CHAPTER 4 AFFECTED ENVIRONMENT, ENVIRONMENTAL … · existing homes within the Afton Airpark, to within approximately 240 feet. The construction of the parallel taxiway extension

Afton – Lincoln County Airport 32 (February, 2013 Draft) Environmental Assessment

CHAPTER 4

AFFECTED ENVIRONMENT, ENVIRONMENTAL CONSEQUENCES AND MITIGATION

4.0 INTRODUCTION Two different options for each of the three improvements (Parallel Taxiway Extension, Rehabilitate Runway Lighting, and Acquire Land), at the Afton – Lincoln County Airport have been proposed. The options for each of the three projects include: Parallel Taxiway Extension

1) No Action; and 2) Extend parallel taxiway for a full length parallel taxiway.

Rehabilitate Runway Lighting

1) No Action; and 2) Rehabilitate runway lighting - install lighting circuit improvements.

Acquire Land

1) No Action; and 2) Acquire land (approximately 65 acres) for AWOS relocation, either through fee

title or easement(s). The following is a summary of the analysis completed for each affected environment topic as identified in FAA Order 5050.4b, Airport Environmental Handbook for each development alternative. Refer to the following table (Table 4-1) for a summary of the affected environment topics by proposed development alternative.


Table 4-1. Matrix of Affected Environment Topics by Proposed Alternatives Affected

Environment Alternative

1A Alternative

1B Alternative

2A Alternative

2BAlternative

3A Alternative

3B

Air Quality NA Moderate NA Insignificant NA Insignificant

Biotic Resources NA Moderate NA Insignificant NA Insignificant

Coastal Barriers NA NA NA NA NA NA

Coastal Zone Management

NA NA NA NA NA NA

Compatible Land Use

NA Insignificant NA Insignificant NA Insignificant

Construction NA Moderate NA Moderate NA Insignificant

Section 4(f) Land NA Insignificant NA Insignificant NA Insignificant

Threatened and Endangered

Species NA Insignificant NA Insignificant NA Insignificant

Energy Supplies, Nat. Resources,

Sustainable Dsgn. NA Moderate NA Insignificant NA Insignificant

Environmental Justice

NA NA NA NA NA NA

Farmlands NA Insignificant NA Insignificant NA Insignificant

Floodplains NA NA NA NA NA NA

Hazardous Materials

NA NA NA NA NA NA

Historic and Archeological


Induced Socioeconomic

NA Insignificant NA Moderate NA Insignificant

Light Emissions and Visual Effects


Noise NA Moderate NA Insignificant NA Insignificant

Secondary (Induced) Impacts

NA Insignificant NA NA

Social Impacts NA Insignificant NA Insignificant NA Insignificant

Solid Waste NA Insignificant NA Insignificant NA Insignificant

Water Quality NA Insignificant NA Insignificant NA Insignificant

Wetlands NA Insignificant NA Insignificant NA Insignificant

Wild and Scenic Rivers

NA NA NA NA NA NA

Cumulative Impacts


Ratings = insignificant, moderate, significant, not applicable (NA).


4.1 AIR QUALITY Air quality assessments for proposed Federal actions are required for compliance with NEPA, the Clean Air Act of 1970 and other environment-related regulations and directives. Specific guidance for airport projects is provided in the Air Quality Procedures for Civilian Airport & Air Force Bases and its 2004 Addendum. The Air Quality Procedures for Civilian Airport & Air Force Bases indicates that:

If the level of annual enplanements exceeds 1,300,000 (or 2.6 MAP), the level of general aviation and air taxi activity exceeds 180,000 operations per year or a combination thereof, a NAAQS assessment should be considered.

The U.S. Environmental Protection Agency (EPA) has established National Ambient Air Quality Standards (NAAQS) for six criteria air pollutants: carbon monoxide (CO), ozone (O3) particulate matter (PM10), sulfur dioxide (SO2), oxides of nitrogen (NOx), and lead (Pb). The EPA operates under the General Conformity Rule regarding ambient air quality standards. The General Conformity Rule ensures that Federal actions comply with the national ambient air quality standards. In order to meet this Clear Air Act requirement, a Federal agency must demonstrate that every action that it undertakes, approves, permits or supports will conform to the appropriate regulations. FAA Order 1050.1E, Environmental Impacts: Policies and Procedures states, "The General Conformity Rule only applies in areas that EPA has designated non-attainment or maintenance.” Afton and Star Valley do not contain EPA-regulated non-attainment areas or a maintenance plan for criteria air pollutants per the EPA Green Book reports. The closest non-attainment area noted was in Lincoln County, Wyoming, approximately 40 miles to the southeast for 8 hour Ozone (2012). Other neighboring non-attainment areas include Bannock County, Idaho approximately 77 miles to the northwest for PM-10 particulates, Weber County, Utah approximately 115 miles to the southwest for carbon monoxide, and Salt Lake County, Utah approximately 150 miles to the southwest for sulfur dioxide. In 2011, the Airport had 0 passenger enplanements and 9,500 aircraft operations (ie. takeoffs and landings) according to the FAA Terminal Area Forecast. These activity levels are far lower than the thresholds described above for preparing an NAAQS assessment. The Wyoming Department of Environmental Quality Air Quality Division was contacted for comments regarding the proposed project (Appendix II). At the time of this writing there has been no response received.


4.1.1 Impacts Alternative 1A, 2A, 3A: No impacts to air quality will occur with these “No Action” alternatives. Therefore, there are no mitigation measures required for these alternatives. Alternative 1B: The extension of the parallel taxiway will move taxiing aircraft closer to existing homes within the Afton Airpark, to within approximately 240 feet. The construction of the parallel taxiway extension in and of itself is not projected to increase the amount of traffic currently using the airport. The Afton Airpark is also a residential aviation related development that currently has the main exit taxiway from the development between any proposed or existing homes and the proposed taxiway extension. Projected growth for the 20-year planning period reflects operations that are within ranges experienced at similar sized GA airports. Air pollutant issues have not been noted at those similar sized airports. Moderate construction impacts to air quality are expected during earthwork activities in Alternative 1B (TW Extension). Alternatives 2B and 3B: These alternatives involve construction of lighting improvements, or the acquisition of land for a weather station that do not produce air emissions. Therefore, there are no mitigation measures required for these alternatives. 4.1.2 Mitigation Compliance with all applicable local, State, and Federal air quality regulations and permitting requirements will be the responsibility of all contractors. Additionally, effective dust control measures, such as the application of water along haul roads and compaction, mulching, and reseeding during the post construction phase must be utilized in order to comply with the requirements of Wyoming Air Quality Standards and Regulations, Chapter 3, Section 2(f). Final plans and specifications for the project will address requirements for the contractor to maintain equipment on-site at all times that earthwork is being conducted, as well as during extended periods of no action to maintain dust control. The contractor will have to provide personnel for operation of that equipment as well. The plans and specifications will also incorporate the provisions of AC 150/5370-10F, Standards for Specifying Construction of Airports, which is FAA’s guidance to airport sponsors concerning protection of the environment during construction. 4.2 BIOTIC RESOURCES Morrison-Maierle, Inc. Environmental Group completed an on-site investigation of the Afton – Lincoln County Airport property on September 12, 2011 to examine the presence and extent of biotic resources associated with the project area. Potential affected environments in the biotic resources impact analysis include: general vegetation, plant species of concern, noxious weeds, general wildlife, wildlife species of concern, general fisheries, and fish species of concern. Threatened and endangered


