N-1(b) Vehicle and Equipment Idling. Construction vehicles and equipment shall not be left idling for longer than five minutes when not in use.

Transcription

1 4.10 NOISE Summary Table summarizes the identified environmental impacts, proposed mitigation measures, and residual impacts of the proposed project with regard to noise. Additional detail is provided in Section (Impact Analysis). Table Impact and Mitigation Summary: Noise Impact Mitigation Measures Residual Impact Impact N-1 Noise from demolition of existing structures, excavation and grading, and construction of the project and associated infrastructure has the potential to adversely impact existing and future nearby residences. Impacts would be Class II, significant but mitigable. N-1(a) Construction Equipment. Construction equipment shall be properly maintained and all internal combustion engine driven machinery with intake and exhaust mufflers and engine shrouds, as applicable, shall be in good condition and appropriate for the equipment. Equipment engine shrouds shall be closed during equipment operation. Whenever feasible, electrical power shall be used to run air compressors and similar power tools rather than diesel equipment. The developer shall require all contractors, as a condition of contract, to maintain and tune-up all construction equipment to minimize noise emissions. N-1(b) Vehicle and Equipment Idling. Construction vehicles and equipment shall not be left idling for longer than five minutes when not in use. N-1(c) Stationary Equipment. Stationary construction equipment that generates noise that exceeds 60 dba Leq at the boundaries of the nearby residential uses shall be shielded. Temporary noise barriers used during construction activity shall be made of noise-resistant material sufficient to achieve a Sound Transmission Class (STC) rating of STC 40 or greater, based on sound transmission loss data taken according to ASTM Test Method E90. Such a barrier may provide as much as a 10 db insertion loss, provided it is positioned as close as possible to the noise source or to the receptors. To be effective, the barrier must be long and tall enough (a minimum height of eight feet) to completely block the line-ofsight between the noise source and Implementation of Mitigation Measures N-1(a) through N-1(e) would reduce construction noise impacts to a less than significant level

2 Table Impact and Mitigation Summary: Noise Impact Mitigation Measures Residual Impact the receptors. The gaps between adjacent panels must be filled-in to avoid having noise penetrate directly through the barrier. The recommended minimum noise barrier or sound blanket requirements would reduce construction noise levels by at least 10 db. The equipment area with appropriate acoustical shielding shall be designated on building and grading plans. Equipment and shielding shall remain in the designated location throughout construction activities. Prior to issuance of grading permits, the project proponent shall submit building and grading plans that show the appropriate construction equipment noise reduction measures to the RMA Planning Department. Compliance shall be monitored by County Building Inspectors. N-1(d) Workers Radios. All noise from workers radios shall be controlled to a point that they are not audible at sensitive receptors near the construction activity. N-1(e) Disturbance Coordinator. A noise disturbance coordinator shall be designated by the contractor. The noise disturbance coordinator shall be responsible for responding to any local complaints about construction noise. The noise disturbance coordinator shall determine the cause of the noise complaint (e.g., starting too early, bad muffler, etc.) and shall require that reasonable measures warranted to correct the problem be implemented. A telephone number for the disturbance coordinator shall be conspicuously posted at the construction site

3 Table Impact and Mitigation Summary: Noise Impact Mitigation Measures Residual Impact Impact N-2 Construction-related activities associated with the proposed project would intermittently generate groundborne vibration on and adjacent to the site. This may affect existing off-site receptors near the project site and proposed on-site residences, but would not create vibrations that could cause structural damage to adjacent structures within 100 feet of the project site. Impacts would be Class III, less than significant. No mitigation is required. Impact N-3 Occupants of proposed on-site and existing off-site residential units would not experience noise level increases exceeding applicable thresholds as a result of project-generated traffic on Highway 1, Carmel Valley Road, Val Verde Drive, Rio Road, or Carmel Rancho Boulevard. Projectgenerated traffic would have a less than significant impact on exterior and interior noise levels at existing and proposed sensitive receptors on Val Verde Drive. Impacts would be Class III, less than significant. Impact N-4 The proposed residential uses would be subject to operational noise generated from existing commercial operations west of the site, as well as noise generated from outdoor activities and operations on nearby school playgrounds. However, noise generated by these uses would not exceed applicable standards. The project would also generate additional noise from operation of the proposed residential uses. These noise impacts would not cause the applicable standards to be exceeded for any nearby uses. Impacts would be Class II, less than significant Environmental Setting No mitigation is required. No mitigation is required. Impacts would be less than significant without mitigation. Impacts would be less than significant without mitigation. Impacts would be less than significant without mitigation. a. Overview of Noise. Noise level (or volume) is generally measured in decibels (db) using the A-weighted sound pressure level (dba). The A-weighting scale is an adjustment to the actual sound pressure levels to be consistent with that of human hearing response, which is most sensitive to frequencies around 4,000 Hertz (about the highest note on a piano) and less sensitive to low frequencies (below 100 Hertz)

