4.11 NOISE INTRODUCTION FUNDAMENTALS OF NOISE

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1 4.11 NOISE INTRODUCTION This section describes the existing ambient noise in the vicinity of the proposed Project and the anticipated noise impacts of the proposed Project to residents and other sensitive receptors. Mitigation measures to reduce the noise impacts from pipeline construction are identified. The noise measurements used in this section are drawn from the Ambient Sound Level Survey conducted by Behrens and Associates, Inc. (March 2013) for the North Garey oil drilling and production project, and peer-reviewed by Veneklasen Associates for the County. (The North Garey project is located near the town of Garey and the proposed Project right-of-way along Foxen Canyon Road; see Figure 3-1.) The Project noise estimates and impact analysis are based on the Foxen Petroleum Pipeline Project-Construction Noise Impact Study Report (Veneklasen Associates, Inc., February 2014), except as otherwise noted. These studies are provided in Appendix 8 of this EIR. The proposed Project consists of construction of two, parallel, underground pipelines running from ERG s Cantin facility northward approximately 2.9 miles, mainly along Foxen Canyon Road, to tie into the existing Phillips 66 Sisquoc Pipeline at the northern edge of Garey. Oil tanks and related equipment would be installed at the Cantin facility. Valves, meters, piping and a valve box would be constructed at the Sisquoc Pipeline tie-in point. Pipeline construction involves trenching operations, installation of pipes, compacting of soil and paving along the pipeline route. Three road bores are proposed FUNDAMENTALS OF NOISE Noise may be defined as unwanted sound. It is often objectionable because it is disturbing or annoying. The objectionable nature of noise can be caused by its pitch or its loudness. Pitch depends on the frequency of the vibrations that produce the sound. Higher pitched signals sound louder to humans than sounds with a lower pitch. Loudness is the amplitude of sound waves combined with the reception characteristics of the ear. Commonly used technical acoustical terms are defined in Table Decibels and Frequency In addition to the concepts of pitch and loudness, several noise measurement scales are used to describe noise. The db is a unit of measurement that indicates the relative amplitude of a sound. Zero on the decibel scale is based on the lowest sound pressure that a healthy, unimpaired human ear can detect. Sound levels in decibels are calculated on a logarithmic basis. An increase of 10 db represents a tenfold increase in acoustic energy, while 20 db is 100 times more intense, 30 db is 1,000 times more intense, etc. There is a relationship between the subjective noisiness or loudness of a sound and its level. Each 10 db increase in sound level is perceived as approximately a doubling of loudness over a wide range of amplitudes. Because decibels are logarithmic units, sound pressure levels are not added arithmetically. When two sounds of equal sound pressure level are added, the result is a sound pressure level that is 3 db higher. For example, if the sound level is 80 db when one backhoe is operating, then it would be 83 db

2 when two backhoes are operating at the same distance from the observer. Doubling the amount of energy would result in a 3 db increase to the sound level. Noise levels do not change much when a quieter noise source is added to relatively louder ambient noise levels. For example, if a 60 db noise source is added to 70 db ambient noise levels, the resulting noise level is 70.4 db. Frequency relates to the number of pressure oscillations per second, or Hertz (Hz). The range of sound frequencies that can be heard by healthy human ears is from about 20 Hz at the lowfrequency end to 20,000 Hz (20 kilohertz [khz]) at the high-frequency end. Table Definitions of Acoustical Terms Decibel (db) Term Sound Pressure Level Frequency (Hertz [Hz]) A-Weighted Sound Level (dba) Equivalent Noise Level (L eq ) Community Noise Equivalent Level (CNEL) Day/Night Noise Level (L dn ) Minimum noise level (L min ) Maximum sound level (L max ) Definition A unit describing the amplitude of sound equal to 20 times the logarithm to the base 10 of the ratio of the pressure of the sound measured to the reference pressure. The reference pressure for air is 20 micropascals. Sound pressure is the sound force per unit area, usually expressed in micropascals (or micronewtons per square meter), where 1 pascal is the pressure resulting from a force of 1 newton exerted over an area of 1 square meter. The sound pressure level is expressed in decibels as 20 times the logarithm to the base 10 of the ratio between the pressures exerted by the sound to a reference sound pressure (e.g., 20 micropascals in air). Sound pressure level is the quantity that is directly measured by a sound level meter. The number of complete pressure fluctuations per second above and below atmospheric pressure. Normal human hearing is between 20 and 20,000 Hz. Infrasonic sounds are below 20 Hz, and ultrasonic sounds are above 20,000 Hz. The sound pressure level in decibels as measured on a sound level meter using the A-weighting filter network. The A-weighting filter deemphasizes the very low- and very high-frequency components of the sound in a manner similar to the frequency response of the human ear and correlates well with subjective reactions to noise. The average A-weighted noise level during the measurement period. An hourly measurement period for L eq is used in this report. The average A-weighted noise level during a 24-hour day obtained after the addition of 5 db to sound levels in the evening from 7 p.m. to 10 p.m. and after the addition of 10 db to sound levels in the night between 10 p.m. and 7 a.m. The average A-weighted noise level during a 24-hour day obtained after the addition of 10 db to levels measured in the night between 10 p.m. and 7 a.m. The minimum noise level measured during the measurement period The maximum noise level measured during the measurement period. L 1, L 10, L 50, L 90 The A-weighted noise levels that are exceeded 1%, 10%, 50%, and 90% of the time during the measurement period.

