Attachment_0007_-_NEPA_CE_Enchanted_Pond_Outflow_System_Replacement.pdf

DOI-BLM-Eastern States-M034-2025-0001-CX

UNITED STATES DEPARTMENT OF THE INTERIOR

Bureau of Land Management

Northeastern States District

Lower Potomac Field Station

10406 Gunston Road

Lorton, VA 22079

CATEGORICAL EXCLUSION

A. BACKGROUND

Proposed Action Title/Type: Enchanted Pond Outflow System Replacement

Location of Proposed Action: Meadowood Special Recreation Management Area

Lease/Serial/Case File No (if any): DOI-BLM-Eastern States-M034-2025-0001-CX

Applicant: Bureau of Land Management

B. DESCRIPTION OF PROPOSED ACTION:

Enchanted Pond is located within the Meadowood Special Recreation Management Area

(SRMA) in Lorton, Virginia (Map, Attachment 1). The site hosts veteran and youth fishing events, outdoor education programs, and is open daily to the public for fishing and picnicking.

The Bureau of Land Management (BLM) proposes to replace the Enchanted Pond outflow system that is at risk of failure. The current outflow system is compromised; it is filled with silt, vegetation, and other natural material, which does not allow water to flow properly causing the pond to overflow into the surrounding meadow. The intake for the Enchanted Pond is currently clogged (Attachment 2), and water leaks underneath the outflow pipe (Attachment 3). These issues weaken the structural stability of the pond embankment. If this problem is not resolved, it may negatively affect areas both upstream and downstream of Enchanted Pond. The Proposed

Action is to ensure proper flow regulation and to prevent any future erosion issues associated with the deteriorated outflow system currently in place. The Proposed Action would improve habitat in the pond, improve water quality, and restore natural flows and aquatic organism passage.

To address the structural issues, the BLM proposes to remove the existing compromised corrugated outflow system by digging a 30-foot wide, 15-foot deep, and 80-foot long trench to remove the current pipe. The pond water level would be reduced but not completely drained during the outflow system removal. It may take approximately 90 days for nature to return the pond water to pre-drained level. The existing outflow system would be replaced with a new high-density polyethylene (HDPE) extruded outflow system pipe.

The outflow system replacement would involve the following actions:

• Before construction, signage would be posted about the temporary closure of the impoundment area and pond.

• Preparing the site for the removal and installation of the outflow pipe. Pre-excavation of the site may include vegetation removal and soil dug up where the existing pipe is located on the impoundment. Temporary store topsoil and excavated material from area would be located along the mowed area southwest of Enchanted Pond. This material would be used for backfilling.

• Diverting the existing water flow to the creek downstream from the pond to allow dry working conditions at the outflow location. Potential use of cofferdam (a temporary watertight enclosure) and pumping water downstream may be used to help dewater construction area.

• Dismantling and removing the existing outflow pipe without causing damage to the pond's embankment and ensuring the structural integrity of the pipe bedding and the surrounding soil before the installation of the new pipe.

• Installing a new HDPE outflow pipe that meets the pond’s flow requirements and is properly fitted to avoid future leaks or erosion.

• Re-establishing water flow through the new HDPE outflow pipe while ensuring proper functioning and no immediate erosion risks.

• Installing downstream water features (e.g., rocks weirs) at the end of the pipe along the stream to decrease erosion and increase habitat enhancement.

• Restoring the construction site to its original condition, with improved stability and erosion protection measures in place. The replanting of vegetation would implement erosion control.

The replacement of the Enchanted Pond outflow system would require the use of heavy equipment and machinery. The equipment would typically operate from on or near the pond embankment and already disturbed areas. Equipment that may be used, but not limited to, are an excavator, dump truck, skid steer, and front-end loader. All equipment would utilize the access road off Gunston Road and park next to the pond. Additionally, the soil moved would be put back on the new outflow system after the replacement occurs.

Required mitigating measures to minimize surface disturbance impacts during construction activities would include:

• Ground protection matting in high trafficked areas to minimize soil disturbance.

• Operations would not occur after a rainfall of 0.5 inches or more.

• Operations would not continue if any equipment sank into the ground more than 2 inches.

• The installation of sediment fence around the excavation area.

• Construction equipment must adhere to manufacturers’ guidance regarding fuel and maintenance schedule.