4 Sound pressure level is measured on a logarithmic scale with the 0 db level based on the lowest detectable sound pressure level that people can perceive (an audible sound that is not zero sound pressure level). Based on the logarithmic scale, a doubling of sound energy is equivalent to an increase of 3 dba, and a sound that is 10 dba less than the ambient sound level has no effect on ambient noise. Because of the nature of the human ear, a sound must be about 10 dba greater than the reference sound to be judged as twice as loud. In general, a 3 dba change in community noise levels is noticeable, while 1-2 db changes generally are not perceived. Quiet suburban areas typically have noise levels in the range of dba, while arterial streets are in the dba range. Normal conversational levels are in the dba range, and ambient noise levels greater than 65 dba can interrupt conversations. Noise levels typically attenuate (or drop off) at a rate of 6 dba per doubling of distance from point sources (such as industrial machinery). Noise from lightly traveled roads typically attenuates at a rate of about 4.5 dba per doubling of distance. Noise from heavily traveled roads typically attenuates at about 3 dba per doubling of distance. Noise levels may also be reduced by intervening structures; generally, a single row of buildings between the receptor and the noise source reduces the noise level by about 5 dba, while a solid wall or berm reduces noise levels by 5 to 10 dba. The manner in which older homes in California were constructed (approximately 30 years old or older) generally provides a reduction of exterior-to-interior noise levels of about 20 to 25 dba with closed windows. The exterior-to-interior reduction of newer residential units and office buildings is generally 30 dba or more (FTA, 2006). In addition to the actual instantaneous measurement of sound levels, the duration of sound is important since sounds that occur over a long period of time are more likely to be an annoyance or cause direct physical damage or environmental stress. One of the most frequently used noise metrics that considers both duration and sound power level is the equivalent noise level (Leq). The Leq is defined as the single steady A-weighted level that is equivalent to the same amount of energy as that contained in the actual fluctuating levels over a period of time (essentially, the average noise level). Typically, Leq is summed over a one-hour period. Lmax is the highest RMS (root mean squared) sound pressure level within the measuring period, and Lmin is the lowest RMS sound pressure level within the measuring period. The time period in which noise occurs is also important since noise that occurs at night tends to be more disturbing than that which occurs during the day. Community noise is usually measured using Day-Night Average Level (Ldn), which is the 24-hour average noise level with a 10-dBA penalty for noise occurring during nighttime (10 p.m. to 7 a.m.) hours, or Community Noise Equivalent Level (CNEL), which is the 24-hour average noise level with a 5 dba penalty for noise occurring from 7 p.m. to 10 p.m. and a 10 dba penalty for noise occurring from 10 p.m. to 7 a.m. Noise levels described by Ldn and CNEL usually do not differ by more than 1 db. b. Fundamentals of Groundborne Vibration. Vibration is sound radiated through the ground. The rumbling sound caused by the vibration of room surfaces is called groundborne noise. The ground motion caused by vibration is measured as particle velocity in inches per second and, in the U.S., is referenced as vibration decibels (VdB). The background vibration velocity level in residential areas is usually around 50 VdB. The vibration velocity level threshold of perception for humans is approximately 65 VdB. According