species are addressed in the following Section 4.8 and wetlands are addressed in Section 4.22 of this document. Impacts to the above listed biotic communities are not anticipated to be significant for any development alternatives. Impacts to the above listed biotic resources are not anticipated for development Alternatives 1A, 2A, and 3A because they are “No Action” alternatives. Alternative 1B (TW Extension) may have impacts to general vegetation and wildlife through the construction of the parallel taxiway and the permanent loss of grassland habitat. General plant and wildlife species (i.e. ground-nesting mammals, and birds) may be displaced with the implementation of Alternative 1B. Impacts resulting from this alternative are determined to be moderate. Alternatives 2B (RW Lighting Rehab.) and 3B (AWOS Land) involve construction of lighting improvements, or the acquisition of land for a weather station that has a very small footprint that is expected to have an insignificant impact on biotic resources. Therefore, impacts resulting from these alternatives are determined to be insignificant for general plant species and wildlife. There are no open bodies of water on the airport, or in the immediate vicinity. 4.2.1 General Vegetation The on-site investigation at the Afton – Lincoln County Airport revealed the presence of one general vegetative community classified as rangeland/grassland. Common species observed in the rangeland/grassland community included crested wheatgrass (Agropyron cristatum), redroot pigweed (Amaranthus retroflexus), cheatgrass (Bromus tectorum), slender wheatgrass (Elymus trachycaulus), foxtail barley (Hordeum jubatum), smooth brome (Bromus inermus), western salsify (Tragopogon dubius), tufted hairgrass (Deschampsia cespitosa), yarrow (Achillea millefolium), alfalfa (Medicago sativa), wild oat (Avena fatua), field timothy (Phleum pretense), field pennycress (Thlaspi arvense), common toadflax (Linaria vulgaris), and white campion (Silene alba). 4.2.1.1 Impacts Alternatives 1A, 2A, and 3A: No impacts to general vegetation will occur with the “No Action” alternatives. Therefore, there are no mitigation measures required for these alternatives. Alternative 1B (TW Extension): Permanent loss of vegetation will occur where the taxiway is extended and associated improvements are constructed within the project area. However, the amount of vegetation lost will be minimal and project activities are expected to have minimal effects to general vegetation communities in the area. Alternative 2B (RW Lighting Rehab.): Temporary loss of vegetation will occur with the installation of lighting circuit improvements. The amount of vegetation lost will be minimal and vegetation is likely to naturally reestablish itself after installation activities are complete.


Alternative 3B (AWOS Land): No impact to general vegetation is anticipated to occur with acquiring approximately 65 acres of property adjacent to the airport for the relocation of the AWOS III. 4.2.1.2 Mitigation Measures Alternatives 1B (TW Extension) and 2B (RW Lighting Rehab.): Revegetate bare ground that is created from construction activities with a desirable seed mix that is appropriate for the area and that will provide competition against invasive species’ establishment and spread. 4.2.2 Plant Species of Concern The 2012 Wyoming Plan Species of Concern list is maintained by the Wyoming Natural Diversity Database (WYNDD) and contains vascular plant species considered to be of greatest conservation concern in the state. This list was reviewed and Table 4-2 contains the plant species of concern that occur in Lincoln County, Wyoming, heritage ranking, habitat and potential to occur within the project area. Heritage ranking is denoted by a letter: G: Global rank assignment, S: Subnational (state/jurisdictional) assigned by WYNDD biologists, or T: Trinomial rank. The letters are followed by numbers 1 through 5, with 1 being critically imperiled and 5 being secure (Heidel 2012).

Table 4-2: Plant Species of Concern in Lincoln County, Wyoming

Species Name Heritage Rank

Habitat Habitat Specifications Within Project Area?

Swallen mountain ricegrass (Oryzopsis swallenii)

G3G4/S2 Open, rocky sites, frequently with low sagebrush.

No

Douglas-fir dwarf-mistletoe (Arceuthobium douglasii)

G5/S1 Established Douglas fir stands

No

Sodaville milkvetch (Astragalus lentiginosus)

G5T5/S1 Plains and hills Yes

Payson’s milkvetch (Astragalus paysonii)

G3/S2 Openings/gaps in mixed grand fir and Douglas fir forests

No

Trelease’s racemose milkvetch (Astragalus racemosus)

G5T2/S2 Badlands, outwashes, and slopes along major river

No




valleys, on sparsely vegetated habitat.

Bolander’s sedge (Carex infirminervia)

G5/S2 Forests, slopes above streams, grassy slopes

No

Utah mountain lilac (Ceanothus martinii)

G4/S1 Dry areas alongside yellow pine, juniper, sagebrush and oak pine.

No

Barneby’s thistle (Cirsium barneby)

G3G4/S1 Unknown Unknown

Large-flower collomia (Collomia grandiflora)

G5/SH Dry open or lightly wooded places.

Yes

Western dodder (Cuscuta occidentalis)

G4G5/S1

Mountain big sagebrush communities above 6400 feet

No

Boreal draba (Draba borealis)

G4/S2 Moss-rich limestone cliff habitat

No

Rockcress draba (Draba globosa)

G3/S3 Moist, gravelly alpine meadows, slopes, summits, swales, talus, and tundra, often on limestone derived soils at elevations of 8,100 to 12,400 feet.

No

Payson’s draba (Draba paysonii)

G5T3/S2 Rocky places on hardpan clay and sand. Wyoming populations between 10,000 and 12,600 feet.

No

Winward’s narrowleaf goldenweed (Ericameria discoidea)

G4G5/S1 Dry, open, rocky outcrops

Yes

Divergent wild buckwheat

G4G5/S1 Barren or semi-barren clay,

No




(Eriogonum divaricatum)

shale, or sandstone slopes in cushion plant-bunchgrass communities or on the fringes of sagebrush communities.

Milk Kelloggia (Kelloggia galioides)

G5/S1 Open slopes No

Entire-leaved peppergrass (Lepidium integrifolium)

G2G3/S1 Sparsely vegetated and seasonally wet silt flats at 6,170 to 6,790 feet.

No

Large fruited bladderpod (Lesquerella macrocarpa)

G2/S2 Sparsely vegetated areas or unvegetated margins. Not found in areas of high cover grasses.

No

Western bladderpod (Lesquerella multiceps)

G3/S1 Sparsely vegetated areas

No

Prostrate bladderpod (Lesquerella prostrate)

G2G3/S2 Slopes and rims on clays or sandstones at elevations of 6,630-7,700 feet.

No

Ternate desert-parsley (Lomotium triternatum)

G5T4T5/S1 Prairie grasslands, eroded slopes, glades, and rocky open ground.

