Effect Upon Nearby Fcc Licensed Rf Facilities

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APPENDIX G1

ENGINEERING REPORT CONCERNING THE EFFECT UPON NEARBY FCC LICENSED RF FACILITIES

Evans Associates Montezuma II Wind Project RF Study

ENGINEERING REPORT CONCERNING THE EFFECT UPON NEARBY FCC LICENSED RF FACILITIES DUE TO THE CONSTRUCTION OF A WIND ENERGY PROJECT In SOLANO COUNTY, CALIFORNIA “MONTEZUMA II WIND PROJECT”

ICF Jones & Stokes

August 18, 2010

By: B. Benjamin Evans, P.E. Evans Associates 210 South Main Street Thiensville, WI 53092 262-242-6000 PHONE 262-242-6045 FAX www.evansassoc.com

Evans Associates Montezuma II Wind Project RF Study

ENGINEERING REPORT CONCERNING THE EFFECT UPON NEARBY FCC LICENSED RF FACILITIES DUE TO THE CONSTRUCTION OF THE MONTEZUMA II WIND ENERGY PROJECT In SOLANO COUNTY, CALIFORNIA

ICF Jones & Stokes

I. INTRODUCTION AND RESULTS SUMMARY

This engineering report describes the results of a study and analysis to determine the locations of FCC-licensed microwave and fixed station radio frequency facilities that may be adversely impacted as a result of the construction of wind turbines in the Montezuma II wind project area in Solano County, California. This report describes impact zones and any necessary mitigation procedures, along with recommendations concerning individual wind turbine siting. All illustrations, calculations and conclusions contained in this document are subject to on-site verification1.

Frequently, wind turbines located on land parcels near RF facilities can cause one or more modes of RF impact, and may require an iterative procedure to minimize adverse effects. This procedure is necessary in order to ensure that disruption of RF facilities either does not occur or, in the alternative, that mitigation procedures will be effective. The purpose of this study report is to facilitate the siting of turbines to avoid unacceptable impact to licensed RF facilities.

Two turbine types (Siemens 2.3 MW and General Electric 2.5 MW) are being proposed for the Montezuma II project. Depending on which turbine model is constructed, the hub height would be either 80 or 85 meters. The blade radius would be 50.5 meters, thus the maximum total height of the turbine from ground level to the tip of the blade in the 12 o’clock position would be 135.5 meters. The wind turbine farm occupies a land parcel approximately 24 kilometers southeast of Fairfield, California.

A specific turbine layout has been submitted for analysis. Therefore, this report will address potential impact to RF transmitting facilities due to the turbines as they are presently sited.

1 The databases used in creating the attached tables and maps are generally accurate, but anomalies have been known to occur. An on-site verification survey is suggested as part of the due diligence process.

Evans Associates Montezuma II Wind Project RF Study

Using industry standard procedures and FCC databases, a search was conducted to determine the presence of existing microwave paths crossing the Montezuma II property, as well as other RF facilities within or adjacent to the identified area. The overall view of the turbine area showing microwave paths and land mobile stations is shown in Figure 1.

Figure 1 – Overview of Turbine Area with Microwave Paths & Land Mobile Stations

The FCC database search revealed several microwave links in the area, but only two of them appear to cross near where the turbines are to be located (WLL763/WLR685) and WQAP211/WQHV882).

In addition, one land mobile base station near the turbine arrays has been identified.

Evans Associates Montezuma II Wind Project RF Study

A detailed view of the turbine area is shown in Figure 2 below:

Figure 2 – Detail of Turbine Analysis Area

Figure 2 above also shows the position of WQHG573, the closest land mobile facility to the turbine group. This station is more than 1,000 meters from the nearest turbine. In the opinion of this consultant, the aggregate impact to this licensed facility would not be significant.