5 to the Federal Transit Administration Transit and Noise Vibration Impact Assessment (May 2006), a vibration velocity level of 75 VdB is the approximate dividing line between barely perceptible and distinctly perceptible levels for many people. Most perceptible indoor vibration is caused by sources within buildings, such as operation of mechanical equipment, movement of people, or the slamming of doors. Typical outdoor sources of perceptible groundborne vibration are construction equipment, steel-wheeled trains, and traffic on rough roads. If a roadway is smooth, the groundborne vibration from traffic is rarely perceptible. The range of interest is from approximately 50 VdB, which is the typical background vibration velocity level, to 100 VdB, which is the general threshold where minor damage can occur in fragile buildings. The general human response to different levels of groundborne vibration velocity levels is described in Table Table Human Response to Different Levels of Groundborne Vibration Vibration Velocity Level Human Reaction 65 VdB Approximate threshold of perception for many people. 75 VdB 85 VdB Approximate dividing line between barely perceptible and distinctly perceptible. Many people find transit vibration at this level annoying. Vibration acceptable only if there are an infrequent number of events per day. 90 VdB Difficulty with tasks such as reading computer screens. Source: FTA, 2006 c. Sensitive Receptors. Noise exposure goals for various types of land uses reflect the varying noise sensitivities associated with each of these uses. The 2010 General Plan Noise Element, which is contained in the General Plan Safety Element, identifies normally acceptable, conditionally acceptable, normally unacceptable, and clearly unacceptable noise levels for a variety of land use and development types, based on the Office of Planning and Research (OPR) General Plan Guidelines. The most noise sensitive land uses include residences, hotels, schools, libraries, churches, hospitals, and nursing homes. Sensitive receptors near the project site include those on land adjacent to the north, south, and east side designated Low Density Residential that currently have existing residences or could in the future. The existing residences are located 50 feet from the northern and southern project site boundaries. d. Existing Noise Levels. The proposed project would be built and operated on an approximately 7.9-acre parcel that would be subdivided into 25 lots. The general noise environment of the project area is characterized by open space, rural residential, or agricultural uses with low ambient noise levels during the evening and nighttime hours. The primary ambient sources of noise on the project site and in the surrounding area include wind and fauna such as birds and small mammals. Noise generators during the day include those typically associated with minor agricultural activities and local passenger and heavy-duty truck traffic along the nearest major roadways to the project site: Carmel Valley Road, located 1,050 feet to

6 the north; State Route (Highway) 1, located 1,370 feet to the west; and Carmel Rancho Boulevard, located 180 feet to the west. Rio Road and Val Verde Drive are the two local roads providing access to the site. Rio Road is located 300 feet south of the site and connects to Val Verde Drive, a private drive that runs adjacent to the project s eastern boundary. These two roadways carry limited traffic and therefore are not substantial sources of noise. Motor vehicle noise can be of concern because it is characterized by a high number of individual events, which often create a sustained noise level. Land forms and man-made structures have complex effects on sound transmission and on noise contours. Generally, barriers between a source and receiver absorb or reflect noise resulting in a quieter environment. Where barriers or land forms do not interrupt the noise transmission path from source to receiver, the contours prove to be good estimates of the average noise level from roadway traffic. In areas where barriers or land forms interrupt the sound transmission, the noise contours overestimate the extent to which a source intrudes into the community. The Monterey County General Plan noise contour distances, as shown in Figure 10C in the General Plan, depict worst-case conditions because they do not account for any obstructions to the noise path, such as walls, berms, or buildings. The 2010 General Plan Noise Element provides existing and projected noise contours associated with airports, stationary sources, and roadway sources, which provide a visualization of estimates of sound level. The project site is not within any identified noise contour in the 2010 General Plan for Highway 1, Carmel Valley Road, Carmel Rancho Boulevard, or Rio Road, indicating that ambient noise levels on the project site are generally below 50 dba. Noise measurements taken at the site, shown in Table , indicated similar levels. Measurement Location Station A: Fifteen feet west of Val Verde Drive, approximately 200 feet south of northern boundary Station B: Twenty-five feet from western boundary, approximately 200 feet south of northern boundary Table Sound Level Measurement Results (dba) Primary Noise Source Vehicle traffic on Val Verde Drive, Carmel Valley Road, and Highway 1 Vehicle traffic on Carmel Rancho Blvd. and adjacent parking lot Source: Field visit using ANSI Type II Integrating sound level meter. See Appendix H for sound level measurement data sheets Sample Time 11/14/2015 4:25 p.m. 4:40 p.m. 11/14/2015 4:50 p.m. 5:05 p.m. Leq Measured Lmax Lmin e. Regulatory Setting. Federal. Under the Occupational Safety and Health Act of 1970 (29 U.S.C. 651 et seq.), the United States Department of Labor, Occupational Safety and Health Administration (OSHA) adopted regulations (29 CFR ) designed to protect workers against the effects of occupational noise exposure. These regulations list limits on noise exposure levels as a function of the amount of time during which the worker is exposed, as shown in Table