3 Term Ambient Noise Level Intrusive Definition The composite of noise from all sources near and far. The normal or existing level of environmental noise at a given location. Noise that intrudes over and above the existing ambient noise at a given location. The relative intrusiveness of a sound depends upon its amplitude, duration, frequency, time of occurrence, presence of pure tones, impulsiveness, and informational content, as well as the prevailing ambient noise level. There are several metrics for characterizing sound. The most common is the dba. This scale gives greater weight to the frequencies of sound to which the human ear is most sensitive. Studies have shown that the dba is closely correlated with annoyance to traffic noise. Other frequency weighting networks, such as C-weighting, or dbc, have been developed to describe noise levels for specific types of noise (e.g., explosives). Table shows typical A-weighted noise levels that occur in human environments. Table Typical Noise Levels in the Environment Noise Level dba 120 Extremes Jet aircraft at 500 feet Home Appliances Speech at 3 Feet Motor Vehicles at 50 Feet General Type of Community Environment Chain saw Power lawnmower Diesel truck (not muffled) Shop tools Shout Diesel truck (muffled) Blender Loud voice Automobile at 70 mph Dishwasher Normal voice Automobile at 40 mph Air-conditioner Refrigerator Normal voice (back to listener) Automobile at 20 mph Major metropolis Urban (daytime) Suburban (daytime) Rural (daytime) 50 Threshold of hearing Source: Harris Miller Miller & Hanson, Inc

4 Noise Descriptors Because sound levels can vary markedly over a short period of time, a method for describing either the average character of the sound or the statistical behavior of the variations is utilized. Most commonly, environmental sounds are described in terms of an average level that has the same acoustical energy as the summation of all the time-varying events. This energy-equivalent sound/noise descriptor is called L eq. A common averaging period is hourly, but L eq can describe any series of noise events of arbitrary duration. The noise measurements used in this EIR to estimate ambient noise in the Project vicinity are hourly averages. The scientific instrument used to measure noise is the sound level meter, which can accurately measure environmental noise levels to within approximately plus or minus 1 dba. Two metrics are commonly used to describe the 24-hour average: Day/Night Noise Level (L dn ) and Community Noise Equivalent Level (CNEL). Both metrics include penalties for noise during the nighttime hours (10 p.m. to 7 a.m.). CNEL also penalizes noise during the evening hours (7 p.m. to 10 p.m.). CNEL and L dn are normally within 1 dba of each other and are used interchangeably in this section Human Response to Noise Noise-sensitive receptors are generally defined as locations where people reside or where the presence of unwanted sound may adversely affect the use of the land. Noise-sensitive receptors typically include residences, hospitals, schools, guest lodging, libraries, and certain types of passive recreational uses. Noise-sensitive receptors located in the Project vicinity include existing residences and the Benjamin Foxen Elementary School. Studies have shown that under controlled conditions in an acoustics laboratory, a healthy human ear is able to discern changes in sound levels of 1 dba. In the normal environment, changes in noise level of 3 dba are considered just noticeable to most people. A change of 5 dba is readily perceptible, and a change of 10 dba is perceived as being twice as loud. Noise and Health A number of studies have linked increases in noise with health effects, including hearing impairment, sleep disturbance, cardiovascular effects, psychophysiological effects, and potential impacts on fetal development (Babisch 2005). Potential health effects appear to be caused by both short- and long-term exposure to very loud noises and long-term exposure to lower levels of sound. Acute sounds (i.e., L AF 1 greater than 120 db) can cause mechanical damage to hair cells of the cochlea (the auditory portion of the inner ear) and hearing impairment (Babisch 2005). An L AF greater than 120 db is equivalent to a rock concert or an airplane flying overhead at 984 feet. The World Health Organization and the EPA consider an L eq equal to 70 dba to be a safe daily average noise level for the ear. However, even this ear-safe level can cause disturbance to sleep and concentration and may be linked to chronic health impacts such as hypertension and heart disease (Babisch 2006). A number of studies have looked at the potential health effects of chronic lower noise levels, such as traffic, especially as these noise levels affect children. In a study of school children in 1 L AF = sound level with A frequency weighting and fast-time weighting

