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C-1 A P P E N D I X C Case Study Narratives Case Study 1 General Aviation Airport Runway and apron rehabilitation, drainage improvements, and rotating beacon replacement Categorical Exclusion Project Description The interviews with FAA NEPA practitioners indicate that pavement rehabilitation is one of the most common projects reviewed at GA airports. Several of the FAA NEPA practitioners interviewed also emphasized the need for the project description to include all elements. The runway rehabilitation consisted of milling and overlaying distressed pavement including repairing and replacing the existing contraction joints, sealing cracks, and repainting the runway markings. In addition to these basic rehabilitation tasks, the project included modifying the surface grades to restore proper drainage flows. Correcting the drainage also required the addition of supplemental storm inlets to collect stormwater. For convenience in completing the NEPA process this CATEX also included the replacement of the Airportâs rotating beacon. That effort included decommissioning the existing off-Airport beacon and installing a new beacon on Airport property, which was collocated with the Airport's existing Automated Weather Observing System (AWOS). Key Environmental Issues Construction and/or operation of the project required the evaluation of potential air pollutant emissions from construction vehicles and equipment, and an analysis of the change in stormwater runoff resulting from the increase in impervious surfaces and the change in drainage flows at the Airport. This included an analysis of impacts that the increase in runoff would have on nearby floodplains. The Airport was determined not to have any archaeological resources, threatened or endangered species, or wetlands and these environmental resources would not be affected by the proposed project.
C-2 Guidance for Using the Interactive Tool for Understanding NEPA at General Aviation Airports Air Quality With regard to air quality, extraordinary circumstances that would preclude the use of a CATEX for NEPA compliance include not conforming to the State Implementation Plan (SIP) and/or exceeding any National Ambient Air Quality Standard (NAAQS). The project did not involve an airport capacity enhancement that would have operational effects; therefore, the air quality analysis was limited to construction emissions. General Conformity. Construction of the project would generate emissions from construction equipment. Construction activity involving earthwork is most likely to generate a substantial amount of emissions. The General Conformity Rule defines the methods for demonstrating that a project conforms to the SIP established for the region. The project was not specifically accounted for in the SIP, which is typical for airport projects, so other methods of demonstrating conformity were required. These other methods include preparing an applicability analysis (emissions inventory) to determine if project related emissions are less than the de minimis levels for the region and determining if the project type is listed as âpresumed to conformâ to the SIP. The airport is located in a marginal non- attainment area for ozone under the 8-hour standard based on the 2008 8-hour ozone classifications. This classification established the de minimis level and the intensity of development that qualifies under the presumed to conform list. The proposed development was consistent with the FAA's description of "routine maintenance and repair activities" and "routine installation and operation of airport navigation aids", which are presumed to conform with the SIP in accordance with the General Conformity Rule (72 Federal Register (FR) 145). The CATEX documented that the proposed development was presumed to conform and no further analysis was required. NAAQS. NAAQS are based on pollutant concentrations, which can only be positively determined through costly dispersion analyses. In practice, dispersion analyses are rarely if ever conducted for construction activity. The FAA agreed with the assumption that the project was presumed to conform and indicated that it was highly unlikely to exceed the NAAQS. No further analysis was required. Water Quality The project would entail temporary water quality impacts due to soil disturbing construction activities. The CATEX also had to consider the possibility that reconstruction would have increased the amount of impervious surface and stormwater runoff. Construction Impacts. As is typical, the Airport operates under a National Pollutant Discharge Elimination System (NPDES) general permit issued by the State. This general permit includes measures to ensure that discharges to surrounding surface waters would not violate water quality standards. The CATEX documented that, under this permit, the Airport sponsor and/or the selected contractor would be responsible for obtaining a construction permit including Best Management Practices to minimize the adverse effects of construction activity on water discharges.
Case Study Narratives C-3 Stormwater Management. As noted above, the Airport operates under a NPDES general permit, which would remain in effect. The CATEX documented that the project would not increase the amount of impervious surface or the associated volume of stormwater runoff and that, consequently, the Airportâs stormwater drainage system would continue to comply with the permit conditions. In addition, the CATEX documented that the new stormwater inlets around the apron included in the project would improve the drainage of the apron area during precipitation events by reducing ponding on the apron. NEPA Approach Initial consultation with the FAA Environmental Protection Specialist (EPS) indicated that both projects could be combined in a single documented CATEX in accordance with FAA Order 1050.1E. The following paragraph references have been updated to reflect the organization of FAA Order 1050.1F: 5-6.4.e for airfield paving, and 5-6.3.b for navigational aids. Combining two projects in one CATEX saved the airport time and expense in NEPA documentation processing. Thus, it is critical to determine whether more than one action could be included in a single CATEX.