7 The regulations further specify requirements for a hearing conservation program ( (c)), a monitoring program ( (d)), an audiometric testing (i.e., test of hearing ability) program ( (g)), and hearing protection ( (i)). There are no federal laws governing community noise. Table OSHA Permissible Noise Exposure Standards Duration of Noise (Hours/Day) A-Weighted Noise Level (dba) or less 115 Source: 29 CFR , Table G-16. State. California Government Code encourages each local government entity to implement a noise element as part of its general plan. In addition, OPR has developed guidelines for preparing noise elements, which include recommendations for evaluating the compatibility of various land uses as a function of community noise exposure.. The 2010 General Plan Noise Element identifies normally acceptable, conditionally acceptable, normally unacceptable, and clearly unacceptable noise levels for a variety of land use and development types, based on OPR General Plan Guidelines. Figure shows the community noise exposure levels. The 2010 General Plan Noise Element also includes policies that are designed to meet General Plan Goal S-7, to maintain a healthy and quiet environment free from annoying and harmful sounds. These policies address requirements for new noisesensitive land uses, development in areas that may be exposed to high levels of noise, construction of new noise-generating uses, procedures for acoustical analysis and environmental review, regulations for construction activity and the use of heavy construction equipment, and standard noise protection measures for new construction. In addition to applicable General Plan policies, Title 24 of the California Health and Safety Code establishes an interior noise standard of 45 dba for residential units

8 Source: 2010 Monterey County General Plan Monterey County Community Noise Exposure Ldn or CNEL, db Figure

9 The Monterey County Code, Chapter Noise Control, also regulates noise. Section states, This Board finds that noises generated so as to be in excess of the levels permitted in this Chapter impair hearing, impede convalescence, hinder concentrated mental effort, interfere with relaxation and sleep, depreciate property values, and cause stress and nervous tension and consequent irritability, insomnia, accident proneness, and increased risk for cardiovascular disease and hypertension. Section prohibits operating anything that exceeds a noise level of 85 dba measured 50 feet therefrom. Section regulates nighttime noise levels, defined as between the hours of 10:00 p.m. to 7:00 a.m. the next morning. The maximum nighttime hourly equivalent sound level (Leq dba) is 45 and the maximum dba is Impact Analysis a. Methodology and Significance Thresholds. Methodology. The analysis of noise impacts considers the effects of both temporary construction-related noise, including demolition of the existing residence on the project site and construction activities, and operational noise associated with long-term project-related activities, including project-generated traffic as well as stationary source noise. Construction noise estimates are based upon noise levels reported by the Federal Transit Administration (FTA), Office of Planning and Environment (FTA, 2006), and the distance to nearby sensitive receptors. Reference noise levels from that document were then used to estimate noise levels at nearby sensitive receptors based on a standard noise attenuation rate of 6 db per doubling of distance, which is the line-of-sight method of sound attenuation for point sources of noise. Construction noise level estimates do not account for the presence of intervening structures or topography, which could reduce noise levels at receptor locations. Therefore, the noise levels presented herein represent a conservative, reasonable worst-case estimate of actual construction noise. The maximum community noise exposure levels shown in Figure and applicable County General Plan Noise Element policies were used to determine whether noise generated during the project construction or operational phases would result in a significant impact on nearby sensitive receptors. Significance Thresholds. Pursuant to Appendix G of the State CEQA Guidelines, potentially significant impacts would occur if the project would result in any of the following conditions: 1. Exposure of persons to or generation of noise levels in excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies; 2. Exposure of persons to or generation of excessive ground-borne vibration or groundborne noise levels; 3. A substantial permanent increase in ambient noise levels in the project vicinity above levels existing without the project; 4. A substantial temporary or periodic increase in ambient noise levels in the project vicinity above levels existing without the project; 5. For a project located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the project expose people residing or working in the project area to excessive noise levels; and/or

