CHAPTER 3 ALTERNATIVES CONSIDERED

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1 3.0 INTRODUCTION CHAPTER 3 ALTERNATIVES CONSIDERED The existing Afton Airport parallel taxiway, with its approximate 4,360 foot length, only accommodates one half of the runway s length, and is too short to meet the design requirements and recommendations for the existing airport environment. Once a full parallel taxiway extension is constructed, the length will match that of the runway. The increased length, with proposed medium intensity taxiway lighting, will improve operational safety, reduce runway occupancy times, remove obstructions, and provide for operational flexibility in maneuvering on the ground for the flying public. Rehabilitation of the aged direct bury, stake mounted, runway lighting system will facilitate overall operational readiness. Lastly, the acquisition of land will facilitate the future relocation of the AWOS III to provide for accurate, unobstructed weather information to further improve pilot safety. All possible alternatives were reviewed to develop two viable alternatives each for the parallel taxiway extension, runway lighting rehabilitation, and the AWOS III relocation. The viable alternatives evaluated as part of this are as follows: Parallel Taxiway Extension Alternative 1A No Action; and Alternative 1B Extend Parallel Taxiway for Full Length Parallel Taxiway Rehabilitate Runway Lighting Alternative 2A No Action; and Alternative 2B Rehabilitate Runway Lighting Acquire Land for AWOS Relocation Alternative 3A No Action; and Alternative 3B Acquire Land for AWOS Relocation Figure 3-1 reflects the overall airport and general locations of the various alternatives. Afton Lincoln County Airport 21 (February, 2013 Draft)

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3 3.1 ALTERNATIVE 1A (PARALLEL TAXIWAY EXTENSION) - NO ACTION Keeping the existing parallel taxiway at its existing length, and Not constructing an extension to the existing parallel taxiway, and Not installing Medium Intensity Taxiway Lighting (MITL) and upgrading the PAPI s. This alternative explored the possibility of keeping the parallel taxiway at its existing length and not providing for any extension improvements. In its present configuration the parallel taxiway is not full length and does not provide access to or from the Runway 16 threshold unless via the runway directly. This alternative would also leave the existing taxiway reflectors in place and not install the MITL or PAPI improvements. The existing FAR Part 77 primary and transitional surface penetrations would not be corrected, or reduced with this alternative. The existing parallel taxiway is short of the FAA and WYDOT design requirements and recommendations. The No Action alternative would not provide for the needed improvements in safety regarding extending the parallel taxiway to full length that meets FAA and WYDOT design requirements and recommended criteria for those aircraft using the airport. Conclusion: Alternative 1A (No Action) does not provide for the full length parallel taxiway that is required and recommended by the FAA and WYDOT. This alternative does not remove or reduce existing obstructions, and does not provide for lighting in compliance with design criteria. 3.2 ALTERNATIVE 1B (PARALLEL TAXIWAY EXTENSION) EXTEND TAXIWAY FOR FULL LENGTH PARALLEL TAXIWAY Extending the existing parallel taxiway approximately 2,665 feet for a full parallel taxiway length of 7,025 feet, and Remove existing FAR Part 77 obstructions to the primary and transitional surface in the area of the parallel taxiway extension through grading, and Installing Medium Intensity Taxiway Lighting (MITL) to include conduit/light cans/conductor/fixtures for the full length of the parallel taxiway (7,025 feet), and Relocate existing segmented circle and lighted wind cone. This alternative extends the existing parallel taxiway approximately 2,655 feet to the north, for a full length parallel taxiway length of 7,025 feet. The construction of the parallel taxiway removes the obstruction penetrations to the FAR Part 77 primary and transitional surfaces in the area of the parallel taxiway through site grading. It also Afton Lincoln County Airport 23 (February, 2013 Draft)

4 includes the installation of MITL for the full length of the parallel taxiway to meet design standards. Lastly, the existing segmented circle and lighted wind cone are in the alignment of the proposed taxiway and would be relocated to the far side of the runway to a location in the general vicinity of midfield, just north of Papworth Lane. Reference Figure ALT 1B for additional details and the general location of the proposed improvements on the airfield. Alternative 1B (TW Extension) would provide for the needed improvements in safety regarding extending the parallel taxiway to full length to meet FAA and WYDOT design criteria and recommendations for those aircraft presently using the airport. This alternative also removes the obstruction penetrations to flight that exist with the present configuration, thus improving the safety to the flying public. The full length taxiway will also improve operational safety through the reduction in runway occupancy times, and provide for operational flexibility in maneuvering on the ground for the flying public. Conclusion: Alternative 1B (TW Extension) provides for the full length parallel taxiway that is needed to meet FAA and WYDOT design criteria and recommendations required by aircraft currently using the airport. Afton Lincoln County Airport 24 (February, 2013 Draft)