Yes

Mountain wildmint (Monardella odoratissima)

G4G5T3T5/S1

Mountainous areas and sagebrush scrub

No

Desert glandular phacelia (Phacelia glandulosa)

G4T2Q/S1 Cushion plant and bunch grass communities on sparsely vegetated slopes

No




Nelson phacelia (Phacelia salina)

G3Q/S2 Alkaline flats and clay slopes.

No

White-margined phlox (Phlox albomarginata)

G4/S1 Plains, hilly piedmont, and mountains at low to middle elevations, upper slopes of rolling to dissected terrain, escarpments and rock ledges

No

Dorn’s twinpod (Physaria dornii)

G1/S1 Open gravelly slopes, edge of thickets with partial shade.

No

Douglas’ campion (Silene douglasii)

G4/S1 Dry areas in the plains or open slopes.

Yes

Large flower triteleia (Triteleia grandiflora)

G4G5/S2 Grassy areas among sagebrush and pine forests

No

None of the species identified on the list of plant species of concern in Lincoln County, Wyoming have been previously identified within the project site (according to database searches and agency correspondence) and were not identified during the on-site investigation. However, habitat specifications (i.e., prairie/rangeland communities and plains) for several of the species do exist within the project area. Given the disturbed nature of the project area and that none of the plant species of concern were identified on the property during the on-site investigation, it is not likely that the proposed project will have any impact on the listed plant species of concern. 4.2.2.1 Impacts Alternative 1A, 2A, and 3A: No impacts to plant species of concern will occur with the “No Action” alternatives. Therefore, there are no mitigation measures required for these alternatives. Alternative 1B (TW Extension), 2B (RW Lighting Rehab.) and 3B (AWOS Land): Based on the results of the field investigation and the absence of plant species of concern, no adverse impacts to plant species of concern are anticipated from construction activities associated with Alternatives 1B, 2B or 3B. Therefore, there are no mitigation measures required for Alternatives 1B, 2B or 3B.


4.2.3 Noxious Weeds Noxious weeds are defined by the Wyoming Weed and Pest Council (WWPC) (W.S. 11-5.102 (xi)), as the weeds, seeds or other plants that are considered detrimental, destructive, injurious or poisonous, either by virtue of their direct effect or as carriers of diseases or parasites that exist within this state (Wyoming) and are on the designated list (WWPC 2010). A list of Wyoming designated noxious weeds is found below.

Wyoming Designated Noxious Weeds Field bindweed (Convolvulus arvensis) Canada thistle (Cirsium arvense) Leafy spurge (Euphorbia esula) Perennial sowthistle (Sonchus arvensis) Quackgrass (Agropyron repens) Hoary cress (Cardaria draba) Perennial pepperweed (Lepidium latifolium) Ox-eye daisy (Chrysanthemum leucanthemum) Skeletonleaf bursage (Franseria discolor) Russian knapweed (Centaurea repens) Yellow toadflax (Linaria vulgaris) Dalmatian toadflax (Linaria dalmatica) Scotch thistle (Onopordum acanthium) Musk thistle (Carduus nutans) Common burdock (Arctium minus) Plumeless thistle (Carduus acanthoides) Dyers woad (Isatis tinctoria) Houndstounge (Cynoglossum officinale) Spotted knapweed (Centaurea maculosa) Diffuse knapweed (Centaurea diffusa) Purple loosestrife (Lythrum salicaria) Saltcedar (Tamarix spp.) Common St. Johnswort (Hypericum perforatum) Common Tansy (Tanacetum vulgare) Russian olive (Elaeagnus angustifolia)

Musk thistle was the only Wyoming-designated noxious weed identified within the project area. Minimal populations of musk thistle were identified in scattered, low-density infestations throughout the project area. 4.2.3.1 Impacts Construction-related disturbance could promote noxious weed invasion and spread. The primary concern regarding disturbance to vegetation should focus on the potential of invasive weed establishment and spread. Bare ground created from disturbance


facilitates favorable conditions for weeds to spread into those disturbed areas and for viable weed seeds in the seed bank to become established. Alternative 1A, 2A, and 3A: The “No Action” alternatives will not promote the spread of noxious weeds and invasive species as no construction activities will take place. Therefore, there are no mitigation measures required for these alternatives. Alternatives 1B (TW Extension) and 2B (RW Lighting Rehab.): In areas where the ground is disturbed as a result of construction activities, the spread of noxious weeds and invasive species is possible. Alternative 3B (AWOS Land): Acquiring land for AWOS relocation will not promote the spread of noxious weeds and invasive species as no ground-disturbing activities will take place. Therefore, no mitigation measures will be required for this alternative. 4.2.3.2 Mitigation Measures Potential impacts from noxious weeds are expected to be minor and short-term. In order to prevent long-term noxious weed impacts and unnecessary harm to desirable project area resources, the following mitigation measures are recommended. Alternatives 1B (TW Extension) and 2B (RW Lighting Rehab.): Before the proposed construction activities are implemented, a weed management plan should be developed in coordination with the Wyoming Weed and Pest Council agent and Lincoln County Weed and Pest District to identify weed control strategies within the proposed project area. At a minimum, equipment will be thoroughly cleaned prior to mobilization to the site. To reduce the spread and establishment of noxious weeds and to re-establish permanent vegetation, seed mixes appropriate for the area should be utilized to reseed areas disturbed by construction activities. Implementation of these mitigation measures shall prevent adverse effects from noxious weeds. 4.2.4 General Wildlife A reconnaissance-level on-site evaluation was completed to examine and accurately assess the project area for the presence or absence of wildlife species occupying the project area. The analysis included an evaluation of the potential impacts associated with proposed project activities on mammals, amphibians, reptiles, and birds inhabiting the site. The September 12, 2011 field investigation confirmed that the on-site habitat conditions for generalist wildlife species are not of high quality due to its existing disturbed characteristics (transportation infrastructure associated with the airport) and its adjacency to Wyoming State Highway 89, concerted agricultural areas, and existing residences. In addition, the project area and the immediate surrounding vicinity are not indicative of pristine, unique, or remote wildlife habitat conditions due to the presence of residential areas and a heavy volume traffic corridor within close proximity of the project


