US Customs and Border Protection – Environmental Assessment (TPD2108035)

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FINAL

ENVIRONMENTAL ASSESSMENT ADDRESSING THE

PROPOSED IMPROVEMENT, MAINTENANCE, AND REPAIR OF 1418 FIREBREAK ROAD IN THE CHULA VISTA STATION AREA OF RESPONSIBILITY OF THE

U.S. BORDER PATROL,

SAN DIEGO SECTOR, CALIFORNIA

DEPARTMENT OF HOMELAND SECURITY

U.S. CUSTOMS AND BORDER PROTECTION

U.S. BORDER PATROL

AUGUST 2021

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TABLE OF CONTENTS

1            INTRODUCTION…………………………………………………………………………….. 1-1

1.1         BACKGROUND………………………………………………………………………. 1-1

1.2         LOCATION……………………………………………………………………………… 1-2

1.3         PURPOSE OF AND NEED FOR THE PROPOSED ACTION……….. 1-2

1.4         PUBLIC INVOLVEMENT………………………………………………………… 1-5

1.5         FRAMEWORK FOR ANALYSIS………………………………………………. 1-6

2            PROPOSED ACTION AND ALTERNATIVES…………………………………. 2-1

2.1         INTRODUCTION…………………………………………………………………….. 2-1

2.2         SCREENING CRITERIA FOR ALTERNATIVES……………………….. 2-1

2.3         ALTERNATIVE 1: PARTIAL ROAD IMPROVEMENT……………… 2-1

2.4         ALTERNATIVE 2: COMPLETE ROAD IMPROVEMENT………….. 2-3

2.5         ALTERNATIVE 3: IMPROVE DRAINAGE FEATURES WITHOUT

WIDENING ROAD (PREFERRED ALTERNATIVE)………………….. 2-4

2.6         NO ACTION ALTERNATIVE…………………………………………………… 2-5

2.7         COMPARISON OF ALTERNATIVES……………………………………….. 2-5

3            AFFECTED ENVIRONMENT………………………………………………………….. 3-1

3.1         PRELIMINARY IMPACT SCOPING…………………………………………. 3-1

3.1.1         Socioeconomic Resources, Environmental Justice, and Protection

of Children……………………………………………………………………. 3-2

3.1.2         Roadways and Traffic…………………………………………………….. 3-2

3.1.3         Hazardous Materials and Waste Management…………………… 3-2

3.1.4         Aesthetic and Visual Resources………………………………………. 3-2

3.1.5         Health and Human Safety……………………………………………….. 3-2

3.2         LAND USE………………………………………………………………………………. 3-3

3.2.1         Definition of the Resource………………………………………………. 3-3

3.2.2         Affected Environment……………………………………………………. 3-4

3.2.3         Environmental Consequences…………………………………………. 3-7

3.3         GEOLOGY AND SOILS……………………………………………………………. 3-8

3.3.1         Definition of the Resource………………………………………………. 3-8

3.3.2         Affected Environment……………………………………………………. 3-8

3.3.3         Environmental Consequences……………………………………….. 3-10

3.4         VEGETATION……………………………………………………………………….. 3-14

3.4.1         Definition of the Resource…………………………………………….. 3-14

3.4.2         Affected Environment………………………………………………….. 3-15

3.4.3         Environmental Consequences……………………………………….. 3-18

3.5         TERRESTRIAL AND AQUATIC WILDLIFE RESOURCES……… 3-20

3.5.1         Definition of the Resource…………………………………………….. 3-20

3.5.2         Affected Environment………………………………………………….. 3-20

3.5.3         Environmental Consequences……………………………………….. 3-21

3.6         THREATENED AND ENDANGERED SPECIES………………………. 3-23

3.6.1         Definition of the Resource…………………………………………….. 3-23

3.6.2         Affected Environment………………………………………………….. 3-24

3.6.3         Environmental Consequences……………………………………….. 3-39

3.7         HYDROLOGY AND GROUNDWATER 3-43

3.7.1         Definition of the Resource……………………………………………………………………………………… 3-43

3.7.2         Affected Environment……………………………………………………………………………………… 3-43

3.7.3         Environmental Consequences……………………………………………………………………………………… 3-44

3.8         SURFACE WATERS AND WATERS OF THE UNITED STATES 3-46

3.8.1         Definition of the Resource……………………………………………………………………………………… 3-46

