (TNM) Data and Results.

Table 1. Overall Roadway Traffic Information

Roadway Name Direction

Speed Limit (mph)

Vehicle Mix (%)

Current ADT (2012)

Future ADT (2035) Medium

Trucks

Heavy Trucks Montiel Road

West of Via Flora Road -- 40 2.0 1.0 8,200 10,000

Montiel Road

East of Via Flora Road -- 40 2.0 1.0 6,700 10,000

SR-78 West of Exit 15

Westbound 65 2.1 2.4 77,400 88,900

Eastbound 65 2.1 2.4 74,500 85,800

SR-78 East of Exit 15

Westbound 65 2.1 2.4 86,600 98,300

Eastbound 65 2.1 2.4 82,400 95,000

SR 78 Exit Ramp

Westbound 30 2.1 2.4 9,300 9,400

Eastbound 30 2.1 2.4 8,000 9,100

Current traffic noise contours were calculated for the project site using Traffic Noise Model, without considering shielding from existing or proposed project structures. The site is exposed to current traffic noise levels ranging from approximately 63 CNEL at the north boundary of the project site to 70 CNEL at the south boundary of the site. For a graphical representation of traffic noise contours, please refer to Figure 5: Site Plan Showing Current Traffic CNEL Contours and Noise Measurement Location.

3.1.2 Measured Noise Level

An on-site inspection and traffic noise measurement were made on the morning of Tuesday, February 28, 2017. The weather conditions were as follows: cloudy skies, winds at 6 to 8 mph, moderate humidity, and temperatures in the mid-50s. A noise measurement was taken south of the project site, approximately 23 feet south of the Montiel Road centerline. The microphone position was approximately five feet above the existing grade. The dominant source of noise during the measurement was traffic noise from Montiel Road and State Route 78, with some noise contribution from activity in the surrounding neighborhood. The measured noise level is presented in Table 2, and the measurement location is shown graphically in Figures 5 and 6.

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Table 2. On-Site Noise Measurement Conditions and Results

Date Tuesday, February 28, 2017

Time 10:20 a.m. – 10:38 a.m.

Conditions Cloudy skies, winds at 6-8 mph,

temperature in the mid-50s with moderate humidity

Measured Noise Level 67.1 dBA LEQ

3.1.3 Calculated Noise Level

Noise levels were calculated for the site using the methodology described in Section 4.1.2 for the location, conditions, and traffic volumes counted during the noise measurements. The calculated noise levels (LEQ) were compared with the measured on-site noise level to determine if adjustments or corrections (calibration) should be applied to the traffic noise prediction model. Adjustments are intended to account for site-specific differences, such as reflection and absorption, which may be greater or lesser than accounted for in the model.

The measured noise level of 67.1 dBA LEQ to the south of the property was compared to the calculated (modeled) noise level of 66.7 dBA LEQ, for the same conditions and traffic flow. According to the Federal Highway Administration’s Highway Traffic Noise: Analysis and Abatement Guide (see reference), a traffic noise model is considered validated if the measured and calculated noise impacts differ by three decibels or less. No adjustment was deemed necessary to model future noise levels for this location as the difference between the measured and calculated levels was found to be less than three decibels. The Traffic Noise Model is assumed to be representative of actual traffic noise that is experienced on site. This information is presented in Table 3.

3.2 Future Noise Environment 3.2.1 Future Traffic Volumes

The future on-site noise environment will be the result of the same traffic noise sources, as well as the noise generated by the proposed uses at the project site. Future traffic volumes for SR-78 were provided by SanDAG for the year 2035. The future traffic volumes for Montiel Road were determined using the Level of Service (LOS) C for that roadway, according to the SANTEC / ITE Guidelines for Traffic Impact Studies (see reference).

In the vicinity of the project site, the traffic volume of Montiel Road is expected to increase to approximately 10,000 Average Daily Trips (ADT). The traffic volume of SR-78 west of Exit 15 (Nordahl Road) is expected to increase to approximately 88,900 ADT westbound and approximately 85,800 ADT eastbound. East of Exit 15, the traffic volume on SR-78 is expected to increase to approximately 98,300 ADT westbound and approximately 95,000 ADT eastbound. The traffic volume

Table 3. Calculated versus Measured Traffic Noise Data

Location Calculated Measured Difference Correction 23 feet south of Montiel Road centerline 66.7 dBA LEQ 67.1 dBA LEQ 0.4 dB None Applied

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of the SR-78 exit ramps is expected to increase to approximately 9,400 ADT westbound and approximately 9,100 ADT eastbound.

The same truck percentages from the current environment were used for future traffic volume modeling. SR-78 is anticipated to add two additional High Occupancy Vehicle (HOV) lanes, one traveling in each direction, and therefore, the future traffic noise model was adjusted accordingly. For further roadway details and projected future ADT traffic volumes, please refer to Appendix C: Traffic Noise Model (TNM) Data and Results.