Evans Associates Montezuma II Wind Project RF Study

Figure 3 - Microwave Path WQAP211/WQHV882

The microwave path shown above directly crosses the location of Turbine 23 and comes close to Turbine 21. However, impact to this path is not expected because the microwave beam is high above the turbines’ blade sweeps, as illustrated above. The green shaded area is an imaginary surface between the center line of the microwave beam and the ground directly below the microwave center line.

Evans Associates Montezuma II Wind Project RF Study

Figure 4 - Wind Turbine 23 in relation to Microwave Path WLL763/WLR685

In Figure 4 above, it appears Turbine 23 is very close to Microwave Path WLL763/WLR685, however, the Worst Case Fresnel Zone appears to be below the blade sweep. If the transmitting and receiving antenna locations of the microwave link are correct as listed in the FCC license, the link is not expected to be affected by Turbine 23. It is recommended that the transmitting and receiving antennas of this microwave path be verified by land survey so that this finding can be confirmed. The geographic coordinates listed in the FCC license for a microwave path often is not accurate for purposes of siting turbines to avoid nearby microwave paths.

Evans Associates Montezuma II Wind Project RF Study

Figure 5 - Wind Turbine 32 in relation to Microwave Path WLL763/WLR685

In Figure 5 above, it appears Turbine 32 is very close to Microwave Path WLL763/WLR685, the same link that comes near Turbine 23. However, the Worst Case Fresnel Zone appears to be below and away from the blade sweep. If the transmitting and receiving antenna locations of the microwave link are correct as listed in the FCC license, the link is not expected to be affected by Turbine 23. As mentioned previously, a land survey will confirm this finding.

Evans Associates Montezuma II Wind Project RF Study

The detailed analysis in the following paragraphs examines the pertinent FCC licensed services and supports the summary given above. This analysis assumes that all licensed services have been designed and constructed according to FCC requirements and good engineering practice. If this is not the case, the impacted facility must share responsibility with the wind turbine company for the costs of any mitigation measures2.

II. DETAILS OF ANALYSIS OF MICROWAVE LINKS

An extensive analysis was undertaken to determine the likely effect of the new wind turbine farm upon the existing microwave paths, consisting of a Fresnel x/y axis study and a z-axis (height) evaluation (see Section I). The microwave overlay is available as shape files for the GeoPlanner™, ESRI™, or Google™ programs.

Important Note: Microwave path studies are based upon third party and FCC databases that normally exhibit a high degree of accuracy and reliability. Although Evans performs due diligence to ensure that all existing microwave facilities are represented, we cannot be responsible for database errors that may lead to incomplete results. If, in spite of our diligence, such adverse situations should occur, Evans would perform an engineering analysis at no additional cost to determine how the additional facilities could be accommodated or, if wind turbine structures are already built, determine a method to re-direct the offending beam path. It is recommended that a field engineer visit the site to visually check for anomalies.

For this microwave study, Worse Case Fresnel Zones (WCFZ) were calculated for each microwave path. The mid-point of a microwave path is the location where the widest (or worst case) Fresnel zone occurs. Possible geographic coordinate errors must be added to the Fresnel zone clearance numbers3. The radius R of the Worst Case Fresnel Zone, in meters, is calculated for each path using the following formula:

where D is the microwave path length in kilometers and FGHz is the frequency in gigahertz.

In general, the WCFZ is defined by the cylindrical area whose axis is the direct line between the microwave link endpoints and whose radius is R as calculated above. This is the zone where the siting of obstructions should be avoided.

2 For instance, some microwave paths may have insufficient ground clearances as they are presently configured.

3 Many microwave facilities were built before accurate methods were available to establish exact geographic coordinates (such as GPS). It is not unusual for database errors of up to 4 or 5 seconds to occur, which can effect the positioning of critical turbines located near Fresnel paths.

Evans Associates Montezuma II Wind Project RF Study

Evans Associates has identified 32 active microwave links that intersect or are relatively close to the project area. These links are tabulated in Table 1 for reference. The microwave paths that come close to the sites of Turbines 21, 23 and 32 are shaded in yellow in Table 1.