C-4 Guidance for Using the Interactive Tool for Understanding NEPA at General Aviation Airports Case Study 2 Non-Hub Commercial Service (61 percent of operations by GA aircraft) Fixed Base Operator Hangar and Tie-Down Positions Categorical Exclusion Project Description The Proposed hangar development consists of two temporary hangars and the demolition and replacement of Hangar 756 with a new 42,500 square-foot structure that would provide fixed base operator (FBO) hangar and office space. The existing hangar is a 29,998 square foot Quonset-style building that had been relocated from Corsicana, TX in 1947. The outdated building no longer met the need of the GA fleet currently using the Airport. This building would be replaced by a modern FBO facility providing service, maintenance, fueling and shelter for GA aircraft. The proposed hangar development also included the construction of two additional 12,000 square foot temporary hangars on the existing general aviation (GA) ramp area. The proposed hangar development would enable the FBO to provide a higher level of service to GA users and would accommodate existing and forecast aircraft activity more efficiently than the current facilities. These replacement facilities are not expected to generate additional air traffic. Key Environmental Issues All proposed development would occur on an existing ramp, which limited potential impacts to the natural environment. Although National Wetlands Inventory Mapping identified wetlands near the proposed development, that no additional impervious surface would be constructed eliminated concerns about the effects of altered drainage patterns on those wetlands. The lack of new impervious surface and the similarity of the former and proposed uses of the site minimized the need to modify the airportâs National Pollution Discharge Elimination System (NPDES) permit. The following two issues required the most attention during the NEPA process. Section 106 of the Historic Preservation Act and Section 4(f) of the Department of Transportation Act As noted above, the hangar was relocated to the Airport in 1947, prior to that it had been located at another airport in the region and was used in training World War II military pilots. The architectural historian assigned to evaluate the hangar concluded that, although the relationship with U.S. World War II military aviation was no longer relevant due to the lack of historical context, the hangar was eligible for listing on the National Register of Historic Places (the National Register) because of its association with an important phase in the Airportâs development and its characteristic design. Had this conclusion been accepted, Section 4(f) of the Department of Transportation (DOT) Act would have precluded the FAA from approving the project, unless the sponsor could demonstrate that there was no feasible and prudent alternative that would avoid removing the hangar. The result of this alternatives analysis could have resulted in a less-than-optimal solution from an airport development perspective. The FAA transmitted the architectural historianâs report and recommendations to the State Historic Preservation Officer (SHPO) with a statement that the FAA disagreed with the reportâs conclusions. The SHPO concluded that, in the absence of other structures developed in the area dating from the period of the Airportâs development, the historical context no longer existed and that the hangar was
Case Study Narratives C-5 not eligible for listing on the National Register. Had the SHPO determined that the hangar was eligible for listing, the sponsor would have had to demonstrate that no other alternative would have met the purpose and need for the proposed action or accepted a less than optimal solution. Subsequently, the FAA received a request from a local historical society at the hangarâs former location. The request was for recovery of artifacts from the hangar prior to its demolition. The FAA forwarded this request to the Airport with a statement to the effect that providing such artifacts would be in keeping with the FAAâs responsibility to promote historic preservation. Hazardous Materials As part of the design process, the Sponsor had an asbestos inspection conducted and subsequently removed the asbestos from the hangar in accordance with state regulations. That effort did not include a lead investigation because it was not required by the state for non-residential structures. The FAA CATEX Standard Operating Procedure does, however, require the removal of lead prior to demolition activities. As demolition could not proceed prior to the completion of the NEPA process, this plan posed a problem as the FAA has no ability to require the airport sponsor to perform future actions, such as remediation, after issuing a CATEX. The Airport could either have the remediation done in advance of the demolition contract or convert the NEPA process to an EA so that remediation could be a condition of the Finding of No Significant Impact. In this case, the sponsor opted to have the hazardous materials investigations and remediation conducted prior to the completion of the CATEX. NEPA Approach The Airport sponsor decided that, to avoid the procedural requirements and costs of converting a nearly completed CATEX to an EA, it would complete the lead remediation in advance of the demolition contract. This decision allowed the FAA to approve the CATEX. This experience highlights the need for airports to know as much as possible about the natural and human environment prior to initiating the NEPA process. In this case, the age of the hangar was identified early in the NEPA process, which enabled the FAA to initiate coordination with the SHPO early; however, the Section 106 consultation process nevertheless extended the time required to obtain NEPA approval. The fact that the FAA requires remediation of hazardous materials prior to approval of a CATEX could pose problems for GA airports in submitting grant applications for projects involving demolition. The FAA requires NEPA approval prior to issuing an Airport Improvement Program (AIP) grant, which means that discovering hazardous materials late in the process could cause an airport sponsor to miss an application submittal deadline. The project was able to continue through the NEPA process as a CATEX; however, the effort required to demonstrate the lack of extraordinary circumstances required specialized subconsultants and lengthy coordination with the FAA and the State Historic Preservation Officer (SHPO) to resolve the issues related to the potentially historic hangar.
C-6 Guidance for Using the Interactive Tool for Understanding NEPA at General Aviation Airports Case Study 3 General Aviation Airport (historical air taxi service) Categorical Exclusion Project Description The airport is in an attainment area, which limits the need for air quality analysis, and is also in a designated coastal zone. The proposed hangar development consists of a 10,000 square-foot public use hangar, a 2,500 square-foot paved hangar access area, and a gravel parking area for three vehicles. The gravel parking area will require no access road as users will drive through a grass area from the access road to access the gravel parking area. The hangar would allow the Airport to provide a much-needed public service and become more financially self-sustaining. The Sponsor would build the hangar to be compatible with other hangars built recently on the field by private entities. The proposed hangar development would maintain or enhance the level of service for GA users, and would accommodate existing and forecast aircraft activity more efficiently than the current facilities. This facility is not expected to generate additional air traffic. Key Environmental Issues The Airport is located in a semi-rural area. The project site is located on grassland entirely on airport property. The site has been regularly mowed and maintained since 1997, and is otherwise undisturbed. The Sponsor must acquire a building permit from the local municipality. Biological Resources The CATEX effort included a Wildlife Hazard Site Visit. For an airport with less than 75,000 annual operations, a one to three day assessment by a certified wildlife biologist is sufficient. The site visit documented the airportâs wildlife history, suspected wildlife hazards, habitat attractants, control activities, airport operations procedures, and communications of hazards to airport operations. Information from USFWS Information for Planning and Consultation and the Wildlife Hazard Site Visit indicated that the project site did not include areas classified as habitat for any species listed as endangered or threatened. The Wildlife Hazard Site Visit Report stated that sightings of endangered species have been reported on the airport or in the local area, and these areas did not contain suitable habitat for listed species. Coastal Resources The airport is located about 2.5 miles from the closest coastal barrier resource. Although the Airport falls within the boundaries of the state coastal management program, the airport is identified as being consistent with the programâs policies. The proposed project would not directly or indirectly alter the uses of a coastal zone in a manner that would be inconsistent with the stateâs program. Wetlands In addition to research using National Wetlands Inventory (NWI) mapping, a field investigation was performed by a qualified wetlands biologist to confirm the absence of wetlands or other waters of the U.S. in or near the project area. The field investigation determined that no wetlands were present in the area to be affected by the proposed project.
Case Study Narratives C-7 Water Quality The project would not alter drainage patterns on the Airport, but would slightly increase the total impervious surface. Open turf ditches would be used to contain the runoff. While an increase in surface drainage to a major water body would occur, compliance with the conditions of the airportâs National Pollutant Discharge Elimination System (NPDES) construction and operational permits would minimize the potential effects on water quality. Through the CATEX process, the sponsor committed to implementing BMPs to preserve neighboring water sources. BMPs identified in the CATEX document included the placement of sediment barriers such as silt fences and/or hay bales around construction activity to avoid fine material from entering any water resources in the airport vicinity. The sediment barriers would be maintained over the course of construction, and would be removed after completion of construction of the proposed project. Stormwater runoff from new impervious surfaces resulting from hangar construction and associated development would be accommodated by the airportâs existing stormwater drainage system. The Sponsor would submit all relevant federal, state, and local environment applications for licenses, permits, and certificates associated with the proposed project. NEPA Approach While the proposed project met the criteria for a CATEX according to FAA Order 1050.1F, the number of potentially affected environmental resources indicated that a documented, as opposed to a simple letter CATEX would be appropriate. The subsequent analysis of the environmental issues described above demonstrated that no extraordinary circumstances would result from construction and implementation of the proposed project. The project was able to continue through the NEPA process as a CATEX; however, the effort required to demonstrate the lack of extraordinary circumstances included a wildlife hazard site assessment and field investigation regarding wetland presence in or near the project area performed by a qualified biologist.
