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HomeMy WebLinkAbout3.3Item 3.3 TOWN OF LOS ALTOS FALLS Staff Report to the Planning Commission June 3, 2010 SUBJECT: CONDITIONAL USE PERMIT AND SITE DEVELOPMENT PERMIT TO CO - LOCATE ON AN EXISTING WIRELESS COMMUNICATION FACILITY AND A VARIANCE TO LOCATE THE GROUND EQUIPMENT CABINETS WITHIN THE SETBACKS. LANDS OF PURISSIMA HILLS WATER DISTRICT (APPLICANT: T -MOBILE); 27299 ARASTRADERO ROAD; FILE # 41 -10 -CUP -VAR FROM: Nicole Horvitz, Assistant Planner APPROVED BY: Debbie Pedro, AICP, Planning Director RECOMMENDATION: That -the Planning Commission: Forward a recommendation to the City Council to approve the Conditional Use Permit, Site Development Permit, and variance, subject to the conditions of approval and findings of approval in Attachments 1 and 2. BACKGROUND The 5,292 square foot (.12 acre) property is located at the intersection of Arastradero and Purissima Road. The properly is currently used as a pump station for Purissima Hills Water District. The existing development on the site consists of a monopine, ground equipment cabinets for AT&T, a fresh water pump station, access driveway, electrical cabinets, and a portable backup generator. On February 16, 2006, the City Council approved the installation of a new monopine to be constructed by Cingular Wireless (now AT&T) and a setback variance for the monopine and associated ground equipment. The monopine is designed to accommodate co -location with one (1) additional carrier. DISCUSSION The existing wireless communications facility consists of a 92' tall monopine at the south end of the Purissima Hills Water District properly. Six (6) AT&T panel antennas are currently mounted on the pole at 86' from grade and three (3) ground equipment cabinets are along the east property line. The applicant is proposing to add an additional six (6) panel antennas (55.9" h x 13.3" w x 3.15"d) at 79' from grade and construct four (4) ground equipment cabinets along the west property line, within the property line setbacks. Staff Report to the Planning Commission Lands of Purissima Hills Water District June 3, 2010 Page 2 of 6 A radio frequency (RF) analysis for the project was submitted by Hammett & Edison, Inc, consulting engineers dated March 15, 2010. The report concludes that the proposed wireless service, along with existing AT&T wireless service, will comply with the FCC's current prevailing standard for limiting human exposure to RF energy. Therefore, no significant RF energy impact on the environment or population is expected (Attachment 4). VARIANCE Pursuant to Section 10-1.505 of the Los Altos Hills Municipal Code, structures must be located a minimum of 40' from the front property line and 30' from the sides and rear property lines. Due the shape and size of the property there is no feasible way for the applicant to comply with the setback requirements. The proposed ground equipment is 1' from the north (rear), 13' from the south (side), 12' from the south (front), and 80' from the east (side) property lines. The proposed ground equipment cabinets will be screened by the existing landscape on the site. The size and shape of the property necessitate a setback variance for any development on the site; the entire site is located in required setback. Furthermore, the siting of the existing pump house and site circulation pattern limit the siting options for the proposed ground equipment. AESTHETICS The antennas will be subject to the same aesthetic conditions as the approved AT&T monopine and antennas. The materials, colors, and design used to screen the antennas must match the AT&T antenna installation. The antennas will be painted to match the existing antennas and screened with sufficient artificial vegetation to resemble a healthy mature pine tree. WIRELESS COMMUNICATIONS FACILITIES POLICY The proposed facility is consistent with the Town's Wireless Communications Facilities Policy because it is a non-residential site, a co -location project, visual impacts are minimized by the location of the antennas and the landscape screening shields the view of the facility from off site. CONCLUSION The proposed facility will be in compliance with the Wireless Communications Facilities Policy. The applicant has submitted a report demonstrating that the proposed facility will operate within federal RF emissions standards and guidelines. CEQA STATUS The proposed application is exempt from California Environmental Quality Act (CEQA) pursuant to Section 15301(a) of the CEQA Guidelines. staff Report to the Planning Commission Lands of Purissima Hills Water District June 3, 2010 Page 3 of 6 ATTACHMENTS 1. Recommended Conditions of Approval 2. Recommend Findings of Approval 3. Applicant's statement requesting to co -locate and variance findings dated March 17, 2010 4. Radio Frequency emissions report by Hammett & Edison, Inc. dated March 15, 2010 5. Photo Simulations. 