area. On-site habitat conditions adjacent to the airport infrastructure consist of rangeland and irrigated pasture. In addition, a wildlife barrier fence currently surrounds the airport to prevent large mammals (i.e., deer and antelope) from accessing airport property. Wildlife or signs of wildlife (tracks, scat, etc) were not observed on the airport property. Two mule deer (Odocoileus hemionus) were observed on the property adjacent to the airport, on the other side of the wildlife fence. Various birds including sparrows, meadowlark, and a kestrel were observed within the airport boundary. Various songbirds and raptors may utilize habitat within and adjacent to the project site. Communication with John Emmerich, Deputy Director for the Wyoming Game and Fish Department concluded that there are no terrestrial wildlife or aquatic habitat concerns pertaining to proposed project activities. Correspondence records can be found in Appendix II. 4.2.4.1 Impacts Alternatives 1A, 2A, and 3A: No impacts to general wildlife will occur with this “No Action” alternative as no construction activities will take place. Therefore, no mitigation measures are required for these alternatives. Alternative 1B (TW Extension): The implementation of project activities will result in the permanent loss of areas of upland vegetation where the construction activities take place. However, these areas are not currently characterized as quality wildlife habitat due to disturbance levels from airport activities and previous displacement of wildlife species. Areas of adjacent suitable habitat exist that can support species that are potentially displaced by construction activities. Therefore, it is anticipated that the implementation of Alternative 1B will have minimal adverse effects to general wildlife species. Alternative 2B (RW Lighting Rehab.): No impacts to general wildlife will occur with Alternative 2 as the only disturbance that would occur is updating the current lighting system. Therefore, no mitigation measures are required for Alternative 2B. Alternative 3B (AWOS Land): The acquisition of land for AWOS relocation will not result in the loss of any general wildlife habitat. Therefore, it is anticipated that the implementation of Alternative 3B will have minimal adverse effects to general wildlife species. 4.2.5 Wildlife Species of Concern According to a search of the Wyoming Natural Diversity Database, no wildlife species of concern have been previously identified within or in the immediate vicinity of the airport property. In addition, communication with the Wyoming Game and Fish Department concluded that there are no terrestrial wildlife or aquatic habitat concerns (including


species of concern) in or around the airport property (Appendix II). Federally-listed threatened and endangered (T&E), candidate or proposed species are addressed in Section 4.8 of this document. 4.2.5.1 Impacts Alternatives 1A, 2A, and 3A: No impacts to wildlife species of concern will occur with this “No Action” alternative as no construction activities will take place. Therefore, no mitigation measures are required for this alternative. Alternatives 1B (TW Extension), 2B (RW Lighting Rehab.) and 3B (AWOS Land): Based on the information obtained from the on-site visit and communication with Wyoming Game and Fish Department staff, there are no wildlife species of concern within the project area. No adverse impacts to wildlife species of concern are anticipated from construction associated with Alternative 1B or 2B and the acquisition of land associated with Alternative 3B described in this Environmental Assessment. Therefore, there are no mitigation measures required for Alternatives 1B, 2B, and 3B. 4.2.6 General Fisheries No surface water bodies are present on the airport property. Therefore, the airport property does not support fish populations. No impacts to fish species are anticipated to result from project activities. 4.2.6.1 Impacts Alternatives 1A, 1B, 2A, 2B, 3A and 3B: There are no perennial surface waters present on the airport property, or in the immediate vicinity. Therefore, there are no impacts to general fisheries or mitigation measures required for any of the alternatives. 4.2.7 Fish Species of Concern As previously stated, there are no perennial surface waters present on the airport property, or in the immediate vicinity of the project area to support fish species (including fish species of concern). 4.2.7.1 Impacts Alternatives 1A, 1B, 2A, 2B, 3A and 3B: There are no perennial surface waters present on the airport property, or in the immediate vicinity. Therefore, there are no impacts to fish species of concern or mitigation measures required for any of the alternatives.


4.3 COASTAL BARRIERS The proposed project is not located within the Coastal Barrier Resources System, as delineated by the U.S. Fish and Wildlife Service (USFWS) or Federal Emergency Management Agency (FEMA) coastal barrier maps. No impacts relating to coastal barriers are anticipated from airport development for any of the proposed development alternatives. 4.4 COASTAL ZONE MANAGEMENT The proposed project would not affect a coastal zone as defined by an applicable Coastal Zone Management Plan (CZMP). There are no coastal zones in the vicinity of the property. No impacts relating to coastal zone management are anticipated from airport development for any of the proposed development alternatives. 4.5 COMPATIBLE LAND USE FAA Order 1050.1E, Environmental Impacts: Policies and Procedures notes that the compatibility of existing and planned land uses in the vicinity of an airport is usually associated with the extent of the airport’s noise impacts. Therefore, there must be assurances that zoning laws, existing infrastructure, and adoption of zoning regulations are compatible with the location of the Airport and forecast noise contours. See Section 1.5.17 ‘Noise’ for additional information on the assessment of noise. Development of the Afton – Lincoln County Airport is consistent with the Town of Afton regulations for the area of the airport as identified in Lincoln County Land Use Regulations - APPENDIX B – Airport Overlay. This document can be referenced in Appendix VI of this document. Development Alternatives 1A, 2A, and 3A are not anticipated to result in impacts to compatible land use as they are “No Action” alternatives. Development Alternatives 1B (TW Extension) and 2B (RW Lighting Rehab.) are not anticipated to result in impacts to compatible land use as the projects are proposed to be constructed within the boundaries of the airport. While construction of the parallel taxiway will result in aircraft taxiing in closer proximity to the Afton Airpark residences, the nature of the development is such that aircraft noise is compatible. Development Alternative 3B (AWOS Land) would expand the boundaries of the airport such that the relocation of the AWOS would then occur within the boundaries of the airport. The projected AWOS relocation would involve a small footprint for tower foundations and associated sensor equipment. The intent would not be to enclose the entire property acquired in fencing, but instead fence only the immediate area around the AWOS. This would allow the remainder of the proposed property (approximately 64.5+ acres of the approximate 65 acres) to remain as it presently exists, as pasture ground.


4.6 CONSTRUCTION Alternatives 1A, 2A, and 3A are not anticipated to have any impacts as they are “No Action” alternatives. Construction of Alternative 1B (TW Extension) and 2B (RW Lighting Rehab.) improvements are anticipated to moderately affect 1) air quality, 2) biotic resources, and 3) noise, and induced socioeconomic impacts for Alternative 2B (RW Lighting Rehab.) exclusively. Refer to those specific resource categories for additional information. Construction of Alternative 1B (TW Extension) will entail excavation and import of base material and paving. Construction of Alternative 2B (RW Lighting Rehab.) will entail excavation. Both tracked and wheeled vehicles will likely be used. Reference to FAA AC 150/5370-10F, Standards for Specifying Construction of Airports will be incorporated in the project specifications to provide an additional source of information to reduce airport related construction impacts. 4.6.1 Impacts Construction activities could cause specific environmental temporary impacts that are adverse in nature, but localized to the project site. These temporary impacts and their degree of adversity would be reduced as construction activities are completed. The following moderate impacts are anticipated during the construction of the Alternative 1B (TW Extension) and 2B (RW Lighting Rehab.) improvements:

Temporary increases in noise levels due to the operation of construction equipment.

Temporary and minor impacts to air quality due to vehicle emissions from

construction equipment and particulate generation (dust) from the construction operations.

Potential for surface water contamination from construction activities. There is no construction associated with the acquisition of the 65 acres of land. Relocation of the AWOS at a future date is projected to result in insignificant impacts. 4.6.2 Mitigation The following mitigation is proposed for those impacts listed above:

Impacts from construction noise will be limited to daylight hours in an effort to be compatible with residences of the Afton Airpark development (see Section 4.17 - Noise). Construction operations are proposed to be largely completed during day time hours.

Vehicle emissions are to be in compliance with EPA standards and dust control

will be required of the contractor throughout the project (water, calcium chloride, etc.)