3.8.2         Affected Environment……………………………………………………………………………………… 3-48

3.8.3         Environmental Consequences……………………………………………………………………………………… 3-50

3.9         FLOODPLAINS 3-51

3.9.1         Definition of the Resource……………………………………………………………………………………… 3-51

3.9.2         Affected Environment……………………………………………………………………………………… 3-51

3.9.3         Environmental Consequences……………………………………………………………………………………… 3-52

3.10      AIR QUALITY 3-53

3.10.1      Definition of the Resource……………………………………………………………………………………… 3-53

3.10.2      Affected Environment……………………………………………………………………………………… 3-54

3.10.3      Environmental Consequences……………………………………………………………………………………… 3-54

3.11      NOISE 3-60

3.11.1      Definition of the Resource……………………………………………………………………………………… 3-60

3.11.2      Affected Environment……………………………………………………………………………………… 3-61

3.11.3      Environmental Consequences……………………………………………………………………………………… 3-61

3.12      CULTURAL RESOURCES 3-64

3.12.1      Definition of the Resource……………………………………………………………………………………… 3-64

3.12.2      Affected Environment……………………………………………………………………………………… 3-65

3.12.3      Environmental Consequences……………………………………………………………………………………… 3-68

3.13      RECREATION AND ACCESS 3-69

3.13.1      Definition of the Resource……………………………………………………………………………………… 3-69

3.13.2      Affected Environment……………………………………………………………………………………… 3-70

3.13.3      Environmental Consequences……………………………………………………………………………………… 3-70

4            CUMULATIVE AND OTHER IMPACTS…………………………………………………………………………………………………………… 4-1

4.1         CUMULATIVE IMPACTS 4-1

4.1.1         Past, Present, and Reasonably Foreseeable Future Actions……………………………………………………………………………………… 4-1

4.1.2         Cumulative Analysis by Resource Area……………………………………………………………………………………… 4-3

4.2         RELATIONSHIP BETWEEN THE SHORT-TERM USE OF THE ENVIRONMENT AND LONG-TERM PRODUCTIVITY 4-8

4.3         CEQA FINDINGS OF SIGNIFICANCE 4-8

4.4         GROWTH-INDUCING IMPACTS 4-8

5            REFERENCES…………………………………………………………………………………………………………… 5-1

6            LIST OF PREPARERS…………………………………………………………………………………………………………… 6-1

FIGURES & PHOTOGRAPHS

Figure 1-1. General Location Map……………………………………………………………………………………………………………………. 1-3

Figure 1-2. Project Location……………………………………………………………………………………………………………………. 1-4

Photograph 1-1. Vehicle traversing poor road conditions……………………………………………………………………………………………………………………. 1-5

Photograph 1-2. Erosion on existing roadbed……………………………………………………………………………………………………………………. 1-5

Figure 2-1. Project Alternatives……………………………………………………………………………………………………………………. 2-6

Figure 2-2. Example Water Bar Design and Construction (Keller and Sherar 2003)……………………………………………………………………………………………………………………. 2-7

Figure 2-3. Water Bar Perspective View……………………………………………………………………………………………………………………. 2-7

Photograph 2-1. Example Water Bar Location……………………………………………………………………………………………………………………. 2-8

Photograph 2-2. Example Water Cutout Location……………………………………………………………………………………………………………………. 2-8

Figure 3-1. Critical Habitat……………………………………………………………………………………………………………………. 3-26

Figure 3-2. Water Features within the Proposed Project Area……………………………………………………………………………………………………………………. 3-49

TABLES

Table 1-1. Key Permits and Approvals (as applicable) and Interagency Coordination……………………………………………………………………………………………………………………. 1-8

Table 2-1. Comparison of Features of Each Alternative……………………………………………………………………………………………………………………. 2-9

Table 2-2. Comparison of Purpose and Need with Alternatives Summary……………………………………………………………………………………………………………………. 2-10

Table 3-1. Land Ownership within the Project Area……………………………………………………………………………………………………………………. 3-5