Funding for the project is proposed through the Great American Outdoors Act (GAOA) Legacy

Restoration Fund (LRF). The proposed activities at Enchanted Pond are planned to occur in 2025 to 2026. Construction work would be weather-dependent, commencing sometime during the winter months in northern Virginia (December-February) and take from 1 to 3 weeks to complete. Construction would take place in the winter months due to lower water levels to complete the project, less visitation disturbance, a reduction of spreading invasive species, and less wildlife disturbance.

The Proposed Action of replacing the outflow system would prevent the potential for a future catastrophic failure of the Enchanted Pond impoundment. Additional benefits of the project include improved management, access, and safety on public lands; increasing and enhancing the visitor experience; improving efficiencies for maintenance; and maintaining the ecological balance as Enchanted Pond is integral to the meadow ecosystem within Meadowood SRMA.

C. LAND USE PLAN CONFORMANCE

Land Use Plan Name: Meadowood Farm Planning Analysis/Environmental Assessment

Date Approved: March 2003

The Proposed Action is in conformance with the applicable LUP because it is clearly consistent with the following LUP decision(s) (objectives, terms, and conditions) even though it is not specifically provided for:

“Riparian/Wetland and Ponds: Increased land disturbance and recreational activities would require additional resource commitments and general project-by-project restrictions to protect riparian resources. Trail and facility construction would avoid RPAs or would be completed using boardwalks to avoid long-term impacts on riparian/wetland areas. Riparian habitat would improve as weed species would be controlled. All riparian/wetland protection and improvements would be conducted in accordance with

BMPs as mentioned in Chapter 2. Also, some riparian improvement projects would be implemented to speed riparian habitat recovery where needed.

Regular cooperative management of pond fisheries would be performed, which would assist in avoiding the ponds filling due to sedimentation and aquatic vegetation growth.”

(p. 4-22).

D. COMPLIANCE WITH NEPA

The Proposed Action is categorically excluded from further documentation under the National

Environmental Policy Act (NEPA) in accordance with:

1) 43 CFR Part 46.210 (f) Routine and continuing government business, including such things as supervision, administration, operations, maintenance, renovations, and replacement activities having limited context and intensity (e.g., limited size and magnitude or short-term effects).

2) 516 DM 11.9 (I) (1) Emergency Stabilization – Planned actions in response to wildfires, floods, weather events, earthquakes, or landslips that threaten public health or safety, property, … and are necessary to repair or improve lands unlikely to recover to a management approved condition as a result of the event. Such activities shall be limited to repair and installation of essential erosion control structures, replacement or repair of existing culverts, roads, trails, fences, and minor facilities, and removal of hazard trees, rocks, soil, and other mobile debris from, on, or along roads, trails, campgrounds, and watercourses.

3) 516 DM 11.11 (J) (3) Restoring wetlands, streams, riparian areas or other water bodies by removing, replacing, or modifying water control structures such as, but not limited to, dams, levees, dikes, ditches, culverts, pipes, drainage tiles, valves, gates, and fencing, to allow waters to flow into natural channels and floodplains and restore natural flow regimes to the extent practicable where valid existing rights or special use authorizations are not unilaterally altered or canceled.

E. EXTRAORDINARY CIRCUMSTANCES REVIEW

The Proposed Action will not:

(a) Have significant impacts on public health or safety.

Replacing the Enchanted Pond outflow system would have a positive impact to public safety.

There would be positive safety impacts because replacing the compromised outflow system would prevent water overflow into the surrounding meadow. With the replacement, the water leaking under the outflow pipe will be corrected to improve structural stability of the pond embankment and prevent future erosion issues.

(b) Have significant impacts on such natural resources and unique geographic characteristics as historic or cultural resources; park, recreation or refuge lands;

wilderness areas; wild or scenic rivers; national natural landmarks; sole or principal drinking water aquifers; prime farmlands; wetlands; floodplains; national monuments;

migratory birds; and other ecologically significant or critical areas.

There are no significant impacts on natural resources and unique geographic characteristics such as historic or cultural resources. There are no ecologically significant or critical areas that would prevent the project from occurring. Without a functioning infrastructure at Enchanted Pond water cannot be controlled, and the pond cannot be irrigated effectively. Therefore, the overflow system replacement is extremely important for the health of the pond ecosystems.

https://www.ecfr.gov/current/title-43/subtitle-A/part-46#p-46.210(a)

(c) Have highly uncertain and potentially significant environmental effects or involve unique or unknown environmental risks.