10 6. For a project within the vicinity of a private airstrip, would the project expose people residing or working in the project area to excessive noise levels. The project site is not located within any airport noise impact contours and would therefore not expose residents or workers to excessive noise levels from airport or private air strip operations. Further discussion regarding thresholds 5 and 6 can be found in Section 4.14, Effects Found not to be Significant. For traffic-related noise, impacts are considered significant if project-generated traffic would result in exposure of sensitive receptors to an unacceptable increase in noise levels. Recommendations contained in the Transit Noise and Vibration Impact Assessment (FTA, 2006) were used to determine whether increases in traffic noise would be unacceptable. With these standards, the allowable noise exposure increase is reduced with increasing ambient existing noise exposure, such that higher ambient noise levels have a lower allowable noise exposure increase. Table shows the significance thresholds for increases in traffic-related noise levels caused by the project. Table Significance of Changes in Operational Roadway Noise Exposure Existing Noise Exposure (dba Ldn or Leq) Allowable Noise Exposure Increase (dba Ldn or Leq) Source: FTA, If sensitive receptors would be exposed to traffic noise increases exceeding the above criteria, impacts would be considered significant. Impacts related to on-site activities, such as noise from construction activity, would be considered significant if project activities would result in noise levels exceeding 60 db Ldn or CNEL as shown in the community noise exposure levels, as depicted in Figure , or conflict with applicable County General Plan Noise Element policies. Policy S-7.7 requires a noise impact analysis for projects within the 60 CNEL roadway or railroad noise contours

11 b. Project Impacts and Mitigation Measures. Threshold 1: Threshold 4: Impact N-1 Exposure of persons to or generation of noise levels in excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies. A substantial temporary or periodic increase in ambient noise levels in the project vicinity above levels existing without the project. Noise from demolition of existing structures, excavation and grading, and construction of the project and associated infrastructure has the potential to adversely impact existing and future nearby residences. Impacts would be Class II, significant but mitigable. The main sources of noise during construction activities would include heavy machinery used in demolition, grading, and clearing the site, as well as equipment used during building construction and paving, creating temporary or periodic increases in ambient noise. Table demonstrates the typical noise levels associated with heavy construction equipment. Based on the type of construction required and the generally flat topography of the site, this list of equipment is appropriate for the proposed project. As shown in Table , average noise levels associated with the use of heavy equipment at construction sites can reach up to 89 dba at 50 feet from the source. The heaviest equipment use would occur during construction of the proposed on-site looped road, including placement of sewer and other utilities within the right-of-way. Construction of the individual houses would also be a source of noise, mainly during framing with the use of air compressors and nail guns and no structure in place to reduce sound travel. Table Typical Construction Equipment Noise Levels Typical Maximum Noise Level (dba) Equipment 50 Feet from the Source 70 Feet from the Source 170 Feet from the Source 200 Feet from the Source Air Compressor Backhoe Paver Concrete Mixer Dozer Jack Hammer Roller Grader Scraper Truck Source: Table 12-1 in FRA, Noise levels based on actual maximum measured noise levels at 50 feet (Lmax). Noise levels assume a noise attenuation rate of 6 dba per doubling of distance

