APPENDIX E NOISE
4 5 d B. c o m, L L C Acoustics Consulting P.O. Box 1406 San Luis Obispo California 93406 D AVID L ORD, P H.D. Principal Consultant tel. 805.704.8046 email: dl@45db.com February 17, 2014 Cate School Sound Level Assessment Project 1436 This report describes sound levels at the north property line of the Cate School, Carpinteria, CA with regard to amplified music and amplified voice operations on site. A series of continuous sound level measurements were made in the athletic field area depicted in the figure on page 2. The amplified voice and music study was conducted on Thursday, February 13, 2014, beginning at 10 am with a property line sound level monitor. Two staff members and the assistant headmaster assisted in two typical equipment setup and operation after 10:30 am. Two amplified speaker systems with recorded music and voice announcements at typical volumes were studied in relation to the north property line. The larger amplified speakers were studied in two locations, above and below a bermed wall. Two sound level meters were used during the study: One stationary sound level meter was continuously running at the north property line from 10:00 am, in the position indicated as A on the site plan. The second sound level meter was handheld and was moved between the amplified sound system locations at B, C and D and the property line, A. Both sound level meters are Larson Davis 820 Type 1 data-logging meters, accurate to within one decibel. The procedure for measurement described in A.S.T.M. E-1014 Standard Guide for Measurement of Outdoor A-Weighted Sound Levels was followed. The sky was mostly clear, the wind speed less than 5 mph, at about 70 degrees F. temperature. Both sound level meters were freshly calibrated, and microphones provided with a three-inch foam wind screen to reduce the influence of wind. The meters were time-synchronized with each other so that sound levels in various locations could be compared synchronously with the sound level at the property line. Although sound levels at the speakers ranged between 80 dba to 90 dba, at no time during the amplified sound study did the simultaneous sound level at the north property line exceed 55 dba (see figure on page three). At 11 am, an additional stationary source of sound was assessed at the north boundary, the water treatment system (W). Sound level at the property line near the water treatment system is a constant average 58 dba (see figure on page three between 10:59 and 11:06 am). An acoustic simulation of sound levels beyond the property line toward the north is shown in the figure on page four. The nearest residential potential receptor is approximately 1,000 feet or more from the proposed amplified music and voice announcement source. Ambient sound level in the neighborhood is around 45 dba. Any sound levels that rise above 45 dba may be audible in the surrounding neighborhood, even if sound level is less than 65 dba at the property line of Cate School. page 1 of 4 45dB.com, LLC tel: 805.704.8046
Conclusion: The use of amplified voice and music systems as demonstrated complies with and does not exceed the County of Santa Barbara noise standard of 65 dba at the property line. Figure 1. Site Plan showing location of speakers and sound level measurements. page 2 of 4 45dB.com, LLC tel: 805.704.8046
Figure 2. Sound Level Measurement results. See text for explanation. page 3 of 4 45dB.com, LLC tel: 805.704.8046
Figure 3. Acoustic simulation of sound level from amplified source to north property line and beyond. Sounds from the amplified source become inaudible as they drop below the ambient Sound level of about 45 dba page 4 of 4 45dB.com, LLC tel: 805.704.8046
Sound Level Assessment for the Proposed Cate School Conditional Use Permit and Updated Master Plan 1970 Lillingston Canyon Road Carpinteria, CA requested by Cate School Carpinteria, CA August 28, 2014 David Lord, PH.D. Acoustics Consulting 45dB.com P.O. Box 1406 San Luis Obispo California 93406 tel. 805.704.8046 email: dl@45db.com
Table of Contents 1.0 Description and Criteria...3 2.0 Regulatory Setting...3 2.1 County of Santa Barbara - Comprehensive Plan Noise Element...3 3.0 Impact Thresholds...5 4.0 Potential Impacts...5 5.0 Discussion and Conclusion....6 6.0 REFERENCES...9 7.0 APPENDIX I: Notes, Definitions...10 8.0 APPENDIX II: Acoustical Modeling Methods...11 List of Figures Figure 1. Site Plan...7 Figure 2. Comprehensive Sound Level Projection...8 Figure 3. Play Activities...9 Cate School Sound Level Assessment page 2 08/28/14
Sound Level Assessment for the Proposed Cate School Conditional Use Permit and Updated Master Plan 1970 Lillingston Canyon Road Carpinteria, CA 1.0 Description and Criteria This is a report on existing and future sound levels at the Cate School in Carpinteria, with regard to the application for a conditional use permit and updated master plan. Sound levels are evaluated with reference to the community noise criteria contained in the County of Santa Barbara General Plan Noise Element and Land Use Compatibility Guidelines, as well as the County of Santa Barbara Environmental Thresholds and Guidelines Manual. With regard to land use, potential noise conflict and noise mitigation measures, the noise level standards contained in the Noise Element of the General Plan of the County of Santa Barbara (rev. 1986) are also considered. The Noise Element sets a limit of Ldn = 65 dba for residential outdoor activity areas (pages 58-59) and a limit of Ldn = 45 dba for interior noise sensitive uses for nearby residential potential sensitive receptors. The terms Ldn and CNEL are used to describe 24-hour average sound levels with penalties for nighttime noise. (see 7.0 APPENDIX I: Notes, Definitions on page 10 for explanation of terms). The site plan of the existing and future Cate School is shown in Figure 1. Site Plan on page 7. 