Table 3-2. Major Faults within the Vicinity of 1418 Firebreak Road……………………………………………………………………………………………………………………. 3-10

Table 3-3. Vegetation Communities Occurring in the Project Area……………………………………………………………………………………………………………………. 3-16

Table 3-4. Approximate Surface Area to be Graded During Maintenance and Repair Activities……………………………………………………………………………………………………………………. 3-56

Table 3-5. 2020 Estimated Construction Air Emissions from Alternative 1……………………………………………………………………………………………………………………. 3-57

Table 3-6. 2020 Estimated Construction Air Emissions from Alternative 2……………………………………………………………………………………………………………………. 3-58

Table 3-7. 2020 Estimated Construction Air Emissions from Alternative 3……………………………………………………………………………………………………………………. 3-59

Table 3-8. Common Sounds and Their Levels……………………………………………………………………………………………………………………. 3-60

Table 3-9. Predicted Noise Levels for Typical Construction Equipment……………………………………………………………………………………………………………………. 3-62

Table 4-1. CEQA Findings of Significance for the Proposed Action……………………………………………………………………………………………………………………. 4-11

APPENDICES

Appendix A: Road Classifications and Maintenance and Repair Standards Appendix B: Public Involvement Materials

Appendix C: Applicable Laws, Regulations, and Executive Orders Appendix D: Best Management Practices and Mitigation Measures Appendix E Water Bar and Water Cutout Location Photographs Appendix F: Soil Maps

Appendix G: Vegetative Community Maps Appendix H: Air Quality Emissions Calculations

1    INTRODUCTION

U.S. Customs and Border Protection (CBP) proposes to improve, maintain, and repair 1418 Firebreak Road in the Chula Vista Station (CHU) Area of Responsibility (AOR) of the U.S. Border Patrol (USBP) San Diego Sector (SDC), California, to support USBP operations. The objective of this project would be to improve 1418 Firebreak Road from a Functional Classification 4 (FC-4) two-track road to a FC-2 all-weather roadway.

This Environmental Assessment (EA) was prepared to describe and assess the potential environmental and socioeconomic impacts of the Proposed Action. This EA complies with the National Environmental Policy Act (NEPA) of 1969, as amended (42 United States Code [U.S.C.] Section 4321–4347); the Council on Environmental Quality’s (CEQ) Regulations for Implementing the Procedural Provisions of the National Environmental Policy Act (40 Code of Federal Regulations [CFR] Parts 1500–1508); and Department of Homeland Security’s Instructional Manual 023-01-001-01, Rev. 01, Implementing the National Environmental Policy Act. In addition, this EA also meets the requirements of the California Environmental Quality Act (CEQA).

This EA is organized into six sections plus appendices. Section 1 provides background information on the existing 1418 Firebreak Road, identifies the purpose of and need for the Proposed Action, describes the area in which the Proposed Action would occur, and explains the public involvement process. Section 2 provides a detailed description of the Proposed Action and alternatives, including the No Action Alternative. Section 3 describes existing environmental conditions in the area where the Proposed Action would occur and identifies potential environmental impacts that could occur within each resource area. Section 4 contains an analysis of the cumulative and other impacts that the Proposed Action, combined with other projects in the area, could have on the environment. Sections 5 and 6 provide a list of references used to develop this EA, and a list of preparers who developed this EA, respectively. Finally, the appendices include other information pertinent to the development of this EA.

1.1        BACKGROUND

The mission of the USBP is to detect and prevent cross-border violators, terrorists, and terrorist weapons from entering the United States, and prevent illegal trafficking of people and contraband. In many areas, tactical infrastructure, of which roads are considered an important component, is a critical element of border security, and contributes as a force multiplier for controlling and preventing illegal border intrusion. To achieve effective control of our nation’s borders, CBP uses a multi-prong approach including a combination of personnel, technology, and infrastructure; the mobilization and rapid deployment of people and resources; and the fostering of partnerships with other law enforcement agencies. CBP must ensure that tactical infrastructure functions as intended, which includes facilitation of meeting the following mission requirements:

• Establishing substantial probability of apprehending terrorists and their weapons as they attempt to illegally enter between the Ports of Entry (POEs)

• Deterring illegal entries through improved enforcement
• Detecting, apprehending, and deterring smugglers of humans, drugs, and other contraband.