C-8 Guidance for Using the Interactive Tool for Understanding NEPA at General Aviation Airports Case Study 4 Non-Hub Commercial Service (93 percent of operations by GA aircraft) Land Transfer, Non-aeronautical (Commercial) Development Categorical Exclusion Project Description The Airport Sponsor proposed to lease about 15 acres of Airport property for non-aeronautical revenue generating retail establishments. The FAA considered the proposed long-term lease to constitute a release of airport land. The site was a vacant, previously disturbed area that has been excavated for fill dirt. It was accessible by major roadways that would allow project-related construction and operational traffic to reach the project site without driving through residential areas. Key Environmental Issues Several Native American tribes could have interests in the area, and portions of the site might possibly contain archaeological resources. A bicycle/pedestrian trail, which would be classified as a recreational facility is located adjacent to the site. In addition, although much of the site had previously been disturbed, it still contained natural resources that could be affected. Archaeological and Cultural Resources The Area of Potential Effect (APE) comprised the project area previously described (undeveloped but previously disturbed). The Proposed Project would not cause changes in aircraft flight patterns or operations at the Airport that could affect historic or cultural resources beyond this area. A certified archaeologist conducted a field survey of the APE in July 2016 that yielded no evidence of archaeological or cultural resources. Additionally, there were no National Register of Historic Properties (NRHP) in the APE. The closest historic property was over five miles from the APE. The archaeologist recommended that no further archaeological investigations were required for the Proposed Project. Consultation with the SHPO on the appropriateness of the APE and on the finding of No Historic Properties Affected resulted in receiving the SHPO's concurrence over a period of about one month. DOT Section 4(f) A bicycle/pedestrian trail adjacent to the site is considered a Section 4(f) property due to its function in the local and regional public recreation network. The project would not have required the relocation of the bicycle/pedestrian trail within the project area either during construction or after implementation, and would not have resulted in direct âtaking.â Analysis of operational and construction impacts concluded that the project would not have severely degraded the intended commuting and recreation use of the trail; therefore, no constructive use of the Section 4(f) resource would occur. Migratory Bird Treaty Act Field surveys determined that a migratory bird species was present on the site. Construction of the project would therefore have the potential to take birds protected by the Migratory Bird Treaty Act. Consultation with the USFWS determined that the Airport Sponsor could haze and harass migratory birds, as well as destroy inactive nests during construction activities outside of nesting season;
Case Study Narratives C-9 however, no live birds could be taken because of construction activities. The Airport Sponsor committed to adhering to USFWS regulations regarding nest destruction and Migratory Bird Conservation Actions to minimize the risk of taking migratory birds. These regulations recommended that a qualified biologist conduct a survey of the project area seven to ten days prior to starting construction activities. Should nesting migratory birds be found prior to construction activities, the Airport Sponsor would coordinate with the USFWS, Migratory Birds Permit Office. Wetlands A site survey identified a single small wetland on the site. The wetland was not considered jurisdictional and no further coordination with the USACE was required. The FAA concurred with this determination. Surface Transportation Implementation of the project would generate new traffic to the project area. In addition, construction would require a temporary lane closure on an adjacent roadway. A surface traffic study found that, with some improvements to existing surface roadways, the proposed project would not significantly decrease roadway Level of Service. Additionally, the regional transportation planning agency stated that it would coordinate final site plans and applicable permits with the local government and State Department of Transportation. Air Quality The airport is located in a marginal non-attainment area for ozone, and in a maintenance area for carbon monoxide and particulate matter 10, which required that the project be shown to be consistent with the State Implementation Plan (SIP). The proposed project would not have increased aviation activity, which limited the potential impacts to construction activity and the possibility that the retail activity could generate additional surface traffic. A construction emissions inventory determined that the construction activity would not exceed the de minimis levels established in the General Conformity Rule. Similarly, a surface traffic emissions inventory determined that the retail activity proposed for the site would not generate traffic that would exceed de minimis thresholds. The proposed project was therefore presumed to conform to the SIP. The EA concluded that, because both construction and operational emissions would remain below de minimis levels, it was very unlikely that concentrations of criteria pollutants would exceed any NAAQS. No dispersion modeling was conducted. NEPA Approach While the proposed project met the criteria for a CATEX according to FAA Order 1050.1F, the number of potentially affected environmental resources indicated that a documented, as opposed to a simple letter CATEX would be appropriate. The subsequent analysis of the environmental issues described above demonstrated that no extraordinary circumstances would result from construction and implementation of the proposed project. The project was able to continue through the NEPA process as a CATEX; however, the effort required to demonstrate the lack of extraordinary circumstances was substantial and included the following special studies and/or consultations. ⢠FAA and SHPO consultation supported by field work conducted by a qualified archaeologist ⢠Assessment of potential Section 4(f) issues included analysis of construction and operational impacts
C-10 Guidance for Using the Interactive Tool for Understanding NEPA at General Aviation Airports ⢠Consultation with USFWS regarding MBTA issues supported by field work conducted by specialized consultants ⢠Wetland and biological resources site surveys by qualified biologists ⢠Preparation of a construction emissions estimate ⢠Preparation of a traffic impact study and consultation with regional transportation officials