Evans Associates Montezuma II Wind Project RF Study

Call sign Xmit location Latitude Longitude Elevation Receive location Latitude Longitude Elevation WCFZ(m) KMT49 MOUNT VACA 38.39406 122.0988 829.1 LODI GAS STORAGE 38.17028 121.81 50.3 52.7 WNE0800 STATION 38.09297 121.8855 18.2 1799 37.9427 121.8852 589.8 10.8 WNE0802 CLAYTONHLCC 37.9427 121.8852 589.8 3599 38.09297 121.8855 18.2 10.9 WQFQ892 LODI GAS STORAGE 38.17028 121.81 50.3 MOUNT VACA 38.39406 122.0988 829.1 52.6 WQJL310 SUBSTATION 38.17122 121.8461 68.2 OPS CENTER 38.12577 121.8346 120.7 5.9 WQJL311 PORT CHICAGO 38.02125 121.9878 179.5 OPS CENTER 38.12577 121.8346 92.4 14.2 WQJL312 OPS CENTER 38.12577 121.8346 92.4 PORT CHICAGO 38.02125 121.9878 179.5 14.0 WQJL312 OPS CENTER 38.12577 121.8346 120.7 SUBSTATION 38017122 121.8461 68.2 5.8 KBK64 CLAYTON HILL 37.9427 121.8852 597.4 VACA DIXON SUB 38.39961 121.9213 49.7 24.4 KMD34 DIABLOMT 37.8813 121.9155 1179.5 253 38.57572 121.4977 85 30.6 KMD35 SACTODCMWCENTER 38.57575 121.4977 85 2055 37.8813 121.9155 1179.5 30.9 KMT32 MT VACA 38.39547 122.1 83105 Rio Vista 38.15936 121.7058 38.7 22.0 KNF41 CLAYTON HILL 37.9427 121.8852 597.4 SACRAMENTO SVC CTR 38.52572 121.3883 40.2 29.4 KNG36 VACA DIXON SUB 38.39961 121.9213 49.7 CLAYTON HILL 37.9427 121.8852 597.4 24.9 KNG40 SACRAMENTO SC 38.52572 121.3883 40.2 Clayton Hill 37.9427 121.8852 597.4 29.6 WGX449 DIABLO 37.89325 121.9002 1090.3 KROY 38.54322 121.4291 29.6 53.4 WGX450 KROY 38.54322 121.4291 29.6 DIABLO 37.89325 121.9002 1090.3 54.1 WHY635 VOLLMER PK 37.88277 122.2208 587.1 WALNUT GROVE 38.24722 121.5019 39.9366 28.3 WLL763 VINE HILL 38.02989 122.0023 195.7 RIO VISTA 38.15973 121.7061 56.1 14.5 WLR685 RIO VISTA 38.15964 121.7061 56.1 HWY 12/113 38.18908 121.8152 88.4 8.5 WLR685 RIO VISTA 38.15964 121.7061 56.1 VINE HILL 38.02989 122.0023 195.7 14.5 WLU612 CEMENT HILL 38.29897 121.9991 285 RIO VISTA 38.16514 121.7266 51.2 14.1 WMN679 RIO VISTA 38.16514 121.7268 51.2 CEMENT HILL 38.29897 121.9991 285 14.1 WPJE264 HWY 12/113 38.18908 121.8152 88.4 RIO VISTA 38.15964 121.706 56.1 8.4 WPOT265 Diablo South 37.88172 121.9191 1128.5 Maaco Tower 38.60625 121.4431 33.5 30.9 WPOT974 BA00363A RIO 38.15945 121.7061 48.1 BA00362A HWY 38.18908 121.8153 91.4 6.2 WPOT975 BA00362A HWY 38.18908 121.8153 91.4 BA00363A RIO 38.15945 121.7061 48.1 6.5 WPTP325 RIO VISTA 38.15936 121.7058 38.7 MT. VACA 38.39547 122.1 831.5 22.3 WPZU838 Garden Highway CA 38.60917 121.5556 36.6 Mt. Diablo CA 37.88158 121.9191 1101.1 30.7 WPZU839 Mt. Diablo CA 37.88158 121.9191 1101.1 Garden Highway CA 38.60917 121.5556 36.6 30.5 Copyright 2010 Page 10