Furthermore, well-maintained tactical infrastructure allows ready access to the U.S./Mexico international border and environs for rapid response to detected threats and facilitates the ability to adjust quickly to changing threats.

1.2        LOCATION

The project is east of Lower Otay Reservoir in San Diego County, California (see Figure 1-1). The valley is situated north of Otay Mountain and east of Lower Otay Lake. 1418 Firebreak Road connects to a larger dirt road south of a gated junction with Otay Lakes Road. There are four landowners along the road’s route, including Bureau of Land Management (BLM), United States Fish and Wildlife Service (USFWS), City of Chula Vista (which is managed by the County of San Diego) and the California Department of Fish and Wildlife (CDFW). The Proposed Action’s staging area and the access road from Otay Lakes Road is on the CDFW Otay Mountain Ecological Reserve (OMER). The western portion of 1418 Firebreak Road crosses CDFW OMER and the USFWS San Diego National Wildlife Refuge (NWR). A major portion of the road is on BLM land designated as the Otay Mountain Wilderness. The southern end of the road crosses Otay Ranch Preserve (see Figure 1-2) and is managed by the City of Chula Vista and County of San Diego through a Joint Powers Agreement. The road is gated and motorized access by the public is prohibited. The majority, if not all, of motorized traffic on the road is USBP traffic.

1.3        PURPOSE OF AND NEED FOR THE PROPOSED ACTION

The purpose of the Proposed Action is to ensure that the physical integrity of the existing road and associated supporting elements continue to perform as intended to assist the USBP in securing the U.S/Mexico international border in California. The improvement of the road would enhance agent safety and effectiveness by providing efficient, reliable, and safe routes to remote areas that require patrolling. The road is critical to SDC’s ability to maintain easy access to otherwise inaccessible portions of the border region by linking Otay Lakes Road to Otay Mountain, an area with high rates of apprehension of cross border violators. The road also provides a high point for visibility for USBP agents. The current FC-4 two-track road is composed of unimproved road, wagon trail, and 4-wheel drive road and is 10-12 feet wide through most of its length (see Photograph 1-1). As “two-track” implies, the road consists of two parallel tracks created by the loss of vegetation where the tires make contact with and compact the earth, between which lies a strip of low-growth vegetation (see Appendix A). In many areas, the central vegetated strip has succumbed to erosion (see Photograph 1-2). The road has received no maintenance in over 10 years; some prior blading activity is still evident. The road has no crown and does not have any improved drainage features or ditches. Road deterioration has occurred to the extent that drivers have widened the existing route and created a section of new route to avoid the extreme erosion. The proposed activities would ensure that the road is passable, providing faster response time to border incidents in strategically valuable areas.

The need for the Proposed Action is to ensure that the increased level of border security provided by access along 1418 Firebreak Road is not compromised by natural events or breaches in road integrity. CBP must ensure that tactical infrastructure functions as it is intended.

Figure 1-1. General Location Map

Figure 1-2. Project Location

Photograph 1-1. Vehicle traversing poor             Photograph 1-2. Erosion on existing road conditions                                                              roadbed

1.4        PUBLIC INVOLVEMENT

Agency and public involvement in the NEPA process promotes open communication between the public and the government and enhances the decision-making process. All persons or organizations having a potential interest in the Proposed Action are encouraged to participate in the decision- making process by submitting comments. NEPA and CEQ guidance direct agencies to make their NEPA documents available to the public during the decision-making process and prior to actions being taken. The premise of NEPA is that the quality of federal decisions will be enhanced if additional information is provided to the public and the public is involved in the planning process.

Through the public involvement process, CBP notified by mail all relevant federal, state, and local agencies of the Proposed Action and the availability of the Draft EA. CBP requested input on environmental concerns these agencies had regarding the Proposed Action. This public involvement process provided CBP with the opportunity to consider and incorporate state and local input in decisions regarding implementation of this federal proposal.

CBP coordinated with agencies such as USFWS; BLM; U.S. Army Corps of Engineers (USACE); CDFW; the State Historic Preservation Officer (SHPO), which is a component of the California Office of Historic Preservation; San Diego Regional Water Quality Control Board (RWQCB); San Diego County Air Pollution Control District; other local agencies; Native American tribes, and the public.