Case Study Narratives C-11 Case Study 5 Non-Hub Commercial Service (93 percent of operations by GA aircraft) Non-Aeronautical (Aircraft Manufacturing) Development Environmental Assessment Project Description An aircraft manufacturer, proposed to construct a new aircraft completions facility at the Airport. The manufacturer occupied 12 different hangars at the Airport and the proposed project would consolidate their operations into one facility. The 12 newly vacant hangars would be leased by the Airport Sponsor to new tenants. The proposed project would introduce a new aircraft at the Airport. In addition to the construction impacts of this project, the EA accounted for the additional 160 aircraft landings and takeoffs (LTOs) associated with test flights of completed aircraft. The proposed project would disturb up to eighteen acres of previously disturbed, unpaved area. Key Environmental Issues Historic, Architectural, Archaeological, and Cultural Resources The Area of Potential Effect (APE) comprised the project area previously described (undeveloped but previously disturbed). The proposed project would not cause changes in aircraft flight patterns, but would increase operations at the Airport due to additional LTOs that could affect historic or cultural resources. A certified archaeologist conducted a field survey of the APE for a previous project that yielded no evidence of archaeological or cultural resources. Archaeological field surveys are valid for five years and the FAA concurred that the findings from that survey of the APE remained valid for the proposed project. Additionally, there were no National Register of Historic Properties (NRHP) in the APE. The closest historic property was over three miles from the APE. The archaeologist recommended that no further archaeological investigations were required for the proposed project. Consultation with the SHPO on the appropriateness of the APE and on the finding of No Historic Properties Affected resulted in receiving the SHPO's concurrence over a period of about one month. Native American Tribal Consultation According to the United States Department of Housing and Urban Development Tribal Directory Assessment Information, six Native American tribes might have had an interest in the Airport area. Although the project would have little likelihood of affecting archaeological resources and would not affect tribal land or land of interest to tribes, consultation with the relevant Tribal Historic Preservation Officer (THPO) was conducted through the FAA. The FAA consulted with each THPO and received a response from only one tribe requesting additional information. Air Quality The airport is located in a marginal non-attainment area for ozone, and in a maintenance area for both carbon monoxide and particulate matter 10, which required that the project be shown to be consistent with the State Implementation Plan (SIP). A construction emissions inventory using the ACEIT quantified construction-related emissions associated with the project. These results showed that temporary construction-related emissions resulting from the project would remain well below de minimis thresholds for a marginal non-attainment ozone area, for a carbon monoxide and particulate
C-12 Guidance for Using the Interactive Tool for Understanding NEPA at General Aviation Airports matter 10 maintenance area, and all other criteria pollutants. An operational emission inventory using the AEDT, Version 2b, quantified potential emissions because of operating additional PC-24 flights induced by the project. These results show that operational emissions would also remain below de minimis thresholds. The EA concluded that, because both construction and operational emissions would remain below de minimis levels, it was very unlikely that concentrations of criteria pollutants would exceed any NAAQS. No dispersion modeling was conducted. Fish, Wildlife, and Plants The EA had to resolve several biological issues. A biological survey of the project area conducted on January 2016 identified eighteen federally- and state-listed species protected under the Endangered Species Act (ESA) and state protected list maintained by the Colorado Parks and Wildlife (CPW) respectively, that might have been present in the project area. The project area also provided some potential nesting and foraging habitat for a variety of ground-nesting bird species protected by the Migratory Bird Treaty Act (MBTA). In addition, while there is no federal special purpose law addressing noxious weed species, several state listed noxious weeds were found in the project area. The EA resolved these issues as described below. Endangered Species Act. Although the site survey of the project area indicated that federal- and state-listed endangered or threatened species are found in the area, the EA concluded that project construction would not affect federally-listed endangered or threatened species due to the use of construction BMPs (e.g., nest surveys prior to construction during nesting season, clearing of vegetation prior to nesting season, etc.). Operationally, the Airport Sponsor has a requirement to ensure the safety at the Airport by managing wildlife hazards and the proposed project did not change this requirement. Additionally, the FAA consulted with the USFWS regarding the lack of project effects to federally listed species and received concurrently within one month. The Airport Sponsor consulted with the CPW on the lack of project effects on state-listed species and received concurrence within one month. Migratory Bird Treaty Act. If construction activities were to be scheduled during the annual nesting season (May to August), fine-scale systematic nest surveys would be required under the MBTA. Vegetation clearing outside of the bird-nesting season would not constitute a taking under the MBTA. Concerns for nesting birds were offset by FAA requirements for the Airport Sponsor to manage wildlife hazards. Such efforts already discouraged the presence of nesting birds, breeding mammals and animals that attract predators, in addition to vegetation that would attract such wildlife. Noxious Weeds. Three noxious weed species were identified during the January 2016 survey of the project area. The Airport Sponsor committed to the following weed management techniques and preventative BMPs as mitigation: (1) avoidance of driving in any identified noxious weed infested areas; (2) vehicle inspections for weed seeds stuck in tire treads or mud on the vehicle; (3) prevention of cleaning infested vehicles in weed free areas; (4) heavy equipment inspections for noxious weed seeds before exiting infested property; (5) use of hay, straw, or mulch that has been certified weed free; and (6) development of protocols to prevent the spread of noxious weeds encountered during construction.