6. Wireless Communications Facilities Policy 7. Site Development Plans Staff Report to the Planning Commission Lands of Purissima Hills Water District June 3, 2010 Page 4 of 6 ATTACHEMENT 1 RECOMMEND CONDITIONS FOR A CONDITIONAL USE PERMIT FOR A WIRELESS COMMUNICATIONS FACILITY LANDS PURISSIMA-HILLS WATER DISTRICT (T -MOBILE) 27299 ARASTADRO; FILE # 41 -10 -CUP -VAR PLANNING DEPARTMENT: Any changes or revisions to the telecommunications facility or its use shall require an amendment to the applicable conditional use permit(s). Additionally, the Planning Director may schedule a review or revocation hearing before the Planning Commission regarding the use permit, if any condition of approval is not being met or the facility is being used inconsistent with the approved use or in violation of Town development codes. 2. The use permit shall expire ten (10) years from the date of approval. Renewal of the permit must be requested in writing, with appropriate fees, prior to the expiration date. 3. The Planning Department shall verify that the visual appearance and aesthetic quality of the artificial foliage and branches of the existing monopine is not significantly alerted, prior to final inspection of the facility. 4. The antennas shall be painted to the satisfaction of the Planning Director, prior to final inspection of the facility. A sample of all colors must be reviewed and approved by the Planning Department prior to issuance of the Building Permit. 5. The ground equipment units/shelters shall be painted a color, to be determined by the Planning Department, to blend with the surrounding environment prior to final inspection of the facility. A sample of all colors must be reviewed and approved by the Planning Department prior to issuance of the Building Permit. 6. The new antennas shall be screened by sufficient artificial vegetation to resemble a healthy, mature pine tree, and shall incorporate "needle socks" over the antennas to match the existing antennas. A sample of all colors and materials must be reviewed and approved by the Planning Department prior to issuance of the Building Permit. 7. No new outdoor lighting is approved. Any new lighting shall require review and approval by the Planning Department prior to installation. 8. The applicant shall submit a signed agreement to the Town, agreeing that, should the use be discontinued by the carrier, all facilities will be removed not later than 90 days after discontinuance of the use or abandonment. The agreement shall be drafted by the City Attorney, and must be signed by the applicant and submitted to the Town prior to acceptance of plans for building plan check. Staff Report to the Planning Commission Lands of Purissima Hills water District June 3, 2010 Page 5 of 6 9. The applicant shall not cause radiation in the frequencies allocated as primary to the amateur radio service and may be required to correct any and all future interference problems experienced by other licensed services. 10. T -Mobile or the operator of the site shall be responsible for repair or repainting of the proposed facilities in case of vandalism or wear and must do so within 72 hours of notice by the Town that a complaint has been received. 11. The communications facility shall comply with the Town's noise ordinance at all times. The applicant shall perform an acoustical analysis of the ground equipment in the equipment enclosure to demonstrate that noise emissions from the equipment is at or below 40db. A report prepared by an acoustical engineer shall be submitted to the Planning Department, prior to final inspection. ENGINEERING DEPARTMENT: 12. Any, and all, changes to the proposed Site Plan shall first be approved by the Town Engineering Department. No grading shall take place during the grading moratorium (October 15 to April 15) except with prior approval from the City Engineer. No grading shall take place within ten feet of any property line. 13. Final grading and drainage shall be inspected by the Engineering Department and any deficiencies corrected to the satisfaction of the Engineering Department prior to final approval. 14. Any, and all, areas on the project site that have the native material disturbed shall be protected for erosion control during the rainy season and shall be replanted prior to final inspection. COUNTY OF SANTA CLARA HEALTH DEPARTMENT 15. The applicant shall submit a copy of the Hazardous Materials Construction Permit to the Town, approved by the Santa Clara County Department of Environmental Health (1555 Berger Drive, Suite 300, San Jose, CA 95112, www.EHinfo.org/hazmat), prior to acceptance of plans for building plan check. CONDITIONS NUMBERS 8 and 15 SHALL BE COMPLETED AND SIGNED OFF BY THE PLANNING DEPARTMENT AND THE ENGINEERING DEPARTMENT PRIOR TO ACCEPTANCE OF CONSTRUCTION PLANS FOR PLAN CHECK BY THE BUILDING DEPARTMENT. Staff Report to the Planning Commission Lands of Purissima Hills Water District June 3, 