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HomeMy WebLinkAbout900 King Street AKRF Construction Noise Barrier Efficacy Assessment Report 2021-5-24 Environmental, Planning, and Engineering Consultants 440 Park Avenue South 7th Floor New York, NY 10016 tel: 212 696-0670 fax: 212 213-3191 www.akrf.com Offices in New York ● New Jersey ● Pennsylvania ● Maryland ● Connecticut May 24, 2021 Peter S. Duncan 900 King Street Owner, LLC 200 Madison Avenue, 26th Floor New York, NY 10016 Re: 900 King Street Redevelopment – Rye Brook, New York Construction Noise Barrier Efficacy Assessment Report Dear Mr. Duncan: AKRF has completed an acoustical analysis to evaluate an alternative configuration of construction site noise barriers at the 900 King Street redevelopment site in the Village of Rye Brook, New York, which were specified as a result of a construction noise analysis included in the project’s Final Environmental Impact Statement (FEIS). EXECUTIVE SUMMARY The FEIS included conservative spreadsheet estimates of noise levels during construction of the project at noise receptors surrounding the site. The FEIS construction noise analysis included the assumption of a noise barrier along the south side of the Project Site on Arbor Drive between the Main Site entrance and the southern site boundary, but found that noise levels would still potentially exceed applicable noise impact criteria at surrounding receptors. The Village’s Environmental Findings Statement (EFS) included a requirement for the erection of noise barriers along the east and west side (i.e., along the Arbors and Village Halls portions, respectively) of the Project Site in addition to implementation of the Applicant’s commitment to install a 12-foot noise barrier along Arbor Drive across from Blind Brook High School. The EFS stated that, “details on all three noise barriers to be constructed, including proposed wall height, should be provided for review and approval during PUD Site Plan review prior to mobilization and coordinated with the Village’s Special Engineering Consultant.” The EFS went on to say, “alternative noise mitigation measures that achieve the same level of mitigation may be explored by the Village Board during detailed PUD Site Plan review.” Subsequent to the issuance of the EFS, additional information about construction logistics has become available, and a more refined analysis of construction noise has been conducted based on 3D computerized noise models. Noise levels at noise receptors identified in the FEIS were determined during five (5) representative time periods over the course of construction with both a 12-foot barrier around three sides of the Project Site and a configuration that included a 12-foot barrier along Arbor Drive and no barrier along the east and west sides of the Project Site. Phases occurring for less than 3 months each and during which fewer pieces of equipment would be operating (i.e., Phases 2 and 7) were excluded from the refined analysis. 900 King Street Owner LLC 2 May 24, 2021 The purpose of the refined analysis is not to alter the FEIS construction noise analysis conclusions or the areas at which the FEIS found the potential for construction noise impacts. Rather the refined analysis is specifically intended to determine the amount to which the additional barriers required by the EFS (i.e., the east and west side barriers) would reduce construction noise levels at nearby receptors as compared to a barrier only along the south side of the Project Site. While the noise levels predicted by the refined analysis are generally consistent with those predicted by the FEIS construction noise analysis, the conclusions of the refined analysis are not based on the total projected noise levels but rather the difference between projected noise levels in each of the two barrier configurations. This difference represents the additional benefit provided by the east and west side barriers. The refined analysis indicated that a 12-foot barrier along the east and west sides of the Project Site would provide minimal or no additional noise reduction compared to a barrier only along the south side (i.e., along Arbor Drive). Based on this analysis, and in accordance with the EFS, the Applicant proposes to erect and maintain a 12-foot plywood barrier along the Project Site’s Arbor Drive frontage and a 6-foot plywood barrier along the east and west sides of the Project Site (see attached figure). ACOUSTICAL FUNDAMENTALS Oscillatory fluctuation in air pressure is referred to as sound or airborne sound. Sound pressure levels are measured in units called “decibels” (“dB”). Unwanted sound is typically referred to as noise. In order to establish a uniform noise measurement that simulates people’s perception of loudness and annoyance, the decibel measurement is