5 Germany, blood pressure was 10 mmhg 2 higher in a group of students exposed to road traffic noise from high-traffic transit routes (Babisch 2006). A study by Kwanda (2004) showed that exposure to airplane noise was found to be associated with decreased fetal body weight in pregnant women. Noise Annoyance People s response to environmental noise is subjective and varies considerably from individual to individual. Noise in the community has often been cited as a health problem, not in terms of actual physiological damage, such as hearing impairment, but in terms of inhibiting general wellbeing and contributing to stress and annoyance. When community noise interferes with human activities or contributes to stress, public annoyance with the noise source increases. Annoyance may occur at noise levels well below levels known to cause direct physiological harm. Unwanted noise interferes with human activities by distracting attention and by making activities more difficult to perform, especially when concentration is needed. Interference from noise can even make some activities (such as communication or sleep) virtually impossible. However, except in the case of interference with verbal communication, the degree of interference is difficult to quantify or to relate to the level of noise exposure. [U.S. EPA 1978] The degree of interference and annoyance depends on noise volume, duration and frequency of occurrence, time of year, time of day or night, accustomed ambient noise levels, previous experiences of intrusive noise, attitude toward the noise source, and noise characteristics. [U.S. EPA 1978] Noises that can be particularly annoying include: pure tones (e.g., truck back-up beepers), low-frequency noise (e.g., rumbling of heavy equipment), and impulsive noise (e.g., helicopters, pile drivers) Sound Propagation When sound propagates over a distance, it changes in both level and frequency content. The manner in which noise is reduced with distance depends on the factors discussed below. Geometric spreading: In the absence of obstructions, sound from a single source (i.e., a point source) radiates uniformly outward as it travels away from the source in a spherical pattern. The sound level attenuates (or drops off) at a rate of 6 dba for each doubling of distance. Highway noise is not a single stationary point source of sound. The movement of vehicles that are spaced closely along a busy highway makes the source of the sound appear to emanate from a line (i.e., a line source) rather than from a point. This results in cylindrical spreading rather than the spherical spreading from a point source. The drop-off in sound level from a line source is 3 dba per doubling of distance. A highway with lighter traffic that cannot be modeled as a continuous line source, the drop-off in sound level is intermediate and a rate of 4.5 dba for each doubling of distance may be a reasonable approximation. Ground absorption: Usually the noise path between the source and the observer is very close to the ground. Noise attenuation from ground absorption and reflective wave canceling adds to the attenuation caused by geometric spreading. Traditionally, the excess attenuation has also been expressed in terms of attenuation per doubling of distance. This approximation is done for 2 mmhg = millimeter of mercury

6 simplification only; for distances of less than 200 feet, prediction results based on this scheme are sufficiently accurate. For acoustically hard sites (i.e., sites with a reflective surface, such as a parking area or a smooth body of water, between the source and the receptor), no excess ground attenuation is assumed. For acoustically absorptive or soft sites (i.e., sites with an absorptive ground surface, such as soft dirt, grass, or scattered bushes and trees), an excess ground attenuation value of 1.5 dba per doubling of distance is normally assumed. When added to the geometric spreading, the excess ground attenuation results in an overall drop-off rate of 4.5 dba per doubling of distance for a line source and 7.5 dba per doubling of distance for a point source. Atmospheric effects: Research by Caltrans and others has shown that atmospheric conditions can have a major effect on noise levels. Wind has been shown to be the single most important meteorological factor within approximately 500 feet, whereas vertical air temperature gradients are more important over longer distances. Other factors, such as air temperature, humidity, and turbulence, also have major effects. Receptors located downwind from a source can be exposed to increased noise levels relative to calm conditions, whereas locations upwind can have lower noise levels. Increased sound levels can also occur because of temperature inversion conditions (i.e., increasing temperature with elevation). Shielding by natural or human-made features: A large object or barrier in the path between a noise source and a receptor can substantially attenuate noise levels at the receptor. The amount of attenuation provided by this shielding depends on the size of the object, proximity to the noise source and receptor, surface weight, solidity, and the frequency content of the noise source. Natural terrain features (such as hills and dense woods) and human-made features (such as buildings and walls) can substantially reduce noise levels. Walls are often constructed between a source and a receptor specifically to reduce noise. A barrier that breaks the line of sight between a source and a receptor will typically result in at least 5 db of noise reduction. A higher barrier may provide as much as 20 db of noise reduction. Temporary noise control barriers can be used to mitigate objectionable noise from construction, drilling, and other short-term, noise-generating activities ENVIRONMENTAL SETTING The proposed Project is located within and south of the community of Garey in a rural, sparsely populated area of the County, surrounded by agricultural land and oilfields. The Sisquoc River lies approximately one half mile to the east of Garey, and visible a few miles beyond it are the San Rafael Mountains and Los Padres National Forest. According to the 2010 Census, Garey had a population of 68 people. The major roads running through the community are Foxen Canyon Road, which runs north-south bisecting the residential areas, and Santa Maria Mesa Road, which runs east-west, bounding the North Garey residential area on the north side. The Garey Store on Foxen Canyon Road is the only retail services establishment in the immediate vicinity. The Project includes a tie-in to the Sisquoc Pipeline at the northern edge of Garey, a 2.9 mile pipeline running southward through the community and along Foxen Canyon Road, and the Cantin Tank Battery. The location of these Project components in relation to noise-sensitive receptors is discussed in Section Affected Noise-Sensitive Receptors