Consultation with USFWS began in spring of 2019 with the Notice of Preparation for an EA. USFWS then identified potential impacts to the San Diego refuge, and federally listed species and their critical habitats. Formal consultation was requested in September 2020 for the San Diego fairy shrimp, Quino checkerspot butterfly, Least Bell’s vireo, and California gnatcatcher with the submission of the Biological Assessment. In early 2021, USFWS identified potential impacts to Riverside fairy shrimp and requested the addition of the species to the formal consultation process in February 2021. A final Biological Opinion for San Diego and Riverside fairy shrimp was dated May 26, 2021. Quino checkerspot butterfly, Least Bell’s vireo and California gnatcatcher were addressed under informal consultation. Consultation with the California SHPO was completed, and concurrence was given.

A Notice of Availability for this EA and draft Finding of No Significant Impact (FONSI) were published in the San Diego Union Tribune for the purpose of soliciting comments on the Proposed Action and alternatives, and to involve the local community in the decision-making process.

Throughout the NEPA process, the public was able to obtain information concerning the status and progress of the EA via the project website at https://www.cbp.gov/about/environmental- management-sustainability/documents/docs-review. Comments received were incorporated into the Final EA. Comment letters and other agency and public involvement materials are included in Appendix B of the Final EA.

1.5        FRAMEWORK FOR ANALYSIS

NEPA is a federal statute requiring the identification and analysis of potential environmental impacts from proposed federal actions before those actions are taken. CEQ is the principal federal agency responsible for the administration of NEPA. CEQ regulations mandate that all federal agencies use a systematic, interdisciplinary approach to environmental planning and the evaluation of actions that might affect the environment. This process identifies and evaluates potential environmental consequences associated with a proposed action and considers alternative courses of action. The intent of NEPA is to protect, restore, or enhance the environment through well- informed federal decisions.

Recent changes to the CEQ regulations implementing NEPA (40 CFR §§ 1500–1508) became effective on September 14, 2020 (85 Fed. R. 43304-76 [July 16, 2020]). As stated in 40 CFR § 1506.13, the new regulatory changes apply to any NEPA process begun after September 14, 2020. This EA substantively commenced prior to that date, as shown by the scoping letters sent to stakeholders on April 30, 2019. Therefore, this EA conforms to the CEQ NEPA implementing regulations that were in place prior to September 14, 2020.

The process for implementing NEPA is codified in 40 CFR §§ 1500–1508, Regulations for Implementing the Procedural Provisions of the National Environmental Policy Act. CEQ was established under NEPA to implement and oversee federal policy in this process. CEQ regulations specify that an EA may be prepared for the following reasons:

• Providing evidence and analysis to determine whether to prepare a FONSI or an Environmental Impact Statement (EIS).
• Aiding in an agency’s compliance with NEPA when an EIS is unnecessary.
• Facilitating preparation of an EIS when one is necessary.

Within the Department of Homeland Security (DHS) and CBP, NEPA is implemented using DHS Instruction Manual 023-01-001-01 Rev. 01, Implementing the National Environmental Policy Act, and CBP policies and procedures.

To comply with NEPA, the planning and decision-making processes for actions proposed by federal agencies require a study of other relevant environmental statutes and regulations. However, the NEPA process does not replace procedural or substantive requirements of other environmental statutes and regulations. Rather, it addresses them collectively in the form of an EA or EIS, enabling the decision maker to have a comprehensive view of major environmental issues and requirements associated with a proposed action. Per CEQ regulations, NEPA requirements must be integrated “with other planning and environmental review procedures required by law or by agency so that all such procedures run concurrently, rather than consecutively.”

Within the NEPA framework of environmental impact analysis, additional authorities that could be applicable include the Clean Air Act (CAA), Clean Water Act (CWA) (including a National Pollutant Discharge Elimination System [NPDES] stormwater discharge permit and Section 404 permit), Endangered Species Act (ESA), Migratory Bird Treaty Act (MBTA), National Historic Preservation Act (NHPA), Archaeological Resources Protection Act, and various Executive Orders. A summary of laws, regulations, and Executive Orders that could be applicable to the Proposed Action is presented in Appendix C.

