Section 3. Environmental Impact Categories and Other Topics
Chapter 4 of FAA Order 1050.1, “Impact Categories, Significance, and Mitigation,” summarizes the requirements and procedures for environmental impact analyses according to the resource impact category. Executive Orders, DOT and FAA orders, handbooks, memoranda, and guidance documents described in FAA Order 1050.1, paragraph 1-10.13, Environmental Impact Categories, may also contain requirements.
Although all resource impact categories may receive the same level of review and analysis, the level of detail of review and analysis for a particular resource is dependent upon the potential for impact. The following paragraphs address those impact categories that may be required as part of the environmental review for proposed air traffic actions.
- The following environmental resource categories or sub-categories could be impacted by a proposed flight procedure, flight procedure change, or other air traffic related action. Accordingly, they must be included in an EA or EIS for further detailed analysis. For proposed actions that qualify for a categorical exclusion, certain impact categories or sub-categories may still need to be analyzed to achieve compliance with special purpose environmental laws, regulations, and other state and federal requirements. (See FAA Order 1050.1, paragraphs 4-2 f, 4-3.2, and 5-2 b.)
- Air Quality
- Compatible Land Use
- DOT Act; Section 4(f)
- Biological Resources; particularly avian species like birds and bats. As necessary, conduct impact analyses related to bird and bat strikes, as well as noise and light emissions-related impacts to avian and nocturnal avian species.
Biological Resources: Other Species. If the proposed action increases the number of aircraft flights, changes the origins or destinations of flights, the proposed action may also need to be analyzed for the potential for an invasive species to be introduced into the study area (GSA).
A significant impact could occur if the U.S. Fish and Wildlife Service or the National Marine Fisheries Service determines that the action could jeopardize the continued existence of a federally listed threatened or endangered species, or would result in the destruction or adverse modification of federally designated critical habitat. Compliance with Section 7 of the Endangered Species Act may be required.
- Historical, Architectural, Archeological, and Cultural Resources (Historical and Cultural Resources only). Review the potential for adverse effects related to the introduction of visual, atmospheric, or audible elements that diminish the integrity of the significant historic or cultural features that qualify the property for inclusion in the National Register or other federal protections.
- Light Emissions and Visual Impacts. In certain cases, a proposed action may require an analysis of light emissions for potential impacts to avian and nocturnal avian species.
- Natural Resources and Energy Supply (aircraft fuel burn analysis only). Review Council on Environmental Quality (CEQ) June 21, 2019 Draft National Environmental Policy Act Guidance on Consideration of Greenhouse Gas Emissions. (Refer to the official version on the Government Printing Office's govinfo website and on Regulations.gov website at: in Docket No. CEQ-2019-0002.) Until further FAA guidance is provided, continue to calculate aircraft fuel burn in accordance with the methodology referenced in AEE-400 Guidance Memo #3, dated January 12, 2012, Considering Greenhouse Gases and Climate Under the National Environmental Policy Act (NEPA): Interim Guidance, and other currently used tools such as AEDT, to analyze fuel burn.
- Noise. Calculate day-night sound level (DNL) exposure levels for population centroids and unique grid points. For California analyses, CNEL may be provided as a supplemental metric. Use of other supplemental metrics requires coordination with the Rules and Regulations Group, AJV-P2. Change analysis must be conducted as directed in FAA Order 1050.1, Appendix B.
- A proposed flight procedure(s) or other air traffic action would create a significant noise impact if it would increase noise by DNL 1.5 dB or more for a noise sensitive area that is exposed to noise at or above the DNL 65 dB noise exposure level, or that will be exposed at or above the DNL 65 dB level due to a 1.5 dB or greater increase, when compared to the no action alternative for the same timeframe.
- For example, an increase from DNL 65.5 dB to 67 dB is considered a significant impact, as is an increase from DNL 63.5 dB to 65 dB. (See FAA Order 1050.1, Appendix B, Paragraph B-1.5, Significance Determination).
- If the noise screening shows that the proposed procedure(s) would cause such an impact, a CATEX cannot be used, and an EA or EIS must be prepared.
- If the flight procedure(s) or other air traffic action can be modified to reduce the noise below the significance threshold, an EA and mitigated Finding of No Significant Impact (FONSI) may be prepared. (See FAA Order 1050.1, paragraphs 2-3.6, 4-4, and 6-2.3).
- If the noise screening shows that aircraft noise over a noise-sensitive area would increase by 5 dB or more, within the DNL 45-60 dB noise range; or would increase by 3 dB or more within the DNL 60-65 dB noise range, further analysis may be required to determine the potential for the flight procedure(s) to be highly controversial because of the potential noise impacts.
- The determination of the appropriate level of additional analysis should be made in consultation with Mission Support, Policy, Rules and Regulations Group.
- If the noise screening shows that none of the above increases would occur, the results of the noise screening with these conclusions should be attached to the CATEX Declaration and uploaded into the current document management database. (See FAA Order JO 7400.2, Appendix 6.)