weighted to account for those frequencies most audible to the human ear. This is known as the A-weighted sound level, or “dBA,” and it is the descriptor of noise levels most often used for community noise. Because the dBA sound pressure level unit describes a noise level at just one moment, and very few noises are constant, other ways of describing noise that fluctuates over extended periods have been developed. One way is to describe the fluctuating sound heard over a specific time period as if it had been a steady, unchanging sound. For this condition, a descriptor called the “equivalent sound level,” Leq, can be computed. Leq is the constant sound level that, in a given situation and time period (e.g., 1 hour, denoted by Leq(1)), conveys the same sound energy as the actual time-varying sound. Statistical sound level descriptors such as L1, L10, L50, L90, and Lx, are used to indicate noise levels that are exceeded 1, 10, 50, 90, and x percent of the time, respectively. Attenuation of sound refers to the reduction in the level of sound. Attenuation of airborne sound can occur over distance from the sound source or can occur when sound is transmitted through/around an obstacle. Estimates of façade attenuation (i.e., the reduction in sound level between the exterior of a building and the interior) in this report are quantified in dBA. NOISE LEVEL EVALUATION CRITERIA Typically, for evaluations of environmental noise, Leq(1) is the descriptor used to evaluate changes in noise level as they will be perceived by people experiencing noise. A change in Leq(1) of up to 3 dBA would be considered barely perceptible. A change of 5 dBA would be considered readily noticeable. A change of 10 dBA represents sound being a perceived as twice as loud, and a change approaching 20 dBA would represent a perceived quadrupling of apparent loudness. While responses to changes in noise level vary somewhat from individual to individual, the above relationships are used to describe the expected general perception of noise as compared to the existing conditions. As with the FEIS construction noise assessment, increases in ambient Leq(1) noise levels at receptor sites of more than 6.0 dBA resulting in total levels of more than 65 dBA over a prolonged period of time would be considered significant. These criteria are consistent with New York State Department of Environmental Conservation (NYSDEC) guidance for evaluation of noise impacts. 900 King Street Owner LLC 3 May 24, 2021 PROCEDURE OVERVIEW CONSTRUCTION NOISE MODEL Noise effects from construction activities were evaluated using the Computer Aided Noise Abatement (“CadnaA”) model, a computerized model developed by DataKustik for noise prediction and assessment. The model can be used for the analysis of a wide variety of noise sources, including stationary sources (e.g., construction equipment, industrial equipment, power generation equipment), transportation sources (e.g., roads, highways, railroad lines, busways, airports), and other specialized sources (e.g., sporting facilities). The model takes into account the reference sound pressure levels of the noise sources at 50 feet, attenuation with distance, ground contours, reflections from barriers and structures, attenuation due to shielding, etc. The CadnaA model is based on the acoustic propagation standards promulgated in International Standard ISO 9613-2. This standard is currently under review for adoption by the American National Standards Institute (“ANSI”) as an American Standard. The CadnaA model is a state-of-the-art tool for noise analysis and is approved for construction noise level prediction by the CEQR Technical Manual. Geographic input data used with the CadnaA model included site work areas, adjacent building footprints and heights, locations of streets, and locations of sensitive receptors. For each analysis period, the approximate geographic location and operational characteristics—including equipment usage rates (percentage of time operating at full power) for each piece of construction equipment operating at the proposed development site, as well as noise control measures—were input to the model. Construction trucks were included in the model for internal roads as well as roadways leading to the site. Construction worker autos were not modeled as they are not expected to be on the roads during worst-case construction activity and would not be traveling within the site simultaneously with the construction work. Delivery trucks were not modeled as stationary sources as they are required not to idle engines during unloading operations. Pile Driving (impact and vibratory), blasting, jack hammering, and rock crushing activities are not permitted absent further review by the Village’s Special Engineering Consultant and were therefore not included in the