A National Pollutant Discharge Elimination System (NPDES) permit including

approval of a Stormwater Pollution Prevention Plan (SWPPP) will be likely required from the Wyoming Department of Environmental Quality. Surface waters will be protected by implementing Best Management Practices (BMP) and installing silt fencing, earthen dams, and erosion control measures to prevent contamination from either construction equipment fuels and oils or erosion from disturbed areas. While there are no surface waters in the immediate vicinity of the airport, consideration will be given to BMP’s as necessary.

4.7 SECTION 4(f) LAND Section 4(f) of the Department of Transportation (DOT) Act prohibits the use of specific types of publicly owned lands, provided there is no feasible and prudent alternative, and that use of such lands is mitigated as necessary to reduce any impacts. Such publicly owned lands can include public parks or recreational areas, wildlife or waterfowl refuges of national, State, or local significance, and land from a historic site of national, state, or local significance as determined by the officials having jurisdiction thereof. No impacts relating to Section 4(f) land are anticipated from airport development for any of the proposed development alternatives. There are no identified Section 4(f) lands associated with, or in the immediate vicinity of the project. The nearest identified 4(f) land is the Bridger National Forest (approximately 1.5 miles east) and Caribou - Targhee National Forest (approximately 8.5 miles west), as can be seen in Figure 1-1. Based on discussions with Town of Afton staff, there are no known 4(f) lands in the Town of Afton, located immediately to the northeast of the airport. The airport occupies the extreme southwest corner of the Afton city limits. As described in Chapter 1 Purpose and Need, the general purpose of the various projects is to improve safety and operational readiness. The proposed improvements will not in themselves change the traffic volume or fleet mix of the airport. The Wyoming State Historic Preservation Office, the U.S. Department of Agriculture (USDA) Forest Service Offices for the Bridger National Forest and Targhee National Forest, U.S. Department of Interior – Bureau of Land Management (BLM), Lincoln County and the Town of Afton were provided drafts of this document for preliminary review and comment. The BLM and Wyoming State Historic Preservation Office provided written responses indicating no concerns (Appendix II). No other comments were received as of the time of this writing. 4.8 FEDERALLY LISTED ENDANGERED AND THREATENED

SPECIES 4.8.1 Project Area Description Afton is located approximately 1.5-miles west of the Bridger-Teton National Forest and approximately 8 miles from the Wyoming/Idaho border. The property immediately surrounding the airport is used primarily for agricultural purposes with scattered rural


residential developments. The east side of the airport borders commercial businesses, agriculture, and the Afton Airpark – a residential aviation development. The Afton Airport’s elevation is 6,221 feet MSL with the mean maximum temperature of the warmest month of 82°F. The airport has a total area of approximately 273.7 acres, all of which are owned in fee by the Afton – Lincoln County Airport Joint Powers Board. The perimeter of the airport property is surrounded by a combination of 8’ high tensile mesh fence with an additional 1’ of barbwire (3 strands) and 7’ chain link fence with an additional 1’ of barbwire (3 strands) that serves as a wildlife barrier for large mammals (i.e. deer and antelope). The project area and the immediate surrounding vicinity are not indicative of pristine, unique, or remote wildlife habitat conditions due to the presence of the airport and associated infrastructure, converted agricultural areas, and a heavy volume traffic corridor (Hwy 89) within close proximity of the project area. 4.8.2 Methodology To confirm the presence or absence of any protected species in or within the vicinity of the project area, a preliminary request for information on T&E species potentially affected by this project was requested of and received from U.S. Fish and Wildlife Service (USFWS) biologists. The USFWS response letter is provided in Appendix II. Additionally, a reconnaissance-level on-site evaluation of the project area was performed to examine and accurately assess the property for the presence or absence of T&E species, candidate species, proposed species, and their habitat. The analysis included an evaluation of the potential impacts to biological resources from proposed project development activities. An off-site literature review was also completed to gather information concerning T&E species, candidate species, proposed species, and their habitat. The literature review consisted of an internet search to gather species information. Sites such as the USFWS Wyoming Ecological Services website were consulted (USFWS 2012). Table 4-3 states the current status and habitat specification for the T&E species identified as potentially occurring in Lincoln County, Wyoming.


Table 4-3. Potential T&E, Candidate, and Proposed Species Present in Lincoln County Wyoming; Species Status; Habitat

4.8.3 Results A preliminary request for information on T&E species potentially affected by this project was sent to USFWS and is provided in Appendix II. A letter dated November 6, 2012 was received from USFWS that stated that based on the information provided, it is unlikely that the proposed work will adversely affect any T&E species or migratory birds and that the proposed project is in compliance with the Endangered Species Act of 1973, 16 U.S.C. 1531 et seq. and the Migratory Bird Treaty Act, 16 U.S.C. 703. Black-Footed Ferret Habitat specifications for the black-footed ferret (identified as prairie dog towns) are not located on or adjacent to the airport property. Additionally, correspondence with the USFWS indicated that adverse impacts to T&E species are not likely given the scope of the proposed project. Therefore, it was determined that the proposed airport projects will have “no effect” on the federally-endangered black-footed ferret.

Species

Status Habitat

Black-footed ferret (Mustela nigripes)

Endangered Prairie dog towns

Canada lynx (Lynx canadensis)

Threatened Montane forests

Greater sage grouse (Centrocercus urophasianus)

Candidate Sagebrush communities

Grizzly bear (Ursus arctos horribilis)

Threatened Montane forests

Ute ladies’ tresses (Spiranthes diluvialis)

Threatened Seasonally moist soils and wet meadows of drainages below 7,000 feet elevation

Whitebark pine (Pinus albus)

Candidate Montane forests

Wolverine (Gulo gulo)

Candidate Montane forests

Yellow-billed Cuckoo (Coccyzus americanus)

Candidate Large tracts of woody riparian vegetation.


Canada Lynx Habitat specifications for the Canada lynx (identified as large tracts of undisturbed montane forests) are not located on or adjacent to the airport property. Additionally, correspondence with the USFWS indicated that adverse impacts to T&E species are not likely given the scope of the proposed project. Therefore, it was determined that the proposed airport project will have “no effect” on the federally-threatened Canada lynx. Greater Sage-Grouse Habitat specifications for greater sage-grouse (identified as sagebrush habitats) are not located within or adjacent to the airport property. Additionally, correspondence with USFWS indicated that adverse impacts to T&E species are not likely given the scope of the proposed project. Therefore, it was determined that the proposed airport projects will “not jeopardize the continued existence of” the candidate species greater sage grouse. Grizzly Bear Habitat specifications for the grizzly bear (identified as montane forests) are not located within or adjacent to the airport property. Additionally, correspondence with the USFWS indicated that adverse impacts to T&E species are not likely given the scope of the proposed project. Therefore it was determined that the proposed airport projects will have “No Effect” on the federally-threatened species grizzly bear. Ute Ladies’ Tresses Potential habitat specifications for Ute ladies’ tresses (old river meanders and wetland edges) are not located within or adjacent to the airport property. Additionally, correspondence with the USFWS indicated that adverse impacts to the T&E species are not likely given the scope of the proposed project. Therefore, it was determined that the proposed airport projects will have “No Effect” on the federally-threatened Ute ladies’ tresses. Whitebark Pine Potential habitat specifications for whitebark pine (sub-alpine environments) are not located within or directly adjacent to the airport property. Additionally, correspondence with the USFWS indicated that adverse impacts to the T&E species are not likely given the scope of the proposed project. Therefore, it was determined that the proposed airport projects will “not jeopardize the continued existence of” the candidate species whitebark pine.


