3.3 NOISE Existing Setting Thresholds of Significance

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1 3.3 NOISE Existing Setting Noise is generally defined as unwanted or objectionable sound. Sound levels are expressed as decibels (db). The A-weighted noise level has been developed to correspond with people s subjective judgment of sound levels and is referenced in units of db(a). Sound levels diminish as distance from the source increases. Noise levels from single stationary point sources decrease at a rate of 6 db for every doubling of distance from the source. Noise levels from a line source (e.g. roadway) decrease at a rate of 3 db for every doubling of distance. In general, a 1 db change in ambient noise levels is imperceptible, 3 db is generally noticeable, and 10 db is perceived as nearly half (or twice) as loud. Primary sources of intrusive noise within the rural areas of the County include motor vehicles, agricultural activities, railroads, and airports. Ambient noise levels on most contracted land are expected to be less than 50 db (L dn Day-Night Average Level), which is typical of rural areas, unless the land is adjacent to or in close proximity to roads or railways. Along roadways, such as U.S. Highway 101 and State Highways 1, 246, and 154, noise levels from vehicular traffic can be in excess of 65 db(a) CNEL (Community Noise Equivalent Level) at 50 feet from the nearest travel lane centerline Thresholds of Significance The County of Santa Barbara Environmental Thresholds and Guidelines Manual establishes the following thresholds of significance for noise related impacts, which primarily apply to sensitive receptors. Sensitive receptors include schools, residential development, commercial lodging facilities, hospitals or care facilities: 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 affect on the environment if it will increase substantially the ambient noise levels for noise-sensitive receptors in adjoining areas. Per item a., this may generally be presumed when ambient noise levels affecting sensitive receptors increase substantially but remain less than 65 db(a) CNEL, as determined on a case-by-case basis. 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 guidelines, average construction noise is 95 db(a) at a 50 foot 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). 3.3 Environmental Impact Analysis 3.3-1

2 3.3.3 Project Impacts A. Noise Generation above 65 db or Substantial Increase in Ambient Noise Levels The primary provisions of the amended Uniform Rules that could have noise impacts include residential development, agricultural support facilities, commercial composting facilities, and special events. These issues are discussed below. The noise impacts resulting from other provisions of the amended Uniform Rules are considered to be insignificant and are thus not evaluated in this analysis. Uniform Rules Principal Dwelling and 2-4. Small-Scale Guest Ranches The establishment of additional principal residences on contracted land under the amended Uniform Rules is not expected to result in any adverse impacts in terms of being a significant source of noise. The estimated 233 additional residences beyond what is currently allowed would only occur on the larger contracted premises (minimum 200 acres), with parcels at least 100 acres in size, and would be dispersed throughout the County s contracted land. Development at this level and density would not typically produce sources of noise exceeding the significant impact threshold of 65 db as heard from sensitive noise receptors or result in substantial increases in ambient noise levels. The potential development of 25 small-scale guest ranches on contracted land throughout the rural areas of the County would have similar affects as for principal dwellings. Residential and guest ranch development on contracted land would introduce additional noise-sensitive receptors into the rural areas of the County. This could cause conflicts with surrounding agricultural operations and the noise that is typical of agricultural activities. However, the Right to Farm Ordinance protects agricultural operations from nuisance complaints from neighboring residential use as long as the agricultural activities are properly conducted. This has the effect of a buyer-beware notification for landowners in agricultural areas of the County. In addition, given the large size of parcels that are able to avail themselves of these opportunities, it is likely that proper location and design of these dwellings could result in reduced noise impacts below significant thresholds. For these reasons, noise impacts resulting from residential and guest ranch development under the amended Uniform Rules are considered to be adverse but less than significant. Uniform Rules 2-2. Supportive Agricultural Uses and 2-6. Agricultural Industry Overlay In general, agricultural support facilities are not significant sources of noise in the County s rural areas. Most of these facilities would likely be constructed away from sensitive noise receptors, which in this case would be primarily limited to dispersed residential uses. However, there is the potential for projectspecific conflicts to occur if these facilities are located adjacent to or in close proximity to residential development or other sensitive noise receptors (e.g. schools, churches, etc.), which may be conditionally permitted by existing zoning in rural areas. Additionally, large facilities have the potential to substantially contribute to noise levels coming from traffic along rural roadways if they employ a significant workforce or require significant truck traffic for transporting harvested crops and shipping final product. Noise impacts resulting from these activities are highly site-specific and dependent on a 3.3 Environmental Impact Analysis 3.3-2