2010 Page 6 of 6 ATTACHMENT 2 FINDINGS OF APPROVAL FOR A SETBACK VARIANCE WIRELESS COMMUNICATIONS FACLITY (T -MOBILE) LANDS OF PURISSIMA HILLS WATER DISTRICT 27299 ARASTRADERO ROAD FILE# 41 -10 -CUP -VAR 1. Because of exceptional and extraordinary circumstances applicable to the subject property, including size, shape, topography, location or surroundings, the strict application of the provisions of this Title is found to deprive such property of privileges enjoyed by other properties in the vicinity and under identical zoning classification; The small (0.12 acre), Purissima Hills Water District property is surrounded on three sides by undeveloped Stanford lands and Interstate 280. The size and shape of the property necessitate a setback variance for any development on the site; the entire site is located in required setback. Furthermore, the siting of the existing pump house and site circulation pattern limit the siting options for the proposed ground equipment. The strict application of the provisions of this Title creates a hardship by rendering the site unusable. 2. Upon the granting of the variance, the intent and purpose of the applicable sections of the Zoning Ordinance will still be served and the recipient of the variance will not be granted special privileges not enjoyed by other surrounding property owners. If this application is approved, the purpose and intent of the Zoning Ordinance is still served. The proposed location of the ground equipment is furthest from neighboring development (residence over 400' away). This would not be a grant of special privilege because the Town has granted a setback Variance for wireless proposals with previous applications and the size lots of this size are very rare in Town. In addition, the property is unique in that the adjoining properties are all used nonresidential including an interstate highway and undeveloped Stanford university lands that negate the purpose for the Town's normal setback requirements: 3. The granting of such variance will not be materially detrimental to the public welfare or injurious to the property, improvements or uses within the immediate vicinity and within the same zoning district. The granting of the Variance for encroachment into the setback would limit potential impacts to neighbors or property owners because the proposed location of the ground equipment are at the furthest distance when measured from adjacent development. The proposed antennas and ground equipment meet the FCC limits for human exposure and the installations will be completed to Building Code standards. No detriment to public welfare is anticipated. MAP 18 Attachment 3 T WILLS 21 'C' Orinda Way, #254, Olinda, CA 94563 • ervna.sufroconsufting.com Aor M`€ March 17, 2010 Town of Los Altos Hills Attn: Nicole Horvitz 26379 Fremont Road Los Altos Hills, CA 94022 Dear Ms. Horvitz: Sutro Consulting, on behalf of T -mobile, is submitting a request for a renewal to a Conditional Use Permit and Variance Application for a new wireless facility located at an existing monopine at 27299 Atrasdadero Road, in Los Altos Hills, CA. Please review the below information for property description and submittal requirements: Site No.: Zoning: Project Address Site: SF64271 IW 27299 Atrasdadero Road Assessor Parcel Number: 142-16-077 Agent Contact: Project Description Sutro Consulting Talin Aghazarian 21 'C' ®rinda Way, 9254 ®rinda, CA 94663 T -mobile is proposing to construct, operate and maintain a wireless telecommunications facility on an existing monpine at 27299 Atrasdadero Road. The proposed facility will involve adding six panel antennas mounted on an existing monopine. The antennas will be placed at approximately 82 feet on the monopine. The four Ericsson Base Transceiver Station (BTS) equipment cabinets will be placed at the northwest corner on the property and will have a 1' 2" setback from the property line. The proposed site is a collocation site. Variance Findings 1. Because of exceptional or extraordinary circumstances applicable to the subject property, including size, shape, topography, locations, or surroundings, the strict application of the ordinance is found to deprive the property of priveleges enjoyed by other properties in the vicinity and under identical zoning classifications: sutro consuitinq 21 'C' Orinda Way, #254, Orinda, CA 94563 • w ww.sui cmuhing.com The equipment cabinets require a setback variance since .the required setback is 30 feet. This setback would be impossible to comply with since the width of the. portion of the lot where the equipment is proposed is less than 30 feet. The shape of the lot is very narrow and triangular. Currently there are BTS equipment from ATT located on the same portion of the lot. 2. That upon granting the variance, the intent and purpose of the ordinance will still be served and the recipient of the Variance will not be granted special priveleges enjoyed not enjoyed by other surrounding property owners. Currently ATT is located at the site and their BTS equipment also required a variance. They were granted a variance to place their equipment 1'3" back from the property line where 30 feet is required. Tmobile's request will not be any different than the approved variance that ATT requested. 