Case Study Narratives C-13 Wetlands Three wetlands and a drainage swale were identified during a January 2016 survey of the project area. All three wetlands and the drainage swale were determined to be non-jurisdictional wetlands, thereby not requiring a Section 404 permit from the USACE. The Airport Sponsor consulted with the USACE regarding the non-jurisdictional determination for the three wetlands and drainage swale and received concurrence within one week. Noise The potential noise effects of the proposed project were evaluated using the Area Equivalent Method (AEM) Version 7.0d. The analysis compared two future scenarios, the proposed project and the No Action Alternative. The AEM analysis indicated that the proposed project would result in a 0.1 percent increase in the size of the 65-Day-Night-Sound-Level (DNL) noise contour. A significant noise effect occurs when the 65 DNL noise contour increases by 17%. The EA concluded that no significant noise impact would occur because of the proposed project. NEPA Approach The proposed project did not met the criteria for a CATEX according to FAA Order 1050.1F; specifically, Section 5-6.4(f)âs criteria for âlimited construction of accessory on-site structures.â In addition, given the number of potentially affected environmental resources, the FAA determined that a more detailed NEPA document would be appropriate. The subsequent analysis of the environmental issues described above demonstrated that no significant impacts would result from construction or operation of the proposed project; however, the level of effort required to reach that conclusion was substantial and included the following special studies and/or consultations: ⢠FAA and SHPO consultation supported by a previous survey of the project area ⢠Preparation of construction and operations air pollutant emissions estimates using separate specialized models ⢠Preparation of operational noise estimates using a specialized model ⢠Consultation with USFWS on ESA and MBTA issues supported by field work conducted by specialized consultants ⢠Consultation with CPW on state endangered species issues supported by field work conducted by specialized consultants ⢠Consultation with USACE on the jurisdictional determination of wetlands within the project area supported by field work conducted by specialized consultants ⢠Wetland and biological resources site surveys by qualified biologists
C-14 Guidance for Using the Interactive Tool for Understanding NEPA at General Aviation Airports Case Study 6 General Aviation Airport Taxiway Extension and Rehabilitation Categorical Exclusion Project Description The airport sponsor City proposed the extension of an existing partial parallel taxiway to connect with the southern threshold of the runway. This included clearing and grading for the taxiway extension, drainage improvements that would include a new open channel, an inlet and cross-drain under the proposed taxiway extension to tie into the existing storm drainage system, revegetating disturbed areas, and pavement marking of the completed operational surfaces. In addition, the existing access taxiway pavement in the T-hangar area would be rehabilitated and the existing on-Airport access taxiway that provides access to the off-Airport Air Evac hangar would be widened. Key Environmental Issues Air Quality The airport is located in an attainment area for all criteria pollutants and is exempt from conformity requirements. However, the construction activities that would occur with the extension of Taxiway A would result in air pollutant emissions related to construction equipment and in earthmoving activities. A variety of Best Management Practices (BMPs) were identified to minimize the impacts associated with these temporary air pollutant emissions. Farmlands As designated by the U.S. Department of Agriculture, prime farmlands exist at the Airport. Approximately 2.3 acres of designated prime farmland would be affected by the extension of Taxiway A. As a result, coordination with the Natural Resources Conservation Service (NRCS) occurred. The 2.3 acres of Airport land represent a small fraction of the number of acres of prime farmland in the county (less than 0.005 percent) and because the Airport was operational prior to 1984, the impacts to prime farmland were not considered significant. NEPA Approach While the proposed project met the criteria for a CATEX according to FAA Order 1050.1E, the State Department of Transportation, Aviation Section, required that a documented CATEX be prepared to document all of the potential issues associated with the implementation of the proposed project. In addition, the Aviation Section requires consultation with numerous federal agencies to ensure that all environmental resource issues were adequately documented and addressed. This approach enabled the State to determine that no extraordinary circumstances would occur in association with the proposed project and that a CATEX was the appropriate NEPA document.
Case Study Narratives C-15 Case Study 7 General Aviation Airport Runway Reconstruction Categorical Exclusion Project Description The proposed action as the implementation of a Pavement Management and Maintenance Plan to repair and rehabilitate two subsidence areas on the runway. A report was prepared that addressed the issues associated with subsidence areas and included soils and geotechnical investigations to better understand the issues associated with the subsidence areas. The proposed action would involve the installation of pavement panels that would be supported by four helical anchor piles. Pre- drilling would be done through the very stiff clay fill above the organic soils to eliminate down-drag and to extend the helical anchors through the clay, through the organic layer and into the bearing stratum below the organic soils. The construction would take place during the night and the runway would then be open during the following afternoon. Key Environmental Issues Air Quality The airport is located in a non-attainment area for ozone and particulate matter. Thus, the analysis of construction activities was focused on the emission of criteria air pollutants and the implementation of Best Management Practices (BMPs) to reduce the impacts associated with construction activities. Wetlands The soils at the Airport are conducive to ponding, and wetlands exist near the runway. The CATEX included an analysis of the changes in drainage that would occur with the rehabilitation of the runway and the changes in soil composition in the runway vicinity. With the design of the drainage system associated with the runway rehabilitation, no impacts to adjacent wetlands would occur. NEPA Approach The proposed project met the criteria for a CATEX according to FAA Order 1050.1E. Of particular concern in determining that no extraordinary circumstances would occur with the implementation of the proposed action were the impacts associated with construction. The proposed action was required to repair a runway that was being severely compromised because of subsidence and a quick resolution was necessary. Because of urgency of the proposed action, coordination with all agencies was a priority to ensure that regulators understood the need for the proposed action and that all impacts were thoroughly disclosed in the CATEX.
C-16 Guidance for Using the Interactive Tool for Understanding NEPA at General Aviation Airports Case Study 8 General Aviation Airport Non-aeronautical Development Programmatic Environmental Assessment Project Descriptions The airport sponsor desired to make the airport more financially self-sufficient by developing about 450 acres in aeronautical and non-aeronautical revenue generating uses. The most recent airport master plan determined that the area was not required to meet forecast aviation demand. The anticipated future uses include aeronautical uses, aviation and non-aviation related manufacturing, offices, and commercial enterprises. The proposed development is adjacent to the airfield but, because no taxiways currently provide access to the site, the proposed development includes a taxiway to support future aeronautical uses. The airport sponsor had received a development proposal for a portion of the site, but wished to enhance the marketability of the site by providing the infrastructure to support future development. Key Environmental Issues The proposed development occupied a previously graded, but currently vacant area. In the more recent past, large portions of the area had been farmed. The area is adjacent to a large mostly residential planned development on one side and an extensive area partially developed in commercial and industrial uses. Historic, Architectural, Archeological, and Cultural Resources Historical aerial photography showed that the area contained terrain features that are often associated with pre-historic Native American habitation. An