Future traffic noise contours were calculated for the project site using Traffic Noise Model, without considering shielding from existing or proposed project structures. The site will be exposed to traffic noise levels ranging from approximately 63 CNEL at the north boundary of the project site to 70 CNEL at the south boundary of the site. For a graphical representation of traffic noise contours, please refer to Figure 6: Site Plan Showing Future Traffic CNEL Contours and Noise Measurement Location.

3.2.2 Air Conditioning Units

The primary noise generators on the project site will be air conditioning units at each residence. The manufacturer/model of air conditioning units on site is currently unknown, and for this reason, typical assumptions have been made for purposes of this noise analysis. It is assumed that each residence would require an air conditioning unit with a capacity of approximately seven tons, and that units would be ground-mounted near the rear of the pads designated on project plans. Two units were placed at each pad, one three-ton unit and one four-ton unit. Typical air conditioning units manufactured by Carrier (model 24ACC6) have been used in this analysis, and are assumed to be representative of equipment that could be used on site in the future. . The overall sound power level and octave band power levels of the units were provided by Carrier. As the sum of the octave band levels does not equal the total sound power level, the octave band levels have been adjusted to equal the overall sound power level. The sound power levels of the units are shown below in Table 4.

Manufacturer data sheets are provided in Appendix D: Manufacturer Data Sheets.

Table 4. Sound Power Levels of Carrier Model 24ACC6 Unit Size

Sound Power at Octave Band Frequency (dB) Total Sound Power

(dBA)

125 250 500 1K 2K 4K 8K

3-ton 54.0 63.0 66.0 68.0 63.0 60.5 53.5 72

4-ton 60.5 63.5 67.5 68.5 64.5 60.5 53.5 73

3.2.3 Temporary Construction Equipment

Construction information was not available at the time this study was prepared. Typical construction equipment has been selected for analysis based on the work expected to be performed. Unless otherwise noted, construction equipment noise levels were obtained from the Department for Environment Food and Rural Affairs (DEFRA) Update of Noise Database for Prediction of Noise on Construction and Open Sites. Noise levels are shown in Table 5.

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Table 5. Typical Construction Equipment Noise Levels

Equipment Description Duty Cycle (%) Noise Level at 50 feet (dBA)

Dozer 40 77

Grader¹ 40 70

Water Truck¹ 40 77

Excavator 40 75

Concrete Mixer Truck 40 76

Concrete Pump 20 74

Paver 40 73

Roller 40 73

1Source: Noise measurements performed by Eilar Associates on March 25, 2010 for Brutoco Engineering &

Construction, Inc. for the Orange Line Extension Project, Metro Contract #C0943, City of Los Angeles, California.

4.0 METHODOLOGY AND EQUIPMENT

4.1 Methodology 4.1.1 Field Measurement

Typically, a “one-hour” equivalent sound level measurement (LEQ, A-Weighted) is recorded for at least one noise-sensitive location on the site. During the on-site noise measurement, start and end times are recorded, vehicle counts are made for cars, medium trucks (double-tires/two axles), and heavy trucks (three or more axles) for the corresponding road segment(s). Supplemental sound measurements of one hour or less in duration are often made to further describe the noise environment of the site.

For measurements of less than one hour in duration, the measurement time is long enough for a representative traffic volume to occur and the noise level (LEQ) to stabilize. The vehicle counts are then converted to one-hour equivalent volumes by applying an appropriate factor. Other field data gathered include measuring or estimating distances, angles-of-view, slopes, elevations, roadway grades, and vehicle speeds. This information is subsequently verified using available maps and records.

4.1.2 Roadway Noise Calculation

The Traffic Noise Model software, TNM Version 2.5 released in February 2004 by the U. S.

Department of Transportation was used for all traffic modeling in the preparation of this report. TNM calculates the daytime average Hourly Noise Level (HNL) from traffic data including road alignment, elevation, lane configuration, projected traffic volumes, estimated truck composition percentages and vehicle speeds. The HNL is equivalent to the LEQ, and may be converted to CNEL by the addition of 2.0 decibels, as suggested in the Wyle Laboratories Study (see reference). The daytime average hourly traffic volume, evaluated from Average Daily Trips (ADT) data as shown in the Wyle Study to

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be simply 5.8% of ADT, is then applied to models in TNM. Current and future CNEL is calculated for predetermined receiver locations. Noise attenuation methods may be analyzed, tested, and planned with TNM, as required. Further explanation can be supplied on request.

4.1.3 Exterior-to-Interior Analysis

The State of California and the City of San Marcos require buildings to be designed in order to attenuate, control, and maintain average interior noise levels not greater than 45 CNEL in residential space. Contemporary exterior building construction is expected to achieve at least 15 decibels of exterior-to-interior noise attenuation with windows opened, according to the U.S. Environmental Protection Agency Office of Noise Abatement and Control (see reference). As a result, exterior noise levels of more than 60 CNEL often result in interior conditions that fail to meet the 45 CNEL requirements for habitable space.