analysis. Construction equipment source strength was determined by the Lmax levels presented in Table 1 of the Federal Highway Administration Roadway Construction Noise Model (RCNM) User’s Guide. DETERMINATION OF NON-CONSTRUCTION NOISE LEVELS As in the FEIS analysis, noise generated by construction activities (calculated using the CadnaA model as described above) were added to baseline (i.e., non-construction) noise levels, including noise generated by non-construction traffic on adjacent roadways, to determine the total noise levels at each receptor location. The FEIS included measurements of baseline noise levels at locations representing the nearby noise receptors. GENERAL PROCEDURE AKRF’s procedure for evaluation of construction noise barrier configurations included the following:  Obtain the most recent detailed construction schedule, means and methods, equipment lists, and logistics diagrams;  Create a 3D model of construction-generated noise by construction phase;  Analyze predicted construction noise levels at sensitive noise receptors identified in the FEIS under two noise barrier configurations; and  Evaluate and compare effectiveness of noise reduction between the two noise barrier configurations and against the FEIS and the Village’s EFS commitments. NOISE RECEPTOR SITES Receptors identified in the FEIS as having the most potential to experience construction noise impacts were selected for the construction noise barrier analysis. These receptors are located adjacent to the Project Site 900 King Street Owner LLC 4 May 24, 2021 and planned areas of activity. At some buildings, multiple façades were analyzed as receptors. At multi- floor buildings, noise receptors at multiple elevations were analyzed. RESULTS Using the methodology previously described, construction noise levels with two separate barrier conditions were calculated for each of the receptor sites in each of the selected analysis periods. These results as well as the estimated FEIS noise levels are in Tables 1 through 5 below: Table 1 Estimated Maximum Noise Levels during Demolition (in dBA) Location Previously Reported Post-FEIS CadnaA Analysis Existing Leq FEIS Estimate of Maximum Construction Leq Arbor Drive Barrier Only (same configuration as FEIS) Arbors, Village Hall, and Arbor Drive Barrier Condition Maximum Leq Range of Increments from Existing Maximum Leq Range of Reductions from Add’l Barriers Arbor Condos 58.1 70.1 64.7 3.3 to 6.6 63.4 0.1 to 1.8 Blind Brook High School 59.0 61.5 64.6 1.6 to 5.6 64.6 0.0 Harkness Tennis Court 70.0 72.3 70.2 0.2 70.2 0.0 Rye Brook Village Police Department and Village of Rye Brook Hall 70.0 79.0 73.1 0.4 to 3.1 70.8 0.1 to 2.7 Rye Brook Firehouse 70.0 79.0 71.1 0.6 to 1.1 70.8 0.2 to 0.7 King Street Residences 68.7 72.7 70.1 0.1 to 1.4 69.4 0.0 to 0.7 Table 2 Estimated Maximum Noise Levels during Assisted Living Construction (in dBA) Location Previously Reported Post-FEIS CadnaA Analysis Existing Leq FEIS Estimate of Maximum Construction Leq Arbor Drive Barrier Only (same configuration as FEIS) Arbors, Village Hall, and Arbor Drive Barrier Condition Maximum Leq Range of Increments from Existing Maximum Leq Range of Reductions from Add’l Barriers Arbor Condos 58.1 62.9 61.3 0.9 to 3.2 61.3 0.0 to 0.2 Blind Brook High School 59.0 61.5 61.7 0.6 to 2.7 61.7 0.0 Harkness Tennis Court 70.0 71.2 70.1 0.1 70.1 0.0 Rye Brook Village Police Department and Village of Rye Brook Hall 70.0 81.8 72.8 1.4 to 2.8 72.3 0.4 to 2.1 Rye Brook Firehouse 70.0 81.8 71.4 0.5 to 1.4 71.4 0.0 to 0.1 King Street Residences 68.7 74.4 70.5 0.3 to 1.8 70.5 0.0 to 0.1 900 King Street Owner LLC 5 May 24, 2021 Table 3 Estimated Maximum Noise Levels during Independent Living Construction (in dBA) Location Previously Reported Post-FEIS CadnaA Analysis Existing Leq FEIS Estimate of Maximum Construction Leq Arbor Drive Barrier Only (same configuration as FEIS) Arbors, Village Hall, and Arbor Drive Barrier Condition Maximum Leq Range of Increments from Existing Maximum Leq Range of Reductions from Add’l Barriers Arbor Condos 58.1 67.1 61.0 0.8 to 2.9 60.8 0.0 to 0.6 Blind Brook High School 59.0 67.3 61.5 0.6 to 2.5 61.5 0.0 Harkness Tennis Court 70.0 71.8 70.1 0.1 70.1 0.0 Rye Brook Village Police Department and Village of Rye Brook Hall 70.0 75.0 70.4 0.2 to 0.4 70.4 0.0 to 0.2 Rye Brook Firehouse 70.0 75.0 70.1 0.0 to 0.1 70.1 0.0 King Street Residences 68.7 71.5 68.8 0.0 to 0.1 68.8 0.0 Table 4 Estimated Maximum Noise Levels during Independent Living South Wings Construction (in dBA) Location Previously Reported Post-FEIS CadnaA Analysis Existing Leq FEIS Estimate of Maximum Construction Leq Arbor Drive Barrier Only (same configuration as FEIS) Arbors, Village Hall, and Arbor Drive Barrier Condition Maximum Leq Range of Increments from Existing Maximum Leq Range of