CEQA (California Public Resources Code Sections 21000–21177) is a statute that requires the State of California and local agencies to identify significant environmental impacts of their actions and to avoid or mitigate those impacts, if feasible. CEQA applies to any discretionary action by a state or local agency. CEQA applies to projects that have the potential to result in a physical change to the environment or that might be subject to several discretionary approvals by governmental agencies, including construction activities, clearing of or grading land, improvements to existing structures, and activities or equipment involving the issuance of a permit.

For this project, CEQA is relevant because CBP would likely be required to obtain Section 401 certification from the San Diego Regional Water Quality Control Board for potential discharge to state or tribal waters, including wetlands. To paraphrase Section 15221 of the Guidelines for Implementation of the CEQA (California Code of Regulations, Title 14, Division 6, Chapter 3, Sections 15000–15387), an EIS or EA and FONSI prepared under NEPA can be used instead of an Environmental Impact Report or Negative Declaration prepared under CEQA, provided the NEPA documentation meets CEQA requirements.

Table 1-1 lists major federal and state permits, approvals, and interagency coordination that could be required regarding the proposed improvement, maintenance, and repair of 1418 Firebreak Road.

Table 1-1. Key Permits and Approvals (as applicable) and Interagency Coordination

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2    PROPOSED ACTION AND ALTERNATIVES

2.1        INTRODUCTION

This section provides detailed information on CBP’s proposal to improve, maintain, and repair 1418 Firebreak Road in the CHU AOR of the USBP SDC to support USBP operations. As discussed in Section 1.5, the NEPA process evaluates potential environmental consequences associated with a proposed action and considers alternative courses of action. Alternatives must satisfy the purpose of and need for a proposed action, which are defined for this action in Section 1.3. CEQ guidance advocates the inclusion of a No Action Alternative against which potential effects can be compared. No action in such cases would mean the proposed activity would not take place, and the resulting environmental effects from taking no action would be compared with the effects of permitting the proposed activity or an alternative activity to go forward. While the No Action Alternative would not satisfy the purpose of or need for the Proposed Action, it is analyzed in detail as recommended by CEQ regulations.

2.2        SCREENING CRITERIA FOR ALTERNATIVES

Each alternative to the Proposed Action considered in the EA must meet CBP’s purpose of and need for the Proposed Action (as described in Section 1.3). The following screening criteria were used to develop the Proposed Action and evaluate potential alternatives:

• Maintaining Situational Awareness. Proposed activities must provide USBP agents the ability to stay abreast of cross-border violations in the area of 1418 Firebreak Road.

• Facilitating Effective Response. Proposed activities must facilitate the efficient and effective response to cross border violations in the area of 1418 Firebreak Road.

• Minimize and/or Avoid Environmental Impacts. Proposed activities must consider the environment to minimize and avoid current and future impacts.

2.3        ALTERNATIVE 1: PARTIAL ROAD IMPROVEMENT

Under Alternative 1, 1418 Firebreak Road would be improved to a FC-2 level, all-weather roadway for 4,885 feet (ft) from Otay Lakes Road to a point where the road enters the Otay Mountain Wilderness on BLM property (see Figure 2-1). FC-2 roads typically consist of two 3.6-meter (12 ft) travel lanes at a 4 percent cross-slope. A cross-slope is built into the road to provide a drainage gradient so that water will run off the surface to a drainage system such as a street gutter or ditch. Under this alternative, 1418 Firebreak Road would be widened where necessary to ensure a minimum 24-ft width from Otay Lakes Road to the boundary of the Otay Mountain Wilderness. Parallel ditches with a 1-vertical to 3-horizontal (1V:3H) front slope and 1-vertical to 4-horizontal (1V:4H) backslope would be cut on the downslope side of the road to allow for proper drainage. Imported roadway material would be added to the road to achieve a minimum 150-millimeter (6-inch) deep, well-graded roadbed shaped with a defined crown section (see Figure 2-2). It is anticipated that construction would be completed within six to

twelve weeks and would comply with all seasonal restrictions. All necessary materials such as gravel, topsoil, or fill would be imported to the site. No on-site materials will be used except for the material within the existing roadway. To the maximum extent practicable, all material sources would be certified weed-free.