Analysis for the interior noise levels requires consideration of:

• Number of unique assemblies in the wall (doors, window/wall mount air conditioners, sliding glass doors, and windows)

• Size, number of units, and sound transmission data for each assembly type

• Length of sound impacted wall(s)

• Depth of sound impacted room

• Height of exterior wall of sound impacted room

• Exterior noise level at wall assembly or assemblies of sound impacted room

The Composite Sound Transmission data is developed for the exterior wall(s) and the calculated noise exposure is converted to octave band sound pressure levels (SPL) for a typical traffic type noise. The reduction in room noise due to absorption is calculated and subtracted from the interior octave noise levels, and the octave band noise levels are logarithmically summed to yield the overall interior room noise level. When interior noise levels exceed 45 CNEL in residential space, the noise reduction achieved by each element is reviewed to determine which changes will achieve the most cost-effective compliance. Windows are usually the first to be reviewed, followed by exterior doors, and then exterior walls.

4.1.4 Cadna Noise Modeling

Modeling of the outdoor noise environment is accomplished using Cadna Version 2017, which is an industry-standard, model-based computer program developed by DataKustik for predicting noise impacts in a wide variety of conditions. Cadna (Computer Aided Noise Abatement) assists in the calculation, presentation, assessment, and alleviation of noise exposure. It allows for the input of project information such as noise source data, barriers, structures, and topography to create a detailed model and uses the most up-to-date calculation standards to predict outdoor noise impacts.

Noise standards used by Cadna that are particularly relevant to this analysis include ISO 9613 (Attenuation of sound during propagation outdoors). Cadna provides results that are in line with basic acoustical calculations for distance attenuation and barrier insertion loss. Further explanation may be provided upon request.

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4.1.5 Formulas and Calculations

Decibel Addition

To determine the combined logarithmic noise level of two known noise source levels, the values are converted to the base values, added together, and then converted back to the final logarithmic value, using the following formula:

) 10 10

10 log(

10

^L¹^/¹⁰ ^L²^/¹⁰ ^LN^/¹⁰

L

C

= + + Κ

where LC = the combined noise level (dB), and LN = the individual noise sources (dB).

This procedure is also valid when used successively for each added noise source beyond the first two. The reverse procedure can be used to estimate the contribution of one source when the contribution of another concurrent source is known and the combined noise level is known. These methods can be used for LEQ or other metrics (such as LDN or CNEL), as long as the same metric is used for all components.

Attenuation Due To Distance

Attenuation due to distance is calculated by the equation:

) log(

20

1 2 1

2 D

SPL D SPL = −

where SPL1 = Known sound pressure level at known distance, SPL2 = Calculated sound pressure level at distance,

D1 = Distance from source to location of known sound pressure level, and D2 = Distance from source to location of calculated sound pressure level.

This is identical to the more commonly used reference of 6 dB reduction for every doubling of distance. This equation does not take into account reduction in noise due to atmospheric absorption.

4.2 Measurement Equipment

Some or all of the following equipment was used at the site to measure existing ambient noise levels:

• Larson Davis Sound Expert LxT Type 1 Sound Level Meter, Serial #4084

• Larson Davis Model CA250 Calibrator, Serial #2106

• Tripod, microphone & windscreen

The sound level meter was field-calibrated immediately prior to the noise measurement and checked afterwards, to ensure accuracy. All sound level measurements conducted and presented in this report, in accordance with the regulations, were made with sound level meters that conform to the American National Standards Institute specifications for sound level meters (ANSI S1.4). All instruments are maintained with National Bureau of Standards traceable calibration, per the manufacturers’ standards.

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5.0 IMPACTS AND MITIGATION

5.1 Traffic Noise Impacts

5.1.1 Exterior Traffic Noise Impacts

The City of San Marcos Noise Element to the General Plan states that noise exposure to outdoor use areas of single-family residences should not exceed 60 CNEL in order to be considered acceptable.

Noise contours indicate that the entire site will be exposed to noise levels exceeding 60 CNEL in the future noise environment.

Receivers have been placed in the Traffic Noise Model at the anticipated outdoor use areas. These calculated noise levels consider shielding that would be provided by proposed project buildings. As shown in Table 6, the exterior traffic noise level exceeds 60 CNEL at all proposed outdoor use areas, therefore mitigation will be necessary. Noise attenuation barriers (6 feet high) have been modeled to demonstrate that achieving 60 CNEL is feasible. At the time of building permit application, alternate mitigation measures may be proposed for any lot, including the use of architectural features (the residential structure) as mitigation or the combination of the residential structure and a free-standing sound wall, provided the lot can still provide the required noise-protected area. Approximate sound barrier locations and outdoor use receiver locations are shown in Figure 7. Mitigated noise levels are shown in Table 6.