12 The two nearest existing residences are north and south of the project site, the closest being 50 feet from the project boundary. These receptors could be as close as 50 feet from grading activities, 70 feet from house construction (due to the required 20-foot rear building setback), and 170 to 200 feet from construction of the internal looped roadway. If new residences are constructed and occupied prior to completion of all on-site construction, these future residences would also be located in close proximity to construction activities. Based on the noise levels shown in Table , site grading within 50 feet of residences could result in noise levels of up to 89 dba. At a distance of 70 feet, noise levels of 84 dba for a jack hammer and 77 dba for an air compressor, which the most typical equipment used for house construction, could occur. The maximum noise exposure level from road construction equipment is estimated at 75 dba at a distance of 170 feet. Depending on the duration and timing of construction activity, maximum noise levels at nearby receptors may result in an exceedance of the County s 60 dba CNEL standard for residential receptors. Therefore, the existing residences nearest to the project site and future residences on the project site may experience unacceptable noise levels during project construction, which is estimated to last approximately 18 months. Monterey County General Plan Safety Element noise Policies S-7.9 and S-7.10 address construction noise impacts by restricting hours of operation and requiring standard noise protection measures: S-7.9 No construction activities pursuant to a County permit that exceed acceptable levels listed in Policy S-7.1 shall be allowed within 500 feet of a noise sensitive land use during the evening hours of Monday through Saturday, or anytime on Sunday or holidays, prior to completion of a noise mitigation study. Noise protection measures, in the event of any identified impact, may include but not be limited to: Constructing temporary barriers, or Using quieter equipment than normal S-7.10 Construction projects shall include the following standard noise protection measures: Construction shall occur only during times allowed by ordinance/code unless such limits are waived for public convenience; All equipment shall have properly operating mufflers; and Lay-down yards and semi-stationary equipment such as pumps or generators shall be located as far from noise-sensitive land uses as practical. Monterey County Code Chapter sets nighttime noise limits to 45 Leq dba and a maximum dba of 65 between the hours of 10:00 p.m. to 7:00 a.m. The County General Plan has tighter restrictions on construction noise, limiting construction on weekdays and Saturdays before sundown and not on Sundays to reduce noise impacts, therefore, the County Code requirements are being addressed through adherence to the County General Plan. The County has requirements for reducing construction noise, as shown above, but because of the potential noise exposure estimated above, additional mitigation is necessary to reduce those impacts to a less than significant level

13 Mitigation Measures. Noise-generating construction activities would be restricted by the 2010 General Plan to weekdays and Saturday before sundown, and not allowed on Sunday. Compliance with these requirements would partially limit construction-related noise impacts. The following measures are also required. N-1(a) N-1(b) N-1(c) Construction Equipment. Construction equipment shall be properly maintained and all internal combustion engine driven machinery with intake and exhaust mufflers and engine shrouds, as applicable, shall be in good condition and appropriate for the equipment. Equipment engine shrouds shall be closed during equipment operation. Whenever feasible, electrical power shall be used to run air compressors and similar power tools rather than diesel equipment. The developer shall require all contractors, as a condition of contract, to maintain and tune-up all construction equipment to minimize noise emissions. Vehicle and Equipment Idling. Construction vehicles and equipment shall not be left idling for longer than five minutes when not in use. Stationary Equipment. Stationary construction equipment that generates noise that exceeds 60 dba Leq at the boundaries of the nearby residential uses shall be shielded. Temporary noise barriers used during construction activity shall be made of noiseresistant material sufficient to achieve a Sound Transmission Class (STC) rating of STC 40 or greater, based on sound transmission loss data taken according to ASTM Test Method E90. Such a barrier may provide as much as a 10 db insertion loss, provided it is positioned as close as possible to the noise source or to the receptors. To be effective, the barrier must be long and tall enough (a minimum height of eight feet) to completely block the line-ofsight between the noise source and the receptors. The gaps between adjacent panels must be filled-in to avoid having noise penetrate directly through the barrier. The recommended minimum noise barrier or sound blanket requirements would reduce construction noise levels by at least 10 db. The equipment area with appropriate acoustical shielding shall be designated on building and grading plans. Equipment and shielding shall remain in the designated location throughout construction activities. Prior to issuance of grading permits, the project proponent shall submit building and grading plans that show the appropriate construction equipment noise reduction measures to the RMA Planning Department. Compliance shall be monitored by County Building Inspectors

