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Environmental Assessment - Radio Tower MitigationKalispell City Airport Environmental Assessment — Radio Tower Mitigation. Introduction Two radio towers just over one mile southeast of the Kalispell City Airport have been officially declared a "hazard to air navigation." (10/5/99 Memorandum, Flight Standards District Office, Helena, Montana) The FAA has set mitigation of these avigational hazards as a precondition to federal funding assistance for construction at Kalispell City Airport. (8115101 meeting at FAA Helena including FAA, City of Kalispell, & RPA ) FAA approved mitigation options include lowering towers below Part 77 surfaces, or complete removal, but not strobing. (8/15/01 meeting at FAA Helena ) The pair of towers are 325 feet tall and separated by just under 1000 feet. Each tower is surrounded by guy wires and buried wire "spokes" extending out about 406 feet in all directions from the base. A 35-acre "footprint" is necessary for this station to continue broadcasting with their licensed directional pattern. The paired towers in an alignment of 240-degrees from true north allow a directional broadcast signal that more efficiently covers the length of Flathead Valley. There are a number of options for mitigating the radio towers penetrating the present and future airport's airspace including lowering, relocating, or removing. Lowering relies on replacing each tall tower with an array of four substantially shorter towers, called a "paran array." Relocating could be accomplished by constructing a completely new set of broadcast towers or by sharing an existing tower and constructing a single new tower. Removing the existing towers by outright purchase could be accomplished through a willing sale by the current owner or by condemnation. With a willing owner, the station's license could be down graded, but continue transmitting from a single tower that would open more options for relocation. Replacement with Short Towers The towers would need to be lowered to less than 150 feet to avoid penetrating the Part 77 surfaces. RPA contacted the broadcast engineering consultant (Mr. Timothy Cutforth, VIR James P.C.) that completed the radio tower assessment for the 1998 Master Plan. He claims that an array of four 100' towers, called a "paran" antenna, could replace each of the taller towers, and provide nearly identical broadcast coverage without the height. The two current towers operate together to produce a directional broadcast signal that could theoretically be duplicated by two paran arrays that would stand well below the critical airspace on the existing tower site. The FCC has licensed only two stations using paran antennas, both of these non -directional broadcast stations. (12/13/01 phone conversation with Mr. Edward Labatski, FCC) The two stations are licensed as "day time only," though they broadcast at sublicense power through the night. A recent submission to the FCC for a 24-hour non -directional paran array was referred to the FCC's engineering division as an "experimental" use that would require a 6-12 month review (3/27/02 phone conversation with Mr. Timothy Cutforth, VIR James P.C.) Furthermore, the FCC "has not authorized directional use of paran antennas to date." (12/18/01 phone conversation with Mr. Son Nguyen, FCC) Convincing the FCC to license an experimental technology could be a risky, expensive, and time-consuming task. Replacing KGEZ towers with paran arrays to duplicate their existing broadcast pattern would require clearing two hurdles with the FCC that have yet to be cleared in the US. While a directional broadcast by paran antennas is theoretically possible and would eliminate the hazards of the current tall towers, it will not be considered as a practical mitigation option due to its current lack of acceptance by the FCC. Tower Relocation Tower relocation involves constructing one or two towers of about 300 feet in height at a site removed from the present towers. There are two main options for tower relocation: constructing one and sharing one (existing) tower, or constructing two new towers. With either option the pair of towers would need to be located within a very specific area as defined by a broadcast engineer's study during the 1998 Master Planning Study. Tower sharing could save an estimated $43,000 of tower construction costs, but cost $15,000 to $100,000 for "diplexing" equipment necessary to operate a shared tower. A further study by a broadcast engineer would be required to better estimate a cost differential. Three main concerns arise with construction of new towers: creating a hazard to aviation where none previously existed, distracting from scenery, and the practical problem of supplying broadcast power. Construction of one or two towers in the immediate vicinity of an existing tower would address all three of these issues, even if tower sharing were not employed. The hazard to aviation and visual "noise" would be altered from a single tower to a tight array of two or three towers. To share an existing tower requires a acceptably located tower with a willing owner. There is only a single broadcast tower within the allowable area. The 300'-tall FM broadcast tower is located 2.5 miles WNW of the community of Somers. The tower is owned and operated by KOFI. Station owners Dave Ray and Mike Jorgensen were contacted and showed marginal interest in use of their tower in exchange for financial incentives. The KOFI tower is of suitable height and configuration that collocation may be feasible. It is possible, but could be difficult to