Evans Associates Montezuma II Wind Project RF Study

WQAP211 Mt. Diablo 37.88158 121.9191 1101.1 Garden Highway 38.60917 121.5556 36.6 30.2 WQHV882 Garden Highway CA 38.60917 121.5556 36.6 Mt. Diablo CA 37.88172 121.9191 1107.5 32.9

Table 1 – Details of Microwave Links in Area

Evans Associates Montezuma II Wind Project RF Study

From the above analysis, there appears to be no instances of blockage to a microwave path, subject to verification of the antenna sites of microwave link WLL763/WLR685. Reflections and multipath from structures further off-axis, a very rare occurrence, must be dealt with after construction, perhaps by changing microwave transmit and receive antennas to high-performance units.

It is suggested that the wind project area be physically surveyed to ensure that there are no unregistered or mis-registered antenna supporting structures or antennas.

III. ANALYSIS OF FIXED RADIO FACILITIES

3.1 Land Mobile Stations

The following land mobile stations in the area have been identified:

Latitude Longitude Ant. Ht. Call Sign Freq. (MHz) Licensee (NAD-83) (NAD-83) (m AGL) WQHG573 38.14778 121.8148 38 464.5875 High Winds LLC WQKT943 38.05778 121.7862 6.4 171.1 County of Sacramento WNGP414 38.09297 121.8869 4 169.475 State of California WQLC486 38.07472 121.7897 18 466.4875 Pacific Gas & Electric Co.

Table 2 – Land Mobile Radio Facilities near Planned Turbines

According to the presently available information, none of the facilities listed above is within a distance at which adverse effects are often observed. The closest land mobile facility, WQHG573 (highlighted in yellow above), is about 1,200 meters from the nearest turbine. In the opinion of this consultant, the aggregate impact to this licensed facility would not be significant.

It is recommended that possible additional cellular and PCS antennas be searched for during the physical site visit, since many of these antennas are not individually tabulated in the FCC records.

3.2 NTIA Notification

Operation of RF frequencies for federal government use is managed by the National Telecommunication Information Agency (NTIA), which is part of the U.S. Department of Commerce. The technical specifications for most government facilities are unavailable to the public. In order to avoid the derailment of the wind energy project due to late objections from a government agency, the NTIA should be notified of the proposed project during pre-construction planning. The NTIA has set in place a review process, wherein the Interdepartmental Radio Advisory Committee (IRAC), consisting of representatives from various government agencies, reviews new proposals for wind turbine projects for impact on government frequencies. In

Evans Associates Montezuma II Wind Project RF Study

almost all cases, no adverse impact is found, and IRAC usually issues a determination in 45 to 60 days.

Evans Associates has submitted notification of the proposed Montezuma II wind project to the NTIA on August 18, 2010, and a determination is expected in October 2010.

3.3 Cellular Facilities

The FCC database does not reflect the existence of every cellular and PCS (personal communications service) antenna located within the site boundaries. However, even if one or more cellular or PCS antennas are located near turbine sites, impact to these services is insignificant to non-existent as long as all tower structures are located farther away than 0.25 mile (0.4 kilometer) from the nearest turbine4. It is recommended that possible cellular and PCS antennas be researched during the recommended physical site visit.

IV. ANALYSIS OF BROADCAST FACILITIES

The rotating blades of a wind turbine have the potential to disrupt over-the-air broadcast TV reception within a few miles of a wind turbine. This is manifested in an analog TV picture by a flickering or tearing of the image in time with the blade rotation, which is caused by signals reflected by the blades arriving at the TV antenna along with the direct signal. This is known as “multipath interference.” However, as turbine manufacturers have replaced all-metal blades with blades constructed of mostly nonmetallic materials5, this effect has been reduced. Also, the new generation of HDTV receivers is better equipped to deal with multipath interference (which is manifested by “pixilating” or “freezing” of the digital picture) than are analog TV sets, as special circuitry is employed to suppress the reflected signal. Occasionally, however, multipath interference from one or more turbines can cause video failure in HDTV receivers, especially if the receiver location is in a valley or other place of low elevation.