14 N-1(d) N-1(e) Workers Radios. All noise from workers radios shall be controlled to a point that they are not audible at sensitive receptors near the construction activity. Disturbance Coordinator. A noise disturbance coordinator shall be designated by the contractor. The noise disturbance coordinator shall be responsible for responding to any local complaints about construction noise. The noise disturbance coordinator shall determine the cause of the noise complaint (e.g., starting too early, bad muffler, etc.) and shall require that reasonable measures warranted to correct the problem be implemented. A telephone number for the disturbance coordinator shall be conspicuously posted at the construction site. Significance After Mitigation. Implementation of Mitigation Measures N-1(a) through N-1(e) would reduce construction noise impacts to a less than significant level. Threshold 2: Impact N-2 Exposure of persons to or generation of excessive ground-borne vibration or ground-borne noise levels. Construction-related activities associated with the proposed project would intermittently generate groundborne vibration on and adjacent to the site. This may affect existing off-site receptors near the project site and proposed on-site residences, but would not create vibrations that could cause structural damage to adjacent structures within 100 feet of the project site. Impacts would be Class III, less than significant. As discussed under Impact N-1, the construction phase of the project would be temporary, estimated to last approximately 18 months. Project construction would not involve pile driving, blasting, or similar types of construction to create vibrations could cause structural damage to buildings. Project excavation and filling, the main heavy construction activities with this project, do not typically result in substantial vibration impacts. Monterey County General Plan Policy S- 7.8 requires all discretionary projects that have the potential to create vibrations that could cause structural damage to submit a pre-construction vibration study prior to approval of a building permit. Any changes to project construction that could result in such vibrations would be subject to Policy S-7.8 and would be administered during the building permit stage, a nondiscretionary action. The primary vibratory source during construction would likely be large bulldozers and loaded trucks. Table identifies various vibration velocity levels for the types of construction equipment that would operate at the project site during construction. As shown, a typical bulldozer or loaded truck generates an approximate vibration level of VdB at a distance of 50 feet

15 Table Vibration Levels for Construction Equipment Approximate Vibration Decibels (VdB) Equipment 50 feet from construction Hoe Ram 78 Large Bulldozer 78 Loaded Trucks 77 Jackhammer 70 Small Bulldozer 48 Source: FTA, Nearby sensitive receptors are located approximately 50 feet from the use of such equipment, therefore the highest vibration velocity from the project would be 78 VdB. At this velocity, vibration levels would not exceed the FTA recommended 80 VdB threshold for infrequent events at residences and buildings where people normally sleep (Table ). Vibration also would not exceed 95 VdB, the vibration level which would damage extremely fragile historic buildings. In addition, in compliance with County General Plan Policy S-7.9, construction equipment would only operate during daytime hours, and thus would not generate vibration during the nighttime, when people are typically sleeping. Impacts would be less than significant. Mitigation Measures. No mitigation is required. Significance After Mitigation. Impacts would be less than significant without mitigation. Threshold 3: Impact N-3 A substantial permanent increase in ambient noise levels in the project vicinity above levels existing without the project. Occupants of proposed on-site and existing off-site residential units would not experience noise level increases exceeding applicable thresholds as a result of project-generated traffic on Highway 1, Carmel Valley Road, Val Verde Drive, Rio Road, or Carmel Rancho Boulevard. Project-generated traffic would have a less than significant impact on exterior and interior noise levels at existing and proposed sensitive receptors on Val Verde Drive. Impacts would be Class III, less than significant. Implementation of the proposed project would result in an increase in the average number of daily vehicle trips along the segments of Highway 1, Carmel Valley Road, Rio Road, Carmel Rancho Boulevard, and Val Verde Drive. The projected total number of net daily trips generated from the project would be 285, as shown in the Val Verde Subdivision Traffic Impact Analysis (Hatch Mott MacDonald, June 2016). The maximum trip count at any individual