Wolverine Potential habitat specifications for wolverine (montane forests) are not located within or directly adjacent to the airport property. Additionally, correspondence with the USFWS indicated that adverse impacts to the T&E species are not likely given the scope of the proposed project. Therefore, it was determined that the proposed airport projects will “not jeopardize the continued existence of” the candidate species wolverine. Yellow-Billed Cuckoo Potential habitat specifications for the yellow-billed cuckoo (wooded riparian areas) are not located within or directly adjacent to the airport property. Additionally, correspondence with the USFWS indicated that adverse impacts to the T&E species are not likely given the scope of the proposed projects. Therefore, it was determined that the proposed airport projects will “not jeopardize the continued existence of” the candidate species yellow-billed cuckoo. 4.8.4 Mitigation Alternative 1A, 2A, and 3A: No impacts to T&E, proposed, or candidate species will occur with this “No Action” alternative as no construction activities will take place. Therefore, no mitigation measures are required for these alternatives. Alternative 1B (TW Extension), 2B (RW Lighting Rehab.), and 3B (AWOS Land): No impacts to T&E, proposed, or candidate species will occur with Alternative 1B, 2B, or 3B as project activities will take place on property that does not provide necessary habitat specifications. Therefore, no mitigation measures are required for these alternatives. 4.9 ENERGY SUPPLIES, NATURAL RESOURCES, AND

SUSTAINABLE DESIGN Energy requirements associated with airport improvements generally consist of either: 1) those related to existing facilities (terminal and airfield lighting requirements), or 2) air/ground vehicle movement requiring fuel consumption. Alternatives 1A, 2A, and 3A are not anticipated to have any impacts as they are “No Action” alternatives. The proposed parallel taxiway extension (Alternative 1B) would result in the installation of medium intensity taxiway lighting (MITL) for the full parallel taxiway system. Alternative 2B (RW Lighting Rehab.) would involve the replacement of aged fixtures and wiring. There are no new lights or signs proposed to the runway lighting circuit. 4.9.1 Impacts Impacts resulting from the implementation of development Alternatives 1B (TW Extension) and 2B (RW Lighting Rehab.) are anticipated to be insignificant to moderate as no energy short falls and small increases in impacts on energy availability may


occur. The following impacts are anticipated during the construction of the Alternative 1B (TW Extension) and 2B (RW Lighting Rehab.) improvements:

Increased load on the overall existing utilities for the new taxiway circuit.

Replacement of the existing infrastructure for the runway lighting rehabilitation may reduce the overall load due to improved conductivity and improvements in fixture efficiency.

Acquisition of the proposed 65 acres of land through fee title or easement(s) will not in and of itself result in any effect on energy supplies, natural resources, and sustainable design. When the AWOS is relocated at a future date, the existing power supply will also be relocated so there would be no additional power requirements on the system. In addition, there should be no increased consumption from air or ground vehicles that should produce shortages in supplies. No impacts are anticipated to mineral resources beyond the import of base materials and asphalt for paving of the parallel taxiway. Quantities are projected to be insignificant in regards to local supplies available. 4.9.2 Mitigation The following mitigation is proposed for those impacts listed above:

Fixture types (LED and quartz) will be reviewed for cost-benefit impacts during the design process of the parallel taxiway extension.

Replacement of the existing infrastructure for the runway lighting rehabilitation may reduce the overall load due to improved conductivity and improvements in fixture efficiency. The cost-benefit analysis will also include the evaluation of LED versus quartz fixtures to ascertain the impacts.

While the relocation of the AWOS equipment itself is not being assessed at this time, an estimate of the impacts can be made. Some components of the system may be upgraded so as to reduce the overall draw on the system. In the event that additional upgrades are installed in the future, it is estimated that the low voltage utility draw would be negligible to the system as a whole. 4.10 ENVIRONMENTAL JUSTICE No impacts relating to environmental justice are anticipated from airport development for any of the proposed alternatives. The Council on Environmental Quality (CEQ) define a low income population as “any readily identifiable group of low-income persons who live in geographic proximity, and, if circumstances warrant, geographically dispersed/transient persons (such as migrant workers or Native Americans) who will be similarly affected by a proposed program,


policy, or activity.” The CEQ also defines a minority population as “one that exceeds 50 percent of an affected area, or the population percentage is meaningfully greater than the minority population percentage in the general population or other appropriate geographic analysis.” Analysis of U.S. Census Bureau information, as well as County and Town information, does not indicate the presence of either low-income populations or minority populations residing in the immediate area of the airport. Given that there are no identified populations, and that there are no identified actions that would cause disproportionately high and adverse effects on minority or low income populations if they did exist, it is determined that implementation of the proposed action would have no effect on low income or minority populations. 4.11 FARMLANDS The Farmland Protection Policy Act (FPPA) regulates Federal actions with the potential to convert farmland to non-agricultural use. Farmland is defined as “prime or unique” as referenced in the FPPA, or as determined by the appropriate state or local government to be of importance. The FPPA defines prime farmland as that that has the best combination of physical and chemical characteristics for producing food, feed, forage, fiber and oilseed crops, and is also available for these uses. Unique farmland is that that is used for production of specific high-value food and fiber crops; it has the special combination of soil quality, location, growing season, and moisture supply needed to economically produce sustained high quality or high yields of specific crops. The State of Wyoming has limited prime or unique farmland designated according to the Natural Resource Conservation Service (NRCS). Preliminary review reflects no known prime and unique farmland in the vicinity of Afton, Wyoming. NRCS web soil survey information is provided in Appendix X for the general vicinity of the airport for further information. While the proposed 65 acres of land acquisition involves irrigated pasture ground, this area is not identified as prime or unique farmland. The intent with the AWOS relocation is to fence the immediate area of the AWOS (approximately 0.1 acres) with the remainder to continue to serve as pasture ground. No impacts relating to farmlands are anticipated from airport development for any of the proposed development alternatives. 4.12 FLOODPLAINS Executive Order 11988, Floodplain Management, contains the requirements to evaluate floodplains and flood risk. The Federal Emergency Management Agency (FEMA) issues Flood Insurance Rate maps that identify flood risk. According to FEMA flood hazard map 56023C0655D, dated November 16, 2011 (Appendix XI), the project area is designated as Zone X, outside the 100-year flood zone established by FEMA. Zone X is defined as an area of moderate flood hazard, usually the area between the limits of the 100-year and 500-year floods. No impacts relating to the floodplain are anticipated from airport development for any of the proposed development alternatives.


