3e. DAFF 813 327733 Flightline Drainage Correction redacted_Redacted.pdf

DAFF 813 # 327733

REQUEST FOR ENVIRONMENTAL IMPACT ANALYSIS

INSTRUCTIONS: Section I to be completed by Proponent; Sections II and III to be completed by Environmental Planning Function.

Section IV available as continuation space. Add separate sheets as necessary and reference appropriate item number(s).

SECTION I. PROPONENT INFORMATION

1. TO (Environmental Planning Function) 2. FROM (Proponent Organization and functional address symbol) 2a. TELEPHONE NO.

AFMC/A4C GS-11 Jonathan Garner

78 CEG/CENMP 468-7409

3. TITLE OF PROPOSED ACTION

Address stormwater drainage flume on southeast side of Robins AFB flightline, Facility 8700

4. PURPOSE AND NEED FOR ACTION (Problem Statement: Define the problem that needs a solution & outline goals that meet the solution.)

a. Identify the Proposed Action (Break out into concise discussion).

(see attached)

b. State the purpose of this action.

(see attached)

c. State the need for this action.

(see attached)

5. DESCRIPTION OF ACTION AND ALTERNATIVES (DOPAA) (Provide sufficient details for evaluation of the total action. Example questions to consider: What other alternatives have been considered (include the no action alternative)? What alternatives were eliminated from consideration and why? Within this scope of the proposal, is there a construction action and what is its timing? What is the project location (Attach map(s)/diagram(s)) showing project area)? What are additional project requirements, for example, construction and site preparation (include approx. area of ground to be disturbed); laydown yard or storage area resulting in groundwork required; soil borings/sampling/potholing during the design phase (separate dig permit will be required); detailed operational activities; and equipment/material list. Will the project require utilities and if so, how will those utilities be provided to the facility? Any additional details related to the Description of the Proposed Action and Alternatives.

(see attached)

6. PROPONENT APPROVAL (Name and Grade) 6a. SIGNATURE 6b. DATE

SECTION II – PRELIMINARY ENVIRONMENTAL SURVEY (Check appropriate box and describe potential environmental affects including cumulative effects) (+=positive effect; 0=no effect; - = adverse effect; U=unknown effect) + 0 - U

1. AIR INSTALLATION COMPATIBLE USE ZONE/LAND USE (Noise, accident potential, encroachment, etc.) X

2. AIR QUALITY (Emissions, attainment status, state implementation plan, etc.) X

3. WATER RESOURCES (Quality, quantity, source, etc.) X

4. SAFETY AND OCCUPATIONAL HEALTH (Asbestos/radiation/chemical exposure, explosives safety quantity distance, bird/wildlife aircraft hazard, etc.) X

5. HAZARDOUS MATERIALS/WASTE (Use/storage/generation, solid waste, etc.) X

6. BIOLOGICAL RESOURCES (Wetlands/floodplains, threatened or endangered species, etc.) X

7. CULTURAL RESOURCES (Native American burial sites, archaeological, historical, etc.) X

8. GEOLOGY AND SOILS (Topography, minerals, geothermal, seismicity, etc.) X

9. SOCIOECONOMIC (Employment/population projections, school and local fiscal impacts, etc.) X

10. INSTALLATION RESTORATION PROGRAM (Per- and Polyfluoroalkyl Substances & other contaminants in soil and groundwater) X

11. OTHER (Potential impacts not addressed above.) X

SECTION III – ENVIRONMENTAL ANALYSIS DETERMINATION

1.

X PROPOSED ACTION QUALIFIES FOR CATEGORICAL EXCLUSION (CATEX) # DoW A93-11; OR

PROPOSED ACTION DOES NOT QUALIFY FOR A CATEX; FURTHER ENVIRONMENTAL ANALYSIS IS REQUIRED.

2. REMARKS

CATEX nomenclature follows DOW NEPA Implementing Procedures updated April 30, 2026 (see attached)

3. ENVIRONMENTAL PLANNING FUNCTION CERTIFICATION

(Name and Grade)

3a. SIGNATURE 3b. DATE

Ronald J. Onderko, P.E., NH-4 AFMC Command Senior Civil Engineer

SECTION IV – Continuation of Specific Topics (Continue discussion from Sections I & II) (See attached)

DAF FORM 813, 20250903 Prescribing Directive: DAFI 32-1015

DEREK A GRIMSLEY, P.E. / NH03 Derek A. Grimsley Digitally signed by

GRIMSLEY.DEREK.ANTHONY.1591143170

Date: 2026.06.16 09:52:28 -04'00' 16 Jun 2026

Section I: Proponent Information

4. Purpose and Need for Action 4a. Identify the Proposed Action Robins Air Force Base (RAFB or Base) is in central Georgia, approximately 18 miles south of Macon, Georgia, and adjacent to the eastern city limits of the city of Warner Robins in Houston County (see Figure 1). Its western boundary runs parallel and adjacent to Georgia State Road 247. The Base is in the Middle Georgia Region.

Robins AFB is the home of the 78th Air Base Wing (78 ABW) and its 54 mission partners. The 78 ABW includes the 78th Civil Engineer Group (78 CEG) and 78 Operations Support Squadron (78 OSS). The 78 CEG is responsible for providing, operating, maintaining, restoring, and protecting the managed assets of the Robins infrastructure and facilities. This includes environmental stewardship, real property management, and space management, as well as facility maintenance and repair in-house and by contract, fire emergency services, and readiness and emergency management services.

Figure 1: Left - Robins AFB Vicinity Within Georgia. Right - Robins AFB (AFGIMS).