Table 6. Future Traffic Noise Levels at Outdoor Use Areas

Receiver Location

Exterior Traffic Noise Level (CNEL)

Without Barrier Mitigation With Barrier Mitigation

OU1 Lot 1, West 65.2 58.9

OU2 Lot 2, West 63.7 56.5

OU3 Lot 3, West 63.2 54.5

OU4 Lot 4, West 62.6 53.6

OU5 Lot 5, West 61.8 53.5

OU6 Lot 6, East 61.2 53.0

OU7 Lot 7, East 62.4 54.1

OU8 Lot 8, East 62.8 55.2

OU9 Lot 9, East 63.6 56.3

A sound attenuation wall should be solid and constructed of masonry, wood, plastic, fiberglass, steel, or a combination of those materials, with no cracks or gaps, through or below the wall. Any seams or cracks must be filled or caulked as much as possible. If wood is used, it can be tongue and groove and must be at least 7/8-inch thick or have a surface density of at least 3-1/2 pounds per square foot.

Where architectural or aesthetic factors allow, glass or clear plastic may be used on the upper portion, if it is desirable to preserve a view. A glass or plexiglass railing wall at specified patios and balconies should be sufficient in these locations.

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Eilar Associates, Inc. Job #B70206N1 June 27, 2017 Page 11 Receivers have been placed in the Traffic Noise Model at the anticipated building facades on the first and second floors for each lot on site to determine specific noise impacts at each location. Please refer to Table 7 for future traffic noise levels at the proposed building facades. These calculated noise levels consider shielding that would be provided by anticipated project buildings. For a graphical representation of the building facade receiver locations, please refer to Figure 8.

Table 7. Future Traffic Noise Levels at Building Facades

Receiver Location Exterior Traffic Noise Level (CNEL) First Floor Second Floor

F1 Lot 1, North 55.5 --

F2 Lot 1, East 62.8 --

F3 Lot 1, South 67.4 --

F4 Lot 1, West 64.0 --

F5 Lot 2, North 52.1 54.1

F6 Lot 2, East 57.8 63.8

F7 Lot 2, South 61.5 67.2

F8 Lot 2, West 63.3 64.8

F9 Lot 3, North 51.8 53.6

F10 Lot 3, East 62.4 63.7

F11 Lot 3, South 62.2 63.7

F12 Lot 3, West 63.0 63.8

F13 Lot 4, North 51.4 52.9

F14 Lot 4, East 61.7 62.8

F15 Lot 4, South 62.3 63.3

F16 Lot 4, West 61.1 62.6

F17 Lot 5, North 47.5 52.1

F18 Lot 5, East 59.2 60.4

F19 Lot 5, South 61.4 62.3

F20 Lot 5, West 61.8 62.3

F21 Lot 6, North 50.8 52.3

F22 Lot 6, East 61.1 62.1

F23 Lot 6, South 56.4 58.7

F24 Lot 6, West 57.3 59.1

F25 Lot 7, North 51.0 52.4

F26 Lot 7, East 61.8 62.7

F27 Lot 7, South 59.5 61.1

F28 Lot 7, West 57.8 59.9

F29 Lot 8, North 48.6 52.8

F30 Lot 8, East 62.1 63.2

F31 Lot 8, South 60.1 63.3

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Eilar Associates, Inc. Job #B70206N1 June 27, 2017 Page 12 Table 7. Future Traffic Noise Levels at Building Facades

Receiver Location Exterior Traffic Noise Level (CNEL) First Floor Second Floor

F32 Lot 8, West 59.8 61.9

F33 Lot 9, North 52.3 53.8

F34 Lot 9, East 61.5 63.1

F35 Lot 9, South 65.4 66.7

F36 Lot 9, West 62.0 63.0

As shown above, future noise levels at the building facades will exceed 60 CNEL at most locations.

Appropriate mitigation will be necessary to attenuate interior traffic noise levels on the proposed project site.

5.1.2 Interior Noise Impacts

The State of California requires buildings to be designed in order to attenuate, control, and maintain interior noise levels to 45 CNEL or less in habitable residential space. Current exterior building construction is generally expected to achieve at least 15 decibels of exterior-to-interior noise attenuation, with windows opened, according to the U.S. EPA. Therefore, proposed project building structures exposed to exterior noise levels greater than 60 CNEL could be subject to interior noise levels exceeding the 45 CNEL noise limit for residential habitable space.

Calculations show that future noise levels on site exceed 60 CNEL at the first and second floors of residences on all lots of the proposed development. A preliminary interior noise analysis was performed for a typical kitchen and bedroom to determine the feasibility of achieving compliant interior noise levels. Results of the typical interior noise analysis are shown in Table 8. Detailed calculations can be found in Appendix E: Exterior-to-Interior Noise Analysis.

Table 8. Anticipated Future Noise Levels in Typical Interior Spaces

Room

Maximum Exterior Facade Impact

(CNEL)

Modeled Window STC Rating

Interior Noise Level (CNEL) Windows Open Windows Closed

Kitchen 67.1 20 58.5 41.6

Bedroom 67.1 20 57.3 40.2

Sample calculations show that compliant interior noise levels are feasible and can be achieved with standard construction methods. Exterior windows and glass doors would need to remain closed to achieve compliant interior noise levels, and therefore appropriate means of air circulation and provision of fresh air would need to be present to allow windows to remain closed for extended intervals of time so that acceptable levels of noise can be maintained on the interior. Therefore, a mechanical ventilation system would need to be required for all residential units on site. With standard construction and mechanical ventilation in place, interior noise levels are anticipated to comply with the applicable standards of the City of San Marcos and the State of California.