archaeological field survey of the site found no indication of pre-historic habitation because earlier grading had eliminated any potential remains. The report was submitted to the SHPO via the FAA and no further investigations were recommended. Air Quality The Airport is located in a marginal nonattainment region for ozone; the associated de minimis level for each of the ozone precursors, volatile organic compounds (VOC) and nitrogen oxides (NOx), is 100 tons per year. Air pollutant emissions are time sensitive in that emissions in one year are not added to those of another year. For that reason, the construction emissions estimates were prepared for the first increment of development (Phase I) only because the extent and timing of future development could not be predicted. Future development would likely require additional air quality analyses, although preliminary estimates indicated that construction emissions for future development would also likely fall below de minimis levels. The air quality analysis for Phase I development was split into two categories that separately examine construction and surface vehicle emissions generated by commuter and commercial vehicles. ⢠The construction emissions inventory using the ACEIT quantified construction-related emissions associated with the project. These results showed that temporary construction-
Case Study Narratives C-17 related emissions resulting from the project would remain well below de minimis thresholds for maintenance area. ⢠Vehicular emissions resulting from operation of Phase I development were considered to be consistent with the SIP because the project was consistent with future development anticipated in the region and would draw employees from the region. The new development, therefore, would not represent an increase in regional vehicle trips. The EA concluded that, because both construction and operational emissions would remain below de minimis levels, it was very unlikely that concentrations of criteria pollutants would exceed any NAAQS. No dispersion modeling was conducted. Fish, Wildlife, and Plants Federally listed species protected under the Endangered Species Act (ESA) occur in the region and might have been present on the site. A field survey of the entire site found no evidence of the listed species or their habitats, although a small forested area that could provide limited nesting, foraging, and shelter habitat for a variety of grassland birds and raptors protected by the MBTA. The EA concluded that, if construction activities were to be scheduled during the annual nesting window, fine-scale systematic nest surveys would be required under the MBTA. Wetlands and Other Waters of the U. S. The field survey for fish, wildlife and plants also investigated wetlands and waters of the U. S. The survey identified seven non-jurisdictional wetlands totaling 1.8 acres and 1.2 acres of jurisdictional streams. The wetlands were small and scattered throughout the proposed development site. In contrast, the jurisdictional streams were concentrated in one portion of the property. While the non- jurisdictional wetland impacts would not require a wetland permit from the USACE, Executive Order 11990 requires the FAA to approve projects involving wetlands fill only if no practicable alternative exists. The EA concluded that any substantial development in the project area would so alter the drainage patterns that the existing wetlands would no longer be supported. This finding allowed the sponsor to investigate mitigation options such as the use of wetlands mitigation banks; an FAA preferred approach. Surface Traffic Planning documents developed for the sponsor estimated traffic volumes and distribution on the major roadways serving the area. That analysis concluded that the additional traffic associated with Phase 1 development would not cause an unacceptable reduction in roadway levels of service, but that mitigation might be required to maintain acceptable levels of service as later development came on line. The EA identified potential mitigation measures to accommodate the build-out of the project, but those measures would not be required until future development became more immediate. NEPA Approach Given the speculative nature of commercial development, uncertainties regarding the environmental setting, and the uncertain timeframe for development, the FAA EPS directed the airport sponsor to prepare a Programmatic EA based on the best available information about the nature and timing of future development. In concept, the FONSI or FONSI/ROD for such a programmatic EA establishes development intensity thresholds and other conditions on future development. If development
C-18 Guidance for Using the Interactive Tool for Understanding NEPA at General Aviation Airports proposals materialize within the âshelf lifeâ of the NEPA document (currently 3 years after approval), it is covered by the FONSI or FONSI/ROD providing that it complies with the established conditions. Development proposals occurring after the expiration of the shelf life would require NEPA approval. Proposals conforming to the conditions established in the FONSI or FONSI/ROD could be approved through a simple written re-evaluation confirming that the findings and approvals of the original NEPA document remain valid. If the specifics of the proposal differ somewhat, a supplemental EA might be appropriate. Differences that are more substantial could require preparation of a new EA, although much of the original NEPA document might still be useable. While the proposed might have been consistent with the criteria for a CATEX according to FAA Order 1050.1F, the scale of development and uncertainties about the exact uses that might be developed made the application of a CATEX unrealistic. The analysis of the environmental issues described above demonstrated that no significant impact would occur; however, the effort required to demonstrate the lack of significant impacts was substantial, and included the following special studies and or consultations. ⢠FAA and SHPO consultation supported by field work conducted by a qualified archaeologist ⢠Wetland and biological resources site surveys by qualified biologists ⢠Preparation of a construction emissions estimate ⢠Preparation of a traffic impact study
Case Study Narratives C-19 Case Study 9 General Aviation NPIAS Reliever Airport Airfield Safety Enhancement Project Environmental Assessment Project Description The Airport proposed to enhance safety by capping an open-air creek that bisects the airfield to eliminate a wildlife attractant. The original project also involved the realignment of a taxiway to accommodate planned landside development. The proposed project resulted in the conversion of 0.19 acres of wetlands. During the NEPA process airfield planning significantly altered the project definition by eliminating the taxiway component. This change in project definition, coupled with the Regional Water Quality Control Boardâs request for consideration of new alternatives delayed the NEPA process. Key Environmental Issues Air Quality The airport is located in a marginal non-attainment area for ozone and particulate matter 2.5 and a maintenance area for carbon monoxide, which required the NEPA process to demonstrate that construction emissions would be consistent with the SIP. A construction emissions inventory using the ACEIT quantified construction-related emissions associated with the project. These results showed that temporary construction-related emissions resulting from the project would remain well below applicable de minimis thresholds for all other criteria pollutants. The EA concluded that, because construction emissions would remain below de minimis thresholds, it was very unlikely that concentrations of criteria pollutants would exceed any NAAQS. No dispersion modeling was conducted as part of the EA. Fish, Wildlife, and Plants A biological field survey indicated that no Federal or State protected species were likely to inhabit the stream channels or area of potential ground disturbance. Bird species protected under the Migratory Bird Treaty Act were identified during the field survey. Coordination with the United States Fish and Wildlife Service resulted in the establishment of mitigation procedures that required a buffer of 50 feet between construction areas and nesting birds, in the event nesting migratory birds were encountered. Water Quality A water quality certification under Section 401 of the Clean Water Act was required because the proposed project involved placing a surface water body in a closed culvert. The affected stream was a tributary of an impaired waterbody and, consequently, the Regional Water Quality Control Board required the sponsor to identify and âopenâ other covered stream segments to daylight as mitigation for the effects of removing the affected stream section from exposure to daylight.