The 78 CEG works closely with the 78 OSS and other organizations to support the safety of flight operations on Robins AFB. Part of this effort involves reducing risks associated with flying, specifically through the Bird/Wildlife-Aircraft Strike Hazard (BASH) Plan and related working group efforts. BASH is designed to manage airfield habitat, bird control, removal of other wildlife, and bird dispersal activities.

One focus area of the BASH program is minimizing standing water on the flightline. Proper stormwater system design and maintenance is essential for success in that focus area.

The stormwater drainage on the southeast end of the flightline is in poor condition, leading to ponding and excessive vegetative growth (see Figure 2 and Figure 3).

Figure 2: Drainage Features at Southeast End of Runway 15-33. Open drainage and culverts in pink line, and underground gravity lines in dashed purple line. (AFGIMS).

Figure 3: Excessive Vegetation Along Open Drainage (AFGIMS)

The Proposed Action would involve removing overgrown vegetation in the drainage area and repairing the existing channel by replacing the existing drainage channel with a new concrete channel, also known as a flume, to convey stormwater away from the flightline.

4b. State the purpose of this action.

The Purpose of the Proposed Action is to correct drainage flow at the southeast end of the Robins runway to reduce vegetation overgrowth and wildlife in accordance with Department of the Air Force Instruction (DAFI) 91-212, Bird/Wildlife Aircraft Strike Hazard Management Plan.

4c. State the need for this action.

The Need for the Proposed Action is the excessive ponding and/or flooding of water within the area that allows vegetation growth and attracts wildlife within the area of the Robins flightline.

5. Description of Proposed Action and Alternatives

5.1 Proposed Action

The flume would be approximately 2,000 ft long and would be designed in the same general path as the existing drainage line while maintaining a buffer of at least 20 feet from the nearby landfill site (see Figure 4). Total disturbed area is estimated at 6.84 acres. This area would be cleared, grubbed, and dewatered as needed. Timing would be adjusted to minimize expected dewatering.

Figure 4: Existing Site Conditions including Landfill #2 in Crosshatch (modified excerpt from sheet C-100 of the Phase IV Corrected Design Drawings). Site Area 6 includes the original locations for the stockpile and laydown areas.

Figure 5: Overall Project Site with Updated Stockpile and Laydown Areas The proposed design would include check dams to narrow the channel and eliminate ponding and associated elevated BASH risk. This action would also improve the maintainability of the area. The bottom of the south end of the channel would be adjusted so that it is below the bottom of the road culverts. The concrete flume would begin at the nearby discharge point for stormwater piping. The existing grade would be grass. A concrete pad at the end of the channel would transition water to the two existing 60” culverts. To accommodate the 100-year storm discharge, two additional 60” culverts would be installed by the existing culverts.

Construction would be phased, with each phase section being no more than 100 feet in length. Methods like diversion channels, bypass pumping, and overall project timing (focusing on the drier months) would be used to prevent construction contamination downstream. Work would be done in the Runway Clear Zone; project would comply with UFC 3-260-01, Airfield and Heliport Planning and Design and UFC 3- 260-02, Pavement Design for Airfields. The flume would be designed to support maintenance equipment.

For example, the edge would be designed to be flush with the exterior grade to allow mower overlap (see Figure 6). As the existing soil is too weak to adequately support the structure, select stone (approximately 8,200 compacted cubic yards) and soil (approximately 5,811 CYs) backfill with separation geofabric would be utilized with two layers of geogrid to increase bearing capacity. Approximately 2,705 loose cubic yards (LCY) of debris would be hauled off-site. Approximately 88 CY of rip-rap would be used for slope protection. Approximately 188 CY of topsoil would be stripped and stockpiled.

Figure 6: Typical Channel Cross Section. See sheet C-501 of the 100% corrected design drawings.

The renovation of this drainage area would require a stockpile area (approximately 20,000 square feet, SF) and a laydown area (approximately 15,000 SF). Estimated locations and dimensions for these areas based flightline compatibility, floodplain and wetland avoidance, and restoration program asset avoidance is shown in Figure 7. The airfield would continue in full uninterrupted operation while construction occurs.

Figure 7: Updated Approximate Stockpile and Laydown Area Locations. Restoration assets in blue.

existing 75 Day-Night Level (DNL) and the 85 DNL (see C-130 Campus EA §3.2.1.1 for definitions, incorporated by reference).

Figure 8: Land Use Zones with Approximate Overlay of Notable Project Elements from Figure 5 Proposed Action Construction activities are anticipated to last approximately eight months (see sheet C-220 of the 100% Corrected Design Drawings). The temporary increase in noise from construction activities would be negligibly adverse relative to the existing environment dominated by aircraft noise as well as maintenance-related engine runs, etc. As the adverse noise impact would be negligible and short term, there would be no potential for contribution to a substantial reasonably foreseeable adverse noise impact.

No sensitive receptors are within the area of effect for the flightline. There would be no change in facility or surrounding land use. The area would continue to be part of the airfield and would support stormwater drainage needs. No changes in land use, airspace, or potential encroachment would be involved, that matches the nature of the Proposed Action in the C-130 Campus EA (see C-130 Campus EA §3.1).

Best Management Practices (BMPs) Construction will occur during normal government working hours (0700-1630 hours, Monday – Friday) with limited possible exceptions.

Conclusion (-) Based on the foregoing considerations, the Proposed Action would have no impact on land use and only a negligible short-term adverse impact on noise.