2.0 Regulatory Setting The Cate School proposed project is located in unincorporated Santa Barbara County. The project must comply with the noise policies and standards contained within the County s Comprehensive Plan Noise Element and the County s Noise Ordinance. The following provides an overview of the County of Santa Barbara noise policies, regulations, and standards extracted from these documents and their applicability to the proposed project. 2.1 County of Santa Barbara - Comprehensive Plan Noise Element The County has established land use noise compatibility guidelines for new developments in the Noise Element of the County s Comprehensive Plan (County of Santa Barbara, adopted 1979, revised 1986). These guidelines identify compatible exterior noise levels associated with transportation for various land use types. Hotel, motels, and similar uses are defined as noise sensitive land uses in the Noise Element of the County s Comprehensive Plan. Cate School Sound Level Assessment page 3 08/28/14
The following paragraphs, extracted from the County s policies in the Noise Element are applicable to the proposed Cate School project: In the planning of Land use, 65 dba Day-Night Average Sound Level (Ldn) should be regarded as the maximum exterior noise exposure compatible with noise-sensitive uses unless noise mitigation features are included in project designs. Noise-sensitive uses proposed in areas where the Day-Night Average Sound Level is 65 dba Ldn or more should be designed so that interior noise levels attributable to exterior sources do not exceed 45 dba Ldn when doors and windows are closed. An analysis of the noise insulation effectiveness of proposed construction should be required, showing that the building design and construction specifications are adequate to meet the prescribed interior noise standard. Residential uses proposed in areas where the Day-Night Average Sound Level is 65 dba Ldn or more should be designed so that noise levels in outdoor living spaces will be less than 65 dba Ldn. An analysis of proposed projects should be required, indicating the feasibility of noise barriers, site design, building orientation, etc., to meet the prescribed exterior noise standard. The County of Santa Barbara Noise Ordinance, Chapter 40 (Sec. 40-2 - Noises Prohibited) provides the following regulations with possible relevance to project operations: Sec. 40-2. Noises prohibited. It shall be unlawful within the unincorporated area of the County of Santa Barbara to make, assist in making, permit, continue, create, or cause to be made, any loud and unreasonable noise, music, percussion or other sound which is broadcast outside of any residence or building by means of any amplified musical instrument, drum, or similar device, or by means of any radio, loudspeaker, sound amplifier or phonograph, or by means of or employing any similar device which amplifies and produces, reproduces or broadcasts sound, during any of the following periods of time: The night and following morning of any Sunday, Monday, Tuesday, Wednesday, or Thursday between the hours of 10:00 P.M. of such day and 7:00 A.M. the following morning; or, The morning hours after midnight of any Friday or Saturday, between twelve midnight, following such day, and 7:00 A.M. the following morning. Within such time periods, and for the purposes of this chapter, a loud and unreasonable sound shall include any sound created by means prohibited above which is clearly discernable at a distance of one hundred feet from the property line of the property upon which it is broadcast or which is at any level of sound in excess of sixty decibels at the edge of the property line of the property upon which the sound is broadcast. Cate School Sound Level Assessment page 4 08/28/14
3.0 Impact Thresholds The Cate School site and surrounding area contain noise sensitive land uses or receptors as defined in the County of Santa Barbara Environmental Thresholds and Guidelines Manual. The definition includes residential areas and educational facilities, libraries, churches, and places of public assembly. The following are thresholds of significance for assisting in the determination of significant noise impacts. The thresholds are intended to be used with flexibility, as each project must be viewed in its specific circumstances: (a) A proposed development that would generate noise levels in excess of 65 dba 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 dba 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 dba 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 in adjoining areas. Per item (a), this may be presumed to be the case when ambient noise levels affecting sensitive receptors are increased to 65 dba CNEL or more. However, a significant effect may also occur when ambient noise levels affecting sensitive receptors increase substantially but remain less than 65 dba CNEL, as determined on a case-by-case level. The County Thresholds and Guidelines Manual does not specify a particular sound level increase that might be considered significant under the last of the above thresholds. Typically, an increase of 3 dba is considered just perceptible, and an increase of 5 dba may be considered a significant effect. 