C-20 Guidance for Using the Interactive Tool for Understanding NEPA at General Aviation Airports Wetlands Three wetlands totaling 0.19 acres were identified during a March 2013 wetland delineation of the project area. Coordination with the USACE indicated all three wetlands were jurisdictional and would require a Section 404 permit. The total area the wetlands impact did not exceed 0.5 acres, which qualified the project for a Nationwide Permit 39 for Commercial and Institutional Developments. Coordination with the USACE also indicated a stream channel and wetland habitat purchase mitigation ratio of 1:1. NEPA Approach The proposed project did not meet the criteria for a CATEX because of the anticipated wetland impacts and potential for fish, wildlife, and plant, as well as water quality impacts that were identified in the scoping phase. Early coordination with the USACE and regional water quality entities was an important component of the initial coordination process. The analysis of the environmental issues described above demonstrated that no significant impact would occur; however, the effort required to demonstrate the lack of significant impacts was substantial and included the following special studies and or consultations. ⢠FAA and SHPO consultation supplemented by a previous survey of the project site ⢠Preparation of construction and operations air pollutant emissions estimates using a specialized model ⢠Consultation with the RWQCB on alternatives considered, stream channel mitigation ratios and use of best management practices (BMPs) to be implemented during construction ⢠Consultation with USFWS on MBTA issues supported by field work conducted by qualified consultants ⢠Consultation with USACE on the jurisdictional determination of wetlands within the project area supported by field work conducted by specialized consultants ⢠Wetland and biological resources site surveys by qualified biologists
Case Study Narratives C-21 Case Study 10 General Aviation Airport Rotating Beacon and Airport Weather Surveillance System (AWOS) Categorical Exclusion Project Description The small airport was not equipped with adequate weather-monitoring equipment. The proposed Airport Weather Observing System (AWOS) would use the existing electrical power source located at the site of the airportâs rotating beacon, which was to be replaced as a part of the project. An underground utility line would connect this electrical source to the proposed AWOS. The proposed AWOS would transmit atmospheric data via a high-frequency signal to other NAVAIDS and the proposed AWOS would transmit atmospheric data via a high-frequency signal to other NAVAIDS and the air traffic control tower. The utility line would traverse an airfield infield area that does not contain wetlands or protected species. The Project site is located within 2,000 feet of the ocean, 500 feet from a creek and 500 feet from a nature preserve. Key Environmental Issues Coastal Zone The Airport is located in the state coastal zone. The countyâs local coastal plan policies were certified by the state and formally adopted by the County Board of Supervisors. The corresponding Coastal Zone Land Use Ordinance, also adopted by the County Board of Supervisors, listed the airport as a permissible use, which includes âappurtenant areas used for airport buildings, aircraft operations and related facilitiesâ. The CATEX concluded that an airport AWOS system was an integral part of the airportâs facilities for air navigation and was therefore consistent with the facilities permitted in appurtenant areas. A request for a consistency determination sent to the county resulted in the issuance of a letter stating that the Project would be consistent with the goals and policies of the Local Coastal Plan. Ecological (Biological) Resources According to the USFWS Critical Habitat Mapper, the closest USFWS designated critical habitat was located approximately 0.2 mile from the project site. This critical habitat was designated to protect an endangered species native to coastal scrub, sand dunes, and marshes. An ecological constraints field survey of the Project site did not find any occurrence of this or any other listed species. DOT Section 4(f) The airport is located 500 feet from a designated natural preserve. The project would have no direct effect on the natural preserve and the proposed rotating beacon replacement would not differ substantially from the existing beacon. Floodplains The entire project site is located in a floodplain influenced by the nearby creek and the ocean. The entire Airport is located within a 100-year floodplain; therefore, there was no alternative to installing the AWOS in the floodplain. The Project would not add fill to the floodplain or materially increase
C-22 Guidance for Using the Interactive Tool for Understanding NEPA at General Aviation Airports impervious surfaces. For these reasons, the Project would not adversely affect the beneficial values of the floodplain. Air Quality With regard to air quality, extraordinary circumstances that would preclude the use of a CATEX for NEPA compliance include not conforming to the SIP and/or exceeding any NAAQS. The project did not involve an airport capacity enhancement that would have operational effects; therefore, the air quality analysis was limited to construction emissions. Conformity. The proposed development was consistent with the FAA's description of "routine maintenance and repair activities" and "routine installation and operation of airport navigation aids", which are presumed to conform with the SIP in accordance with the General Conformity Rule (72 Federal Register (FR) 145). The CATEX documented that the proposed development was presumed to conform and no further analysis was required. NAAQS. NAAQS are based on pollutant concentrations, which can only be positively determined through costly dispersion analyses. In practice, dispersion analyses are not conducted for construction activity. The FAA agreed with the assumption that the project was presumed to conform and indicated that it was highly unlikely to exceed the NAAQS. No further analysis was required. Lighting and Visual Impacts The AWOS installation would require obstruction lighting, but such lights would be shielded from surrounding off-airport areas by vegetation and would be less visible to the community than the existing Airport rotating beacon in the same general location. This obstruction lighting would not be intrusive. NEPA Approach The proposed project clearly met the criteria for a CATEX according to FAA Order 1050.1F. The airportâs location in coastal zone and in a non-attainment area, and the possibility that an endangered species might be found on the site required additional coordination and/or investigations. The project was able to continue through the NEPA process as a CATEX. The effort required to demonstrate the lack of extraordinary circumstances was modest and included the following special studies and/or consultations. ⢠Coordination with the local coastal zone administrator ⢠Construction emissions inventory ⢠Field investigation for listed species and confirmation that wetlands were not present
Case Study Narratives C-23 Case Study 11 General Aviation Airport Runway Extension and Runway Safety Area Improvements Environmental Assessment Project Description The runway extension is intended to meet the following objectives. ⢠Increase the Airport capability to support regional aerial fire suppression operations ⢠Improve the existing northeastern Minnesota aerial fire suppression geographical coverage ⢠Improve the takeoff and landing distance related to the existing runway length, thus increasing safety for aircraft using the runway ⢠Support statewide and federal aerial fire suppression goals and objectives ⢠Provide an improved connection to the state and federal air transportation system via increased runway length that accommodates a wider range of aircraft now and in the future. Four alternatives to the runway extension and widening were considered in the EA. An alternative providing the entire desired extension in a single direction away from existing wetlands was found to have the least amount of wetland impacts and was chosen as the preferred alternative. Key Environmental Issues Coastal Resources The project site is adjacent to the boundary of an area in the stateâs coastal program and a Federal consistency review was completed and submitted to the state environmental agency, which determined that the project was consistent with the coastal program policies. Fish, Wildlife, and Plants The project area contained proposed Critical Habitat for a federally listed threatened species. The CH designation is based on the presence of the physical and biological features that are used to define the CH and that are necessary to the conservation and management of the species. The CH extends over seven states and encompasses about 8,226 square miles of land. The area defined as a CH is not necessarily occupied by the species but may be essential for the conservation of the species. Although the airport is in the CH, it is not considered a prime habitat for the species and the issue was resolved on that basis. Historic, Architectural, Archaeological, and Cultural Resources The Airport is bisected by the remnants of an Indian trail. The trail is included on historic maps and was considered a primary trail for travel by Native American tribes in the area. The location of the trail was approximately at the midpoint of the runway. Although the runway extension would be constructed more than 1,500 feet from the location of the trail as depicted on the historic map, a survey was conducted on Airport property to locate the trail. No evidence of the trail was found. Coordination with two local Native American tribal communities occurred throughout the preparation
C-24 Guidance for Using the Interactive Tool for Understanding NEPA at General Aviation Airports of the EA to obtain information and ensure that the tribal communities were afforded the opportunity to comment on the proposed runway extension. Wetlands A wetland delineation was completed and all wetlands were mapped and verified by the USACE. Of the four alternatives studied, the Preferred Alternative had the least amount of wetland impact. The selection of the alternative having the least wetlands impact was instrumental in enabling the project to be approved under Section 404 of the Clean Water Act, subject to USACE and state approval of a wetlands mitigation plan. NEPA Approach The key element of the approach to the Environmental Assessment was the development and analysis of four alternatives that would meet the purpose and need of the proposed action. This approach enabled the FAA to identify the alternative that had the least environmentally damaging effects. This approach required coordination with other Federal agencies, State agencies, and Native American tribal communities.