2. Air Quality Existing Conditions The Proposed Action would occur in Houston County, Georgia, that is in attainment for all criteria pollutants (see C-130 Campus EA §3.4.1 for definitions and §3.4.2 for more information on existing conditions). Therefore, a conformity determination under the Clean Air Act is not required. Robins AFB maintains a Title V operating permit.

GHG Relative Significance Assessment: The GHG emissions for this individual action are relatively negligible when compared to the sum of all actions at levels such as the state and national levels.

Compared to the CY24 Robins AFB reportable GHG emissions (49,979.8 mtons CO2e), this action would still be negligible (0.25%).

Best Management Practices (BMPs) No new air permits or air permit modifications would be needed. Short-term impacts would be minimized by BMPs, including but not limited to various methods of dust control (see sheet C-222 of the Phase IV Corrected Design Drawings). Dust control methods may include but are not limited to stabilizing disturbed areas with mulch or vegetative cover, irrigation, and barriers.

Conclusion (-) The Proposed Action would have short-term less than significant adverse impacts on air quality due to construction. These impacts would be minimized through the use of applicable BMPs.

3. Water Quality Existing Conditions Robins AFB lies in the Middle Ocmulgee Region, receives 40-52 inches of rain per year, and has an abundant groundwater supply from the Cretaceous Aquifer, approximately 400-500 ft below the ground surface (see C-130 Campus EA §3.5.1 for more details). The Base contains lakes, creeks, floodplains, and wetlands (including jurisdictional, see the Biological Resources section for floodplain and wetland discussion). Stormwater on Base is managed in accordance with the Base Stormwater Pollution Prevention Plan (SWPPP), discussed in §3.5.1.2 of the C-130 Campus EA. The Base maintains several National Pollution Discharge Elimination System (NPDES) permits for wastewater, stormwater, construction, and small municipal separate storm sewer systems at military facilities.

The Proposed Action area is within Drainage Area 1 (see Figure 9). This area is southeast of the drainage areas affected by the C-130 Campus that were also along the flightline. Runoff and groundwater flow toward the southeast, reflected in the NPDES sampling location 004.

Figure 9: Drainage Area 1. Modified excerpt from page 521 of the 2023 SWPPP with Approximate Overlay of Notable Project Elements from Figure 5.

Runoff in the Proposed Action area drains southeast to Horse Creek, a surface water in good condition according to US Environmental Protection Agency’s (EPA’s) My Waterway (see Figure 10).

Figure 10: Nearby Waterways (modified from https://mywaterway.epa.gov/) with Approximate Overlay of Notable Project Elements from Figure 5.

Proposed Action The Proposed Action would renovate an existing drainage area that is currently inadequate for existing and projected stormwater drainage requirements. Renovation work would cause less than significant short-term adverse impacts to surface waters, namely Horse Creek, due to construction runoff.

Stormwater management in the area would be improved and would continue to be implemented in accordance with the SWPPP. There would be no impacts to wastewater generation/treatment or to available groundwater or groundwater quality.

BMPs and Other Programmatic Requirements Ensure no unauthorized pollutants enter Robins stormwater and/or waste stream pre, during, or post construction. During construction, follow all applicable Best Management Practices (BMPs) found in the Georgia Erosion and Sediment Control Manual (https://gaswcc.georgia.gov/urban-erosion-sediment-control/technical-guidance). This project would disturb greater than 1 acre and would require coverage under the National Pollutant Discharge Elimination System (NPDES) GA100001 Construction General Permit (CGP). The Land Disturbing Activity (LDA) Permit is obtained through the Environmental Management Office and Houston County. The permit application would be drafted by the contractor using a template provided by the Robins AFB Stormwater Program Manager. The contractor shall submit all permit-required documents for review to the Robins AFB Environmental Management Office. The contractor is responsible for all fees. All documents for Houston County will be coordinated through the Stormwater Program Manager. Houston County will also need a copy of the Notice of Intent (NOI), a paper copy of the Erosion, Sedimentation, and Pollution Control (ES&PC) Plan on 11” x 17” tabloid paper and an electronic copy of the ES&PC Pan. Disturbed area includes disturbance of soils associated with clearing, grading, excavating, filling of land, land disturbed laydown areas, or other similar activities, that may result in soil erosion. Additionally, the project would need to comply with and be designed using Better Site Design Practices as identified in the Georgia Stormwater Management Manual, available at www.georgiastormwater.com.

The contractor would also be responsible for applying for a 25-foot vegetative buffer encroachment variance. All draft application materials must be submitted to the Robins AFB Environmental Management Office for review prior to application. All responses from external agencies must be provided to the Robins AFB Environmental Management Office.

Specific BMPs would include silt fencing (3’ high, approximately 5,500 linear feet (LF), based on the 100% corrected cost estimate) and straw-filled inlet baffles (approximately 800 LF). A construction entrance, concrete washdown area, and construction road stabilization would limit the spread of construction site materials outside of their intended areas.

Impact of Weather on Proposed Action’s Environment Per US Environmental Protection Agency (EPA), the severity of both inland flooding and droughts in Georgia is expected to increase over time. According to the Department of Defense (DoD), the most extreme weather/wildfire damage for Houston County, GA from 2000-2021 was from wind damage followed by hail . The highest ranked weather hazard for the 2050- and 2085-higher emissions scenarios is drought because of the projected increase in mean annual runoff.

Impact of Weather on Proposed Action The Proposed Action would improve management of existing and expected stormwater runoff and would not increase water consumption. Therefore, projected local weather conditions would not affect the Proposed Action.