Wherever possible, CBP would limit disturbance to the proposed width of the proposed FC-2 road and ancillary structures. Where turnouts and passing lanes would be required for construction, CBP would use currently disturbed areas (e.g., locations where a secondary trail has been created due to impassable road conditions), to the maximum extent practicable, and restore all such areas upon completion of the Proposed Action. More information regarding temporary and permanent impacts can be found in Appendix D for all alternatives discussed.

Equipment and materials would be stored at a staging area at the entrance to the project area. The staging area would be an unimproved, previously disturbed area (see Figure 2-1). The types and numbers of equipment used would be kept to a minimum. It is anticipated that backhoes, graders, and dump trucks would be necessary for road improvement activities. Water trucks would be employed to aid in dust suppression. All equipment would be cleaned prior to entering and departing the project corridor to minimize the spread and establishment of non-native invasive plant species. See Appendix D for additional best management practices (BMP).

Seven water bars would be installed in locations where washouts occur to allow the agents to drive on the designated road rather than seek an alternate route during flood events (see Figure

2-1 and Appendix E). There are several areas along 1418 Firebreak Road with extensive damage due to agents driving outside of the road footprint to avoid severely washed out sections of the road (see Photograph 1-2). Water bars are frequently spaced, constructed drainage devices that use road material mounded in the road surface to interrupt the flow of water and divert it off the road surface (see Figure 2-2 and Photograph 2-1). The frequency of water bar placement is determined by the road gradient within the impacted area. In road areas with an approximate 5 percent slope, the interval would typically be 125 ft. Should slopes of 5 – 10 percent be encountered, the interval would be reduced to 100 ft. Under the Proposed Action, the water bars would be designed to be drivable by high clearance vehicles (see Figure 2-2).

Eight water cutouts would be installed with the implementation of Alternative 1 (see Figure 2-1 and Appendix E). These are earthen low water crossings already present in the road. The outfall for the water cutout would have a 3-foot by 3-foot rip-rap outfall protection apron.

The finished road would be a reinforced roadbed with a soil stabilizer (e.g., Lignin, Soiltac®, Envirotec, or some other suitable soil stabilizer) applied during the late summer/early fall months. Proper use of a non-toxic road stabilizer helps to avoid impacts on federally listed species habitat by minimizing road run-off and is neither toxic nor harmful to sensitive species.

Road maintenance and repair would include reactive maintenance and repair activities (e.g., resolving damage from use or severe weather events) and preventive/scheduled maintenance and repair activities designed to ensure ongoing operability and environmental sustainability (e.g., soil erosion preventive measures). All maintenance and repair would occur via a periodic work plan based on anticipated situations within each sector and funding availability. Prior to any maintenance/non-emergency repairs, coordination with landowners would occur. Furthermore,

such work would be done outside of any breeding/flight season for listed species present. Maintenance and repair requirements could change over time based on changes in usage or priority but would likely occur at least annually and would not exceed the scope of the Proposed Action.

Maintenance and repair would consist of grading and resurfacing existing areas of the roads that have been eroded by surface water flows, filling potholes, and removing protruding boulders. Trees and other vegetation within, or overhanging, the existing roadway would be trimmed, grubbed, or cut back to facilitate safe vehicle passage. Any vegetation that has established within the existing road would be removed, cleared, or trampled.

Some activities may need to be conducted in areas immediately adjacent to the existing road footprint (road edges). For example, equipment might need to be operated off existing roads to remove debris from ditches, and to access and maintain roads. Temporary impacts on vegetation and soil resulting from these activities would be minimized through appropriate heavy equipment operation techniques, such as installing temporary construction mats, reducing operating speeds, using the initial ingress and egress points, and selecting appropriately sized equipment for the area and project.

For water-control features (such as ditches), activities would include cleaning, maintaining, repairing, or replacing features, as needed. Implementing improved water drainage measures includes ensuring road crowns shed water and runoff flows to established drainage ditches or other water-control features as needed to control runoff and prevent deterioration of existing infrastructure or surrounding land. The stabilization of roads with the use of a soil binder would function as a means to reduce erosion and improve road strength. The application of a soil binder would be completed on an annual basis or less frequently, depending on need.

