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HomeMy WebLinkAbout08.31.2021 HDR Noise Monitoring Memo 1 | P a g e Memo Date: August 31, 2021 Project: 900 King Street Redevelopment Project To: Village of Rye Brook Board of Trustees From: HDR: Noemi Castillo and Ronald Ying Subject: Construction Continuous Noise Monitoring Options Introduction At the request of the Village of Rye Brook (Village), Henningson Durham & Richardson Architecture and Engineering, PC (HDR) prepared this follow-up memorandum based on discussions held at the August 10th Village Board of Trustees meeting to further examine continuous noise monitoring along the western property boundary during construction of the property located at 900 King Street (Site). HDR has familiarity with operating noise monitors and reviewing noise monitoring data on construction projects. This memorandum summarizes the construction noise monitoring and reporting options available for continuous noise monitoring at one or more of the noise-sensitive receptors located adjacent to the Site for the approximately 30 months construction duration. If required by the Village, continuous noise monitoring would be performed to ensure noise mitigation measures identified in the Construction Management Plan (CMP) are effective and preset noise level thresholds are not exceeded during construction. Any final decisions on the construction continuous noise monitoring will need to be added to the 900 King Street Redevelopment Project CMP prior to the start of demolition and construction activities, including: • The selected continuous noise monitoring location(s), considered to be permanent during the duration of construction, including placement of the monitoring equipment (i.e., utility pole, semi-permanent contractor installed location) • The power source for the selected continuous noise monitoring system (e.g., grid power or solar with battery) • Logistics regarding property access to install and operate the monitor, including access to download date and maintain monitor and power source, as needed. • Security and protection of the continuous noise monitoring system. • The continuous noise monitoring thresholds for the hourly noise measurements (e.g., greater than 65 dBA) and instantaneous noise measurements. • Responsibility for maintaining the continuous noise monitoring system, including downloading data, annual calibrations, and, if applicable, battery replacement. • Communication process, including who will receiver alerts from the noise monitoring system. 2 | P a g e • Investigating and reporting exceedances of the noise monitoring thresholds. • Data reporting method and frequency (e.g., monthly or quarterly memorandums summarizing the data and any incidents) Overview The noise monitoring systems discussed in this memorandum were evaluated based on the following criteria: • Logistics • Meter Functionality • Labor and Cost Implication This memorandum provides a summary of the following two noise monitoring systems: 1. Sigicom Option 2. Larson Davis Option Costs for both noise monitoring systems are provided based on obtaining one unit for continuous noise monitoring along the western property boundary near the Arbors Condos, or obtaining three units for continuous noise monitoring near the three noise-sensitive receptors located adjacent to the Site, including the Arbors Condos to the west; the Village Hall, Police Department, and Fire Department to the east; and Blind Brook High School to the south. Where possible, AC power should be used to power the monitoring equipment and avoid disruptions in the noise monitoring due to a power loss. If AC power is not available, a solar panel and batteries for power storage would be used to power the noise monitoring system. Regardless of the option selected, if the Village decides to move forward with continuous noise monitoring during construction, the selected noise monitoring system should be installed and in operation at a minimum one week prior to the commencement of demolition and construction for the purpose of obtaining one week of existing (background) noise levels at the monitoring location(s). This data would be used to develop appropriate hourly baseline noise levels for daytime (7 AM to 10 PM) and nighttime (10 PM to 7 AM) hours at the monitoring location(s) for comparison during construction as needed. It should be noted that this background noise monitoring at the selected continuous noise monitoring location(s) is considered to be in addition to the baseline noise monitoring recommended in the Village of Rye Brook Report and Recommendations on the Site Plan Application, approved on June 24, 2021. The baseline noise monitoring recommended in the June 2021 Village of Rye Brook Report and Recommendations on the Site Plan Application should be performed at all of the Final Environmental Impact Statement (FEIS) noise-sensitive receptors. Noise Fundamentals Noise is often described as unwanted sound. The subjective perception of noise is affected by several physical characteristics: • Actual level of the sound (perceived loudness); • Distribution of sound energy among individual frequency bands in the audible range; 3 | P a g e • Duration of exposure to the sound; and • Changes or fluctuations in the sound levels during the period of exposure. The human ear does not perceive all sound frequencies equally well. Therefore, measured sound levels are adjusted or weighted to more closely correspond to human hearing. A- weighted sound decibel levels (dB(A)) most closely duplicate human perception of noise. As very few noises are constant, metrics have been developed to describe varying noise levels over extended periods of time. A commonly used metric is the