Conclusion (-) The Proposed Action would have a short-term, less than significant adverse impact to Water Resources (surface waters) at Robins AFB because of land disturbing construction activities (excavation, grading). These impacts would be minimized through the use of appropriate BMPs as well as adherence to the Clean Water Act and applicable NPDES construction permits. No change to stormwater volumes or available groundwater would result due to the Proposed Action.

4. Safety and Occupational Health Existing Conditions The Base maintains a BASH program to protect airfield flying operations by effectively managing bird/wildlife strike risks. Part of this management involves reducing the appeal of the flightline area to wildlife. By reducing larger vegetation and ponding, wildlife such as birds are less likely to roam into the area. Due to inadequate drainage, the Proposed Action area currently poses safety hazards to the flightline due to ponding and wildlife appeal. This area is not in an explosive safety quantity area and no unexploded ordnances are expected in the area.

Proposed Action The Proposed Action would eliminate the ponding issues and reduce wildlife attraction on the flightline, aligning with the BASH Plan. It would not increase the risks of explosion.

BMPs and Other Programmatic Requirements As discussed in §3.6.2 of the C-130 Campus EA, contractors on Base are required to have a health and safety plan and are solely responsible for their compliance with Occupational Safety and Health Administration (OSHA) standards.

Conclusion (+) The Proposed Action would have a positive impact on Occupational Safety because it would reduce BASH risk. This effect was also discussed in §3.8.3.2 of the C-130 Campus EA that anticipated reduced BASH risk due to ensuring the adequacy stormwater drainage systems. If no action is taken, flightline safety conditions are expected to worsen over time as vegetation continues to develop and ponding increases.

5. Hazardous Materials/Waste Hazardous Materials Existing Conditions Hazardous materials (HM) are managed under the Base’s Hazardous Materials Management Plan (HMMP). As discussed in §3.7.2.1 of the C-130 Campus EA, the Base uses approximately 2,500 tons of HM a year, most of which is used by the Warner Robins Air Logistics Complex (WR-ALC), one of three Air Force depots. Existing drainage flume maintenance uses little to no HM.

Proposed Action The Proposed Action would use little to no short-term HM for replacement of the drainage flume.

Depending on design/construction details, some welding gases, marking paint, and/or sealants may be needed. There would be no long-term change in HM usage because there would be no associated operational changes. No new or different hazardous materials would be needed.

BMPs If any HM are needed, they will be approved prior to bringing them on Base. All HM will be tracked in Enterprise Environmental Safety & Occupational Health-Management Information System (EESOH-MIS).

As discussed in §3.7.1.1 of the C-130 Campus EA, spent HM would be reused or recycled whenever possible.

Conclusion (-) The Proposed Action would have little to no short-term adverse impacts on the environment regarding hazardous materials because construction and demolition activities may require the use of hazardous materials. These impacts would be minimal because the quantity of products containing hazardous materials used would be minimal and their use would be of short duration.

Hazardous Waste Existing Conditions Hazardous waste (HW, specifically Resource Conservation and Recovery Act (RCRA) HW, see §3.7.1.2 of the C-130 Campus EA for definition) is managed under the Base’s Hazardous Waste Management Plan (HWMP). As noted in §3.7.2.2 of the C-130 Campus EA, the Base generates approximately 1,400 tons of HW a year and is considered a large quantity HW generator. Existing drainage flume maintenance generates little to no HW.

Proposed Action The Proposed Action would generate little to no short-term HW for replacement of the drainage flume.

Depending on design/construction details, some welding gases, marking paint, and/or sealants may be needed, which may result in negligible amounts of HW. There would be no long-term change in HW generation because there would be no associated operational changes. See Block 14 for soil contamination discussion. No new HW permit would be needed, nor would changes to the existing permit be needed. There would be no increase in risk of release of hazardous materials/waste beyond any minimal quantities in use for temporary construction/renovation activities.

BMPs and Other Programmatic Requirements Any potentially RCRA-hazardous wastes expected to be generated from the project and destined for disposal will be evaluated by 78 CEG/CEIER to determine waste sampling and handling requirements prior to start of work, in accordance with the FY24 HWMP (see §7.2 and §7.5) and Section 01560 Environmental Requirements §2.2.2.a. Due to the preliminary testing, no additional testing will be needed for RCRA HW unless waste conditions during the project exceed what was expected and appear to be potentially hazardous.

Any unused hazardous materials brought on-Base for use by contractors will be removed from Base as the contractors’ property, i.e. do not dispose of the material on-Base or turn it over to Base personnel. All hazardous waste, universal waste, used oil, and reclaimed fuel disposal will be coordinated with 78 CEG/CEIE. Containers accumulating hazardous waste will be managed under either the satellite or 90-day rules. Enough area will be allocated for placement of containers needed for accumulation, storage, and movement of containers (pickup and replacement of filled roll-off containers may take up to 8 (eight) working days).

Conclusion (-) The Proposed Action would have a little to no adverse impact regarding hazardous waste because any hazardous waste generation due to the proposed action would be managed and disposed of in a manner consistent with the most current Robins AFB Hazardous Waste Management Plan (HWMP), available on eDASH and by request. Based on the nature of the work, little to no HW is expected.

Solid Waste Existing Conditions Robins AFB works to reduce, reuse, and recycle waste to the extent practicable. This goal is reflected in the Integrated Solid Waste Management Plan (ISWMP) and the Qualified Recycling Program (QRP).