3. That granting the variance will not be materially detrimental to the public welfare or injurious to the property, improvements or uses within the immediate vicinity and within the same zoning district. The proposed request to reduce the required setback will not be detrimental to the public welfare, injurious to property or improvements or uses with the immediate vicinity and within the same zoning district. The site is built for wireless communiciations facilities, and Tmobile is requesting the same setback variance that ATT was granted. 4. That the variance will not allow a use or activity that is not expressly authorized on the zoning ordinance. This type of use is allowed by the zoning ordinance. The proposed site was built for co -location carrier uses. Safety and Compliance The proposed facility will not be detrimental to the character of development, as it will be un- staffed, having no impact on circulation systems. Furthermore, it will generate no addition, the proposed wireless telecommunications facility will operate in full compliance with all local noise, odor, smoke or any other adverse impacts to adjacent land uses. T -Mobile technology does not interfere with any other forms of private or public communications systems. Since their introduction, wireless telecommunications systems have proven to be an invaluable communications tool in the event of emergencies (traffic accidents, fires, etc.) and natural disasters (earthquakes, floods, etc.) where normal land line communications are often disrupted or inaccessible during and after an even has occurred. This service and similar technology are utilized by numerous governmental agencies that provide emergency service. Wireless telecommunications systems, including cellular telephones, have also proven to be invaluable tools in business communications and everyday personal use. 21 V Odnda Way, #254, Odnda, CA 94563 o wmi sutwonsu(6ng.com Unlike other land uses, which can be spatially determined through the General Plan, the location of wireless telecommunication facilities is based on technical requirements which include service area, geographical. elevations, alignment with surrounding sites and customer demand components. Placement within the urban geography is dependent on these requirements. Consequently, wireless telecommunication facilities have been located adjacent to and within all major land use categories including residential, commercial, industrial and open space proving to be compatible in all locations. The proposed facility will not detrimental to the character of development, as it will be un -staffed, having no impact on circulation systems. Furthermore, it will generate no noise, odor, smoke or any other adverse impacts to adjacent land uses. In addition, the proposed wireless telecommunications facility will operate in full compliance with all local, state and federal regulations including the Telecommunications Act of 1996. T -Mobile Company Information Based in Bellevue, Washington, the U.S. operations of T -Mobile International AG & Co. K.G., consists of T -Mobile USA, Inc. (formerly VoiceStream Wireless) and Powertel, Inc. (together'T- Mobile"). T -Mobile is one of the fastest growing nationwide wireless service providers, offering all digital voice, messaging and high-speed wireless data services to more than 20 million customers in the United States. The T -Mobile global brand name made its debut in the United States in July 2002, choosing California and Nevada as the first markets in the country to launch its wireless voice and data services. Here in the Bay Area, T -Mobile has purchased and taken control of the former PacBell Wireless/ Cingular System on January 5, 2005. T -Mobile offers consumers and business customers the most advanced mobile communications services available today, including voice, text messaging, and high-speed wireless data services. T -Mobile operates an all-digital, national wireless network based exclusively on GSM technology. T -Mobile holds a license in the California Market as follows: 1950.2-1964.8, 1965.2-1969.8 MHz and 1870.2-1884.8,1885.2-1889.8 MHz. Submittal Requirements (Per Development Review Package) Development Application Please see the enclosed completed development application. Letter of Authorization is also attached to show property owner's consent and signature. Mailing Labels Please see two sets of mailing labels included in the package. Antenna Master Plan Please see the enclosed master plan for the proposed site and surrounding areas. EMF Report Please see the enclosed EMF report prepared by Hammett and