5.2 Project-Related Noise Impacts on Surrounding Property Lines 5.2.1 HVAC Noise

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_______________________________________________________________________________

Eilar Associates, Inc. Job #B70206N1 June 27, 2017 Page 13 Anticipated HVAC noise levels have been calculated using Cadna at surrounding noise-sensitive receivers, considering noise limits detailed in Section 2.3. Calculations take into account the proposed residential buildings on site. HVAC units have been modeled at a height of 3.28 feet (1 meter) above pad elevations. Receivers have been placed at five feet above grade at all surrounding property lines. Calculations assume that all HVAC units will be operational for 100 percent of the time during all hours of the day, for a worst-case analysis, although actual operation would be expected to be intermittent and less frequent during the more sensitive nighttime hours.

Results of the analysis are shown in Table 9. More information is provided in Appendix F: Cadna Analysis Data and Results, and a graphical representation of noise contours and evaluated equipment/receiver locations is shown in Figure 9.

Table 9. Mechanical Equipment Noise Levels at Surrounding Receivers

Receiver Location Nighttime Noise Limit (dBA) Equipment Noise Level (dBA)

R1 West 50 43.7

R2 West 50 44.9

R3 West 50 43.9

R4 West 50 43.7

R5 West 50 47.5

R6 North 50 15.5

R7 East 50 46.6

R8 East 50 45.1

R9 East 50 41.1

R10 East 50 39.7

R11 South 50 35.1

R12 South 55 33.4

As shown above, noise levels from proposed HVAC equipment on site are expected to meet the applicable noise limits set by the City of San Marcos without the implementation of added project design features. This evaluation is considered to be representative of actual HVAC noise generated on site, although noise levels may be further reduced due to units cycling on and off periodically.

5.2.2 Temporary Construction Noise

The anticipated construction activity was evaluated to determine potential temporary noise impacts to the surrounding noise sensitive residential receivers to the west and to the south of the project site.

Any other potentially noise-sensitive receivers are located at a greater distance from construction activity and therefore, would be exposed to lesser noise impacts due to distance attenuation and shielding provided by intervening structures. The City of San Marcos does not have a specific construction noise limit, so the County of San Diego construction noise limit of 75 dBA will be used.

Typical noise levels of construction equipment that may be used on site are listed in Section 3.2.3, Table 5.

Noise levels were calculated at the nearest receiver to the west and the nearest receiver to the south.

The noise sources were placed near the center of the parcel, to evaluate worst-case impacts to the surrounding receivers as equipment moves around the property. Noise calculations consider typical duty cycles of equipment, to account for periods of activity and inactivity on the site.

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_______________________________________________________________________________

Eilar Associates, Inc. Job #B70206N1 June 27, 2017 Page 14 Noise levels for each stage of construction are shown in Table 10. Detailed calculations can be found in Appendix G: Construction Equipment Noise Calculations, and a graphical representation of noise source and receiver locations is provided as Figure 10.

Table 10. Temporary Construction Noise Levels at Nearest Occupied Property

Stage Equipment Used Receiver Approximate Distance (ft)

Average Noise Level of Equipment (dBA) Grading Dozer, Grader, Water

Truck, Excavator

C1 - South 88 72.6

C2 - West 154 68.7

Foundation Concrete Mixer Truck, Concrete Pump

C1 - South 88 68.3

C2 - West 154 63.4

Paving Paver, Roller C1 - South 88 67.1

C2 - West 154 59.2

Calculations show that construction noise levels associated with this project will not create a significant impact at any surrounding property line. During acceptable hours of operation and with typical anticipated activity taking place, noise levels are expected to remain below 75 dBA.

Although noise levels are shown to be in compliance with the typically accepted daytime noise limit of 75 dBA, the following mitigation measures should still be practiced as a courtesy to residential neighbors.

1. Construction activity must be limited to the hours of 7 a.m. to 6 p.m., Mondays through Fridays, and 8 a.m. to 5 p.m., on Saturdays, as per the City of San Marcos Municipal Code.

2. Staging areas should be placed as far from occupied receivers as possible on the project site to limit any additional unnecessary noise exposure at sensitive receivers.

3. Place stationary equipment in locations that will have a lesser noise impact on nearby sensitive receivers.

4. Turn off equipment when not in use.

5. Limit the use of enunciators or public address systems, except for emergency notifications.

6. Equipment used in construction should be maintained in proper operating condition, and all loads should be properly secured, to prevent rattling and banging.

7. Schedule work to avoid simultaneous construction activities that both generate high noise levels.

8. Use equipment with effective mufflers.

9. Minimize the use of backup alarms.

With work limited to those allowable by the City of San Marcos, temporary construction noise will not exceed the applicable thresholds of the City of San Marcos Municipal Code.