7 Existing Ambient Noise Sources of noise evident in the Project area are vehicular traffic, agricultural operations, oilfield operations, activities of residents, and potentially include construction and maintenance projects. Foxen Canyon Road and Santa Maria Road are secondary roads that carry substantial traffic including trucks through Garey. East Betteravia Road is several miles away, but likely contributes to background noise in the area. (See Section 4.14 Transportation and Table ) The County employed acoustical consultant Veneklasen Associates, Inc. (VA) to evaluate baseline ambient noise levels in the Project vicinity and assess noise impacts of the Project on residences and other sensitive receptors. The noise estimates and impact analysis in this EIR are based on the Foxen Petroleum Pipeline Project-Construction Noise Impact Study Report (VA, February 2014), except as otherwise noted. The report is included in Appendix 8 of this EIR. To evaluate existing ambient noise levels, VA utilized existing data from long-term noise measurements of ambient noise. VA verified these data with new short-term noise measurements in September The existing, long-term data was drawn from the noise study conducted by Behrens and Associates, Inc. (March 2013) for the nearby North Garey Project (Appendix 8). The Behrens study recorded noise levels continuously for five days at five locations, three of which are adjacent to the proposed pipeline route along Foxen Canyon Road. VA used the noise data from these three locations to estimate the average ambient daytime noise level (L eq ) and the day-night average noise level (CNEL). The average hourly daytime noise levels derived from Behrens data and short-term noise levels measured by VA are in close agreement. They are summarized in Table Based on these results, VA concluded that the measured noise levels in Behrens long-term data are controlled by vehicular traffic and that the average noise levels calculated from this data can be used for estimating the ambient noise levels at receptor locations at varying distances from the roadway. Table Results of Ambient Noise Surveys Survey Locations (Note 1) I II III Long Term Noise Measurements (Note 2) Notes: 1. Location I was in Stewart Street at approximately 50 feet away from Foxen Canyon Road. Long term measurements at locations II and III were performed at about 12 feet away from Foxen Canyon Road. 2. The L eq data are included in the report dated March 8, 2013 titled Ambient Sound Level Survey Report prepared by Behrens and Associates Inc. These L eq values are the energy averages of measured noise levels for the hours of 8:00 am to 5:00 pm. The CNEL values were calculated using averages of hourly noise levels over Short Term Measurements Measures at 50 (Note 3) L eq (daytime average) CNEL L eq (daytime) 63 dba (50 E. on Stewart St.) 66 dba (12 from road) 66 dba (12 from road) 65.5 (50 E. on Stewart St.) dba (50 E. on Stewart St.) 64 dba 68 dba (estimated at 12 ) 64 dba 68 dba (estimated at12 )

8 three days, as shown in the report. The lower level at location I is due to the greater distance from Foxen Canyon Road. 3. These short-term hourly L eq data were collected by VA at 50 feet away from the Foxen Canyon Road. The measurements at location I in Behrens report and VA s measurements are in agreement as they were performed at approximately the same distance from the Foxen Canyon Road. The estimated noise levels using VA s short term data at locations II and III are also in agreement with the data in Ambient Sound Level Survey Report. These estimates are based on attenuation factor of 4.5 decibels for each doubling of distance from the source Affected Noise-Sensitive Receptors The proposed tie-in of the Foxen Pipeline into the Sisquoc Pipeline (at the northern terminus of the Foxen Pipeline) would be located in an agricultural field at the northern edge of Garey. The site is 50 feet north of Santa Maria Mesa Road and approximately 140 feet from the nearest residential property, which is across Santa Maria Mesa Road. A proposed construction lay-down area is approximately 95 feet from the same property. The proposed pipeline route runs through North Garey: along Andrew Avenue, Stewart Street and Foxen Canyon Road. Portions of the pipeline would be located very near occupied residences, in some cases as close as feet from their front doors. South of the Garey residences, the proposed pipeline alignment follows Foxen Canyon Road for over 1½ miles, bounded by oilfields to the southwest and agricultural fields and greenhouses to the east. There are few residences along this stretch. Most of the proposed pipeline route would be near enough to noise-sensitive receptors potentially to cause construction noise impacts. However, a stretch along Foxen Canyon Road between noise survey Location III and the Cantin Facility entrance road is more than 1,600 feet from noise-sensitive receptors, which is sufficient distance to reduce construction noise to a less than significant level. (See Section , below.) At its southern end, the pipeline route loops to the west, away from Foxen Canyon Road and toward the Cantin facility. The closest residence to the pipeline in this area is approximately 400 feet to the east of the pipeline route. The Benjamin Foxen Elementary School grounds are approximately and 700 feet east of the pipeline route; and the nearest school building is approximately 1,200 feet east of the pipeline route. The Cantin Tank Battery is on a hill, approximately 150 feet higher in elevation than the school and residence. The nearest residence is approximately 2,700 feet east of the tank battery, and the Benjamin Foxen Elementary School grounds are located approximately and 2,900 feet east of the tank battery. The locations of affected sensitive receptors and their distances from the pipeline alignment are shown in a series of figures (photomaps) in the VA report (Appendix 8). The figures were originally prepared by SCS Tracer (2012) and were submitted with the Project application. For the purpose of noise analysis, VA modified the figures to classify and label the sensitive receptors in three categories, according to their distances from the proposed pipeline alignment. The categories are A (15-40 feet away from the pipeline alignment), B (62-96 feet away), C ( feet away), and [not classified] (more than 150 feet away). The modified figures also indicate the noise monitoring locations used in Behrens ambient noise study. A list of the

