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HomeMy WebLinkAboutRS_RF Study_191216_v1.pdfRF JUSTIFICATION LETTER NOISE REPORT 222 Etruria Street, Suite 100 Seattle, WA 98109 206.839.0819 P // 206.839.0824 F August 23, 2017 Richard Cardoza Senior Project Manager LDC, Inc 20210 142nd Ave NE Woodinville, WA 98072LDC, Inc RE: SEA Cedar River COW– Property Line Noise Report Site: 1300 Bronson Way North, Renton, WA Dear Richard, This report presents a noise survey performed in the immediate vicinity of the proposed Verizon telecommunications facility at 1300 Bronson Way North in Renton, Washington. This noise survey extends from the proposed equipment to the nearest properties. The purpose of this report is to document the existing conditions and the impacts of the acoustical changes due to the proposed equipment. This report contains data on the existing and predicted noise environments, impact criteria and an evaluation of the predicted sound levels as they relate to the criteria. Ambient Conditions Existing ambient noise levels were measured on site with a Svantek 971 sound level meter on August 23, 2017. The average ambient noise level was 66 dBA, due primarily to local traffic. Code Requirements The site is located within the City of Renton Zoning jurisdiction on CA (Commercial Arterial) zoned property. The properties to the west, south and east are also zoned CA. The property to the north is zoned R-10. The proposed new equipment consists of a cell-on-wheels shelter with a mobile generator as a power supply. The equipment is expected to run 24 hours a day. Renton Municipal Code Chapter 8-7-2 adopts by reference Washington Administrative Code Sections 173-60-020, 040, 050, and 090, and further identifies all commercial properties as Class B EDNA and all residential properties as Class A EDNA Under WAC 173-60-040, noise from equipment on a Class B EDNA property is limited as follows: Class A EDNA Receiver: Noise is limited to 57 dBA during daytime hours. During nighttime, defined as the hours between 10 p.m. and 7 a.m., maximum sound levels are reduced by 10 dBA for receiving properties within Class A EDNA's. Since the equipment is expected to operate 24 hours a day, it meet the 47 dBA nighttime limit at the residential receiving properties. Class B EDNA Receiver: Noise is limited to 60 dBA 24 hours a day. Since the equipment is expected to operate 24 hours a day, it must meet the 60 dBA limit at the commercial receiving properties. RECEIVED 06/26/2018 amorganroth PLANNING DIVISION 06/13/2018 SEA Cedar River COW Page 2 Predicted Equipment Sound Levels 24-Hour Operation Equipment The proposed shelter will have two Marvair 24ACA-4CII air-conditioning units mounted on the east end of the shelter. The air conditioning units each have a sound level of 70 dBA at 5 feet and operate on a lead/lag cycle. The generator is a MQ Whisperwatt DCA-70 series which has a sound level of 65 dBA at 23 feet. Methods established by ARI Standard 275-2010 and ASHRAE were used in predicting equipment noise levels to the receiving properties. Application factors such as location, height, and reflective surfaces are accounted for in the calculations. Cell-on-wheels shelter: The shelter will be located at grade surrounded by a chain link fence. The nearest occupied residential property is approximately 150 feet north of the equipment. The nearest receiving commercial property is located approximately 75 feet east of the equipment. The following table presents the predicted sound level at the nearest receiving properties: Table 1: Predicted Noise Levels: Proposed Equipment Shelter Line Application Factor N E 1 Sound Pressure Level at 5 ft (dBA), Lp1 70 70 2 Distance Factor (DF) Inverse-Square Law (Free Field): DF = 20*log (d1/d2) -30 (150 ft) -24 (75 ft) 3 New Equipment Sound Pressure Level at Receiver, Lpr (Add lines 1 and 2) 40 46 As shown in Table 1, the cell-on-wheels shelter will meet the 60 dBA limit at the commercial receiving property and the 47 dBA nighttime code limit at the residential receiving property. Generator: The generator will be located to the south of the shelter. The nearest occupied residential property is approximately 160 feet north of the generator. The nearest receiving commercial property is located approximately 80 feet east of the generator. The following table presents the predicted sound level at the nearest receiving properties: Table 2: Predicted Noise Levels: Proposed Generator Line Application Factor N E 1 Sound Pressure Level at 23 ft (dBA), Lp1 65 65 2 Noise reduction – intervening shelter -3 3 Distance Factor (DF) Inverse-Square Law (Free Field): DF = 20*log (d1/d2) -16 (160 ft) -11 (75 ft) 4 New Equipment Sound Pressure Level at Receiver, Lpr (Add lines 1 and 2) 46 54 As shown in Table 1, the proposed generator will meet the 60 dBA limit at the commercial receiving property and the 47 dBA nighttime code limit at the residential receiving property. SEA Cedar River COW Page 3 This report has been prepared for the titled project or named part thereof and should not be used in whole or part and relied upon for any other project without the written authorization of SSA Acoustics, LLP. SSA Acoustics, LLP a ccepts no responsibility or liability for the consequences of this document if it is used for a purpose other than that for which it was commissioned. P ersons wishing to use or rely upon this report for other purposes must seek written authority to do so from the owner of this report and/or SSA Acoustics, LLP and agree to indemnify SSA Acoustics, LLP for any and all resulting loss or damage. SSA Acoustics, LLP accepts no responsibility or liability for this document to any other party other than the person by whom it was commissioned. The findings and opinions expressed are relevant to the dates of the works and should not be relied upon to represent conditions at substantially later dates. Opinions included therein are based on information gathered duri ng the study and from our experience. If additional information becomes available which may affect our comments, conclusions or recommendations SSA Acoustics, LLP reserves the right to review the information, reassess any new potential concerns and modify our opinions accordingly. Please contact us if you have questions or need further information. Sincerely, SSA Acoustics, LLP Alan Burt, P.E. ACOUSTICAL CONSULTANT PARTNER NIER REPORT HATFIELD & DAWSON THOMAS M. ECKELS, PE CONSULTING ELECTRICAL ENGINEERS TELEPHONE (206) 783-9151 STEPHEN S. LOCKWOOD, PE 9500 GREENWOOD AVE. N.FACSIMILE (206) 789-9834 DAVID J. PINION, PE SEATTLE, WASHINGTON 98103 E-MAIL pinion @ hatdaw.com ERIK C. SWANSON, PE ___________MAURY L. HATFIELD, PE THOMAS S. GORTON, PE (1942 – 2009) MICHAEL H. MEHIGAN, PE PAUL W. LEONARD, PE (1925 – 2011) JAMES B. HATFIELD, PE BENJAMIN F. DAWSON III, PE CONSULTANTS NON-IONIZING ELECTROMAGNETIC EXPOSURE ANALYSIS AND ENGINEERING CERTIFICATION PREPARED FOR Verizon Wireless “SEA CEDAR RIVER COW” TEMPORARY PERSONAL WIRELESS FACILITY 1300 BRONSON WAY N CITY OF RENTON KING COUNTY, WASHINGTON AUGUST 2016 RECEIVED 06/26/2018 amorganroth PLANNING DIVISION 06/13/2018 1 INTRODUCTION Hatfield & Dawson Consulting Engineers has been retained to evaluate the proposed temporary Verizon Wireless personal wireless communications facility “SEA CEDAR RIVER COW” for compliance with current Federal Communications Commission (FCC) and local guidelines regarding public exposure to radio frequency (RF) electromagnetic fields (EMFs). DESCRIPTION OF PROPOSED OPERATIONS Construction drawings and other information furnished by Verizon representatives show that the proposed wireless facility will have a temporary Cellular on Wheels (COW) personal wireless facility with three (3) antenna sectors, one (1) panel antenna per sector, for a total of three (3) panel antennas, and a single microwave dish antenna, all mounted atop a temporary monopole tower at 1300 Bronson Way N, Renton, in King County, Washington 98055. All of the Verizon panel antennas will be mounted and centered at approximately 36 feet above grade. The single microwave dish antenna will be centered at approximately the 38 foot level. Thus all of the temporary Verizon antennas will be well above head height for persons standing at ground level on or near the project site. All of the proposed Verizon antennas are highly directional in the vertical plane and they project the majority of the transmitted RF energy horizontally and well above all nearby buildings. Very little energy is directed downwards towards ground level or the nearest occupancies. Therefore RF exposure conditions at the project site and on adjacent properties, due to the combined contributions from all of the Verizon antennas, will be well below the FCC Maximum Permissible Exposure (MPE) Public limit, and the limits given in King County code K.C.C. 21A.26.100 “NIER exposure standards.” The operation of the temporary Verizon facility will NOT create significant RF exposure conditions in any occupancy, habitable space or publicly accessible area. Hatfield & Dawson Consulting Engineers 2 RF EXPOSURE CONDITIONS DUE TO VERIZON FACILITY Verizon RF engineers have provided the following detailed information about the Verizon personal wireless operations. The temporary facility may operate within the 700 MHz