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_______________________________________________________________________________

6.0 CONCLUSION

The City of San Marcos Noise Element to the General Plan states that exterior noise levels of single- family residential land uses should not exceed 60 CNEL in order to be considered “acceptable.” A noise analysis was performed to determine anticipated future traffic noise impacts at facades and proposed private outdoor use areas (backyards) of lots on the project site. Future noise calculations show that, without mitigation, on-site traffic noise levels are expected to exceed 60 CNEL. For this reason, six-foot high sound barrier walls have been proposed that would allow noise levels to be reduced to below 60 CNEL at outdoor use areas.

A sound attenuation wall should be solid and constructed of masonry, wood, plastic, fiberglass, steel, or a combination of those materials, with no cracks or gaps, through or below the wall. Any seams or cracks must be filled or caulked as much as possible. If wood is used, it can be tongue and groove and must be at least 7/8-inch thick or have a surface density of at least 3-1/2 pounds per square foot.

Where architectural or aesthetic factors allow, glass or clear plastic may be used on the upper portion, if it is desirable to preserve a view. A glass or plexiglass railing wall at specified patios and balconies should be sufficient in these locations.

The City of San Marcos and the State of California require interior noise levels of 45 CNEL or less in residences. Calculations show that future noise levels on site exceed 60 CNEL at most of the lots on site. A preliminary analysis of interior noise levels demonstrates that residences on site are expected to comply with interior noise requirements with standard construction in place and the implementation of mechanical ventilation systems.

Calculations show that noise levels generated by anticipated HVAC units are expected to meet the applicable noise limits at surrounding property lines, as currently designed. No added project design features are deemed necessary for attenuating these mechanical noise impacts.

The City of San Marcos Municipal Code restricts the operation of construction equipment to the hours of 7 a.m. to 6 p.m., Mondays through Fridays, and 8 a.m. to 5 p.m. on Saturdays. Noise from temporary construction activities is not expected to exceed typical noise limits at any surrounding property lines. Standard construction noise control methods including adhering to permissible hours of operation, maintaining equipment in proper operating condition, and placing staging areas at furthest locations from noise sensitive receivers are expected to be sufficient for reducing noise impacts to surrounding receivers.

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_______________________________________________________________________________

7.0 CERTIFICATION

All recommendations for noise control are based on the best information available at the time our consulting services are provided. However, as there are many factors involved in sound transmission, and Eilar Associates has no control over the construction, workmanship or materials, Eilar Associates is specifically not liable for final results of any recommendations or implementation of the recommendations.

This report is based on the related project information received and measured noise levels, and represents a true and factual analysis of the acoustical issues associated with 2110 Montiel Road Tentative Map No. 14-006, to be located on Montiel Road in the City of San Marcos, California. This report was prepared by Daniel Gershun and Mo Ouwenga.

________________________________________ ____________________________________

Daniel Gershun, Acoustical Consultant II Mo Ouwenga, Staff Consultant

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_______________________________________________________________________________

8.0 REFERENCES

1. Beranek, Leo L., Acoustical Measurements, Published for the Acoustical Society of America by the American Institute of Physics, Revised Edition, 1988.

2. City of San Marcos Municipal Code.

3. City of San Marcos Noise Element to the General Plan.

4. Harris, Cyril M., Handbook of Acoustical Measurements and Noise Control, Acoustical Society of America, 3^rd Edition, 1998.

5. Harris, Cyril M., Ph.D., Noise Control in Buildings, Original Edition, 1994.

6. Hirschorn, Martin, Noise Control Reference Handbook, Revised Edition, 1989.

7. Irvine, Leland K. and Richards, Roy L., Acoustics and Noise Control Handbook for Architects and Builders, Original Edition, 1998.

8. Knudsen, Vern O. and Harris, Cyril M., Acoustical Designing In Architecture, American Institute of Physics for the Acoustical Society of America, 2^nd Edition, 1978.

9. Raichel, Daniel R., The Science and Applications of Acoustics, American Institute of Physics Press for the Acoustical Society of America, 1^st Edition, 2000.

10. Wyle Laboratories, Development of Ground Transportation Systems Noise Contours for the San Diego Region, December, 1973

11. Traffic Distribution Study, by Katz-Okitsu and Associates Traffic Engineers, 1986.

12. Department for Environment Food and Rural Affairs (DEFRA), Update of Noise Database for Prediction of Noise on Construction and Open Sites, 2005.

13. Federal Highway Administration, Highway Traffic Noise: Analysis and Abatement Guide, December 2011.

14. Whitson, Kent A., SANTEC / ITE Guidelines for Traffic Impact Studies [TIS] in the San Diego Region, March 2000.

15. U.S. Environmental Protection Agency Office of Noise Abatement and Control, Information on Levels of Environmental Noise Requisite to Protect Public Health and Welfare With an Adequate Margin of Safety , March 1974.