9 affected receptors is included in Table The noise impacts at receptors with direct line-ofsight to the pipeline alignment would be more severe than at receptors that are shielded by intervening structures. Table Affected Noise-Sensitive Receptors APN Receptor Street Distance to Pipeline (ft.) Direction to Pipeline Distance Category Andrew Ave. 62 W B Andrew Ave. 38 E A Stewart Rd. 84 S B Stewart Rd. 151 S C Stewart Rd. 212 S Stewart Rd. 94 S B Stewart Rd. 168 S Stewart Rd. 80 S B Stewart Rd. 273 S Stewart Rd. 93 S B Foxen Canyon Rd. 96 E B Foxen Canyon Rd. 95 E B Foxen Canyon Rd. 130 E C Foxen Canyon Rd. 88 E B Foxen Canyon Rd. 89 E B Foxen Canyon Rd. 188 E C Foxen Canyon Rd. 77 E B Foxen Canyon Rd. 132 E C Foxen Canyon Rd. 215 E Foxen Canyon Rd. 325 E Foxen Canyon Rd. 81 E B Foxen Canyon Rd. 214 E Foxen Canyon Rd. 24 W A Foxen Canyon Rd. 24 W A Foxen Canyon Rd. 15 W A Foxen Canyon Rd. 92 W B Foxen Canyon Rd. 180 E Foxen Canyon Rd. 232 E Foxen Canyon Rd. 279 E Foxen Canyon Rd. 123 E C Foxen Canyon Rd. 174 E -- 3 The figures show distances to a business, an abandoned adobe hut, and several agricultural structures. These uses are not considered noise-sensitive receptors under the County Comprehensive Plan Noise Element or County Noise Thresholds. They are included in the figures and in Table , but not treated as sensitive receptors in the EIR analysis

10 APN Receptor Street 4.11 NOISE Distance to Pipeline (ft.) Direction to Pipeline Distance Category Foxen Canyon Rd. 221 E Foxen Canyon Rd. 261 E Foxen Canyon Rd. 12 W A Foxen Canyon Rd. 33 W A Foxen Canyon Rd. 40 W A Foxen Canyon Rd. 24 W A Foxen Canyon Rd. 27 W A Foxen Canyon Rd. 274 W Foxen Canyon Rd. 211 W Foxen Canyon Rd. 322 W Foxen Canyon Rd. 471 W Foxen Canyon Rd. 40 W A Foxen Canyon Rd. 109 W C Foxen Canyon Rd. 128 W C Foxen Canyon Rd. 67 W B Foxen Canyon Rd. 278 W Foxen Canyon Rd. 401 W Foxen Canyon Rd. 111 W C Foxen Canyon Rd. 544 W Foxen Canyon Rd. 113 W C Foxen Canyon Rd. 67 W B Foxen Canyon Rd. 315 W Foxen Canyon Rd. 74 E B Foxen Canyon Rd. 213 E Foxen Canyon Rd. 102 E C Foxen Canyon Rd. 44 W A Foxen Canyon Rd. 405 W Foxen Canyon Rd. 92 W B Foxen Canyon Rd. 218 W Foxen Canyon Rd. 375 W Foxen Canyon Rd. 88 W B Foxen Canyon Rd. 357 W Foxen Canyon Rd. 257 SE Foxen Canyon Rd. 238 SE Foxen Canyon Rd. 357 SE Foxen Canyon Rd. 436 SE Foxen Canyon Rd. 629 SE Foxen Canyon Rd. 293 SE Foxen Canyon Rd. 1,280 SE Foxen Canyon Rd. 1,223 SE Foxen Canyon Rd. 1,241 SE --

11 APN Receptor Street Distance to Pipeline (ft.) Direction to Pipeline 4.11 NOISE Distance Category Foxen Canyon Rd. 1,299 SE (1) 76 Santa Maria Mesa Rd. 70 NE -- Notes: indicates commercial or agricultural establishment indicates school 1. This residence was omitted in the SCS Tracer figures and the VA report. However, the property (outside living area) is located approximately 140 feet from the Sisquoc Pipeline tie-in point, 95 feet from a proposed construction staging area, and the house is approximately 70 feet from a proposed under-road boring location. 2. APN was recently split into two parcels: and The existing ambient noise levels in the project vicinity, as estimated in the Veneklasen report (Appendix 8), are summarized in Table The noise levels are expressed in L eq and CNEL metrics for the three distance categories. Table Noise Receptor Categories and Estimated Ambient Noise Levels Noise Receptor Category and Distance to Pipeline A Feet B Feet C Feet Noise Levels L eq dba CNEL L eq dba CNEL L eq dba CNEL Notes: 1. The average of the measured L eq and CNEL levels for the three locations shown in Table were used for estimating the average ambient noise levels for sensitive receptors at varying distances from the roadway. 2. The ambient noise levels are primarily controlled by the roadway traffic. Since the traffic is not a steady flow, a 4.5 decibel attenuation factor was used for each doubling of distance from the pipeline location along the road shoulder. (This factor is intermediate between a point-source and line-source spreading model.) COUNTY ENVIRONMENTAL THRESHOLDS The County s Environmental Thresholds and Guidelines Manual (October 2008) provides the following thresholds of significance for noise: (a) A proposed development that would generate noise levels in excess of 65 db(a) CNEL and could affect sensitive receptors would generally be presumed to have a significant impact. (b) Outdoor living areas of noise sensitive uses that are subject to noise levels in excess of 65 db(a) CNEL would generally be presumed to be significantly impacted by ambient noise. A significant impact would also generally occur where interior noise levels cannot be reduced to 45 db(a) CNEL or less. (c) A project will generally have a significant effect on the environment if it will increase substantially the ambient noise levels for noise-sensitive receptors adjoining areas. Per item (a) above, this may generally be presumed when ambient noise levels affecting sensitive receptors are increased to 65 db(a) CNEL or more. However, a significant effect may also