Upper Block C frequency band, the 800 MHz Cellular B frequency band, the Personal Communications Service (PCS) frequency bands, and the Advanced Wireless Service (AWS) 2.1 GHz bands. Ambient exposure conditions in nearby areas, below the elevations of the temporary antennas, on and near the project site, are expected to be a fraction of the 100% FCC Public Maximum Permissible Exposure (MPE) limit due to all Verizon operations at the site. The temporary facility is expected to be compliant with FCC guidelines regarding public RF exposure provided that direct access to the Verizon antennas is positively restricted. The Verizon wireless facility is expected to be compliant with FCC rules and guidelines regarding public RF exposure provided that direct access to the Verizon antennas is positively restricted. Note that the antennas will be mounted well above grade level and away from casual access. Construction drawings show the Verizon facility will be within a temporary fenced compound with a locking gate. Therefore site access will be restricted to authorized personnel. The RF exposure analysis is based on information provided by Verizon representatives, and known characteristics of typical wireless facilities. The analysis provides a “worst-case” model for calculating maximum “uncontrolled” (i.e., general public) RF power densities and exposure conditions. Personal wireless and microwave facilities are required to comply with the FCC “Rules & Regulations” 47 CFR §1.1310, Radiofrequency radiation exposure limits. The exposure limits shown in the table titled “NIER Exposure Standards (1) (6)” in K.C.C. 21A.26.100 “NIER exposure standards” are generally in agreement with FCC exposure guidelines and limits. In any case, since the FCC exposure limits supersede the limits shown in the aforementioned table, then compliance is determined by comparing RF field predictions with the general population/uncontrolled environment (i.e., “Public”) Maximum Permissible Exposure (MPE) limits allowed by the FCC rules and guidelines, as specified in 47 CFR §1.1310. Hatfield & Dawson Consulting Engineers 3 The FCC document Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields, OET Bulletin 65, August 1997, describes the methods established by the FCC for predicting compliance with the FCC-specified exposure limits. RF power densities and exposure levels are computed in accordance with methods described in OET Bulletin 65. The following formula derived from Equation 9 on page 21 of the bulletin has been used to calculate the power densities at specific locations: S(mW/cm2) = 0.36 x ERP (watts) / (Distance in feet)2 Theoretical calculations and worst-case exposure predictions indicate that exposure conditions due to the temporary Verizon facility at all locations near ground level will be far less than the 100% FCC Public MPE limit. In fact the Verizon facility will likely contribute less than 5% of the FCC MPE limit to the ground level exposure environment at the project site, or on any adjacent property. This conclusion is based on information supplied by Verizon representatives, and estimates of future RF exposure conditions due to the Verizon facility in specific areas with the corresponding safe exposure guidelines set forth in the FCC rules and guidelines. COMPLIANCE WITH FCC AND LOCAL REGULATIONS The FCC has determined through calculations and technical analysis that personal wireless and microwave facilities, such as those operated by Verizon, are highly unlikely to cause human RF exposures in excess of FCC guideline limits. In particular, personal wireless facilities with non- building-mounted antennas greater than 10 meters (about 33 feet) above ground level are considered to have such a low impact on overall exposure conditions that they are "categorically excluded" (i.e., exempt) from the requirement for routine environmental assessment regarding RF exposure hazards. Hatfield & Dawson Consulting Engineers 4 Thus according to FCC rules, the temporary Verizon wireless facility, with all antennas centered above the 33 foot level, is exempt from further RF safety environmental assessment because it is presumed to be in compliance with the FCC RF exposure rules and guidelines. The Verizon facility is expected to be compliant with FCC rules regarding public RF exposure provided that direct access to the Verizon antennas is positively restricted. COMPLIANCE WITH FCC REGULATIONS FOR RF EMISSIONS AND RF INTERFERENCE It is expected that the RF interaction between all of the Verizon Wireless operations will be low enough to preclude the likelihood of localized interference caused by the temporary Verizon