Edison. Photosirmlations Please see the attached photosimulations. sutr® consulting 21 'C' Odnda Way, #254, Orinda, CA 94563 • www.sutrocDnsuhing.com Plans Please see the following: 10 sets of 24x36 sets of plans. Filing Fee Please see the enclosed checks for $875 and $2,940 Variance Findings See the above letter T -Mobile test Corp. - proposed Base Station (bite No. SF54271) Attachment 4 Arastradero Road at Interstate 280 a Los Altos Hills, California Statement of Hammett & Edison, Inc., Consu ing Engineers The firm of Hammett & Edison, Inc., Consulting Engineers, has been retained on behalf of T Mobile West Corp., a personal wireless telecommunications carrier, to evaluate the base station (Site No. SF54271) proposed to be located on Arastradero Road at Interstate 280 in Los Altos Hills, California, for compliance with appropriate guidelines limiting human exposure to radio frequency ("RF") electromagnetic fields. Prevailing Exposure Standards The U.S. Congress requires that the Federal Communications Commission ("FCC") evaluate its actions for possible significant impact on the environment. In Docket 93-62, effective October 15, 1997, the FCC adopted the human exposure limits for field strength and power density recommended in Report No. 86, "Biological Effects and Exposure Criteria for Radiofrequency Electromagnetic Fields," published in 1986 by the Congressionally chartered National Council on Radiation Protection and Measurements ("NCRP"). Separate limits apply for occupational and public exposure conditions, with the latter Iimits generally five times more restrictive. The more recent standard, developed by the Institute of Electrical and Electronics Engineers and approved as American National Standard ANSJAEEE C95.1-2006, "Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to 300 GHz," includes similar exposure limits. A summary of the FCC's exposure limits is shown in Figure 1. These limits apply for continuous exposures and are intended to provide a prudent margin of safety for all persons, regardless of age, gender, size, or health. The most restrictive FCC limit for exposures of unlimited duration to radio frequency energy for several personal wireless services are as follows: Personal Wireless Service Approx. Frequency Occupational Limit Public Limit Broadband Radio (`BRS") 2,600 MHz 5.00 mW/cm2 1.00 mW/cm2 Advanced Wireless ("AWS'l 2,100 5.00 1.00 Personal Communication ("PCS") 1,950 5.00 1.00 Cellular Telephone 870 2.90 0.58 Specialized Mobile Radio ("SMR") 855 2.85 0.57 Long Term Evolution ("LTE") 700 2.33 0.47 [most restrictive frequency range] 30-300 1.00 0.20 General Facility Requirements Base stations typically consist of two distinct parts: the electronic transceivers (also called "radios" or "channels') that are connected to the traditional wired telephone lines, and the passive antennas that send the wireless signals created by the radios out to be received by individual subscriber units. The HAMMETT & EDISON, INC. CO."i C 1-r3.t6 E tiG3tiE3iEi' TM54271596 ".ti Pagel of 3 T -Mobile Vilest Corp. s Proposed Base Station (site No. SF54271) Arastradero Road at Interstate 280 • Los Altos Hills, California transceivers are often located at ground level and are connected to the antennas by coaxial cables about 1 inch thick. Because of the short wavelength of the frequencies assigned by the FCC for wireless services, the antennas require line -of -sight paths for their signals to propagate well and so are installed at some height above ground. The antennas are designed to concentrate their energy toward the horizon, with very little energy wasted toward the sky or the ground. Along with the low power of such facilities, this means that it is generally not possible for exposure conditions to approach the maximum permissible exposure limits without being physically very near the antennas. Computer Modeling Method The FCC provides direction for determining compliance in its Office of Engineering and Technology Bulletin No. 65, "Evaluating Compliance with FCC -Specified Guidelines for Human Exposure to Radio Frequency Radiation," dated August 1997. Figure 2 attached describes the calculation methodologies, reflecting the facts that a directional antenna's radiation pattern is not fully formed at locations very close by (the "near -field" effect) and that at greater distances the power level from an energy source decreases with the square of the distance from it (the "inverse square law'). The conservative nature of this method for evaluating exposure conditions has been verified by numerous field tests. Site and Facility Description Based upon information provided by T Mobile West, Corp., including preliminary zoning drawings by Michael Wilk Architecture, dated February 4, 2010, it is proposed to mount three RFS Model APXl6DWV 16DWV S -E -A20 directional panel antennas on an 921/2 -foot pole, configured to resemble a pine tree, located on the north side