- The following environmental resource categories or sub-categories would not normally be affected by a proposed flight procedure or air traffic related action because the resource either does not exist within the study area, or the types of activities associated with a proposed air traffic or air traffic related action would not affect them. Accordingly, the following impact areas and resource categories would not be included in an EA or EIS for further analysis.
- Coastal Resources (Coastal Barriers and Coastal Zones).
- Coastal Barriers. The Proposed Action is not expected to involve any actions (physical changes or development of facilities) that would be inconsistent with management of designated Coastal Barrier Resource System (CBRS) areas. However, if there are coastal zones within the study area, management plans must be reviewed to ensure there are no activities related to aircraft overflight noise in the management plan.
- Coastal Zones. The Proposed Action is not expected to directly affect shorelines or change the use of shoreline zones, or be inconsistent with a NOAA-approved state Coastal Zone Management Plan (CZMP). However, if there are coastal zones within the study area, the CMZP should be reviewed to confirm.
- Construction Impacts. The implementation of new air traffic procedures or other air traffic actions does not normally involve construction activity or ground-based impacts.
- Farmland. The Farmland Protection Policy Act (FPPA) (7 CFR Part 658) regulates federal actions with potential to convert farmland to non-agricultural uses. Implementation of proposed flight procedures or air traffic actions does not normally involve the development of land regardless of use, nor do they have the potential to convert farmland to non-agricultural uses.
- Biological Resources (habitat).
- Air traffic, airspace, and flight procedure changes do not involve ground disturbing activities. They do not normally impact critical habitats.
- The proposed flight procedure or air traffic action would not normally affect habitat for non-avian animals, fish, or plants.
- Floodplains. The proposed flight procedure or air traffic action would not involve the construction of facilities. Therefore, it would not impact nor be affected by locations designated as a 100-year flood event area as described by the Federal Emergency Management Agency (FEMA), and no further analysis is required.
- Hazardous Materials, Pollution Prevention, and Solid Waste. The proposed flight procedure or air traffic action would not involve construction or development, or any physical disturbances of the ground. Therefore, the potential for impact from hazardous materials, pollution, or solid waste is not anticipated, and no further analysis or pollution prevention actions would be required.
- Historical, Architectural, Archeological, and Cultural Resources (except Historical and Cultural).
- Archeological. The proposed flight procedure or air traffic action would not involve any construction, development, or any physical disturbance of the ground, or excavation that could impact archaeological resources on Federal, State, or Indian lands, and therefore, would not impact cultural resources, or affect the physical integrity or access to American Indian sacred or culturally significant sites.
- Architectural. The proposed flight procedure or air traffic action would not involve any construction, development, or any physical disturbance of the ground. Therefore, the potential for impact in relation to architectural compatibility with the character of a surrounding historic district or property is not anticipated. However, in certain circumstances, some analysis of the potential for impacts related to aircraft noise may be required.
- Light Emissions and Visual Impacts (except Visual Impacts). There are no special purpose laws for light impacts and visual impacts. Aviation lighting is required for security, obstruction clearance, and navigation and is the chief contributor to light emissions from airports.
- An impact analysis is necessary when projects introduce new airport lighting that may affect residential or other sensitive land uses.
- In certain circumstances, for example, when high intensity lights shine directly into a residence or have the potential to impact avian or other species, is the effect of light emissions considered potentially significant enough to warrant impact analysis and planning to reduce or mitigate such effects.
- The proposed flight procedure or air traffic action will not normally involve aviation lighting. Therefore, no further analysis is required.
- Natural Resources and Energy Supply (except fuel burn). The proposed flight procedure or air traffic action would not normally involve the use of natural resources or materials. Therefore, no further analysis is required.
- Socioeconomic Impacts, Environmental Justice, and Children's Environmental Health and Safety Risks (except Environmental Justice). Potential impacts in this category as a result of disproportionally high adverse noise and/or air quality impacts are dealt with in the noise and air quality impacts sections, respectively.
- Socioeconomic Impacts. The proposed flight procedure or air traffic action would not involve acquisition of real estate, relocation of residents or community businesses, disruption of local traffic patterns, loss in community tax base, or changes to the fabric of the community.
- Children’s Environmental Health and Safety Risks. The proposed flight procedure or air traffic action would not affect products or substances that a child would be likely to come into contact with, ingest, use, or be exposed to, and would not result in environmental health and safety risks that could disproportionately affect children.
- Water Quality. The proposed flight procedure or air traffic action would not involve any discharges or changes to existing discharges to water bodies, create a new discharge that would result in impacts to water quality, or modify a water body. Therefore, the proposed flight procedure or air traffic action would not result in any direct or indirect impacts to water quality, and no further analysis is required.
- Wetlands. The proposed action would not involve the construction of facilities or infrastructure and would therefore not impact wetlands or navigable waters. Therefore, no further analysis is required.
- Wild and Scenic Rivers. If there are no Wild and Scenic River segments ( located in the study area, the proposed flight procedure or air traffic action would not adversely impact any wild, scenic, or recreational status of a river or river segment included in the Wild and Scenic River System and therefore, no further analysis is required.