Analog TV transmission ended in June of 2009, after which TV stations have been transmitting in DTV (Digital or “High Definition”). Therefore, the instant study will feature the digital mode of reception.

There are no FM or TV transmitting broadcast facilities within two miles of the Montezuma II area boundaries, according to the FCC database. There will therefore be no major disruption to the service area of these types of transmitting facilities. However, a large number of digital TV and FM stations are receivable by households within and near the turbine site, primarily from San Francisco and Sacramento.

4 Cellular antennas employ diversity and multiple receivers to compensate for any disruptions at any one location.

5 Modern turbine blades are usually constructed from glass-reinforced plastic (GRP), although they usually contain some metal for strengthening, balance and grounding.

Evans Associates Montezuma II Wind Project RF Study

4.1 TV Analysis – Digital Television Facilities

The full service digital TV facilities that are predicted to serve any portion of the turbine area are listed in Table 3.

Call Network City Channel Distance Bearing (km) KGO-TV ABC San Francisco 7 68.29 233.88 KVIE PBS Sacramento 9 32.76 58.55 KXTV ABC Sacramento 10 31.42 64.41 KNTV NBC San Jose 12 71.98 228.14 KTNC-TV Estrella TV Concord 14 27.55 197.27 KUVS-DT Univision Modesto 18 96.51 89.66 KOFY-TV Independent San Francisco 19 68.29 233.88 KMAX-TV CW Sacramento 21 31.42 64.41 KRCB PBS Cotati 23 70.64 291.49 KOVR CBS Stockton 25 31.42 64.41 KTFK-DT TeleFutura Stockton 26 31.42 64.41 KTSF Independent San Francisco 27 71.91 228.26 KPIX-TV CBS San Francisco 29 68.29 233.88 KQED PBS San Francisco 30 68.29 233.88 KMTP-TV PBS San Francisco 33 68.29 233.88 KFSF-DT TeleFutura Vallejo 34 68.29 233.88 KCRA-TV NBC Sacramento 35 33.52 60.80 KICU-TV Independent San Jose 36 70.08 183.00 KRON-TV MyNetwork TV/NBC San Francisco 38 68.29 233.88 KCNS Independent Chinese San Francisco 39 68.29 233.88 KTXL Fox Sacramento 40 32.76 58.55 KKPX-TV ION Television San Jose 41 71.82 228.29 KCSM-TV Independent Public Station San Mateo 43 68.29 233.88 KTVU Fox Oakland 44 68.29 233.88 KBCW CW San Francisco 45 68.29 233.88 KQCA MyNetwork TV Stockton 46 33.52 60.80 KTLN-TV Total Living Network Novato 47 67.36 273.21 KSPX-TV ION Television Sacramento 48 33.52 60.80 KSTS Telemundo San Jose 49 68.87 183.40 KTEH PBS San Jose 50 70.08 183.00 KDTV-DT Univision San Francisco 51 68.87 183.40

Table 3 – TV Broadcast Received Signals

Evans Associates Montezuma II Wind Project RF Study

These 31 signals represent a substantial diversity of off-air reception opportunities available to the local residents. These signals range along azimuths from northeast to east to south to southwest. It is unlikely that most, or even a majority of these signals, will be rendered unusable as a result of the proposed wind facility. This being said, the RF reception environment for TV broadcast signals in the Montezuma II area is hostile in the extreme. The topography alone causes a substantial amount of multipath reception at digital receivers within a few miles of the proposed site, as will the other nearby existing turbine farms. The multiple peaks and valleys will cause an extensive interference pattern, whether or not the turbine farm is constructed.