equivalent-average sound level (Leq). The Leq represents a constant sound level that conveys the same sound energy as the actual fluctuating sound in a given time period. The recommended descriptor for determining noise compliance of a proposed project with regards to existing noise-sensitive receptors is the Leq(1) descriptor, which refers to the noise level in a one-hour period. Other typical noise descriptors include the Lmax, which indicates the maximum noise level during a monitoring period, and Lmin, which indicates the quietest noise level during a monitoring period. Sigicom Option The Sigicom option utilizes a Type I INFRA S50 Sound Level Meter to continuously measure the instantaneous sound pressure levels (Lmax) and hourly noise level (Leq(1)). The noise data would be logged in an INFRA Micro 4030 data logger, and data would be transferred real-time to the cloud via Sigicom’s INFRA Net system. This section discusses the Sigicom option based on logistics, functionality, and cost. Logistics A typical setup for the Sigicom option is shown in Attachment A. The INFRA Micro 4030 data logger and the lead-acid battery power supply are housed in a grey pelican case with a solar panel cover. The solar panel would charge the battery. The sound level meter and the microphone are located to the right of the pelican case housing. The sound level meter is connected to the data logger via a cable. The data logger can also be connected to an accelerometer on the ground to measure vibration should the need arise. This setup can conduct noise monitoring continuously, assuming the case is not located under a shade. The meter can be connected to a power outlet or a larger solar panel at grade to ensure continuous measurement in an area with insufficient sunlight. The meter can also alert the Village if the battery level drops under 25 percent so that a new power source can be provided, such as a battery replacement. The sound level meter and data logger set up can be vertically mounted to a pole as shown in the figure or placed on the ground. If mounted to a utility pole, coordination with the utility company would be required. The system can also be mounted on a shorter pole with an in- ground concrete base that would be installed by the contractor at the Village’s request. The vertical mounting option is preferred to avoid monitoring disruptions. The sound level meter would need to undergo an annual calibration to ensure accuracy. The calibration typically takes two weeks. A rental arrangement would need to be set up with Sigicom for the rental of an additional meter for the duration of the annual calibration. 4 | P a g e Functionality This setup would conduct continuous noise monitoring for the 30 months duration using the setup described above. The noise level data and audio recordings would be automatically transferred real-time to the cloud-based INFRA Net software. The data can only be accessed by people who have a user account. The INFRA Net system can also be used to manage notification settings and create customized data reports. Meter and data logging settings can also be changed remotely using INFRA Net. If an instantaneous (Lmax) threshold is exceeded during the monitoring, the meter would record the event and can send out a text and email alert to the Village and/or its consultant, as well as the others, such as the construction team. This option allows the exceedance to be immediately reviewed to decipher whether a construction activity or other event, such as a police siren, generated the exceedance. The Sigicom system also provides the ability to review the duration of noise exceedance in the cloud-based INFRA Net platform. Based on the hourly noise data available in the INFRA Net, the Village and/or its consultant can develop procedures if the hourly noise level (Leq(1)) exceeds the thresholds; The Village and/or its consultant can determine if additional noise mitigation measures need to be implemented during the construction. Cost The cost to purchase and operate the Sigicom hardware with INFRA Net subscription for the 30- month construction period is estimated at $16,240 for one unit or $48,720 for three units. Additional details on these estimates are provided in Attachment A. According to the vendor, field calibration is not required to maintain an accurate noise reading if the annual calibration is carried out. As such, labor costs, which are not included in the costs presented above, would be incurred during the initial installation and the annual calibration period. Additional labor costs may be required if sufficient power is not provided to the system and battery replacements and/or an additional solar panel installation is required. Please note shipping fees are not included in the estimate. Larson Davis Option The Larson Davis option is called NMS 044. The system utilizes a Type I LD 831 C sound level meter to continuously measure the instantaneous sound pressure levels (Lmax) and hourly noise levels (Leq(1)). The data would be available in the sound level meter, and a noise technician would remotely access the noise data in the meter using the Larson Davis’ G4Utility software. If the Village would like a user interface that can automatically download the data from the Larson Davis system instead of having a noise analyst remotely downloading data from the meter, an additional third party system, such as the Greenlight System, can be installed to automatically transfer the data real-time to a cloud-based user interface or remote server. This section discusses the Larson Davis option based on logistics, functionality, and cost. Logistics A typical setup for the NMS 044 is shown in Attachment B. The LD 831C sound level meter and the lead-acid battery