Current diversion goals (from the 2025 ISWMP) are 50% for non-hazardous waste as well as construction and demolition (C&D) waste. The Base is aiming for 75% diversion by 2030. At the time the C-130 Campus EA was written, the 2022 ISWMP had a goal of 40% for municipal solid waste (MSW) and 60% for C&D by 2025 (see §3.7.2.3 of the C-130 Campus EA). These goals show a tendency toward greater stringency over time. As of FY24, the actual non C&D diversion rate was 38.5% and the C&D diversion rate was 89.6%. These actual diversion rates exhibit notably variability, with the non C&D rate ranging from 24.1% to 47.8% from FY13 to FY24 and the C&D rate ranging from 2% to 89.6% in the same period.

Diversion methods are discussed in section 7.3 of the 2025 ISWMP and include transporting wood waste to the local Houston County landfill for mulching and reusing wood pallets when feasible, Proposed Action The Proposed Action would generate solid waste comprised primarily of vegetative waste (from clearing and grubbing the drainage area), concrete (C&D waste from removal of existing concrete channel), used polypropylene silt fencing (5,500 LF) and inlet baffles (800 LF), and soil (cut and fill replacement of structural inadequate soils). The 100% corrected cost estimate anticipated approximately 2,705 loose cubic yards (LCY) would be hauled off site. No new HW permit would be needed, nor would changes to the existing permit be needed.

BMPs and Other Programmatic Requirements Solid waste will be handled, managed, and disposed/recycled of in accordance with Section 01560 Environmental Requirements and the Robins AFB Integrated Solid Waste Management Plan, available on eDASH and by request. As noted in Section 01560, “All persons engaged in solid waste handling, including solid waste collection and transportation, or operations of solid waste handling facilities or disposal sites, shall have a solid waste handling permit or permit by rule letter.” All personnel, including contractors, are encouraged to reduce, reuse, and recycle waste to the extent practicable. The contract for the Proposed Action is expected to require the construction contractor to divert minimum 60% of non-hazardous C&D waste from landfills. Solid waste generated would be handled and disposed of in a manner to prevent pollution of the surrounding area.

Conclusion (-) This Proposed Action would have a short-term, less than significant adverse impact on the environment regarding solid waste because the repair/modification of the drainage system would temporarily generate solid waste. Based on the expected contract mandated diversion rate, with waste not expected to be hazardous based on preliminary sampling, at least 1,623 LCY would be diverted and up to 1,082 LCY would be sent to the landfill. Contractors hired for the project would be required to have a solid waste handling permit or permit by rule letter.

Toxics Existing Conditions The Proposed Action Area does not involve any buildings and is thus not expected to involve any toxic materials managed under the Toxic Substances Control Act (TSCA), which for Robins AFB primarily addresses asbestos, lead-based paint, and polychlorinated biphenyls (PCBs). The C-130 Campus EA removed toxic materials from focused consideration due to similar circumstances (see § 3.1).

Proposed Action The Proposed Action would involve clearing out a heavily vegetated drainage flume and replacing it with a more adequately designed drainage channel. No buildings would be demolished as part of the action.

No new or different toxic materials would be needed.

BMPs and Other Programmatic Requirements Any waste to be disposed of off Base is characterized and coordinated with 78 CEG/CEIER in accordance with Base policies. In this case, testing has been done as part of the design effort and indicated no RCRA HW.

Conclusion

(0) This Proposed Action would have no effect on the environment regarding toxic materials/waste because no toxic materials/waste are expected from the project.

Tanks Existing Conditions There are no tanks or fuel piping within the project area. There are fuel tanks west of the project area within a well-defined and protected location. An installation pipeline also runs approximately 250 ft to the northwest of the site area.

Proposed Action The Proposed Action of replacing a drainage flume would not affect any surrounding tanks or fuel/oil assets. The Proposed Action would also not add any such features to the area.

Conclusion

(0) The Proposed Action would have no impact on the environment in relation to Aboveground Storage Tanks (AST), Underground Storage Tanks (UST), or Oil Water Separators (OWS) because there are no such features in the proposed project area, and no tanks or oil water separators are being installed.

Spills Existing Conditions There are no existing sources of oil/fuel contamination within the Proposed Action area.

Proposed Action The Proposed Action would not permanently install any potential sources of oil/fuel in the project area.

BMPs and Other Programmatic Requirements Contractor must follow applicable Base plans, policies, and procedures, including the Robins Spill Prevention, Control, and Countermeasures (SPCC) Plan and 40 CFR § 112.20.

Conclusion

(0) This Proposed Action does not present an impact regarding the Spill Program, because in accordance with 40 CFR § 112.20, this project does not pose substantial harm to the environment by discharging oil into or on navigable waters or adjoining shorelines.

6. Biological Resources Existing Conditions The Base lies south of the Fall Line, east of the Ocmulgee River, and within the Sand Hills portion of the Southeastern Plains Ecoregion. The Proposed Action area includes both jurisdictional wetlands (see Figure 11) and the 100-year floodplain (see Figure 12). The drainage flume to be renovated, a manmade drainage feature, was determined to be a Palustrine Emergent Persistent Excavated Wetland (PEM1x) with the section passing under Richard Ray Blvd being a Riverine Intermittent Streambed Artificial Substrate Wetland during the 2025 wetland delineation. The drainage area has an ordinary high water mark. Much of this wetland area was previously addressed in an Environmental Assessment in 2009 regarding the Clear Zone. The efforts analyzed in the 2009 EA included the purchase of wetland credits to compensate for filling 19.5 acres of wetlands. Part of the area has regained wetland characteristics.