Although some small incremental effect is to be expected that would tend to exacerbate instances of “pixelating” or “freezing” digital pictures at some homes in the area, it is the opinion of this engineer that the existing artifacts will overwhelm such effects originating from the turbine farm.

If, in spite of these considerations, it is desired to address multipath interference affecting nearby TV receivers, there are two methods available:

1) Install a new high-gain outside TV antenna (approximately $300 each location) 2) Install a subscription satellite dish (approximately $59 per month)

Because the existing anomalies in the radio frequency environment are so extensive, an estimate concerning the number of viewer’s sites that would benefit from mitigation is not available.

4.2 FM Facilities

The tabulation in Figure 4 shows the broadcast FM facilities that are receivable with a primary service contour within and directly adjacent to the project area.

Evans Associates Montezuma II Wind Project RF Study

Call City Frequency Distance (km) Bearing (degrees) KEAR-FM Sacramento 88.1 31.8 63.1 KQED-FM San Francisco 88.5 71.9 228.6 KXPR Sacramento 88.9 33.0 58.4 KLRS Lodi 89.7 32.8 58.6 KVHS Concord 90.5 18.3 237.6 KKDV Walnut Creek 92.1 33.3 223.4 KRZZ(CP) San Francisco 93.3 71.9 228.3 KPFA Berkeley 94.1 44.7 231.0 KYLD San Francisco 94.9 71.8 228.5 KUIC Vacaville 95.3 39.0 322.2 KBWF San Francisco 95.7 71.9 228.6 KYMX Sacramento 96.1 62.1 22.3 KOIT-FM San Francisco 96.5 68.3 233.9 KSEG Sacramento 96.9 66.2 27.1 KLLC San Francisco 97.3 66.2 243.4 KISQ San Francisco 98.1 66.1 243.4 KSOL San Francisco 98.9 68.3 233.9 KMVQ-FM San Francisco 99.7 71.9 228.3 KIOI San Francisco101.3 71.9 228.6 KDFC-FM San Francisco 102.1 66.2 243.4 KSFM Woodland 102.5 52.9 9.4 KBLX-FM Berkeley 102.9 71.8 228.5 KATM Modesto 103.3 73.2 145.5 KKSF San Francisco 103.7 68.3 233.9 KHKK Modesto 104.1 60.1 149.4 KFOG San Francisco 104.5 68.3 233.9 KITS San Francisco 105.3 71.8 228.5 KMEL San Francisco 106.1 71.9 228.6 KFRC-FM San Francisco 106.9 66.1 243.4 KLVS Stockton 107.3 33.2 173.3 KSAN San Francisco 107.7 71.8 228.5

Table 4 – Broadcast FM Received Signals

Because of the “capture effect” supported by the “discriminator” in FM receivers, significant disruptions to primary FM facilities are not expected. Although the received signal may vary with the blade rotation at some listener locations in the immediate area, good quality FM radios will most likely factor out such time-varying signals.

In those relatively few cases where significant impact is caused (e.g. when a listener is located within 0.50 miles of a turbine, or when a relatively weak station is being received on a lower-

Evans Associates Montezuma II Wind Project RF Study

quality receiver), home FM radios could be connected to rooftop TV receive antennas to pull in a stronger direct signal. Mobile or portable receivers would only need to be moved slightly to pick up a stronger signal (for instance, radios using line cords for antennas).

4.3 AM Analysis

A search of the FCC’s database revealed no AM facilities within the required notification distance of 3 kilometers beyond the wind project boundaries. There should therefore be no reasonable expectations of disruptions in transmitted radiations on the AM band due to the presence of the turbines. Occasionally, depending upon ground conditions, local AM receivers may experience slight signal changes due to local effects, but such anomalies are not recognized by the FCC or the standards of good engineering practice as being a harmful effect.

V. CONCLUSIONS

The following conclusions have been reached as a result of the analysis undertaken with respect to the Montezuma II Wind project:

1. According to an analysis of licensed microwave paths in the area, no microwave paths would be affected by any of the planned turbines. However, Turbines 23 and 32 are close to microwave link WLL763/WLR685. It is recommended that the transmitting and receiving antenna sites for this link be verified by land survey to confirm that the link will not be obstructed by the turbine blades.