16 intersection is 30 trips, which would occur at the Carmel Rancho Boulevard/Rio Road intersection during the PM Peak Hour. This represents a 3% increase in traffic at that intersection, which currently experiences 1,012 trips in the PM peak hour. In general, a doubling of traffic is required to produce a traffic noise level increase of approximately 3 dba. Therefore, the relatively small increase in traffic associated with the project would not be expected to result in a noticeable increase in area traffic noise along any roadway. As shown in Table , ambient noise levels at the project location are below 50 dba Leq. According to the significance thresholds for increases in traffic-related noise provided in Table , an increase in traffic noise that does not exceed 7 dba would be less than significant. Based on the traffic volumes projected for this project, there would be no discernable change in traffic noise resulting from the project, and traffic noise impacts would be less than significant. Similarly, this level of increase would not result in a change to the General Plan noise contours. The project is currently well outside the 60 CNEL County noise contours for all the major roadways modeled nearest to the project site, and would remain outside those noise contours because project-generated traffic would have no effect on those noise contours. This is consistent with General Plan Policy A-7.7, which requires a project-specific noise impact analysis only for projects within a 60 CNEL noise contour or greater, as well as the County s Community Noise Exposure level of 60 CNEL as a Normally Acceptable noise level for residential uses. Therefore, impacts to proposed on-site and existing off-site residential units would be less than significant. Mitigation Measures. No mitigation is required. Significance After Mitigation. Impacts would be less than significant without mitigation. Threshold 3: Impact N-4 A substantial permanent increase in ambient noise levels in the project vicinity above levels existing without the project. The proposed residential uses would be subject to operational noise generated from existing commercial operations west of the site, as well as noise generated from outdoor activities and operations on nearby school playgrounds. However, noise generated by these uses would not exceed applicable standards. The project would also generate additional noise from operation of the proposed residential uses. These noise impacts would not cause the applicable standards to be exceeded for any nearby uses. Impacts would be Class II, less than significant. The proposed project would be located adjacent to professional commercial uses to the west, residences to the north and south, and undeveloped land to the east that is currently in agricultural production. In addition, Carmel Middle School is located approximately 500 feet east of the northeastern corner of the site. Noise generated from agricultural equipment and/or playground noise related to the school would be periodic, and would therefore not be expected to significantly affect the proposed land uses

17 The proposed project would result in development of the site with single-family residences, which are not land uses that would create a substantial permanent increase in ambient noise levels in the area and would be governed by the Monterey County Code Chapter and 040 not allowing the operation of anything producing noise above 85 dba at a distance of 50 feet, and not allowing noise above 45Leq dba or a maximum dba of 65 between the hours of 10:00 p.m. to 7:00 a.m. The proposed project would generate non-mobile operational noise that would be typical of residential uses, including periodic instantaneous sounds such as conversations, music, general vehicular movement, and doors slamming. These noises produced by the project would be similar to the existing noise environment associated with existing surrounding uses. The noise associated with operation of the proposed residential uses would not substantially impact the existing sensitive receptors in the vicinity of the project. Therefore, noise associated with operation of the proposed residential uses would not substantially impact the existing sensitive receptors near the site. Mitigation Measures. No mitigation is required. Significance After Mitigation. Impacts would be less than significant without mitigation. c. Cumulative Impacts. The geographic extent for the analysis of cumulative stationary noise impacts is generally limited to areas within 0.5 mile of the proposed project. This geographic extent is appropriate for the issue of noise because the project s noise impacts are fairly localized and site-specific. Beyond this distance, impulse noise may be briefly audible and steady construction from the proposed project would generally dissipate such that the level of noise would reduce to below the County s maximum noise standards and/or blend in with the background noise level. Development of past, present and reasonably foreseeable future developments within 0.5 mile of the site could cumulatively increase the potential for exposure of people to increased noise levels associated with construction and operation of the project. The project would contribute to these cumulative effects. As stated in Section 3.8 (Cumulative Projects Setting) in Section 3.0, Environmental Setting, this EIR examines cumulative impacts based on a list of projections provided by the, which would result in an increase of approximately 562 housing units, 15,500 square feet of commercial space, and 16 hotel rooms. This cumulative development has the potential to have a substantially adverse effect on noise, increasing noise on local and regional roads. Cumulative impacts to noise as a result of this transition to a more urbanized character would be significant. Given that the proposed project would result in less than significant noise impacts, or mitigated to that level, within this geographic extent, the project s contribution to this cumulative impact would be less than significant. The geographic extent for the analysis of cumulative transportation noise impacts related to noise is limited to the study area described in Section 4.14, Transportation and Circulation. This area is defined as the geographic extent of the cumulative noise impact area because projectgenerated traffic would be limited to this area. Project-generated traffic is minimal in this area and would disperse to a large number of roadways. As such, it would not create noise above any standards. Given that the proposed project would result in less than significant trafficrelated noise impacts within this geographic extent, the project s contribution to this cumulative impact would be less than significant

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