4.0 Potential Impacts Sound levels arising from separate on-site operations and activities are organized by the following operational schedule: 1. Weekday arrival and departure of some students and staff who live off-site, generally from 7:00 am 6:00 pm. 2. Outdoor athletic field activities, based on program needs. For this assessment, athletic activities were observed and sound levels were measured at 24 feet distance and simultaneously at the north boundary during football practice. North boundary sound levels during football practice were always below 55 dba average, with an occasional coaching whistle reaching 60 dba for one or two seconds at the boundary. 3. The existing outdoor swimming pool Aquatic Center activities will be based on program needs, generally within the hours from 7:00 am - 8:00 pm. The swimming pool is Cate School Sound Level Assessment page 5 08/28/14
at a lower elevation and 200 feet distant from the north boundary. Existing activities at the swimming pool are not audible at the north boundary. 4. Landscaping and maintenance activities, including small landscape equipment such as hedge trimmers and noise-compliant leaf blowers, as is typical for an institution. Maintenance personnel accessing the waste water treatment plant periodically are typically quiet in their operations, generally between 7 am and 5 pm. 5. Stationary equipment sound level at building and grounds and waste water treatment plant was observed and measured during normal daytime operation, 60 dba at 9 feet distance toward the south. A temporary 6-foot high, 12-feet long sound barrier wall was installed and tested on the north side of the waste water treatment plant, resulting in a sound level at the north property line of less than 50 dba. The waste water treatment plant operates at a reduced noise level during evening and night hours, due to lower demand. Lower nighttime sound levels significantly reduce the CNEL 24 hour level. 6. Heating, ventilation and air conditioning sound levels at existing and future facilities and buildings will not exceed the 65 dba CNEL sound level allowed by County standard at the property line. 6. Amplified sound associated with athletic activities on the playing fields and occasionally at a student dance or outdoor event, will be operated within the limits of the County of Santa Barbara Noise Ordinance, Chapter 14, section 40-2, which prohibits amplified sound during any of the following periods of time: The night and following morning of any Sunday, Monday, Tuesday, Wednesday, or Thursday between the hours of 10:00 P.M. of such day and 7:00 A.M. the following morning; or, The morning hours after midnight of any Friday or Saturday, between twelve midnight, following such day, and 7:00 A.M. the following morning. Amplified sound level greater than 60 db at the property line is prohibited by the Noise Ordinance, and this sound level shall not be exceeded by amplified sound at Cate School. Amplified music and sound levels on the athletic field area were measured and reported on February 17, 2014. At no time during those measurements did the sound level at the north property line exceed 54 dba, and that level was for a short interval, not sustained. 5.0 Discussion and Conclusion. Examination and review of the existing and proposed operational and activity sound levels for the Cate School facility show that sound levels at the boundaries of the site are lower than the limits prescribed by existing county standards. Potential increase in sound level from any source, either stationary or moving equipment, or operational sound is feasibly mitigable to less than a three decibel increase at the property line. By that measure, any increase will be barely perceptible and will therefore have a less-than-significant future impact. Cate School Sound Level Assessment page 6 08/28/14
Figure 1. Site Plan Site Plan of Cate School site, Carpinteria. Cate School Sound Level Assessment page 7 08/28/14
Figure 2. Comprehensive Sound Level Contours Site Plan showing comprehensive sound level contours on the north side of the property (Ldn = dba). Contours are projected for stationary and transportation sources and outdoor activities at the proposed facility. The sound level contours are discussed in 4.0 Potential Impacts on page 5. The proposed sound level contours are affected by topography and existing nearby buildings and activities. Cate School Sound Level Assessment page 8 08/28/14
6.0 REFERENCES 1. American National Standards Institute, Inc. 2004. ANSI 1994 American National Standard Acoustical Terminology. ANSI S.1.-1994, (R2004), New York, NY. 2. American Society for Testing and Materials. 2004. ASTM E 1014-84 (Reapproved 2000) Standard Guide for Measurement of Outdoor A-Weighted Sound Levels. 3. Berglund, Birgitta, World Health Organization. 1999. Guidelines for Community Noise chapter 4, Guideline Values. 4. Bolt, Beranek and Newman. 1973. Fundamentals and Abatement of Highway Traffi c Noise, Report No. PB-222-703. Prepared for Federal Highway Administration. 5. California Department of Finance. 2007. California Strategic Growth Plan. 6. California Department of Transportation (Caltrans). 1982. Caltrans Transportation Laboratory Manual. 7.. 1998. Caltrans Traffi c Noise Analysis Protocol For New Highway Construction and Highway Reconstruction Projects. 8.. 2006. California Transportation Plan 2025, chapter 6. 9. California Resources Agency. 2007. Title 14. California Code of Regulations Chapter 3. Guidelines for Implementation of the California Environmental Quality Act Article 5. Preliminary Review of Projects and Conduct of Initial Study Sections, 15060 to 15065. 10. County of Santa Barbara. County of Santa Barbara General Plan, Noise Element. 11. County of Santa Barbara Environmental Thresholds and Guidelines Manual Published May 1992, revised October 2006. Planning and Development Department 12. Federal Highway Administration. 2006. FHWA Roadway Construction Noise Model User s Guide Final Report. FHWA-HEP-05-054 DOT-VNTSC-FHWA-05-01. 13. Harris, Cyril.M., editor. 1979 Handbook of Noise Control. Cate School Sound Level Assessment page 9 08/28/14