satisfy the FCC requirement for positioning a new tower base within 10- to 20-vertical feet of the existing tower. In addition, the area is rather dry and rocky, so the ground radial system would not provide nearly the capacitance quality associated with valley -bottom soils. Alignment and spacing requirements produce two possible locations for the new tower, an upslope and down slope option. The location down slope could produce a screened inferior signal to the south and it conflicts with an existing road. To erect a new tower at this location and relocate the conflicting road would involve ten properties. It is an inferior option in complexity, ramifications, and outcomes. The upslope option would provide a less obstructed transmission to the south. It would affect only seven properties and not change any roadways. There is a potential tower site about 700 feet down the hill from the KOFI tower where the natural terrain is quite favorable to the required tower alignment. It would be easily accessible with short extensions of the existing road and power line, and would affect only two property owners. This location would have terrain extending to 300 feet above the tower bases about 1/3 of a mile south of the proposed towers. A broadcast engineer's analysis would be required to determine if this would have significant detrimental effects to the transmitter pattern. This is a preferred option in terms of simplicity of approach and arrangement, but could have shortcoming in duplicating the current KGEZ broadcast pattern. A second site for a pair of new full -height towers straddles the knob a quarter mile from KOFI's FM antenna. It would be slightly more difficult to access and would affect 5 properties. This location would probably provide superior coverage to the existing broadcast site in all directions. Constructing a new pair of towers on the valley floor would require purchase of 35 acres at the appropriate alignment and some "uneconomic remnants." The location of these towers would have to be chosen carefully to avoid a number of airways and flight patterns (see Figure xxx). Costs would include construction of two new towers and associated ground systems with a microwave link to the existing station studio. The total costs including about 50 acres of land, towers and supporting equipment, microwave link and broadcast engineering would total roughly half a million dollars. It is anticipated that constructing towers where none currently exist could raise esthetic concerns and local opposition that could require environmental analysis beyond the scope of this study. The land investment could be partially repaid by leasing out the non -critical portion for agricultural production or livestock grazing. Tower and Business Removal The City could enter into negotiations with the current KGEZ station owner to agree on an acceptable price for dissolution of his business. Meeting no success on this front, State law allows the taking for the public good of towers.deemed "airport hazards" with reasonable compensation. Creative Alternatives Up to this point all discussion has centered on meeting federal guidelines for relocation assistance including providing "equal or better" broadcast capabilities to KGEZ. If the city chooses an option that does not meet the "equal or better" condition with no interruption of service they guarantee there will be no federal reimbursement for any tower relocation options. The FAA currently has refused to reimburse the city for tower relocation expenses, requiring this as a precondition for FAA participation. This policy could change given congressional or other significant input into the FAA. It could be significantly less expensive to the city to relocate the existing facilities, rather than construct new. The current facilities are best described as "serviceable;" they are worth far less than brand new replacements. The obvious problem with moving the existing broadcast facilities is that the station would have to cease broadcasting during the relocation. A negotiated payment would be required to fairly compensate the KGEZ business for damages due to this temporary shutdown. The city could pay a fixed sum in exchange for KGEZ agreeing to downgrade their existing license to non - directional broadcast. To broadcast at the currently licensed frequency, the broadcast tower must be: 1) about 325% 2) about 275' with an additional expense for "toploading", or 3) use an array of four 100'-tall paran towers. The paran array would require a further degradation of licensing to "daytime", even though sub -license power broadcast could continue through the night. A reduction in broadcast license to a "non - directional" with a change in broadcast area would allow much more freedom in selecting an antenna site. If the city purchased the KGEZ business outright, they would have the option of recouping a portion of their purchase price by exercising any of the preceding options and selling the resulting station, or selling to a buyer who agreed to pursue one of the creative alternatives. Recommendation The city should attempt by reasonable measures to purchase the KGEZ towers and associated business. Should the owner be unwilling, the city should pursue condemnation of this "hazard to navigation" that endangers aviators and severely limits the development of their public facility. Meeting success on either of these fronts, the City could recoup a portion of their investment by reselling the business under the condition that all facilities are removed from the current location. F:IAIRPORTSIKALISPEL1EnvirnmtlradT WR S.doe