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6 3.3 ALTERNATIVE 2A (RUNWAY LIGHTING REHABILITATION) - NO ACTION Keeping the existing stake mounted lights and direct bury conductor in place, and Not installing runway caution zone lighting, Not installing any conduit for airfield conductors, and Not installing any new light cans, transformers, grounding improvements, or lighting fixtures. This alternative explored the possibility of keeping the existing runway lighting system as is and not providing for any lighting improvements. In its present configuration the runway lighting is made up of a combination of conduit/light cans (south end extension completed in 2005) and direct bury/stake mounted lights (1982 and 1996 era). While there are no identified issues at present, beyond the occasional maintenance resulting from rodent damage, the existing conductor is well beyond the 20 year design life for 4,685 feet of the runway, and close to the 20 year design life on the first extension of 535 feet. Failure of the airfield lighting circuit outside of a scheduled project can lead to expenditures outside of airport budgets, runway closures, and overall negative impacts on the airport and local community. The grounding of the existing stake mounted configuration also does not meet current FAA design requirements for grounding. There is also no caution zone lighting on the runway, in accordance with FAA design criteria. The No Action alternative would not provide for the needed lighting improvements in replacing the aged infrastructure and bringing the lighting circuit grounding and caution zone lighting into compliance with FAA design requirements. Conclusion: Alternative 2A (No Action) does not provide for the rehabilitation of the existing runway lighting in accordance with applicable FAA design criteria. 3.4 ALTERNATIVE 2B (RUNWAY LIGHTING REHABILITATION) - INSTALL LIGHTING CIRCUIT IMPROVEMENTS Replacing the existing direct bury conductor and stake mounted lights with new conduit/light cans/conductor/medium Intensity Runway Light (MIRL) fixtures, and Installing grounding improvements in accordance with FAA design criteria, and Upgrading the existing 2-box PAPI s to 4-box PAPI s (potential additive alternative), and Installing caution zone lighting in accordance with FAA design criteria. Afton Lincoln County Airport 26 (February, 2013 Draft)

7 This alternative replaces the aged portion of the runway lighting system with such improvements as conduit, light cans, conductor, MIRL fixtures, and other ancillary items. The project improves the visual vertical descent guidance information during the approach to the runway through the installation of 4-box PAPI s. Lastly, this project includes grounding improvements and caution zone lighting improvements to bring the runway lighting circuit into compliance with FAA design criteria. Completing the runway lighting circuit rehabilitation in a project provides for the coordination and proper prior planning to reduce the impacts of runway closures as much as possible on the airport and local community. Reference Figure ALT 2B for additional details and the general location of the proposed improvements on the airfield. Alternative 2B (RW Lighting Rehab.) would provide for the needed lighting improvements to replace the aged infrastructure and bring the lighting circuit grounding and caution zone lighting into compliance with FAA design requirements. Conclusion: Alternative 2B (RW Lighting Rehab.) provides for the rehabilitation of the existing runway lighting in accordance with applicable FAA design criteria. Afton Lincoln County Airport 27 (February, 2013 Draft)

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9 3.5 ALTERNATIVE 3A (AWOS LAND ACQUISITION) - NO ACTION Keeping the Automated Weather Observation System III (AWOS) in its existing location, and Not acquiring any land for siting of the AWOS. This alternative explored the possibility of keeping the existing AWOS in its existing location and not acquiring any land for its relocation. In its present location the AWOS is mounted at a height of 43 feet, 10 above the FAA height threshold. There is one existing hangar obstruction at the current height, with increased obstructions should the AWOS be lowered in its present location. The construction of future hangars in the terminal area also have the potential to impact the AWOS clear zones. The Wyoming Department of Transportation Aeronautics Division has also noted that while the Department would consider funding AWOS upgrades such as a new VHF, barometer, T / RH, UHF radios, thunderstorm sensor, tilt tower with LED lights, UPS, equipment frame, and precipitation gauge, they will not do so until FAA siting criteria are satisfied. The No Action alternative would not provide for the AWOS to meet FAA siting criteria in its existing location. The existing location may be impacted by at least one obstruction that could result in the transmittal of inaccurate weather data to pilots. Such inaccurate weather data may degrade overall pilot safety and the safety of those on the ground in the immediate vicinity of the airport. Conclusion: Alternative 3A (No Action) does not provide for siting the AWOS in accordance with FAA criteria and protecting for the necessary clear zones. 3.6 ALTERNATIVE 3B (AWOS LAND ACQUISITION) - ACQUIRE LAND FOR AWOS RELOCATION Acquiring approximately 65 acres adjacent to the airport for relocation of the AWOS III, either through fee or easement(s). This alternative provides for the acquisition of land adjacent to the airport, either in fee title or through easement(s), that meets all FAA siting criteria for the AWOS. Review of all existing airport property reflects that there are no on-site locations that exist that would meet FAA siting criteria that would not be impacted by obstructions to the AWOS clear zones. Obstructions relating to any potential siting locations on the airport are existing structures that would not be economically feasible to address as far as relocation. Acquisition of proposed property next to the airport meets AWOS clear zone requirements, with the proposed property identified on the Airport Layout Plan (ALP) for Afton Lincoln County Airport 29 (February, 2013 Draft)

10 future land acquisition for approach protection. Figure ALT 3B can be referenced for additional details and the general location of the proposed acquisition. Alternative 3B (AWOS Land) would provide the location to site the AWOS in accordance with FAA criteria and meet all AWOS clear zone requirements. Siting the AWOS to meet all FAA criteria and clear zones will also provide for an opportunity for WYDOT to perform upgrades to the AWOS for improved weather information and overall enhanced pilot safety. Conclusion: Alternative 3B (AWOS Land) provides for the siting of the AWOS in accordance with FAA criteria. Afton Lincoln County Airport 30 (February, 2013 Draft)

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