This area was surveyed for threatened and endangered species as part of basewide survey efforts, discussed in United States Fish and Wildlife Service (USFWS) consultation documentation (C-130 Campus EA Appendix C, Attachment 3) as well as the Integrated Natural Resources Management Plant (INRMP). The same species of concern were identified and considered for this project as for the C-130 Campus EA (see C-130 Campus EA section 3.8.2.3 for existing conditions). The American alligator, that is considered threatened due to similarities of appearance to the federally threatened American crocodile, has been sited close to the Proposed Action area and may occur in the area due to flooded and vegetated conditions (see §3.8.3.2 of the C-130 Campus EA). The project location does not otherwise contain protected biological resources, nor critical habitat for endangered species, or any other protected flora or fauna species.

Figure 11: Wetlands in Project Area (2025 Wetland Delineation Report) with Approximate Overlay of Notable Project Elements from Figure 5.

Figure 12: 100-Year Floodplain in Project Area (Colorado State University Data) with Approximate Overlay of Notable Project Elements from Figure 5

The manmade drainage feature would be repaired/realigned, causing negligible adverse impacts on wetland features in the area. Turf grass would be removed from the adjusted drainage path, constituting a less than significant adverse impact on vegetation. Approximately 1.8 acres of the 100-year floodplain (about 1.1 acres less than in the C-130 Campus EA, see §3.8.3.2) and 1 acre of wetlands would be disturbed during construction. The 100-year floodplain characteristics would be unaffected. The changes to the drainage channel would support improved maintainability, which would reduce the appeal for wildlife in the vicinity. The reduction in appeal would support improved safety for personnel, aircraft, and wildlife.

BMPs and Other Programmatic Requirements The Proposed would require application for a NWP to meet Clean Water Act, Section 404 requirements regarding the discharge of dredged or fill material into waters of the United States (WOTUS). Based on preliminary discussion with the USACE Regulatory Division, the action would likely be best authorized under NWP No.3 (NWP 3 ) – Maintenance. The NWP application would be completed and submitted via the USACE Regulatory Request System (RRS, https://rrs.usace.army.mil/rrs). USACE processing time for NWPs is typically 30-45 days. The contractor would be responsible for preparing and submitting the NWP application. The contractor would also be responsible for purchasing wetland credits, if deemed necessary. The draft submission must be sent to the Robins AFB Environmental Management Office (Attn: Stormwater and Natural Resources) for review. All correspondence from external entities must also be provided to the Robins AFB Environmental Management Office.

Aquatic resources are to be protected with temporary erosion control devices, as applicable (see Water Quality BMPs for more details).

Use of appropriate BMPs would avoid potential adverse impacts on the American alligator. Specifically, if an American alligator is found in the Proposed Action area during project execution, project staff will contact Natural Resources (78 CEG/CEIEC) for guidance and support in handling and potentially relocating the alligator, in accordance with existing Base procedures (as was also noted in the C-130 Campus §3.8.3.2).

Per GA Department of Natural Resources (GA DNR) Wildlife Resources guidance, a survey for roosting birds and bats in the culvert should be performed before work is initiated. Results to be provided to GA DNR via the Natural Resources Program Manager. If tricolored bats or bat signs are found in the culvert, Robins AFB and contractor staff would adhere to USFWS-wide northern long-eared bat and tricolored bat programmatic agreement guidance, dated 15 Apr 2025, as applicable and to the extent practical (https://www.fws.gov/library/collections/consultation-technical-assistance-development-projects). If the tricolored bat is listed as endangered before this project begins, the Natural Resources Program Manager will resume consultation to ensure all appropriate precautions are taken. Project staff will contact the Natural Resources Program Manager for guidance. Specific considerations would include avoiding initiating disturbance during the tricolored bats winter torpor period (15 December – 15 February) and during the summer non-volant pup season (1 May – 15 July).

Conclusion (-) Overall, the Department of the Air Force determined the Proposed Action may affect but is not likely to adversely affect federally listed species on Robins AFB. The USFWS concurred with this determination on 12 Nov 2024 (see Attachment 3). For these reasons there would be only less than significant adverse impacts to biological resources associated with this Proposed Action.

7. Cultural Resources Existing Conditions As discussed in the Robins AFB Comprehensive Programmatic Agreement (Comp PA), which was most recently signed on 9 Sep 2025 when it was extended for one year while updates are finalized, all disturbed/developed areas on Base have been surveyed for cultural resources. There are no cultural resources in the area of potential effect (APE). In accordance with the Comp PA §4.4, as also discussed in the C-130 Campus EA §3.3.1.2, construction and other land clearing activities for sites that have been surveyed and determined not to contain National Register of Historic Places (NRHP) eligible sites qualify awarded in contracts in FY24. No children live on or go to the flightline area.

The Proposed Action would include both a design and a construction contract. Both of these contracts would be temporary. The design contract was already awarded in 2023 and completed in 2024 for

Construction cost was estimated at No long-term changes in employment would result because of the Proposed Action. No children would be affected by Proposed Action.

Conclusion (+) The Proposed Action would have a short-term positive socioeconomic impact due to construction activities (cost of labor/materials – approximately . No long term socioeconomic changes are anticipated.

10. Environmental Restoration Program (ERP) Existing Conditions The Proposed Action would occur in the immediate vicinity of an active ERP site, Landfill #2 (Solid Waste Management Unit (SWMU 2, LF002, see Figure 5 and Figure 13). Landfill #2 includes approximately 22 acres and was operated from 1951 to 1963 until it was closed and covered with clayey sand. Land use controls for this site include a restriction on any excavation within the site area.