7.0 APPENDIX I: Notes, Definitions TERM Ambient Noise Level Background Noise Level Sound Level, db dba or db(a): Equivalent Sound Level LEQ DEFINITION The composite of noise from all sources near and far. The normal or existing level of environmental noise or sound at a given location. The ambient level is typically defined by the LEQ level. The underlying, ever-present lower level noise that remains in the absence of intrusive or intermittent sounds. Distant sources, such as traffic, typically make up the background. The background level is generally defined by the L90 percentile noise level. Sound Level. Ten times the common logarithm of the ratio of the square of the measured A-weighted sound pressure to the square of the standard reference pressure of 20 micropascals, SLOW time response, in accordance with ANSI S1.4-1971 (R1976) Unit: decibels(db). The A-weighted sound level. The ear does not respond equally to all frequencies, but is less sensitive at low and high frequencies than it is at medium or speech range frequencies. Thus, to obtain a single number representing a sound containing a wide range of frequencies in a manner representative of the ear s response, it is necessary to reduce the effects of the low and high frequencies with respect to the medium frequencies. The resultant sound level is said to be A-weighted, and the units are dba. The A-weighted sound level is also called the noise level. Because sound levels can vary markedly in intensity over a short period of time, some method for describing either the average character of the sound or the statistical behavior of the variations must be utilized. Most commonly, one describes ambient sounds 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 LEQ. In this report, both a 15 minute and an hourly period is used. Day/Night Level (Ldn) Community Noise Equivalent Level CNEL Subjective Loudness Changes. Ldn is the A-weighted equivalent continuous sound level for a 24-hour period with a ten db adjustment added to sound levels that occur during nighttime hours (10 pm to 7 am). Community Noise Equivalent Level, CNEL, is the A-weighted equivalent continuous sound (CNEL) level for a 24-hour period with a ten db adjustment added to sound levels occurring during nighttime hours (10 pm to 7 am) and a five db adjustment added to the sound levels occurring during the evening hours (7 pm to 10 pm). In addition to precision measurement of sound level changes, there is a subjective characteristic which describes how most people respond to sound: A change in sound level of 3 dba is barely perceptible by most listeners. A change in level of 6 dba is clearly perceptible. A change of 10 dba is perceived by most people as being twice (or half) as loud. Time weighting Different, internationally recognized, meter damping characteristics are available on sound level measuring instruments: Slow (S), Fast (F) and Impulse (I). In this community sound level measurement, the Fast (F) response time is used. Cate School Sound Level Assessment page 10 08/28/14
8.0 APPENDIX II: Acoustical Modeling Methods Noise Contour Modeling Noise contours incorporating the measured sound level values were generated using CADNA/A, an acoustical modeling program that incorporates the TNM 2.5 algorithms, and which was developed to predict hourly Leq values for free-flowing traffic conditions. This computer modeling tool, made by Datakustik GmbH, is an internationally accepted acoustical modeling software program, used by many acoustics and noise control professional offices in the U.S. and abroad. The software has been validated by comparison with actual values in many different settings. The program has a high level of reliability and follows methods specified by the International Standards Organization in their ISO 9613-2 standard, Acoustics Attenuation of sound during propagation outdoors, Part 2: General Method of Calculation. The standard states that, this part of ISO 9613 specifies an engineering method for calculating the attenuation of sound during propagation outdoors in order to predict the levels of environmental noise at a distance from a variety of sources. The method predicts the equivalent continuous A-weighted sound pressure level under meteorological conditions favorable to propagation from sources of known sound emissions. These conditions are for downwind propagation under a welldeveloped moderate ground-based temperature inversion, such as commonly occurs at night. The computer modeling software takes into account source sound power levels, surface reflection and absorption, atmospheric absorption, geometric divergence, meteorological conditions, walls, barriers, berms, and terrain variations. The CADNA/A software uses a grid of receivers covering the project site. Cate School Sound Level Assessment page 11 08/28/14
Day Night Site Leq Lmax Leq Lmax 1 78 95.5 101.6 106.7 2a 77.6 96.3 80.9 88.2 2b 73 91.1 3 61.5 74.9 42.2 53.1 4 48.4 60.7 37 50.9 5 42.7 59.3 43.5 66.6