Case Study Narratives C-25 Case Study 12 General Aviation Airport Aeronautical Development and Supporting Infrastructure Environmental Assessment Project Description The airport sponsor of a large GA airport with substantial corporate aviation activity proposed to redevelop and upgrade GA facilities in one portion of the airport and to develop another previously undeveloped parcel of airport property to maximize its potential to accommodate aviation related activities. The goal for this development was to enhance the financial self-sufficiency of the airport. Specific improvements included: on-airport roadway improvements, FBO building and parking lot reconstruction, corporate hangar/building and parking lot construction, T-hangars demolition/replacement and construction and T-hangar parking lot, new or relocated taxi lanes, new hangars, maintenance and storage buildings, utility extensions, and fencing. Key Environmental Issues Floodplains The proposed development would encroach into a 100-year floodplain and designated floodway. Executive Order 11998, Floodplain Management and USDOT Order 5650.2, Floodplain Management and Protection preclude the FAA from approving development that occupies or modifies the 100-year floodplain and to avoid direct or indirect support of floodplain development wherever there is a practicable alternative. Analysis of areas outside of the floodplain concluded that only three areas contained sufficient space to develop the types of facilities required to meet the purpose and need for the project; the two areas incorporated in the proposed project and one additional area. About 23 acres of the two areas included in the proposed project fall within the 100-year floodplain, while about 25 acres in the third area fall within the 100-year floodplain. Collectively, this area contained about 48 acres in the 100-year floodplain. By avoiding the third area and limiting the development footprint in the first two areas, the impact of the proposed project was reduced to 15 acres of floodplain encroachment. To comply with minimum floodplain standards required by the National Flood Insurance Program (NFIP), new structures and a portion of the existing airport access road within would be raised above the base flood elevation. Placing fill in the floodplain could adversely affect the floodplainâs natural storage values and functions, which could result in loss of water storage during flood events. A floodplain analysis conducted using Hydrologic Engineering Centerâs River Analysis System concluded that the proposed project would not increase the 100-year flood elevation or change flood boundaries. Mitigation identified to minimize impacts of the development on the existing floodplain boundaries and flood elevations included providing additional floodwater storage capacity and using culverts to convey floodwaters. Wetlands A wetland field delineation of the project site was conducted and the USACE confirmed the wetland and resulting wetland boundaries. The delineation revealed about 4.8 acres of wetlands and 114 linear feet
C-26 Guidance for Using the Interactive Tool for Understanding NEPA at General Aviation Airports of intermittent/perineal waterway within the area of ground disturbing activities. Executive Order 11990 prohibits the FAA from approving development that would fill wetlands if a practicable alternative exists. The alternatives screening process identified above resulted in the avoidance of wetlands as well as floodplain impacts. The proposed project would affect 1.52 acres of wetland, largely due to changes in drainage patterns that would reduce the viability of wetlands in the project areas. Activity resulting in the dredging, filling, or altering of the jurisdictional waters of the U.S. present may require a permit from the USACE or the stateâs Department of Environmental Quality. Surface Water and Stormwater Runoff The project would increase the amount of impervious surface, which would increase stormwater runoff. The state regulates surface water quality and quantity through the National Pollution Discharge Elimination System (NPDES) permit process. To meet these permit requirements, the proposed project would include on-site stormwater management facilities for detention and would employ BMPs to comply with water quality standards. The airport sponsor would amend the airportâs NPDES general permit for stormwater discharges associated with industrial activities, which would include updating the airportâs Storm Water Pollution Prevention Plan (SWPPP) prior to the start of ground disturbing activities. Air Quality The area is a maintenance area for the USEPAâs PM2.5 standard. The area is a marginal nonattainment area for the USEPAâs 2008 O3 standard. The air quality analysis included quantitative analyses of construction emissions and qualitative analyses of operational emissions. Construction emissions. Estimates of construction emissions developed for the entire project showed that emissions would be less than de minimis in any year. No further analysis was required. Operational Emissions. The proposed project is not projected to increase aircraft activity at the airport, but would increase surface traffic due to increased employment. The scale of development indicated that about 30 new employees might find jobs at the new facilities. The EA concluded that, given the scale of the employment opportunity, future employees would be drawn from the regional workforce. Given the comparatively small change in regional employment and the likelihood that future employees would already reside in the region, the proposed project could not materially change vehicle emissions in the region. NEPA Approach As noted above, the proposed project would encroach into a 100-year floodplain and would affect wetlands. Both of these resources are subject to special purpose laws requiring that impacts can only be justified if no practicable alternative exists. The EA evaluated alternatives that might avoid or minimize these impacts through an alternatives screening analysis, which examined the potential for other on-Airport areas to accommodate development similar in nature and magnitude to the proposed project. After eliminating areas that were already fully developed and those that were restricted by reasons of safety or airspace protection, the analysis determined that only three areas could be developed: the two areas in which development was proposed and one additional area. Collectively, this area contained about 48 acres in the 100-year floodplain. The proposed project avoided one area containing about 25 acres in the 100-year floodplain and reduced the development
Case Study Narratives C-27 envelopes in the remaining areas to reduce the potential floodplain impacts from 23 to 15 acres of floodplain encroachment. The proposed project would also affect about 1.5 acres of wetlands due to the interruption of drainage patterns on which these wetlands depended. The alternatives analysis that identified reductions in floodplain encroachment also showed that the proposed project would affect less than one third of the wetlands in the project area. Wetland impacts were unavoidable and mitigation occurred. The analysis of the environmental issues described above demonstrated that no significant impact would occur; however, the effort required to demonstrate the lack of significant impacts was substantial and included the following special studies and/or consultations. ⢠Extensive floodplain modeling and analysis ⢠Wetland delineation by a qualified wetland scientist ⢠Preparation of a construction emissions estimate