of Arastradero Road just east of Interstate 280 in Los Altos Hills. The antennas would be mounted with up to 2° downtilt at an effective height of about 75 feet above ground and would be oriented toward 70°T, 170°T, and 350°T. The maximum effective radiated power in any direction would be 2,510 watts, representing simultaneous operation at 1,120 watts for PCS and 1,390 watts for AWS operations. Located on the same pole are similar directional panel antennas for use by AT&T Mobility, another wireless telecommunications carrier. For the limited purpose of this study, it is assumed that carrier has installed Andrew Model TBXLHB-6565A-VTM directional panel antennas at an effective height of about 901/2 feet above ground and operates at a maximum effective radiated power of 3,000 watts, representing simultaneous operation at 1,500 watts for PCS and 1,500 watts for cellular service. HAMMETT & EDISON, INC. CO NSL UJING }:NGINEEKS TM54271596 :-%Z 1.K.ANCKC ; Page 2 of 3 `f -Mobile West Corp. - Proposed Base Station (,ete No. SF54271) Arastradero Road at Interstate 280 a Los Altos Hills, California Study Results For a person anywhere at ground, the maximum ambient RF exposure level due to the proposed T Mobile operation is calculated to be 0.00077 mW/cm2, which is 0.077% of the applicable public exposure limit. The maximum calculated cumulative level at ground, for the simultaneous operation of both carriers, is 0.39% of the public exposure limit. The maximum calculated cumulative level at the second -floor elevation of any nearby building` is 0.51% of the public exposure limits. It should be noted that these results include several `worst-case" assumptions and therefore are expected to overstate actual power density levels. No Recommended Mitigation Measures Due to their mounting locations, the T Mobile antennas would not be accessible to the general public, and so no mitigation measures are necessary to comply with the FCC public exposure guidelines. It is presumed that the two carriers will, as FCC licensees, take adequate steps to ensure that their employees or contractors comply with FCC occupational exposure guidelines whenever work is required near the antennas themselves. Conclusion Eased on the information and analysis above, it is the undersigned's professional opinion that the base station proposed by T Mobile West Corp. on Arastradero Road at Interstate 280 in Los Altos Hills, California, will comply with the prevailing standards for limiting public exposure to radio frequency energy and, therefore, will not for this reason cause a significant impact on the environment. The highest calculated level in publicly accessible areas is much less than the prevailing standards allow for exposures of unlimited duration. This finding is consistent with measurements of actual exposure conditions taken at other operating base stations. Authorship The undersigned author of this statement is a qualified Professional Engineer, holding California Registration Nos. E-13026 and M-20676, which expire on June 30, 2011. This work has been carried out under his direction, and all statements are true and correct of his own knowledge except, where noted, when data has been supplied by others, which data he believes to be correct. 0 " V1— e E-1326 March 15, 2010 William F. Ham tt, P.E. - E%P� 6r30-2011 Located at least 50 feet away, based on aerial photographs from Google Maps. HAMME`I'T & EDISON, INC. iTASL L]AG 1AUNNE RS TM54271596 �;Ax WXIIC,15r o Page 3 of 3 FCC Radio Frequency Protection Guide The U.S. Congress required (1996 Telecom Act) the Federal Communications Commission ("FCC") to adopt a nationwide human exposure standard to ensure that its licensees do not, cumulatively, have a significant impact on the environment. The FCC adopted the limits from Report No. 86, "Biological Effects and Exposure Criteria for Radiofrequency Electromagnetic Fields," published in 1986 by the Congressionally chartered National Council on Radiation Protection and Measurements ("NCRP"). Separate limits apply for occupational and public exposure conditions, with the latter limits generally five times more restrictive. The more recent standard, developed by the Institute of Electrical and Electronics Engineers and approved as American National Standard ANSUIEEE C95.1-2006, "Safety Levels with Respect to Human Exposure to. Radio Frequency Electromagnetic Fields, 3 kHz to 300 GHz," includes similar limits. These limits apply for continuous exposures from all sources and are intended to provide a prudent margin of safety for all persons, regardless of age, gender, size, or health. As shown in the table and chart below, separate limits apply for occupational and public exposure conditions, with the latter limits (in italics and/or dashed) up to five times more restrictive: Frequency Applicable Range (MHz) 0.3— 1.34 1.34— 3.0 3.0— 30 30— 300 300— 1,500 1,500— 100,000 1000 Electromaanetic Fields (f is