2. Based upon reasonable assumptions, no significant disruption is expected to any known land mobile transmitters near the project area.

3. Based upon reasonable assumptions, no significant additional disruption is expected to broadcast TV, FM or AM reception in or near the turbine area.

Respectfully Submitted,

B. Benjamin Evans, P.E. RF Impact Engineer

August 18, 2010

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APPENDIX G2 ENGINEERING REPORT UPDATE CONCERNING THE EFFECT UPON NEARBY FCC LICENSED RF FACILITIES

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Evans Associates Montezuma II Wind Project RF Study Update

ENGINEERING REPORT UPDATE CONCERNING THE EFFECT UPON NEARBY FCC LICENSED RF FACILITIES DUE TO THE CONSTRUCTION OF A WIND ENERGY PROJECT In SOLANO COUNTY, CALIFORNIA “MONTEZUMA II WIND PROJECT”

ICF Jones & Stokes

October 12, 2010

By: B. Benjamin Evans, P.E. Evans Associates 210 South Main Street Thiensville, WI 53092 262-242-6000 PHONE 262-242-6045 FAX www.evansassoc.com

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Evans Associates Montezuma II Wind Project RF Study Update

ENGINEERING REPORT UPDATE CONCERNING THE EFFECT UPON NEARBY FCC LICENSED RF FACILITIES DUE TO THE CONSTRUCTION OF MONTEZUMA II WIND ENERGY PROJECT In SOLANO COUNTY, CALIFORNIA

ICF Jones & Stokes

I. INTRODUCTION

This engineering report is an update of a previous report by this office dated August 18, 2010 which describes the results of a study and analysis to determine the locations of FCC-licensed microwave and fixed station radio frequency facilities that may be adversely impacted as a result of the construction by NextEra of wind turbines in the Montezuma II Wind project area in Solano County, California. This document has been updated using new proposed wind turbine positions overlaid upon the “blackout area” baseline study submitted by Evans on August 18th. This report describes impact zones and any necessary mitigation procedures, along with recommendations concerning individual wind turbine siting. All illustrations, calculations and conclusions contained in this document are subject to on-site verification1.

The Siemens 2.3 MW turbine is now being proposed for the Montezuma II project. The Siemens 2.3 is 80 meters from the base to the hub, and the blade diameter used will be either 93 meters or 101 meters. For the purposes of this study, the 101-meter rotor will be assumed, the total height of the structure thus being a maximum of 130.5 meters when one blade is extending vertically upward. The wind turbine farm occupies a land parcel approximately 24 kilometers southeast of Fairfield, California.

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Evans Associates Montezuma II Wind Project RF Study Update

The new turbine layout was overlaid on a GIS layer containing FCC-licensed microwave paths and land mobile sites. The FCC database was checked for new facilities added since the previous report was prepared on August 18, 2010

II. DETAILED ANALYSIS OF MICROWAVE LINKS

An extensive analysis was undertaken to determine the likely effect of the new wind turbine layout upon the existing microwave paths, consisting of a Fresnel x/y axis study and a z-axis (height) evaluation (see Section I). The microwave path is overlaid on topographic base maps, and is also available as shape overlays for the GeoPlanner™, ESRI™, or Google™ program files.

where D is the microwave path length in kilometers and FGHz is the frequency in gigahertz.

2 For instance, some microwave paths may have insufficient ground clearances as they are presently configured. 3 Many microwave facilities were built before accurate methods were available to establish exact geographic coordinates (such as GPS). It is not unusual for database errors of up to 4 or 5 seconds to occur, which can effect the positioning of critical turbines located near Fresnel paths.

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Evans Associates Montezuma II Wind Project RF Study Update

No new microwave paths have been licensed since the preparation of the August 18th report. From the information presented herein, there do not appear to be instances of blockage to microwave paths due to the Siemens turbine positions specified for Montezuma II.