12 occur when ambient noise levels affecting sensitive receptors increase substantially but remain less than 65 db(a) CNEL, as determined on a case-by-case level. (d) Noise from grading and construction activity proposed within 1,600 feet of sensitive receptors, including schools, residential development, commercial lodging facilities, hospitals or care facilities, would generally result in a potentially significant impact. According to EPA average construction noise is 95 db(a) at a 50 feet distance from the source. A 6-dB drop occurs with a doubling of the distance from the source. Therefore, locations within 1,600 feet of the construction site would be affected by noise levels over 65 db(a). To mitigate this impact, construction within 1,600 feet of sensitive receptors shall be limited to weekdays between the hours of 8 a.m. to 5 p.m. only. Noise attenuation barriers and muffling of grading equipment may also be required. Construction equipment generating noise levels above 95 db(a) may require additional mitigation. Noise-sensitive land uses (i.e., sensitive receptors) include: residential dwellings; transient lodging; hospitals and other long-term care facilities; public or private educational facilities; libraries, churches; and places of public assembly. Thresholds (a) through (c) are generally applied to post-construction noise, whereas Threshold (d) specifically applies to construction noise. Where temporary construction activities would substantially increase the ambient noise levels for noise-sensitive receptors in adjoining areas, Threshold (c) may also be appropriately applied. This is consistent with the California Environmental Quality Act Guidelines (2012, Appendix G, Section XII(d)) which indicates that A substantial temporary or periodic increase in ambient noise levels in the project vicinity above levels existing without the project, is potentially significant. Limiting exterior noise exposure for these land uses to a level no greater than 65 db(a) CNEL is meant to ensure that interior noise levels are at or below 45 db(a) CNEL. This interior noise criterion is mandated by the State for multiple-family residential development, hospitals and lodging facilities. The County of Santa Barbara also applies the 45 db(a) CNEL interior criterion for all new residential housing types, not simply multi-family residences. This criterion is applicable for design of new residences. Only the exterior 65 db(a) CNEL threshold is applicable to projects that have potential impacts to existing residences and other sensitive receptors REGULATORY SETTING Development Standards Regarding Noise Section B of the County s Land Use and Development Code provides development standards for the location and operation of oil and gas pipelines in the County and includes the following standards regarding noise. The following standard is required: B.1.b: Delivery hours. Except in an emergency, materials, equipment, tools, or pipes shall not be delivered to or removed from a pipeline construction site through streets within a residential zone between the hours of 9 p.m. and 7 a.m. of the next day

13 The following standard may be required as deemed necessary by the County decision-maker: 4.11 NOISE B.2.d: Noise. Proposed facilities shall be designed and housed so that the noise generated by the facilities as measured at the property boundaries shall be equal to or below the existing noise level of the surrounding area except under temporary testing or emergency situations. Measures to reduce adverse impacts (e.g., due to noise, vibration) to the maximum extent feasible shall be used for facilities located adjacent to noise sensitive locations as identified in the Comprehensive Plan IMPACT ASSESSMENT Post-Construction Operational Noise Impacts The proposed Project includes the installation of three 300-horsepower pumps at the Cantin Tank Battery to maintain proper pressures within the pipeline to transport the crude oil. The plans also include several small pumps and an air compressor. All pumps would be electrically powered. Pipeline operation would not require use of internal combustion engines or other equipment with potential to generate high noise levels. Operational noise at the eastern the property line of the Cantin facility, located approximately 1,300 feet from the pumps, would be dba, 4 and likely even lower due to attenuation by the intervening soft ground. The nearest noise-sensitive receptor is a residence located 2,640 feet (approximately one half mile) east of the pumping location, and at that distance operational noise would be further reduced to dba or lower. These noise levels are comparable to the quietest nighttime hourly ambient noise levels measured by Behrens (Appendix 8). Because Project operational noise at the nearest sensitive receptor would be less than 65 dba and would not substantially increase ambient noise levels, operational noise would not exceed County Noise Thresholds (a) and (c). The anticipated low noise levels would result in no impacts to noise-sensitive receptors. Equipment at the Sisquoc Pipeline tie-in location comprises piping, valves, meters, and a pigreceiver. The equipment would not generate noise or cause noise impacts to the nearby residences. The 2.9-mile buried pipeline itself would not generate noise or cause noise impacts Construction Noise Impacts Short-term construction activity would include use of heavy equipment such as bulldozers, backhoes, boring rigs, etc. Pipeline construction activity would occur within close proximity (as near as feet) of residences along Santa Maria Mesa Road, Andrew Avenue, Stewart Street, and Foxen Canyon Road. Construction activity at the Sisquoc Pipeline tie-in location would be as near as 190 feet of a residence, and a proposed lay-down area would be 110 feet from that same residence. Construction at the Cantin Tank Battery location would occur approximately one half mile from the nearest sensitive receptors. Construction of the proposed pipeline system is expected to take approximately 90 days to complete. Construction of the Cantin Tank Battery and Sisquoc Pipeline tie-in would take an 4 Pers. Com., Hooshang Khosrovani, Veneklasen Associates, 2/11/2014, telephone call with John Day, P&D staff