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FIGURES

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Vicinity Map Job # B70206N1

210 South Juniper Street, Suite 100 Escondido, California 92025

760-738-5570

N

Figure 1 Project

Location

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760-738-5570

N

Figure 2 Assessor’s Parcel Map

Job # B70206N1

2281200900 2281203400

Project Location San Diego County

Assessor’s Parcel Numbers:

228-120-09-00

228-120-34-00

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760-738-5570

N

Figure 3 Satellite Aerial Photograph

Job # B70206N1

Project

Location

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Topographic Map Job # B70206N1

760-738-5570

Figure 4

N

Project

Location

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210 South Juniper Street, Suite 100 Escondido, California

760-738-5570

Figure 5 Site Plan Showing Current Traffic CNEL

Contours and Noise Measurement Location Job # B70206N1

N

Noise Measurement

Location

65 CNEL Contour

70 CNEL Contour

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Eilar Associates, Inc.

210 South Juniper Street, Suite 100 Escondido, California

760-738-5570

Figure 6 Site Plan Showing Future Traffic CNEL

Contours and Noise Measurement Location Job # B70206N1

N

Noise Measurement

Location

65 CNEL Contour

70 CNEL Contour

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Figure 7 Site Plan Showing Future Traffic CNEL Impacts

at Outdoor Use Areas with Barrier Walls B70206N1

N

210 South Juniper Street, Suite 100 Escondido, California 92025

760-738-5570 OU-1 OU-2

OU-3 OU-4 OU-5

OU-6

OU-7

OU-8

OU-9

= 6’ High Barrier Wall

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F1

Figure 8 Site Plan Showing Future Traffic CNEL

Impacts at Building Facades Job # B70206N1

N

760-738-5570

F14

F2

F3 F4

F5

F6 F7

F8

F9

F11 F12

F15 F16

F13

F18 F19

F20

F17

F22 F23

F24

F21

F26 F27

F28

F25

F30 F31

F32

F29

F34 F35

F36

F33

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R10 R9

R8 R7

R11

R12 R1

R2 R3

R4 R5

N

R6

Legend

3-ton Unit 4-ton Unit

Receiver Locations

760-738-5570

Satellite Aerial Photograph Showing Mechanical Equipment Noise Contours

and Receiver Locations Job # B70206N1

Figure 9

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210 South Juniper Street, Suite 100 Escondido, California

760-738-5570

Figure 10 Satellite Aerial Photograph Showing

Construction Noise Source and Receiver Locations

Job # B70206N1

N

Construction Noise Source Location

Residential Receiver Location- South Residential Receiver

Location- West

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APPENDIX A

Project Plans

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APPENDIX B

Pertinent Sections of the City of San Marcos

Noise Element to the General Plan and Municipal Code

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McClellan-Palomar Airport is 2.5 miles from San Marcos. 65dbl contours from the airport do not reach the City.

Photo credit: AECOM

7

noise element

City of San Marcos General Plan | Noise | Page 7-10

The City’s updated land use compatibility standards for this Element (Table 7-3) are based first on the General Plan land use designation of the property and secondly on the use of the property. For example, within the Residential land use designation, a multiple-family use exposed to transportation related noise would have an exterior noise standard of 60 dBA CNEL/

Ldn. Noise standards for multiple-family and mixed-use land use designations shown in Table 7-4 are higher than those for single-family residential areas reflecting a more urban environment planned for certain areas of the City. The standards shown in Table 7-3 are purposefully general in nature and not every land use type which could be accommodated within each General Plan designation is identified. Application of the noise standards will vary on a case-by-case basis according to location, development type, and associated noise sources.

Table 7-3

Noise and Land Use Compatibility Guidelines for Transportation-related Noise

Exterior Noise Level (CNEL) Land Use Category

A Residential—single family residences, mobile homes, senior/age-restricted housing

B Residential—multifamily residences, mixed use (residential/commercial)

C Lodging—hotels, motels

D² Schools, churches, hospitals, residential care facility, child care facilities

E² Passive recreational parks, nature preserves, contemplative spaces, cemeteries

F² Active parks, golf courses, athletic fields, outdoor spectator sports, water recreation

G² Office/professional, government, medical/dental, commercial, retail, laboratories

H²

Industrial, manufacturing, utilities, agriculture, mining, stables, ranching, warehouse, mainte- nance/repair

Acceptable - Specified land use is satisfactory, based upon the assumption that any buildings involved Conditionally Acceptable - New construction or development should be undertaken only after a detailed noise analysis is conducted to determine if noise reduction measures are necessary to achieve acceptable levels for land use. Criteria for determining exterior and interior noise levels are listed in Table 7-4, Noise Standards. If a project cannot mitigate noise to a level deemed Acceptable, the appropriate County decision-maker must determine that mitigation has been provided to the greatest extent practicable or that extraordinary circumstances exist.

Unacceptable - New construction or development shall not be undertaken.