- Screening. FAA Order 1050.1 contains a list of air traffic actions which normally do not result in significant impacts to the environment, are identified as categorically excludable actions (CATEX), and therefore, do not require the preparation of an EA or an EIS. One of the requirements for a CATEX determination is to ensure that there are no extraordinary circumstances as defined in FAA Order 1050.1.
- The environmental screening process provides a uniform and consistent approach to identify air traffic actions that qualify for categorical exclusion from full environmental impact review in an EA or EIS, and also identifies extraordinary circumstances and/or the potential for significant impacts associated with proposed air traffic actions. The screening process is based on currently approved FAA impact analysis tools and policies.
- A proponent of an air traffic action can perform a series of relatively simple tests prior to contacting a Service Center Environmental Specialist based on the location of the action (e.g., airport location) that will indicate if a CATEX is applicable.
- Actions that pass the screening tests (see paragraph 32-3-3c1) would normally be eligible for a CATEX, but could still require compliance with special purpose environmental laws, regulations, and requirements such as National Historic Preservation Act (NHPA) Section 106 requirements.
- Passing the environmental screening process indicates that the potential for significant impacts and/or extraordinary circumstances due to aircraft noise is minimal or negligible, and a CATEX is appropriate. The environmental screening documentation should be used by the Service Center Environmental Specialist to support the CATEX determination.
- The recommended practice is to start with simple NEPA document determination tools, switching to more complex ones only if the proposed flight procedure or other air traffic action fails the test for CATEX eligibility. In general, the simple tools evaluate isolated changes to the proposed action with the goal of achieving quick but conservative results and require input of a minimal amount of data. The more complex tools evaluate multiple interdependent changes and require input of a more comprehensive set of data.
- The following are the available tools that can screen proposed flight procedures or other air traffic actions for noise and/or fuel burn and carbon dioxide (CO2) impacts as indicated:
- Pre-Screening Filter. The Environmental Pre-screening Filter was developed to guide users through initial analysis of a flight procedure or other air traffic action to achieve applicability of a CATEX. Using a series of simple questions, the pre-screening filter collects and analyzes flight procedure information to determine the next steps in completing the NEPA process. The filter provides the Service Center Environmental Specialist with information to identify an appropriate CATEX or if additional environmental review is required.
- Noise Screening Guidance Document. Using a series of look-up tables, the document guides users through the process to determine if a CATEX is appropriate or if additional environmental review is required.
- Terminal Area Route Generation Evaluation and Traffic Simulation (TARGETS) Environmental Plug-in. The TARGETS Plug-in allows specialists to design procedures for the terminal environment and assess alternative concepts leading to final designs that consider both operational noise and air emissions constraints. Once the user has performed the analysis, the TARGETS Plug-in provides results detailing any potential increase or decrease in noise due to the proposed air traffic action. The TARGETS Plug-in also leverages the technology of AEDT and provides the capability to conduct tradeoff analysis between noise, fuel burn, and CO2.
- Modeling. If the result of screening indicates that additional analysis is required, then a more complex modeling tool will need to be used. FAA environmental modeling has evolved to a single tool that allows analysis of noise, emissions, and climate impacts and their interdependencies:
- Aviation Environmental Design Tool. AEDT is a software system that dynamically models aircraft performance in space and time to produce fuel burn, emissions and noise. Full flight gate-to-gate analyses are possible for study sizes ranging from a single flight at an airport to scenarios at the regional, national, and global levels.
- AEDT is currently used by the U.S. government to consider the interdependencies between aircraft-related fuel burn, noise, and emissions.
- The AEDT initially replaced the Noise Integrated Routing System (NIRS) that was used for the noise analysis of large regional study areas that included multiple airports. AEDT has subsequently also replaced the Integrated Noise Model (INM) and the Emissions and Dispersion Modeling System (EDMS).
Records retention must be in accordance with the appropriate paragraph(s) in FAA Order 1350.15, Records Organization, Transfer, and Destruction Standards.
Although chapter 10 of FAA Order 1350.15 contains Air Traffic-specific information, guidance for retention of environmental documentation is contained in that portion of the order specific to the Airports Division.
- Environmental record−keeping should receive special attention at the field facility level. If an action requires preparation of an EA or an EIS, the Service Center Environmental Specialist must maintain an Administrative File for every proposed action. The Administrative File is important in the environmental process because it is a compilation of all the information relied upon by FAA in the decision−making process.
- Since some environmental projects may extend over several years, the Administrative File becomes a history of events. In the event of a legal challenge, the Administrative File will be used to develop the Administrative Record. The Administrative Record will be reviewed by the U.S. Court of Appeals to determine if the FAA complied with environmental requirements. The data and documentation contained in the File can also be used as the starting point for any follow-on environmental studies.
- Field facility personnel must consult with their Service Center Environmental Specialist to obtain guidance on what should or should not become part of the Administrative File. Regional counsel or AGC-620, as appropriate, should also be consulted on this. Federal court rules provide that when an FAA action is challenged in court, the agency has 40 days to compile the Administrative Record, make necessary copies, and file an index to the Record with the court. Therefore, it is preferable to begin development of the Administrative Record by maintaining an accurate Administrative File from the earliest stages of a project, instead of waiting until a lawsuit is filed.