14 additional 60 days. As proposed by the Applicant, this schedule assumes construction would occur from 7:00 am to 7:00 pm daily and would require about days at each location near noise sensitive receptors Construction Equipment The equipment proposed to be be used in construction of the Project and the corresponding noise emission data are included in Table This equipment is the primary source of noise with potential to impact the noise sensitive receptors during the construction period. Generally not all of this equipment would be operating simultaneously during construction. The utilization factor (i.e. the percentage of time when a particular piece of equipment would be operating) varies with the type of construction, schedules and other project-specific conditions. Typical utilization factors for various types of equipment are included in FHWA Construction Noise Handbook. An equipment utilization factor of 40 percent is assumed for this project. Table Construction Equipment Construction Equipment 1 Cantin Facility Noise Level 2 (L eq dba at 50 feet) Backhoe 74 Steel Drum Roll 76 Crane 77 Water Truck 71 Delivery Truck and Trailer 71 Pick-Up Trucks (3) 66 Construction Equipment 1 Underground Pipelines Noise Level 2 (L eq dba at 50 feet) Crane 77 Water Truck 71 Delivery Truck and Trailer 71 Pick-Up Trucks (3) 66 Welding Machines (3) 70 Compactor 79 Excavator 77 A-Frame 76 Pavement Saw 76 Road Boring Machine 76 Dump Truck 75 Backhoe 74 Steel Drum Roll

15 Construction Equipment 1 Sisquoc Pipeline Tie-in Noise Level 2 (L eq dba at 50 feet) Backhoe 74 Crane 77 Dump Truck 75 Welding Machine 70 Pick-Up Trucks (2) 66 Notes: 1. Equipment lists are from Project application, C4. Emissions Calculations (p.8) and a letter from Tracer Environmental (8/15/13) RE: Noise Analysis. 2. Source: Federal Highway Administration (FHWA) Roadway Construction Noise Model, Version Pipeline Construction Noise Impacts Impact Number Impact Description Project Phase Impact Class Noise-1 Pipeline construction noise for portions of the pipeline near residences would result in temporary exceedances of County noise thresholds and disturbance to residents. Construction II Pipeline construction noise estimates are presented in Tables and (See VA, Tables 5 and 6; Appendix 8.) Table is expressed in dba (L eq ), while Table is in CNEL. Both tables show the range of noise levels estimated for the minimum and maximum distance from the pipeline route to sensitive receptors in each of the 3 distance categories. For example, in Table , the estimated total noise (i.e., ambient + construction noise) at distances of 15 to 40 feet (Category A) would range from 91 to 83 dba (L eq ). Table shows that pipeline construction noise would far exceed existing ambient noise at residences over the range of distances analyzed, and a result, average hourly total noise levels would be strongly dominated by construction noise. Exceedances over the existing ambient noise levels would range from 23 to 26 dba (L eq ). The 65 dba criterion set forth in threshold (d) of the County Noise Thresholds (Section ) would be exceeded by 8 to 26 dba (L eq ) for the distances analyzed. These noise impacts from pipeline construction are considered severe, although impacts would be short-term (up to days near any particular residence, based on the Applicant s proposed schedule). Table shows pipeline construction noise, total noise, and noise exceedances in the CNEL metric. CNEL thresholds are not generally applied to short-term construction projects. However, the CNEL estimates provide a more complete picture of the anticipated noise impacts. It is assumed in the CNEL calculations that construction would be limited to the hours of 8 a.m. to 5 p.m., in accordance with Noise Threshold (d). The table shows that noise levels would range from 69 to 86 dba (CNEL) during pipeline construction for the distances analyzed. These levels are

16 substantially higher than the 65 dba (CNEL) threshold for long-term noise impacts (i.e., Noise Threshold (a)). It should be noted that for noise-sensitive receptors located farther away than Category C, pipeline construction noise may be noticeable and could be annoying due to its intermittency, as well its discernible spectral contents that would differ from the accustomed ambient noise environment. However, the estimated increase in noise levels would be 7 dba (L eq ) or less, and would occur during daytime hours only. Additionally, in most cases, those receptors are located to the rear of the Category A-C receptors and would be shielded by the intervening structures; noise levels would also be reduced by temporary noise barriers and other mitigation measures recommended to protect Category A-C receptors. (See the following paragraphs and refer to the figures in Appendix 8 (Sensitive Receptors) for location of sensitive receptors.) Due to the high noise levels estimated at noise-sensitive receptors along the pipeline route, mitigation measures are needed to mitigate otherwise significant noise impacts, consistent with Noise Threshold (d), which states in part: Therefore, locations within 1,600 feet of the construction site would be affected by noise levels over 65 db(a). To mitigate this impact,, construction within 1,600 feet of sensitive receptors shall be limited to weekdays between the hours of 8 a.m. to 5 p.m. only. Noise attenuation barriers and muffling of grading equipment may also be required. This threshold explicitly limits construction noise to 65 dba (L eq ) during evening and nighttime hours (and on weekends and holidays), but it does not place a specific limit on noise levels during weekday hours of 8 a.m. to 5 p.m. Noise reduction measures, including noise attenuation barriers, are left to be determined on a case-by-case basis. Factors to consider include the proximity of noise-sensitive receptors, the type of noise, duration of the impacts, and existing, baseline ambient noise levels (as discussed in Threshold (c) in relation to long-term, day-night average noise levels). An upper limit of 70 dba L eq for short-term construction noise is considered reasonable and appropriate in this case. This project-specific threshold takes into account: 1) that the construction noise and disruption would be as close as feet from residential structures; 2) construction noise would include annoying noise components (such as rumbling of engines, clanging of pipes, and truck back-up beepers); 3) construction near residences would be short-term, however, it would last days, and possibly up to several weeks due to restricted construction hours; and 4) ambient noise levels in the area are far below anticipated construction noise levels. Recommended mitigation measures are listed in Section , Mitigation and Residual Impacts. Mitigation measure Noise-2 would limit construction work to weekdays, 8 a.m. to 5 p.m. (This limitation on construction hours would likely prolong pipeline construction. However, in combination with the recommended noise reduction measures, it would effectively mitigate noise impacts.) Mitigation measure Noise-1would require the Applicant to develop and implement a noise reduction plan that includes equipment noise muffling, installation of adequate portable noise barriers 5 and other noise reduction measures to reduce construction noise impacts to sensitive receptors. This measure is expected to reduce construction noise levels at Category A-C 5 Commercially available portable noise control barrier blankets can achieve noise reductions of decibels or more. See the last page of the VA report in Appendix 8 for a photograph of an example installation