freauencv of emission in MHz Electric Magnetic Equivalent Far -Field Field Strength Field Strength Power Density (V/m) (Alm) (mw/cm2) 614 614 1.63 1.63 100 100 614 823.81f 1.63 2.191f 100 180/1 1842/ f 823.8/f 4.89/ f 2.19/f 900/ 18011 61.4 27.5 0.163 0.0729 1.0 0.2 3.54Nrf 1.591[f %Rf/106 4f/238 f/300 f/1500 137 61.4 0.364 0.163 5.0 1.0 Occupational Exposure PCS %* � FM Cell ��all '00, Public ExpPosure 0.1 1 10 100 103 104 105 Frequency (MHz) Higher levels are allowed for short periods of time, such that total exposure levels averaged over six or thirty minutes, for occupational or public settings, respectively, do not exceed the limits, and higher levels also are allowed for exposures to small areas, such that the spatially averaged levels do not exceed the limits. However, neither of these allowances is incorporated in the conservative calculation formulas in the FCC Office of Engineering and Technology Bulletin No. 65 (August 1997) for projecting field levels. Hammett & Edison has built those formulas into a proprietary program that calculates, at each location on an arbitrary rectangular grid, the total expected power density from any number of individual radio sources. The program allows for the description of buildings and uneven terrain, if required to obtain more accurate projections. HAmwTT & EDISON, INC. CONSULTING ENGINEERS FCC Guidelines SAN PRANCsco Figure 1 RFkCALCrrd Cal-Wation Mfethodoiagy Assessment by Calculation of Compliance with FCC Exposure Guidelines The U.S. Congress required (1996 Telecom Act) the Federal Communications Commission ("FCC") to adopt a nationwide human exposure standard to ensure that its licensees do not, cumulatively, have a significant impact on the environment. The maximum permissible exposure limits adopted by the FCC (see Figure 1) apply for continuous exposures from all sources and are intended to provide a prudent margin of safety for all persons, regardless of age, gender, size, or health. lfigher levels are allowed for short periods of time, such that total exposure levels averaged over six or thirty minutes, for occupational or public settings, respectively, do not exceed the limits. Near Field. Prediction methods have been developed for the near field zone of panel (directional) and whip (omnidirectional) antennas, typical at wireless telecommunications base stations, as well as dish (aperture) antennas, typically used for microwave links. The antenna patterns are not fully formed in the near field at these antennas, and the FCC Office of Engineering and Technology Bulletin No. 65 (August 1997) gives suitable formulas for calculating power density within such zones. For a panel or whip antenna, power density S = 180 x 0.1 x P-11 in mW/CM2, OBw ,7r x D x h and for an aperture antenna, maximum power density Smax = 0.1 x 16 x h x P.,, , in mW/cm2, it x where OBW = half -power beamwidth of the antenna, in degrees, and Pnet = net power input to the antenna, in watts, D = distance from antenna, in meters, h = aperture height of the antenna, in meters, and n = aperture efficiency (unitless, typically 0.5-0.8). The factor of 0.1 in the numerators converts to the desired units of power density. Far Field. OET 65 gives this formula for calculating power density in the far field of an individual RF source: power density s = 2.56 x 1.64 x 100 x RFFZ x ERP mW/2 4xatxD2 in ' where ERP = total ERF (all polarizations), in kilowatts, RFF = relative field factor at the direction to the actual point of calculation, and D = distance from the center of radiation to the point of calculation, in meters. The factor of 2.56 accounts for the increase in power density due to ground reflection, assuming a reflection coefficient of 1.6 (1.6 x 1.6 = 2.56). The factor of 1.64 is the gain of a half -wave dipole relative to an isotropic radiator. The factor of 100 in the numerator converts to the desired units of power density. This formula has been built into a proprietary program that calculates, at each location on an arbitrary rectangular grid, the total expected power density from any number of individual radiation sources. The program also allows for the description of uneven terrain in the vicinity, to obtain more accurate projections. HAAcmTr & EDISON, INC. CONSULTING WGINEERS Methodology HESAN RANCISCO Figure 2 E Attachment 5 Proposed Proposed r-MoW7( Anw,ws AdvancSirr� Photo Sunulaaae Solutions Contact 1 925 t 202-8507 I view from Horseshoe Lane looking west at site Mobile SF54271 Arostradero Pine 27299Arostradero Road, Los Altos Hills, CA l�nl2([t y�-i !AUL-ri'�V. Attaclnnent 6 Y -► TOWN OF LOS ALTOS HILLS LosALTos1IILLs 26379 Fremont Road Los Altos Hills, CA 94022 Phone: (650) 941-7222 www.losaltoshills.ca.gov CALIFORNIA Wireless Communications Facilities Policy Amended 10/12/2006 Code Sections Section 10-1.703 (h)(2) of the Zoning Ordinance allows service uses, including "communications facilities", to be:permitted in the Town if