4.13 HAZARDOUS MATERIALS Information pertaining to hazardous material sites was reviewed from the EPA’s Comprehensive Environmental Response, Compensation, and Liability Information System (CERCLIS) database. There were no identified sites or issues pertaining to hazardous wastes, substances, or materials in the vicinity of the airport. Two sites were identified in other areas of Lincoln County. The Cokeville Meadows National Wildlife Refuge, approximately 50 miles to the south, and R.J. Refinery in Labarge, Wyoming, approximately 45 miles to the southeast. Additional sites were also noted in Conda and Soda Springs, Idaho, approximately 35 miles to the west. No impacts relating to hazardous materials are anticipated from airport development for any of the proposed development alternatives. There have been no sites or issues identified by local authorities, or noted during the reconnaissance-level pedestrian survey conducted for the environmental review of biotic resources, wetland inventory, or cultural resource inventory. While an Environmental Due Diligence Audit (EDDA) has not been conducted, the existing land use indicates that it is not, and does not have the immediate potential for hazardous wastes, substances, or materials. The Wyoming Department of Environmental Quality – Solid and Hazardous Waste Division was contacted (Appendix II) regarding the proposed alternatives and has not provided any indication of hazardous material issues in the area. 4.14 HISTORICAL AND ARCHAEOLOGICAL There are a number of Federal statutes and Executive Orders that guide protecting historic and cultural resources. The national Historic Preservation Act defines Federal agency’s responsibilities for the protection of sites listed or eligible for listing in the National Register of Historic Places. It also establishes the requirements for consultation with the State Historic Preservation Office and/or Tribal Historic Preservation Officers if there is a potential for adverse effects on listed or eligible sites. A cultural resource inventory has been conducted with this environmental assessment for the parallel taxiway extension and proposed 65 acres of land to be acquired. This study is included in Appendix VII - Cultural Resources Inventory. The area reviewed encompassed all of the airport property within the existing animal control fence, as well as the proposed 65 acres of land. As a result of this inventory no previously recorded cultural properties were encountered and no new cultural properties were documented with the area of potential effects, or its immediate vicinity. An EA was also completed in May, 2004 for the runway extension project and improvements. That EA reflected that there were no known cultural or historic sites on, or in the immediate vicinity of the airport. The State Historical Preservation Office (SHPO) was contacted for initial public agency comment. The SHPO stated that it had no issues or comments regarding the proposed projects subject to the following stipulation: “If any cultural materials are discovered


during construction, work in the area shall halt immediately, the federal agency must be contacted, and the materials evaluated by an archaeologist or historian meeting the Secretary of the Interior’s Professional Qualification Standards…” (Appendix II). Given the area has been surveyed numerous times with no known previous impacts found, it is anticipated that there will be no impacts to cultural or historic properties under any of the project alternatives. 4.15 INDUCED SOCIOECONOMIC Socioeconomic impacts include extensive relocation of residents and community businesses, disruption of local traffic patterns, and the substantial loss in community tax base. If acquisition of real property or displacement of persons is a result of a project involving federal funding then certain policies are required to be followed. The proposed projects do not include property acquisition that encompasses residents or businesses, or involve the displacement of persons or businesses. Significant noise impacts are also not anticipated. None of the proposed projects change flight paths or approaches that might change the risk exposure to any associated areas of concern as well. While there are no alternatives that would require relocation of any housing or businesses, or negatively impact the community tax base, the construction of Alternative 2B (RW Lighting Rehab.) may require limited closure of the airfield to facilitate the installation of improvements. Closing of the runway will likely impact the Fixed Base Operator (FBO) and on airport repair facilities with respect to lost revenue for fuel, repairs, etc. Conceptual mitigation includes utilization of turf facilities by aircraft to access the FBO and other on-site facilities, coordinating with airport users to establish limited hours allowing air traffic to facilitate construction during daylight hours, establishing work hours for the contractor during nighttime hours when air traffic is not as frequent, and/or potential airport closure for several days during the week to facilitate extended work hours by the contractor. Air traffic may also be allowed to occur during construction with prior permission required in advance of arrival or departure. Construction operations may also be able to be conducted in conjunction with air traffic depending on the location of operations on the airfield. Coordination will be made with the Sponsor, FAA, WYDOT, and FBO/maintenance businesses during the preparation of the Construction Operations and Phasing Plan (COPP) to address potential safety measure/operational issues. Efforts will be made during design and construction to minimize the length of construction so as to reduce the overall impact on the airport users. 4.16 LIGHT EMISSIONS AND VISUAL EFFECTS For airports, light emissions of general concern can include ground-based lighting (runway/taxiway lighting, navigational aids, beacons, building/parking lot lighting, etc.), and aircraft lighting from approach lights. According to FAA Order 10501E, Change 1, Environmental Impacts: Policies and Procedures, due to relatively low levels of light


intensity from airport lighting, compared to background levels associated with airport development, light emission impacts are unlikely to have an adverse impact on human activity or the use or characteristics of protected properties. Visual effects are more subjective due that they include personal aesthetic preferences. These impacts can include contrasts between an area and its environment and the general perception of the community concerning any change. Usually visual effects at an airport that may provide potential significance include structures that may block scenic vistas, or significantly detract from the context of a site. No impacts relating to light emissions are anticipated from airport development for the proposed development Alternatives 1A, 2A, and 3A given there is no change in the lighting layout. Alternative 1B (TW Extension) will involve the installation of MITLs along the entire length of the parallel taxiway. These lighting improvements will consist of blue taxiway lights, with some minor signage improvements projected. Alternative 2B (RW Lighting Rehab.) will involve the replacement of existing aged runway light fixtures in their existing locations, and upgrades of the existing PAPIs from 2-box to 4-box. No additional lighting improvements are projected with the runway lighting rehabilitation. While Alternative 1B (TW Extension) constructs taxiway lighting closer to residences along the east boundary of the airport, the soft blue light is expected to be shielded by existing terrain and vegetation in numerous areas. The Afton Airport also has their lighting set up on radio control to time out after being activated for 15 minutes. This reduces utility bills and continual lighting impacts on neighbors which is expected to result in insignificant impacts overall. The residences in the general vicinity of the proposed taxiway lighting are those presently constructed in the Afton Airpark. The general development of the Airpark incorporates airport compatibility and acceptability to airport improvements. Alternative 3B (AWOS Land) with the acquisition of land will not directly result in any lighting emissions. Once the AWOS was relocated there would be a lighted beacon on the AWOS tower that may need to be evaluated for shielding from residences depending on the sighting circumstances. It is anticipated that the impacts of Alternatives 1B, 2B, and 3B are insignificant. 4.17 NOISE No impacts relating to noise are anticipated from airport development for the proposed development Alternatives 1A, 2A, and 3A given there is no change in the existing conditions. FAA Order 1050.1E states, "No noise analysis is needed for proposals involving Design Group I and II airplanes (wingspan less than 79 feet) in Approach Categories A through D (landing speed less than 166 knots) operating at airports whose forecast operations in the period covered by the EA do not exceed 90,000 annual propeller operations (247 average daily operations) or 700 jet operations (2 average daily operations).” FAA Order 5050.4B, Airports Environmental Handbook notes that the 700 jet operations can