17 receptors to approximately 65 dba or less. With the incorporation of these measures, residual impacts from pipeline construction noise would be less than significant (Class II). Table Pipeline Construction Noise Estimates in Leq Metric Location Category Ambient Noise Levels 8am-5pm dba (hourly) (Note 1) Construction Noise dba (Note 2) Total Noise dba (Note 3) Exceedance Over Ambient Levels Exceedance Over 65 dba A (15 to 40 ) B (62 to 96 ) C (102 to 132 ) Notes: 1. Ambient noise estimates in dba L eq are from Table The Leq levels due to construction were calculated by using the noise level emission data in Table with a utilization factor of 40%. The estimates assume a six decibel reduction for each doubling of distance from the construction sites. 3. Logarithmic sum of ambient noise plus construction noise. Table Pipeline Construction Noise Estimates in CNEL Metric Location Category Ambient Noise (Note 1) Construction Noise (Note 2) Total Noise Exceedance Over 65 dba CNEL A (15 to 40 ) B (62 to 96 ) C (102 to 132 ) Notes: 1. Ambient noise estimates in dba CNEL are from Table The CNEL levels due to construction were calculated by using the noise level emission data shown in Table with a utilization factor of 40% and assuming construction occurs only between the hours of 8:00 am to 5:00 pm. The estimates assume a six decibel reduction for each doubling of distance from the construction sites

18 Construction Noise Impacts at the Sisquoc Pipeline Tie-in 6 Impact Number Impact Description Project Phase Impact Class Noise-2 Construction noise at the Sisquoc Pipeline tie-in would result in temporary exceedances of County noise thresholds and disturbance to residents. Construction II The proposed tie-in point of the Foxen Pipeline into the Sisquoc Pipeline is approximately 50 feet north of Santa Maria Mesa Road. It is approximately 190 feet from the nearest residence (140 feet from the outside living space) on the southwest corner of the intersection of Santa Maria Mesa Road and Andrew Street. A proposed construction lay-down area is approximately 110 feet from the same residence. The tie-in site is approximately 230 feet from a second residence on the southeast corner of the intersection (180 feet to the outside living space). (See Appendix 8 (Sisquoc tie-graphic) for a graphic showing of the proposed tie-in layout.) The nearest two residences are located approximately 50 and 100 feet from Santa Maria Mesa Road, which has a traffic volume comparable to Foxen Canyon Road. It is assumed, for lack of noise measurements at this specific location, that the existing, average, ambient daytime noise levels at these two residences are approximately 56 and 52 db, respectively, consistent with the noise estimates in Table Construction of the tie-in is estimated to take 90 days, as proposed. Duration of activities at the lay-down area is unspecified, but could extend for the proposed project duration of 120 days. However, the construction timelines may be substantially longer than proposed by the Applicant, due to the restriction of construction hours to weekdays, 8 a.m. to 5 p.m., in accordance with County Noise Threshold (d). Therefore, residences located near the tie-in point could be exposed to elevated noise levels for several months. Temporary construction noise estimates for the tie-in location are presented in Table Tie-in construction would increase noise levels by 5-7 dba L eq above 65 dba L eq and by dba L eq above average ambient noise levels at the nearest residences. In addition to the noise due to construction of the tie-in facilities, nearby residences would be exposed to noise from truck traffic entering and exiting the construction site directly across Santa Maria Mesa Road to access the Sisquoc Pipeline tie-in construction site and the lay-down area. Additional noise impacts would result from loading and unloading of materials at the lay-down area, which is immediately adjacent to the roadway. (It should be noted that pipeline construction along Andrew Street and boring under Santa Maria Mesa Road adjacent to the tie-in location are pipeline construction impacts, which are discussed in Section ). The anticipated noise impacts at the tie-in location, while less severe than impacts at various points along the pipeline route, would expose residences to construction noise for a longer 6 This analysis was prepared by P&D staff. The analysis by VA (Appendix 8) was incomplete, due to omission of the nearest residence in the parcel-level maps submitted with the Project application