Wireless facility to the reception of any other communications signals. All of the Verizon antennas will be sufficiently high enough, and far enough removed from all occupancies, that they are unlikely to cause interference to nearby consumer receivers or other consumer electronic devices. Transmission equipment for the Verizon Wireless facility is certified by the FCC under the equipment authorization procedures set forth in the FCC rules and guidelines. This assures that the wireless facility will transmit within the desired base-station frequency bands at authorized power levels. The temporary Verizon facility will operate in accordance with all FCC rules and guidelines regarding power, signal bandwidth, interference mitigation, and good RF engineering practices. CONCLUSIONS BASED ON FCC REGULATIONS FOR RF EMISSIONS The temporary Verizon Wireless facility “SEA CEDAR RIVER COW” will be in compliance with current FCC and local rules regarding radio frequency interference and public exposure to radio frequency electromagnetic fields provided that direct access to the antennas on the project site is positively restricted to authorized and RF cognizant workers . This conclusion is based on information supplied by Verizon representatives, and estimates of future RF exposure conditions due to the Verizon facility in specific areas with the corresponding safe exposure guidelines set forth in the FCC rules and guidelines, and in King County K.C.C. Chapter 21A.26. Hatfield & Dawson Consulting Engineers 5 The Verizon Wireless facility at the project site will comply with all FCC standards for radio frequency emissions. Verizon Wireless operations at the project site will not have a significant environmental impact as defined by the FCC Public MPE limits. Furthermore, the Verizon facility will not cause any nearby existing wireless facility to exceed non- ionizing electromagnetic radiation (NIER) exposure standards. These conclusions are based on information supplied by Verizon representatives, and estimates of future RF exposure conditions due to the Verizon facility in specific areas with the corresponding safe exposure guidelines set forth in the FCC rules and guidelines. The FCC exposure limits are based on recommendations by federal and private entities with the appropriate expertise in human safety issues. Under the Commission’s rules and guidelines, licensees are required to ensure compliance with the limits for maximum permissible exposure (MPE) established by the FCC. These limits have been developed based on guidelines provided by the Institute of Electrical and Electronics Engineers, Inc. (IEEE) and the National Council on Radiation Protection and Measurements (NCRP). Both the NCRP and IEEE guidelines were developed by scientists and engineers with a great deal of experience and knowledge in the area of RF biological effects and related issues. To ensure full compliance with FCC rules and guidelines regarding human exposure to radio frequency electromagnetic fields, the Verizon transmitters should be turned off whenever maintenance personnel are required to work in the immediate vicinity of the Verizon antenna apertures. This safety procedure should apply to all existing and future wireless transmission facilities at the project site. All instances of antenna-related work require deactivation of the subject antennas. COMPLIANCE WITH LOCAL REGULATIONS Because the Verizon Wireless facility will be in compliance with federal rules and guidelines, it will also be in compliance with local regulations concerning RF emissions per K.C.C. 21A.26.090, etc. Hatfield & Dawson Consulting Engineers 6 The following is the complete text of 47 U.S.C. § 332(c)(7)(B)(iv): “No State or local government or instrumentality thereof may regulate the placement, construction, and modification of personal wireless service facilities on the basis of the environmental effects of radio frequency emissions to the extent that such facilities comply with the Commission’s regulations concerning such emissions.” QUALIFICATIONS I am a Senior Member of the IEEE. As a partner in the firm of Hatfield & Dawson Consulting Engineers I am registered as a Professional Engineer in the States of Washington, Oregon, California and Hawaii. I am an experienced radio engineer with over 35 years of professional engineering experience whose qualifications are a matter of record with the Federal Communications Commission, and I hold an FCC General Radiotelephone Operator License PG- 12-21740. All representations contained herein are true to the best of my knowledge. 17 August 2017 David J. Pinion, P.E. Hatfield & Dawson Consulting Engineers