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HomeMy WebLinkAboutCorrespondence - Eilar - 2nd ResponseILAR ASSOCIATES, INC. Acoustical and Environmental Consulting 210 South Juniper Street, Suite 100, Escondido, CA 92025 Phone: 760-738-5570 or 800-439-8205 • Fax: 760-738-5227 www.eilarassociates.com • info@eilarassociates.com January 9, 2018 Job #B60504N5 City of Chula Vista Development Services Department Attention: Caroline Young 276 Fourth Avenue Chula Vista, California 91910 Subject: Second Response to Opposition to Wash -N -Go (DR15-0037; CUP15-0023; PER16-0003) As requested, Eilar Associates, Inc. has reviewed a supplemental letter from Procopio, dated January 4, 2018, regarding the Wash -N -Go car wash project, to be located at 495 Telegraph Canyon Road. The aforementioned letter from Procopio was prepared in response to the previous letter issued by Eilar Associates, Inc., dated October 13, 2017, which responded to initial concerns from certain nearby residents regarding the complete noise study for the project, prepared by HMMH and dated August 7, 2017. The January 4 letter expressed continued concerns regarding the project and the noise study. It remains the opinion of the undersigned that, despite the continued concerns raised in the letter from Procopio, the acoustical report prepared by HMMH adequately addressed the major noise sources associated with the car wash site in comparison to the applicable Municipal Code noise limits. Comments following the review of the January 4 letter are listed below. The letter continues to take issue with the fact that the only noise source evaluated within the report is the car wash dryer system, again mentioning the noise impacts that would result from vacuums, intercoms, and customer noise (idling, radios, loud conversations, car horns). The letter states that, without the inclusion of said sources, the analysis "cannot be used as a basis to determine whether the Project will exceed the municipal code requirements or whether the Project may have an impact on the environment or on the health and welfare of surrounding residents." Eilar Associates disagrees with this statement. As previously detailed within the October 13 letter from Eilar Associates, the noise limits of the Municipal Code are given as hourly noise limits. Although other noise sources may be present, the dryer remains the dominant noise source, and therefore the noise source that drives the hourly noise impacts to adjacent properties, with any other sources expected to be numerically insignificant in comparison. The letter also brings up the question of "whether the Project may have an impact on the environment" and refers to the California Environmental Quality Act (CEQA) in various locations throughout the letter. While the CEQA Environmental Checklist Form contains a list of questions relating to noise impacts to/from project sites for the classification of an impact's significance, the applicable thresholds of significance for a project are set by the Second Response to Opposition to Wash -N -Go (DR15-0037; CUP15-0023; PER16-0003) January 9, 2018 Job #860504N5 Page 2 of 4 Lead Agency. The first question of the checklist asks if the project would result in "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." The noise regulations of the Municipal Code (noise ordinance) have been addressed within the noise study, while the noise limits of the General Plan pertaining to residential properties are more limited to the assessment of transportation noise impacts to sites from surrounding roadways, railways, or airports, and therefore, are not applicable to this site. Furthermore with regards to CEQA, the letter contends that there has not been an evaluation of the increase in permanent, temporary, or periodic ambient noise levels as a result of car wash operation. While this analysis has not been explicitly defined within the noise analysis, the presence of ambient noise measurements along with projected noise impacts from the car wash property make the determination of impacts to the ambient noise level possible through the application of the principles of decibel addition. An informational supplement has been provided as an attachment to this letter presenting the formula for conducting decibel addition. The noise impact at the property line of 484 Hale Street is shown to be 66.0 dBA in the noise analysis, compared to the lowest measured hourly ambient noise level of 66.9 dBA during anticipated business hours. When these impacts are combined, the resulting combined noise impact is 69.5 dBA. The impact of the project on the ambient noise level can be calculated by subtracting the existing ambient noise level from the combined noise level, and therefore, the contribution to the ambient noise level anticipated from this project is 2.6 dBA. While the City of Chula Vista does not have formally adopted significance determination thresholds, a typically accepted threshold of significance is that an increase of 3 dBA or more would be considered a significant impact, as this increase represents a doubling of sound energy. This project's noise contribution would remain below the 3 dBA threshold at the property line, and would also have a significantly lower noise contribution at the residential structures, where the actual noise -sensitive receivers are more likely to be located. In this location, adjacent to residential structures and uphill from the car wash, noise impacts are projected to be 52.5 dBA. When compared to the lowest measured hourly ambient noise level of 66.9 dBA during anticipated business hours, the combined noise impact would be 67.1 dBA—an increase of 0.2 dBA above the ambient noise level. For these reasons, it is the opinion of the undersigned that the impact to existing ambient noise levels would be considered to be less than significant. This statement also refers to the impact of the noise on the "health and welfare" of off-site individuals, seemingly drawing from the City of Chula Vista Municipal Code prerequisites for granting a Conditional Use Permit (CVMC 19.14.080B). Due to the fact that there is no quantitative noise limit tied to this statement, it becomes a subjective noise standard that is therefore unenforceable in terms of noise. The noise limits found within Section 19.68 of the Municipal Code therefore are the only guiding factor in the determination of compliance, and based on the lack of other guidelines, it can be inferred that the City therefore considers compliance with these guidelines to be adequate proof that the general "health and welfare" of individuals would be protected if the established noise standards are met. 2. This letter also contends that "the comparison of the intercom noise and other Unevaluated Noise Sources to the dryer noise is irrelevant; the impact of these noise sources on the environment and surrounding homes is the relevant inquiry." The dryer noise and all other noise sources will exist simultaneously, meaning that they all impact the hourly noise level; however, the degree to which they impact the hourly noise level is a highly relevant factor. Both HMMH in their noise assessment and Eilar Associates concur that the dryer on site is Eilar Associates, Inc. - 210 South Juniper Street, Suite 100, Escondido, CA 92025. 