Reductions from Add’l Barriers Arbor Condos 58.1 67.3 62.7 1.8 to 4.6 62.7 0.0 to 0.7 Blind Brook High School 59.0 65.3 65.3 2.4 to 6.3 65.3 0.0 Harkness Tennis Court 70.0 73.1 70.3 0.3 70.3 0.0 Rye Brook Village Police Department and Village of Rye Brook Hall 70.0 72.9 70.6 0.2 to 0.6 70.6 0.0 to 0.1 Rye Brook Firehouse 70.0 72.9 70.2 0.0 to 0.2 70.2 0.0 King Street Residences 68.7 70.5 68.8 0.0 to 0.1 68.8 0.0 900 King Street Owner LLC 6 May 24, 2021 Table 5 Estimated Maximum Noise Levels during Townhouses Construction (in dBA) Location Previously Reported Post-FEIS CadnaA Analysis Existing Leq FEIS Estimate of Maximum Construction Leq Arbor Drive Barrier Only (same configuration as FEIS) Arbors, Village Hall, and Arbor Drive Barrier Condition Maximum Leq Range of Increments from Existing Maximum Leq Range of Reductions from Add’l Barriers Arbor Condos 58.1 67.3 67.5 4.5 to 9.4 66.6 0.0 to 1.4 Blind Brook High School 59.0 70.6 66.5 2.4 to 7.5 66.5 0.0 Harkness Tennis Court 70.0 70.5 70.1 0.1 70.1 0.0 Rye Brook Village Police Department and Village of Rye Brook Hall 70.0 70.2 70.1 0.1 70.1 0.0 to 0.1 Rye Brook Firehouse 70.0 70.2 70.1 0.0 to 0.1 70.1 0.0 King Street Residences 68.7 68.9 68.8 0.0 to 0.1 68.8 0.0 The noise levels calculated in the analysis described above under either barrier configuration are comparable or less than what was originally predicted in the FEIS. Where noise levels in this analysis deviate from those projected in the FEIS analysis, changes are due to refined schedule and logistics as well as more refined predictions of noise emissions from the equipment using the 3D noise model. As shown in the above tables, the calculated additional noise reduction from utilizing barriers along the Arbors, Village Hall, and Arbor Drive portions of the Project Site as compared to a sole barrier along Arbor Drive would most often be zero and would be less than 3 dBA at most. Such differences would be considered minimal to negligible. Noise barriers are most effective for reducing noise at receptors within approximately 50 feet of the barrier if the noise source, e.g., trucks, excavators, etc., are within a comparably small distance to the noise barrier. Most equipment would operate farther from the barrier for a majority of the construction period. Consequently, the benefit of the barrier is reduced as the distances between source and barrier or receptor and barrier increase. Additionally, benefit from utilizing barriers is minimized in part due to existing characteristics of the area, including topography, which sets construction noise sources at a higher elevation thereby reducing the effective height of surrounding barriers, as well as moderate to high existing noise levels at some nearby noise receptors. Attached to this report are noise level contour maps showing the difference in construction-generated Leq between the two barrier configurations during the four major construction phases. In these maps, warmer colors indicate areas where the barriers along The Arbors and Village Hall portions of the Project Site boundary provide greater noise control. As would be expected, the greatest differences are shown just outside the barriers, or “in the shadow” of the barriers. Inside the barriers, there is no difference shown (i.e., green) since the change in barrier configuration doesn’t affect noise levels inside the barriers. Additionally, at receptors located at considerable distance outside the barriers (e.g., the Arbors), there is also little or no difference between the two proposed barrier configurations, because they are located sufficiently far away from the construction noise sources that the shielding provided by the barriers do not provide much additional reduction in noise level. These maps show, consistent with Tables 1 through 5, that the barriers along the Arbors and Village Hall sides of the property do not provide substantial benefit at the nearby receptors. 900 King Street Owner LLC 7 May 24, 2021 LIST OF ATTACHMENTS A. “Illustrative Noise Barrier Configuration.” Figure showing proposed construction noise barrier configuration B. “Noise Barrier Contour Maps.” Contour maps of difference in noise levels with and without noise barriers on north and south site perimeters during each construction phase. C. “Spreadsheet of noise modeling results” D. “Direct output tables from CadnaA noise model” E. Appendix J, “Construction Noise,” of the FEIS F. “Equipment Library.” Table of noise emission level for each piece of construction information This concludes our comments at this time. If you have any questions, please feel free to contact me at ecohen@akrf.com or (646) 388-9770. Sincerely, AKRF, Inc. Libby Cohen Acoustical Consultant Daniel Abatemarco Vice President – Acoustics, Noise, and Vibration cc: Peter Feroe / AKRF, Inc.