The Proposed Action would not have uncertain or potential significant environmental effects because this type of action has already been implemented for other outflow system replacements.

For example, there was a similar project of replacing a culvert in the Meadowood SRMA along the Wood Thrush Trail. Final outcomes from other outflow systems and culvert projects provide confidence the Proposed Action would not have uncertain, unique, or unknown environmental effects.

(d) Establish a precedent for future action or represent a decision in principle about future actions with potentially significant environmental effects.

The action would not set a precedent for future actions within the Eastern States because it has already been done before. An outflow system replacement has already occurred within

Meadowood SRMA.

(e) Have a direct relationship to other actions that implicate potentially significant environmental effects.

The outflow system replacement provides favorable long-term benefits to ensure proper flow regulation to prevent future erosion issues and provide a healthier ecosystem.

(f) Have significant impacts on properties listed, or eligible for listing, on the National

Register of Historic Places as determined by the bureau.

The Proposed Action would not have significant impacts on properties listed, or eligible for listing, on the National Register of Historic Places. The BLM has fully assessed the site and determined that the Proposed Action under Section 106 of the National Historic Preservation Act

(NHPA) would result in no effects to historic properties.

(g) Have significant impacts on species listed, or proposed to be listed, on the List of

Endangered or Threatened Species, or have significant impacts on designated Critical

Habitat for these species.

BLM specialists have assessed the location of the outflow system replacement and have determined that the Proposed Action would not have significant impacts on proposed or listed species of the Endangered Species Act (ESA) nor there be negative impacts to designated

Critical Habitat for these or other species in the project area. The Northern Long-eared Bat and the Tricolored Bat have habitat ranges overlapping the project area in the Meadowood SRMA, and are listed as endangered and proposed endangered, respectively. The United States Fish and

Wildlife IPaC Determination Key (Attachment 4) result shows that the project would have No

Effect to the bat species. The Monarch Butterfly is listed as proposed threatened; however, the project would also have no effect on the species or its critical habitat in the project area.

(h) Significantly limit access to and ceremonial use of Indian sacred sites on Federal lands by Indian religious practitioners or significantly adversely affect the physical integrity of such sacred sites.

The area around Enchanted Pond would not limit access to and prevent ceremonial use of Indian sacred sites on Federal lands by Indian religious practitioners or significantly adversely affect the physical integrity of such sacred sites (EO 13007).

(i) Contribute to potentially significant effects resulting from the introduction, continued existence, or spread of noxious weeds or non-native invasive species known to occur in the area or from other actions that promote the introduction, growth, or expansion of the range of such species (Federal Noxious Weed Control Act).

The replacement of the outflow system is in an area with invasive species; however, the equipment would be washed before and after the equipment is moved in and out of the project area. This would ensure that there is no contribution to the introduction or spread of further invasive species or noxious weeds. Furthermore, the equipment used on the project would be from the same area which would mitigate the spread of invasive species. Any new material brought into the project site (e.g., dirt, rock, sand, etc.) would be locally sourced and screened before placing onto site.

F. CONCLUSION

This categorical exclusion is appropriate in this situation because there are no extraordinary circumstances that may significantly affect the environment. The Proposed Action has been reviewed, and none of the extraordinary circumstances described in 43 CFR Part 46.215 apply.

I considered the Proposed Action, NEPA compliance statement, and review of extraordinary circumstances in my determination there is no potential for significant impacts from this project.

G. SIGNATURE

Responsible Official: _______________________________ Date: ________________

Nick Weber

Field Manager - Lower Potomac Field Station

Responsible Official: _______________________________ Date: ________________

Pamela Mathis

District Manager

Contact Person

For additional information concerning this categorical exclusion review, please contact Nicholas

Weber, Lower Potomac Field Station Manager, nweber@blm.gov, (703) 339-3461.

mailto:nweber@blm.gov

ATTACHMENTS

ATTACHMENT 1

Meadowood SRMA Trail Map

ATTACHMENT 2

Current Condition of Enchanted Pond Inflow System

Pond intake is clogged

ATTACHMENT 3

Current Condition of Enchanted Pond Outflow System

Debris, silt, rocks, and other materials clogged the pipe.

This caused the pipe to have structural issues, therefore the water leaks under the pipe and not through it.

ATTACHMENT 4

U.S. Fish and Wildlife Service IPaC