a Conditional Use Permit is granted by the Planning Commission and City Council. Section 10-1.1007 (1) of the Code outlines findings which must be made to approve a use -permit, including the proper location of the use or facility relative to others in the vicinity, the adequacy of the site to accommodate the use, and that the facility or use will not have an adverse effect on adjacent properties. Intent: The purpose of this policy is to outline the desired criteria for siting of wireless communications facilities, generally including monopoles, related antennas, and equipment shelters. As the Town's land use is virtually entirely residential, wireless communications facilities will be most appropriately located on public or institutional sites existing within the Town. Colocation, location on or near existing buildings, and landscape screening will be desired to minimize the visual impacts of the facilities on neighbors and the public. Policy: 1. Priorities for siting - Wireless communication facilities shall generally be located on properties with priority as follows: a. Town -owned properties b. Foothill College c. Water tanks d. Other public or quasi -public facilities, such as schools or churches e. Residential properties of at least ten (10) acres 2. Siting on residential parcels - Wireless communication facilities may be permitted on properties used for residential purposes or vacant parcels intended for residential property owner provides written consent and significant visual impacts are mitigated. 3. Colocation — Colocation of wireless communication facilities with other facilities is encouraged to the maximum extend feasible, as long as the colocation is technologically compatible and does not substantially increase visual impacts. The Town will generally require as a condition of approval for any conditional use permit that the applicant permit colocation of other facilities, subject to technological constraints and Town review. Policy: Wireless Communication Facilities Page 2 3a. Applications for colocation on an existing wireless communications facility shall be subject to an administrative review provided that the following requirement is met: The colocated antennas and ground equipment shall be mounted or installed within an existing tower, building, or structure where the physical appearance of the existing facility is not altered to accommodate the additional antennas and equipment. 4. Landscape screening and color - Landscape screening shall be required by the Town to minimize the visual impacts of wireless communication facilities. Poles, antennas, and equipment buildings should be painted to blend with the surrounding environment and/or buildings to further minimize visual impacts. 5. Environmental review - A Negative Declaration will typically be prepared for review of proposed wireless communication facilities, with special attention to the visual impacts of the facilities. Categorical exemptions may be used where facilities are colocated with or would be minimal additions to existing structures, with negligible additional visual impact. 6. Antenna master plans — Any applicant for a wireless communication facility site shall submit applications, to the best of their knowledge, for all sites anticipated to be required by the carrier for a three (3) to five (5) year period, and the request shall be reviewed by the Planning Commission and the City Council as a master plan application. 7. Terms of permits and abandonment of sites — Conditional use permits for wireless communications facilities shall be established for periods not to exceed five (5) years, at which time renewal of the permit must be requested by the applicant. More frequent review of the operation of the permit may be made a condition of approval. Approval will also require a written agreement from the applicant that, should the use be discontinued by the carrier, all facilities will be removed not later then ninety (90) days after discontinuance of the use or abandonment. Such a provision shall also be included in any lease with the Town for use of Town lands for wireless communications facilities. The Town may require bonding or other surety to assure the removal of such facilities. 8. Wireless communication firms shall, at the time of application for permits, demonstrate efforts which have been mad to inform neighboring residents of the proposed facilities, such as conducting meetings, or mailing fact sheets and/or letters, etc ... to neighbors. 9. The Planning Director is authorized to reduce or waive permit fees for any wireless communications facility that is proven to expand wireless coverage in the Town and is structurally capable of colocation. 10. The Planning Director is authorized ' to administratively 'approve portable wireless communications facilities also known as cell on wheels or COWs on certain properties as specified in Policy #1 on a temporary basis. VL L