3 variety of factors, including the location of the facility relative to sensitive noise receptors, the location of the crops being processed relative to the facility (i.e. whether trucking of the crops to the facility is required), and the number of employees at the facility and where they are traveling to and from. Due to the size and scale of these facilities and the potential concentration of these facilities in particular agricultural regions of the County, noise impacts are considered to be potentially significant. Uniform Rule 2-7. Waste Disposal and Commercial Composting Facilities Commercial composting facilities allowed under the amended Uniform Rules could result in potential noise impacts to noise-sensitive receptors depending on their size and location. Operational equipment and trucking associated with transferring compost materials to and from the site could raise ambient noise levels and impacts for adjacent or nearby residences, or other noise-sensitive receptors. Because the amended Uniform Rules provide no restrictions in terms of the size or location of these facilities, noise impacts are considered to be potentially significant. Uniform Rule Temporary Filming and Special Events Special events do have the potential to raise ambient noise levels or result in short-term impacts to noisesensitive receptors depending on their location relative to residential uses, their size, and the nature of the particular event. Localized impacts could result from special events since the amended Uniform Rules place no restrictions on the size of events, the frequency, or location on the premises of such activities. Therefore, impacts to noise resulting from this provision are considered to be potentially significant. B. Short-term Construction-related Noise All new development allowed under the amended Uniform Rules could result in short-term impacts to noise-sensitive receptors associated with construction and grading activities at the project sites. Noise from grading and construction activity proposed within 1,600 feet of sensitive receptors would generally result in a potentially significant impact. C. Summary of Project Impacts Impact Noise-1: Generation of noise greater than 65 db or substantial increases in ambient noise levels that affect noise-sensitive receptors. Agricultural support facilities, commercial composting facilities, and special events have the potential to impact noise-sensitive receptors by generating noise in excess of 65dB or substantially increasing ambient noise levels depending on their size and location relative to noise-sensitive receptors, and the nature of their operation. Impacts are considered potentially significant. (Addresses Uniform Rules: 2-2 Agricultural Support Facilities, 2-7 Waste Disposal and Commercial Composting Facilities and 2-11 Temporary Filming and Special Events). Impact Noise-2: Short-term noise impacts associated with construction and grading. Greater development opportunities under the amended Uniform Rules would result in potentially significant impacts to noise-sensitive receptors associated with construction and grading activities at project sites. 3.3 Environmental Impact Analysis 3.3-3

4 (Addresses Uniform Rules: 1-4. Principal Dwelling, 2-2 Agricultural Support Facilities, 2-6 Agricultural Industrial Overlay) Mitigation Measures Existing Policies and Development Standards that May Reduce Impacts Existing policies and development standards in the County s Noise Element and adopted community plans, as well as standard conditions applied to permits serve to minimize noise impacts and protect sensitive noise receptors from projects that generate either short or long-term noise beyond established thresholds. In particular, the following requirements address potential noise impacts: Agricultural Industry Overlay (Land Use Element page 174-a): 1.g. The overlay shall not be applied where it would have a significant adverse impact on adjacent residential areas. Conditional Use Permit Findings (Article III, Section & Article II, Section ): 2. That significant environmental impacts are mitigated to the maximum extent feasible. 5. That the project will not be detrimental to the health, safety, comfort, convenience, and general welfare of the neighborhood and will be compatible with the surrounding area. Standard Conditions: Stationary construction equipment that generates noise which exceeds 65 dba at the project boundaries shall be shielded and shall be located away from noise-sensitive receptors. Any short-term noise impacts related to the construction of residences, guest ranches, agricultural support facilities, or other structural development will be required to abide by County standards and conditions that mitigate the impacts of noise on sensitive receptors by limiting construction to specific daytime hours and ensuring that stationary construction equipment which exceeds noise thresholds be shielded and located far enough away from occupied residences or other sensitive receptors so as to minimize impacts. Adherence to these standards would ensure that there would be no significant impacts to surrounding noise-sensitive receptors as a result of short-term noise impacts from construction-related activities. A development plan would be required for the approval of wineries large enough to likely impact noise levels. Findings required for approval of a development plan ensure that a project will be compatible with the surrounding area and any significant impacts are mitigated to the maximum extent feasible. Similar findings are required for approval of a conditional use permit, which would be applied to such uses as guest ranches, commercial composting facilities or larger-scale special events. Furthermore, the Land 3.3 Environmental Impact Analysis 3.3-4

5 Use Element requires that facilities developed under an Agricultural Industry Overlay, which are most likely to have noise impacts due to their scale, must ensure that they do not have a significant adverse impact on adjacent residential areas. In the case of special events on wineries, current LUDC permitting requirements ( ) necessitate the implementation of standard conditions that address noise levels, including controls placed on the use of amplified music and a minimum distance of the event from residential areas. Impacts resulting from such activities would be addressed on a site-specific basis, thus mitigating potential noise impacts from these activities. In the case of non-winery events, an ordinance amendment was recently adopted that requires permits for commercial events, such as weddings, receptions, rodeos and other equestrian activities, the approval of which would require the incorporation of standard conditions that would address potential noise impacts. The County s Right to Farm Ordinance would also address potential noise conflicts between residential uses and agricultural activities by ensuring that new residential development in agricultural areas is aware of the potential nuisances, including noise, which may occur as the natural result of living in or near agricultural areas. Proposed Mitigation Measures No further mitigation measure is deemed necessary beyond policies, standards and regulatory requirements currently in place to adequately mitigate potential noise impacts. These regulatory requirements would be applied on a case by case basis as proposed projects are reviewed during the permit process Residual Impacts Noise impacts associated with activities and uses that may occur on contracted land under the amended Uniform Rules (Impact Noise-1) would be effectively mitigated on a project-specific basis through compliance with existing policies and regulations applied during the permit process Furthermore, the size of rural parcels and the density of residential development will likely facilitate the avoidance of impacts to noise-sensitive receptors from these activities and uses since there is the greater ability for them to be located away from each other. Therefore, impacts would become significant but mitigable (Class II). Short-term noise impacts to noise-sensitive receptors associated with construction and grading at a project site (Impact Noise-2) will become significant but mitigable (Class II) upon implementation of the standard conditions and policy consistency requirements applied to any future development or use requiring a permit. Furthermore, the size of rural parcels and the density of residential development will likely facilitate the avoidance of impacts to noise-sensitive receptors from these activities and uses since there is a greater ability for them to be located away from each other. 3.3 Environmental Impact Analysis 3.3-5