760-738-5570 • Fax 760-738-5227 Second Response to Opposition to Wash -N -Go (DR15-0037; CUP15-0023; PER16-0003) January 9, 2018 Job #B60504N5 Page 3 of 4 the primary source of noise on site, and would therefore drive the hourly noise impact, which is the metric used in the applicable noise regulations. It is important to note, however, that the fact that a noise source may not affect the hourly noise level does not mean that it is nonexistent or inaudible, but rather, that it would be expected to be that much lower than the dominant noise source that the numerical impact would not increase significantly due to their inclusion. 3. The letter states: "...the fact that the intercoms would be of brief duration, and, therefore, may not impact the average hourly noise levels, does not mean that such noises will not be disruptive and impact the residential properties." The intent of noise regulations, including those formulated in the City of Chula Vista Municipal Code, is to reasonably protect noise - sensitive receivers from excessive noise impacts. It is the decision of those writing the regulations to decide what that entails, considering the subjective nature of noise and the fact that noise impacts that are considered "disruptive" to some individuals may be unobjectionable to others. With this in mind, the only quantifiable and objective noise limits within the Municipal Code are the hourly noise limits that have been addressed by the project noise study. Compliance with these noise limits should not be confused with total inaudibility, nor should it be taken to mean that no individuals could potentially be disturbed by a noise source. 4. The contention from the previous Eilar Associates letter that customer noise would be unpredictable has also been questioned in this response letter; however, it is important to recognize that predictability that a noise source will be present and predictability in terms of noise modeling are not the same. While there will certainly be cars idling on site, as well as the possibility of loud conversations within or around cars, car radios playing, and horns sounding, the high level of variation in these sources is what makes them "unpredictable" from a noise modeling standpoint. Differences in the potential volume of radios/conversations, the number of cars in which these noise sources are present at any given time or within an hour, the locations of cars on site while conversations are taking place/radios are playing, the variation in noise from car horns of different types of vehicles, the locations of cars when the horns are sounded or duration of the horn, the number of horns sounded in an hour, and other such factors make the formulation of a noise model considering all of these sources impractical and likely inaccurate. Additionally, as previously stated, with the dominant and more regular source of noise at the site being the car wash dryer, these intermittent noise sources would not be expected to contribute to the overall hourly noise impact at the site. The letter goes on to recommend using noise measurements from a "similarly situated car wash as a reference and create real, objective measurements." While similar noise sources would undoubtedly be present, the aforementioned variation in noise sources in not only the hours throughout the day but also what would be expected on a day-to-day basis would make capturing noise measurements that are representative of what would be experienced at the site a difficult task. More importantly, any measurements at a similar facility would likewise be impacted by not only the ambient noise environment, but also the car wash dryer system, which again, would be expected to be the source of noise that would dominant hourly average noise impacts. 5. The letter additionally states the car wash should be required have on-site operators to "police the facility" in an attempt to control customer noise. This is a City decision and will not be addressed by Eilar Associates. The letter further states that the project could Eilar Associates, Inc. • 210 South Juniper Street, Suite 100, Escondido, CA 92025. 760-738-5570 • Fax 760-738-5227 Second Response to Opposition to Wash -N -Go (DR15-0037; CUP15-0023; PER16-0003) January 9, 2018 Job #B60504N5 Page 4 of 4 incorporate a taller sound barrier, such as what is proposed adjacent to the commercial property (to the east of the tunnel). As Eilar Associates has reviewed the noise study and continues to feel that the study sufficiently addresses the necessary noise requirements with the currently proposed six-foot high noise barrier to the west of the tunnel, requiring the project to include a sound barrier of increased height at residential properties would again be the decision of City staff. 6. The final point of the letter again refers to CEQA and the determination of permanent, temporary, or periodic increases in ambient noise levels. A brief description of anticipated increases has been detailed in Item 1 of this response letter. The letter also states that the comparison of noise impacts to the noise ordinance (Municipal Code) standards is "a separate inquiry" from CEQA and CUP findings. However, as further detailed in Item 1, CEQA refers to Lead Agencies to set appropriate standards, and the CUP prerequisites present a subjective standard that is not quantifiable and therefore unenforceable from a noise perspective. For the reasons detailed above, it continues to be the opinion of the undersigned that the project noise study sufficiently demonstrates the project's compliance with the applicable noise regulations of the City of Chula Vista. Please call if you have any questions or require additional information. Sincerely, EILAR ASSOCIATES, INC. ' Jo an Brothers, Principal Acoustical Consultant Amy Hoof` enior Acoustical Consultant iv Attachment: Principles of Decibel Addition Eilar Associates, Inc. • 210 South Juniper Street, Suite 100, Escondido, CA 92025. 760-738-5570 • Fax 760-738-5227 Subject: Principles of Decibel Addition To determine the combined logarithmic noise level of two known noise source levels, the values are converted to the base values, added together, and then converted back to the final logarithmic value, using the following formula: Lf, =101og(IO'""10+10 2/10+10LN/10) where Lc = the combined noise level (dB), and LN = the individual noise sources (dB). This procedure is also valid when used successively for each added noise source beyond the first two. The reverse procedure can be used to estimate the contribution of one source when the contribution of another concurrent source is known and the combined noise level is known. These methods can be used for LEQ or other metrics (such as LDN or CNEL), as long as the same metric is used for all components. Further explanation may be provided upon request.