55 60 65 70 75 80

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7

noise element

City of San Marcos General Plan | Noise | Page 7-11

Table 7-4

Noise Standards⁽¹⁾

1. The exterior noise level (as defined in Item 3) standard for Category A shall be 60 CNEL, and the interior noise level standard for indoor habitable rooms shall be 45 CNEL.

2. The exterior noise level standard for Categories B and C shall be 65 CNEL, and the interior noise level standard for indoor habitable rooms shall be 45 CNEL.

3. The exterior noise level standard for Categories D and G shall be 65 CNEL and the interior noise level standard shall be 50 dBA Leq (one hour average).

4. For single-family detached dwelling units, “exterior noise level” is defined as the noise level measured at an outdoor living area which adjoins and is on the same lot as the dwelling, and which contains at least the following minimum net lot area: (i) for lots less than 4,000 square feet in area, the exterior area shall include 400 square feet, (ii) for lots between 4,000 square feet to 10 acres in area, the exterior area shall include 10 percent of the lot area; (iii) for lots over 10 acres in area, the exterior area shall include 1 acre.

5. For all other residential land uses, “exterior noise level” is defined as noise measured at exterior areas which are provided for private or group usable open space purposes. “Private Usable Open Space” is defined as usable open space intended for use of occupants of one dwelling unit, normally including yards, decks, and balconies. When the noise limit for Private Usable Open Space cannot be met, then a Group Usable Open Space that meets the exterior noise level standard shall be provided. “Group Usable Open Space” is defined as usable open space intended for common use by occupants of a development, either privately owned and maintained or dedicated to a public agency, normally including swimming pools, recreation courts, patios, open landscaped areas, and greenbelts with pedestrian walkways and eques- trian and bicycle trails, but not including off-street parking and loading areas or driveways

6. For non-residential noise sensitive land uses, exterior noise level is defined as noise measured at the exterior area provided for public use.

7. For noise sensitive land uses where people normally do not sleep at night, the exterior and interior noise standard may be measured using either CNEL or the one-hour average noise level determined at the loudest hour during the period when the facility is normally occupied.

8. The exterior noise standard does not apply for land uses where no exterior use area is proposed or necessary, such as a library.

9. For Categories E and F the exterior noise level standard shall not exceed the limit defined as “Accept- able” in by the City, or an equivalent one-hour noise standard.

(1) Exterior Noise Level compatibility guidelines for Land Use Categories A-H are identified in Table 3.11-6, Noise Compatibility Guidelines.

Note: “Category(ies)” discussed in this table refer to lettered Land Use Category(ies) in Table 7-3 of this Element.

Noise Contours and Impacted Areas

Noise contours, based on the location of major noise sources, describe the ambient noise environment within the community. These contours outline areas of equal noise exposure.

Information about existing and projected land use development and transportation activity has been used to estimate future noise contours for San Marcos, which are illustrated in Figure 7-2.

Noise contours are not shown for all streets or street segments as contours are based on traffic generation ADT/LOS analysis data.

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San Marcos Municipal Code Title 20 – Zoning Ordinance

Chapter 20.300 Site Planning and General Development Standards

20.300-12 Table 20.300-4 Noise Standar ds by Zone

Zone

Allowable Noise Level (dBA) Measured from the

Property Line Single-Family Residential (A, R-1, R-2)

7 a.m. to 10 p.m. (daytime) 60 10 p.m. to 7 a.m. (overnight) 50 Multifamily Residential (R-3)

7 a.m. to 10 p.m. (daytime) 65 10 p.m. to 7 a.m. (overnight) 55 Commercial (C, O-P, SR)

7 a.m. to 10 p.m. (daytime) 60 10 p.m. to 7 a.m. (overnight) 55 Industrial

7 a.m. to 10 p.m. (daytime) 65 10 p.m. to 7 a.m. (overnight) 60

3. No person shall create nor allow the creation of noise that causes the interior noise level when measured within a dwelling unit to exceed forty-five (45) dBA at any time, except as permitted by Table 20.300-6.

4. Use of compressors or other equipment, including vents, ducts, and conduits, but excluding window or wall‐mounted air‐conditioners, that are located outside of the exterior walls of any building, shall be enclosed within a permanent, non-combustible, view‐obscuring enclosure to ensure that the equipment does not emit noise in excess of the ANSI standards.

Table 20.300-5

Per mitted Incr ease in Noise Levels

Permitted Increase (dBA)

Duration (cumulative minutes per hour)

5 15

10 5

15 1

20 Less than 1 minute

Table 20.300-6 Per mitted Incr ease in

Inter ior Noise Levels

Permitted Increase (dBA)

Duration (cumulative minutes per hour)

5 1

10 Less than 1 minute

G. Vibration. Vibration may disturb the conduct of certain activities and create discomfort for some individuals. To minimize the disturbance and inconvenience from vibrations, no person or use shall create, maintain, or cause ground vibration that is discernible without instruments to a person of normal sensitivity at any point on a property that is adjacent to the property of the vibration source. The ground vibration caused by moving vehicles, trains, aircraft, or temporary construction or demolition is exempted.

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