It is suggested that the site be physically surveyed to ensure that there are no unregistered or mis- registered antenna supporting structures.

A detailed view of the turbines and nearby RF facilities is shown in the following Figure 1.

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Evans Associates Montezuma II Wind Project RF Study Update

Figure 1 – Detail of RF Facilities in Turbine Area

The potential impact of the microwave paths shown in Figure 1 will be discussed and illustrated in the following pages.

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Evans Associates Montezuma II Wind Project RF Study Update

Figure 2 – Microwave Path WQAP211/WQHV882 above Turbines 16 and 19

The microwave path shown above directly crosses the location of Turbine 16 and comes close to Turbine 19. However, impact to this path is not expected because the microwave beam is high above the turbines’ blade sweeps, as illustrated above. The green shaded area is an imaginary surface between the center line of the microwave beam and the ground directly below the microwave center line.

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Evans Associates Montezuma II Wind Project RF Study Update

Figure 3 – Microwave Path WLL763/WLR685 near Turbines 15 and 16

From the above figure, it is evident that neither Turbine 15 for Turbine 16 will impact the microwave path, provided that the microwave path is exactly as described in the FCC license.

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Evans Associates Montezuma II Wind Project RF Study Update

Figure 4 – Microwave Path WLL763/WLR685 near Turbine Alt5

In the above figure, it appears that Turbine Alt5 is very close to the microwave path, however, the Worst Case Fresnel Zone appears to be just beyond the blade sweep. If the transmitting and receiving antennas of the microwave link are correct as listed in the FCC license, the link is not expected to be affected by Turbine Alt5. It is recommended that the transmitting and receiving antennas of this microwave path be verified by land survey so that this finding can be confirmed.

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Evans Associates Montezuma II Wind Project RF Study Update

III. ANALYSIS OF FIXED RADIO FACILITIES

3.1 Land Mobile Stations

The new search of land mobile stations near the project area revealed an additional land mobile station near the planned turbines. The new land mobile station is WNMW325, licensed to the Sacramento Municipal Utility District. The closest planned turbine from this station is Turbine 4, whose site is 784 meters from the WNMW325 transmitter. At this distance, the electrical impact to this facility wouldn’t be insignificant.

The following land mobile stations in the area are as follows (within two miles from any turbine – marked in yellow below):

Latitude Longitude Ant. Ht. Freq. Call Sign Licensee (NAD-83) (NAD-83) (m AGL) (MHz) WQHG573 38.14778 121.8148 38 464.5875 High Winds LLC WNMW325 38.12358 121.8292 39.6 939.4875 Sacramento Muni. Utility WQKT943 38.05778 121.7862 6.4 171.1 County of Sacramento WNGP414 38.09297 121.8869 4 169.475 State of California WQLC486 38.07472 121.7897 18 466.4875 Pacific Gas & Electric Co.

Table 1 – Land Mobile Radio Facilities near Planned Turbines

As was the case previously, the transmitter for station WQHG573 is more than 1,000 meters from the nearest turbine site and thus wouldn’t be impacted to a perceptible degree. The locations of stations WQHG573 and WNMW325 relative to the turbine sites are shown in Figure 1.

III. CONCLUSIONS

The following conclusions have been reached as a result of the analysis undertaken with respect to the current Siemens turbine layout for the Montezuma II Wind project:

1. There is presently no impact upon any known FCC-licensed microwave link, provide the licenses of the microwave links near planned turbines are accurate.

2. Based upon reasonable assumptions, no significant disruption is expected to any known land mobile transmitters near the project area.

3. It is recommended that the transmitting and receiving antenna sites for microwave link WLL763/WLR685 be verified by land survey to confirm that the link will not be obstructed by the turbine blades.

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Evans Associates Montezuma II Wind Project RF Study Update

Respectfully Submitted,

B. Benjamin Evans, P.E. Communications Consultant

October 12, 2010

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