Figure 13: Active ERP Sites in Proposed Action Vicinity (Modified excerpt from page 209, volume 1, of the 2022-2023 Basewide Corrective Action Plan Progress Report) with Approximate Semi- Transparent Overlay of Notable Project Elements from Figure 5.

Part of the Proposed Action area would also occur within the extent of contamination for SWMU 20, the Greater Base Industrial Area (GBIA) chlorinated solvent groundwater plume. The elevation of the plume is at approximately 240 ft above mean sea level (AMSL) in the drainage area (estimated using figure information between wells OT20EW8 and OT20EW2).

Figure 14: SWMU 20 Cross-Section (modified excerpt of Figure 8-2 from volume 2 of the 2022-2023 Basewide Corrective Action Plan Progress Report) Based on soil testing during design development, soil contamination was present (lead, several polynuclear aromatic hydrocarbons (PAHs)) but was not extensive enough to warrant any soil waste to be considered RCRA-HW. The results for analysis of volatile organic compounds (VOCs), semi-volatile organic compounds (SVOCs), pesticides, paint filter test, corrosivity, ignitability, mercury, and RCRA metals were compared to the EPA regulatory limits for characteristics defining a hazardous waste in accordance with 40 CFR § 261.24. Based on those comparisons, toxicity characteristic leaching procedure (TCLP) lead was the only analyte detected above the laboratory reporting limit. The detected lead concentrations (0.119 milligrams/liter (mg/L) and 0.763 mg/L) were well below the TCLP limit of 5 mg/L. All other compounds analyzed using TCLP were below applicable laboratory reporting limits. Based on the results from the range of testing performed, the soil does not exhibit hazardous waste characteristics.

Aqueous Film Forming Foam (AFFF) sites are still under investigation at Robins AFB. The boundaries of AFFF contamination are not yet well known. AFFF is also not considered RCRA-HW. The available sample data from the final site inspections report in 2018 was considered. This information was also discussed to an extent in §3.9.2.1 of the C-130 Campus EA. Based on the preliminary data, surface water flow, and groundwater flow, contamination of the Proposed Action area with PFAS from these sites is not expected.

Proposed Action The Proposed Action would involve excavation in close proximity to a closed landfill (LF0002) and the SWMU 20 groundwater plume. The groundwater plume lies approximately 10 ft below the current trench.

Cut and fill excavation is not expected to reach the plume. AFFF, particularly PFOA and PFOS, may be present within the cut material, which would be removed from Base. The C-130 Campus EA predated design for its subject projects, so a 10% soil replacement rate was used (see §3.9.3.2 of the C-130 Campus EA). For the currently proposed project, design has already been completed, allowing more precise estimates for soil replacement and overall project waste (2,705 LCY removed, 5,811 CY of fill).

Soil fill material would come from off Base.

BMPs and Other Programmatic Requirements Landfill #2 cannot be penetrated due to the existence of waste mass very close to the soil surface.

Ensure 20 ft buffer from landfill is maintained. The Base Remedial Program Manager (RPM) must be coordinated with to assure that the drainage project does not cross into the landfill surfaces. As noted in §3.9.2.1 of the C-130 Campus EA, ERP assets must be protected during projects. Any damage to ERP assets must be replaced at the project proponent’s expense. There are ERP groundwater monitoring wells in the area (see Figure 7). Access to these wells must be available at all times. Before the laydown and/or staging areas are used, coordinate with the Base RPM so the wells can be marked to ensure avoidance.

The proponent should have contingencies in place for disposal of any contaminated soils/media generated during excavation. Any potentially RCRA hazardous waste must be tested and test results must be provided to 78 CEG/CEIER, as discussed under Block 11, subsection Hazardous Waste. As the Proposed Action area is upgradient from AFFF contamination, testing for AFFF will not be required.

Conclusion (-) The proposed drainage improvements replacement should have a less than significant adverse impact regarding the Environmental Restoration Program because although there is potential to affect ERP assets, such impacts should be minimized if not entirely avoided by routing disturbance around ERP assets (wells) and the closed Landfill # 2 in the area. The SWMU 20 groundwater plume is not expected to be encountered. AFFF is not expected to be present.

Section III: Environmental Analysis Determination

1. CATEX Description (if any) A.II.11. “Actions similar to other actions which have been determined to have an insignificant impact in a similar setting as established in an EIS or an EA resulting in a FONSI. The EPF must document application of this CATEX on AF Form 813, specifically identifying the previous Air Force approved environmental document which provides the basis for this determination. (See TAB B)”

2. Remarks This action qualifies for categorical exclusion (CATEX) A.II.11 “Actions similar to other actions which have been determined to have an insignificant impact in a similar setting as established in an EIS [environmental impact statement] or an EA [environmental assessment] resulting in a FONSI [finding of no significant impact]. The EPF [environmental planning function] must document application of this CATEX on AF [Air Force] Form 813, specifically identifying the previous Air Force approved environmental document which provides the basis for this determination. (See TAB B) ”. Robins AFB analyzed similar actions in 2024 where stormwater drainage in vicinity of the Robins AFB flightline was modified documented within EA titled Development of a C-130 Campus (C-130 Campus EA). FONSI was signed by the Senior Command Civil Engineer at Air Force Materiel Command (AFMC) 25 Jan 2024. See attached continuation sheet.

The Proposed Action has no potential to impact groundwater or water supply, and thus no detailed coverage for these areas was deemed necessary.