power supply are housed in a grey pelican case. The meter is typically 5 | P a g e placed on the ground, and the microphone is located to the right of the pelican case housing. The microphone with the bird spike is connected to the sound level meter via a cable. The solar panel is also connected to the NMS 044 system to supply power for continuous monitoring. The system can also be mounted on a shorter pole with an in-ground concrete base that would be installed by the contractor at the Village’s request. The vertical mounting option is preferred to avoid monitoring disruptions. This setup can conduct noise monitoring continuously, assuming the solar panel is not located under a shade. In an area with insufficient sunlight, the meter can either be connected to a power outlet or an additional solar panel to ensure continuous measurement. The meter can also alert the Village via text and/or email if the battery level drops under a preset percentage so that a new power source can be provided, such as a battery replacement. The sound level meter would need to undergo an annual calibration to ensure measurement accuracy. The calibration typically takes two to three weeks. A rental arrangement would need to be set up with the Modal Shop for the rental of additional meters for the duration of the annual calibration. Functionality This setup would conduct continuous noise monitoring for the 30 months duration using the setup described above. If an instantaneous (Lmax) threshold is exceeded during the monitoring, the NMS 044 system would record the event and can send out a text and email alert to the Village and/or its consultant, as well as the others, such as the construction team. This option allows the exceedance to be immediately reviewed to determine the source of noise exceedance. Based on the hourly noise data available from the downloaded measurements, the Village and/or its consultant can develop procedures if the hourly noise level (Leq(1)) exceeds the thresholds; the Village and/or its consultant can determine if additional noise mitigation measures need to be implemented during the construction. The noise levels data and audio recordings would be accessible remotely in the G4Utility software. The data can only be accessed by the machine that is remotely connected to the sound level meter. The G4Utility system can change all settings in the sound level meter remotely and can produce reports that reflect the monitoring data. Alternatively, there is the potential to relay the data to a remote server using a modem. However, this would require a third party system, such as the Greenlight System, at an additional cost. The NMS system also includes the outdoor preamp, which has a built-in heater and can perform remote calibration checks. The heater can ensure accurate sound level measurement in a broad temperature range and prevent condensation. The remote calibration check eliminates the need for field calibration and can produce more accurate data. 6 | P a g e Cost The cost to purchase and operate the Larson Davis NMS 044 system for the 30-month construction period is estimated at $17,266 for one unit or $51,798 for three units. Additional details on these estimates are provided in Attachment B. Labor costs, which are not included in this estimate, would be incurred during initial installation and annual calibration. Additional labor costs would be incurred to download the data remotely using the G4Utility software. Alternatively, an add-on system can be added at an additional cost to automatically upload the data to a cloud-based user interface or remote server. Labor costs may also be required if sufficient power is not provided to the system and battery replacements and/or an additional solar panel installation is required. Other fees would include data storage and shipping. Conclusion Both options listed above offer unique selling points. The Sigicom option provides a cloud-based user interface that streamlines all data reporting and alert needs. The Larson Davis option may offer more accurate sound level measurements due to its built-in heater in the preamp and its ability to perform frequent remote calibrations. However, the Larson Davis option would require an add-on system at an additional cost to automatically upload the data to a cloud-based user interface or remote server. If communicating sound levels and alerts regularly to the stakeholders at a lower cost is the Village’s preference, the Sigicom option appears to be more suitable because it has included with the system a user interface to automatically obtain the data remotely. 7 | P a g e ATTACHMENT A - Sigicom Option Typical Setup Notes: Labor costs, which are not included in the costs presented above, would be incurred during the initial installation and the annual calibration period. Additional labor costs may be required if sufficient power is not provided to the system and battery replacements and/or an additional solar panel installation is required. Please note shipping fees are not included in the estimate. 8 | P a g e ATTACHMENT B – Larson Davis Option Typical Setup for the NMS 044 Notes: Labor costs, which are not included in the costs presented above, would be incurred during initial installation and annual calibration. Additional labor costs would be incurred to download the data remotely using the G4Utility software. Alternatively, an add-on system can be added at an additional cost to automatically upload the data to a cloud-based user interface or remote server. Labor costs may also be required if sufficient power is not provided to the system and battery replacements and/or an additional solar panel installation is required. Other fees would include data storage and shipping.