be adjusted since the Cessna Citation 500, the Gates Learjet 35A, and any other jet aircraft producing equivalent or less levels of noise are quieter than many propeller aircraft under 12,500 pounds and therefore may be counted as propeller aircraft rather than jet aircraft. Afton currently experiences approximately 9,500 annual operations per year. While the volume and breakdown of jet aircraft into Afton is not available, the FBO has noted that jet traffic may exceed 700 operations. The FBO also noted that of those operations the most frequent user is a Cessna Citation 500 that falls under the adjustment criteria noted above as producing equivalent or less levels of noise then many propeller aircraft under 12,500 pounds. The Airport Master Record maintained by the FAA also notes that there are no jet aircraft based at Afton, further reducing the probability of jet operations. Given that the proposed projects do not promote an increase in jet traffic in and of themselves, that the proposed projects do not modify approaches/flight patterns, and that the Afton – Lincoln County Airport is not forecast to experience operations approaching FAA noise analysis thresholds (90,000 annual propeller operations) until well beyond the period covered by this assessment (FAA Terminal Area Forecast), a noise analysis is not being completed as a part of this Environmental Assessment. There are no noise-sensitive land uses, including schools or hospitals, within the immediate vicinity of the airport. While the construction of Alternative 1B (TW Extension) will result in the parallel taxiway being close to neighboring residential (Afton Airpark), the traffic is compatible with the general guidelines of the airpark development. The main exit taxiway from the Airpark to access the airport is also located such that it is between the Airpark residences and the airport property where the parallel taxiway is proposed – essentially any air traffic departing the Airpark taxis past existing Airpark residences enroute to the airside infrastructure. Taxiing aircraft are also in a powered down configuration as compared to increased power required for takeoff on the runway. This powered down configuration results in lower noise impacts than those associated with the aircraft at higher speeds. Construction of the parallel taxiway would result in increased noise from temporary construction activities. The plans and specifications for the project will address appropriate times of work so as to minimize impacts on the neighboring residences. Impact of the overall development of Alternative 1B (TW Extension) is expected to be moderate with respect to noise. Impacts for the proposed development Alternatives 2B (RW Lighting Rehab.) and 3B (AWOS Land) are projected to be insignificant in that the completed projects do not result in any increased noise. The only projected noise to be generated with these alternatives is limited construction operations which may include small vehicles and smaller mechanical equipment (trenchers, skid steers, small track hoes, etc.). 4.18 SECONDARY (INDUCED) IMPACTS Induced or secondary impacts are those that occur on other aspects of the community as a result of a development. Such impacts may include increases on transportation


infrastructure, water/sewer facilities, housing, employment, etc. Induced or secondary impacts beyond normal growth or development patterns should not occur from the airport development. Projected population increases are not a direct result of development at the airport. Public service demands and changes in business and economic activity will increase in time, but not beyond expected growth for the area. Development of the airport should have a positive overall impact on the surrounding communities in that indirect economic growth should be anticipated with any increased airport activity. No impacts relating to secondary (induced) impacts are anticipated from airport development for any of the proposed development alternatives.

4.19 SOCIAL IMPACTS No impacts relating to social impacts are anticipated from airport development for any of the proposed development alternatives. Development recommendations to meet the facility requirements of the Afton – Lincoln County Airport will not involve the need to relocate any residence, divide or disrupt established communities, disrupt orderly planned development, or create an appreciable change in employment. 4.20 SOLID WASTE The only alternative that is projected to have any impact on solid waste is Alternative 2B (RW Lighting Rehab.). Alternative 2B would result in the disposal or salvage of the existing PAPIs. The 2-box PAPIs can be salvaged for parts, given to another airport, or recycled. Alternative 2B would also result in the disposal or salvage of fixtures, transformers, and wiring. Fixtures can be salvaged for parts or recycled. Transformers and minor fixture parts can be disposed of in an authorized landfill. Conductor will likely be recycled for the copper, with the conductor insulation being disposed of. The overall solid waste impact is expected to be insignificant based on the volume of material and that none of the projects are a continual solid waste generator. No other impacts relating to solid waste are anticipated from any of the other development alternatives. 4.21 WATER QUALITY There are no surface water bodies on, or in the immediate vicinity of the airport. There was no groundwater noted in excavations as deep as 11 feet during the extension of the runway in 2005, and as deep as 8 feet during the digging of test holes in the proposed taxiway extension in 2011. No impacts relating to water quality are anticipated from airport development for any of the proposed development alternatives. 4.22 WETLANDS A wetland investigation was completed for the entire airport property within the animal control fence and for the proposed 65 acre parcel, and no aquatic resources were identified. No impacts relating to wetlands are anticipated from airport development for any of the proposed development alternatives. In addition, correspondence with the U.S. Army Corps of Engineers (USACE) program manager Matthew Bilodeau indicated


that USACE authorization would not be necessary for any of the project alternatives because they would not require any discharges of dredged or fill material into waters of the United States (see Appendix II for copies of correspondence). 4.23 WILD AND SCENIC RIVERS No impacts relating to wild and scenic rivers are anticipated from airport development for any of the proposed development alternatives. This impact category has been considered and is not applicable since no rivers classified as wild or scenic are currently listed, or proposed for listing, in the immediate vicinity of the airport. The nearest designated Wild and Scenic river is the Snake River, approximately 32 miles to the north near Alpine, Wyoming. The Salt River that flows within approximately 1.5 miles of the airport is a tributary of the Snake River. None of the proposed projects are projected to have any impacts on the Salt River, and hence the Snake River. The only other Wild and Scenic river system in the area is the Clarks Fork of the Yellowstone River, approximately 160 miles to the northeast from the project site. A map of the National Wild and Scenic Rivers System is in Appendix XII.

4.24 CUMULATIVE IMPACTS

A cumulative impact analysis provides officials with information on impacts resulting from other actions that have occurred or what will occur within a defined time and geographic area. The responsible authorities use this information to decide if a proposed airport project’s impact to a specific resource would cause a significant impact on that resource when added to past, present, and reasonably foreseeable actions within a specific geographic area or designated time frame. Cumulative effects may occur when the impacts of an airport action are considered with the actions of other agencies, tribes, private developers, or the FAA. The key question is: do the effects of the Airport’s (FAA) proposed action on a particular environmental resource, when added to the effects on the same resource due to Airport (FAA) and non-Airport actions, adversely impact that resource? Therefore, the cumulative analysis should focus on meaningful impacts, not inconsequential or irrelevant ones. Doing this allows the analysis to focus only on those environmental resources the proposed action would affect and the impacts it would cause. Upon review of the affected environment (airport property), there are no known past, present, or reasonably foreseeable actions that have been identified to date in the process of completing this Environmental Assessment that would result in cumulative impacts in association with the proposed action. Preliminary request for comment from public agencies have identified no other potential projects or environmental issues that may result in cumulative impacts. The proposed taxiway extension will disturb existing ground and remove a portion of that environment from use by biotic resources.

Documents

CHAPTER 4 AFFECTED ENVIRONMENT, ENVIRONMENTAL … · existing homes within the Afton Airpark, to within approximately 240 feet. The construction of the parallel taxiway extension