The Proposed Action is similar both in the nature of the action itself as well as its setting to the stormwater utility work in C-130 Campus EA. Both actions would involve construction/renovation of stormwater features within the 100-yr floodplain of the Ocmulgee River and associated wetlands. Both actions address stormwater deficiencies on airfields by substantially renovating existing stormwater features to improve flow conditions. Both actions unavoidably occur in the 100-yr floodplain due to the nature of stormwater and the location of the airfields. Based on the physical location and similar activities to be conducted, the environmental analyses within the C-130 Campus EA are relevant and applicable and have been incorporated by reference. Therefore, the Proposed Action is sufficiently similar to the C- 130 Campus and CATEX A.II.11 applies. In addition, the public was provided with an opportunity to comment during the 2 November to 1 December 2024 public review period. No public comments were received.

Finding of No Practical Alternative. Based on the analysis contained here and within the C-130 Campus EA, and pursuant to Executive Orders 11988, Floodplain Management, and 11990, Protection of

Wetlands, I find there is no practicable alternative to repairing the flightline drainage with replacement within the Ocmulgee River 100-year floodplain and surrounding jurisdictional wetland areas, and that the Proposed Action includes all practicable measures to minimize harm to the environment. This analysis fulfills the requirements of NEPA, the DAF NEPA Implementing Procedures, as well as EO 11988, Floodplain Management, and EO 11990, Protection of Wetlands.

AIR CONFORMITY APPLICABILITY MODEL (ACAM) REPORT

RECORD OF AIR ANALYSIS (ROAA)

Attachment 1: ACAM ROAA

1. General Information: The Air Force’s Air Conformity Applicability Model (ACAM) was used to perform a net change in emissions analysis to assess the potential air quality impact/s associated with the action. The analysis was performed in accordance with the Air Force Manual 32-7002, Environmental Compliance and Pollution Prevention; the Environmental Impact Analysis Process (EIAP, DAF NEPA Implementing Procedures);

the General Conformity Rule (GCR, 40 CFR 93 Subpart B); and the USAF Air Quality Environmental Impact Analysis Process (EIAP) Guide. This report provides a summary of the ACAM analysis.

Report generated with ACAM version: 5.0.24a

a. Action Location:

Base: ROBINS AFB State: Georgia County(s): Houston Regulatory Area(s): NOT IN A REGULATORY AREA

b. Action Title: Address stormwater drainage flume on southeast side of Robins AFB flightline, Facility 8700

c. Project Number/s (if applicable): UHHZ160138

d. Projected Action Start Date: 1 / 2027

e. Action Description:

The Proposed Action would involve removing overgrown vegetation in the drainage area and repairing the drainage line via installation of a new concrete flume. The flume would be approximately 2,000 ft long and would be designed along the existing drainage line. The design would include check dams to narrow the channel and eliminate ponding and associated elevated BASH risk. This action would also improve the maintainability of the area. The bottom of the south end of the channel would be adjusted so that it is below the bottom of the road culverts. The concrete flume would begin at the nearby discharge point for stormwater piping. The existing grade would be grass. A concrete pad at the end of the channel would transition water to the existing culverts. The work would be done in the Runway Clear Zone; project would comply with UFC 3- 260-01, Airfield and Heliport Planning and Design and UFC 3-260-02, Pavement Design for Airfields. The flume would be designed to support maintenance equipment. For example, the edge would be designed to be flush with the exterior grade to allow mower overlap. See attached AF 813 for more details.

f. Point of Contact:

Name: Marissa Hartleb Title: NH-03 Organization: 78 CEG/CEIER Email: marissa.hartleb@us.af.mil Phone Number: (478) 222-2212

2. Air Impact Analysis: Based on the attainment status at the action location, the requirements of the GCR are:

applicable X not applicable

Total reasonably foreseeable net direct and indirect emissions associated with the action were estimated through ACAM on a calendar-year basis for the start of the action through achieving “steady state” (i.e., no net gain/loss in emission stabilized and the action is fully implemented) emissions. The ACAM analysis uses the latest and most accurate emission estimation techniques available; all algorithms, emission factors, and methodologies used are

ACAM GREENHOUSE GAS (GHG) REPORT

Attachment 2: ACAM GHG

1. General Information: The Air Force’s Air Conformity Applicability Model (ACAM) was used to perform a net change in emissions analysis to estimate GHG emissions associated with the action. The analysis was performed in accordance with the Air Force Manual 32-7002, Environmental Compliance and Pollution Prevention;

the Environmental Impact Analysis Process (EIAP, DAF Implementing Procedures); and the USAF Air Quality Environmental Impact Analysis Process (EIAP) Guide. This report provides a summary of the GHG emissions analysis.

Report generated with ACAM version: 5.0.24a

a. Action Location:

Base: ROBINS AFB State: Georgia County(s): Houston Regulatory Area(s): NOT IN A REGULATORY AREA

b. Action Title: Address stormwater drainage flume on southeast side of Robins AFB flightline, Facility 8700

c. Project Number/s (if applicable): UHHZ160138

d. Projected Action Start Date: 1 / 2027

e. Action Description:

The Proposed Action would involve removing overgrown vegetation in the drainage area and repairing the drainage line via installation of a new concrete flume. The flume would be approximately 2,000 ft long and would be designed along the existing drainage line. The design would include check dams to narrow the channel and eliminate ponding and associated elevated BASH risk. This action would also improve the maintainability of the area. The bottom of the south end of the channel would be adjusted so that it is below the bottom of the road culverts. The concrete flume would begin at the nearby discharge point for stormwater piping. The existing grade would be grass.