Heavy equipment would be needed for activities such as grading, filling, and compacting. Equipment staging would occur on the existing road footprint or at existing CBP laydown yards. All equipment would be hauled into sites as needed. Required equipment would likely include dump trucks, road graders, backhoes, bulldozers, drum roller/compactors, and water trucks.

2.4        ALTERNATIVE 2: COMPLETE ROAD IMPROVEMENT

Under this alternative, 1418 Firebreak Road would be improved to a FC-2 level, all-weather roadway for the entire 12,983 ft from Otay Lakes Road to a point where the road terminates on the City of Chula Vista property that is surrounded by the Otay Mountain Wilderness area (see Figure 2-1).

Nine water bars would be installed where washouts occur to allow the agents to drive on the designated road rather than seek alternate routes during flood events. All construction methods would be as described in Alternative 1 with the addition of rip-rap. Rip-rap crossings are only on BLM property and therefore only required for Alternative 2 because it is the only alternative that includes a stream. These would be in-road stretches of 6-inch rip-rap placed the width of the driving surface and approximately 60 feet in length.

Nineteen water cutouts would be installed with the implementation of Alternative 2 (see Figure 2-1 and Appendix E). As with Alternative 1, the outfall for the water cutout would have a 3-foot by 3-foot rip-rap outfall protection apron.

It is the current policy of BLM to prohibit road maintenance or improvements within the Otay Mountain Wilderness boundary. The Wilderness Act (16 U.S.C. 1131 et seq.) and the Otay Mountain Wilderness Act of 1999 do provide for exceptions that could grant BLM permission for authorizing these activities. The Otay Mountain Wilderness Act recognizes that, because of the proximity of the Wilderness Area to the U.S./Mexico international border, drug interdiction and border operations need to continue, provided such management actions are conducted in accordance with the Wilderness Act. In turn, Section 5 of the Wilderness Act states that:

…in any case where State-owned or privately-owned land is completely surrounded by national forest lands within areas designated by this Act as wilderness, such State or private owner shall be given such rights as may be necessary to assure adequate access to such State-owned or privately-owned land by such State or private owner and their successors in interest. (16 U.S.C. 1131 et seq.)

These provisions could provide a mechanism for potential improvement, maintenance, and repair activities to the southern portion of 1418 Firebreak Road. CBP has determined that it would be preferable to conduct the analysis for the entire 1418 Firebreak Road should a compelling need arise, in concurrence with BLM, for improvement, maintenance, and repair activities to occur.

2.5        ALTERNATIVE 3: IMPROVE DRAINAGE FEATURES WITHOUT WIDENING ROAD (PREFERRED ALTERNATIVE)

Alternative 3 is the preferred alternative. Under this alternative, 1418 Firebreak Road would be improved to a FC-2 level, all-weather roadway for 4,885 ft from Otay Lakes Road to the point where the road enters the Otay Mountain Wilderness on BLM property. However, under this alternative, 1418 Firebreak Road would not be widened as it would be under Alternative 1. All drainage and other improvements that would be implemented under Alternative 1 would also be implemented under Alternative 3 with the exception of parallel ditches, which would not be installed under this alternative. One turnout would be added. This alternative would minimize ground disturbance and would not change the existing footprint.

Seven water bars would be installed in locations where washouts occur to allow the agents to drive on the designated road rather than seek an alternate route during flood events. All construction methods would be as described in Alternative 1.

Under this alternative, maintenance and repair of the road would include reactive maintenance and repair activities and preventive/scheduled maintenance and repair activities designed to ensure ongoing operability and environmental stewardship. All maintenance and repair activities would be as described in Alternative 1 but would be confined to the current road footprint. As with Alternative 1, locations where a secondary trail has been created due to impassable road conditions would be restored upon completion of the project. The addition of material to the road would be kept to the minimum amount needed to achieve the proposed objective.

2.6        NO ACTION ALTERNATIVE

The other alternative that will be carried forward for analysis is the No Action Alternative, as recommended by CEQ regulations. Under the No Action Alternative, CBP would not be maintaining, repairing, and improving the road.

2.7        COMPARISON OF ALTERNATIVES

The following tables provide a summary comparison of each alternative. Table 2-1 compares the features of each alternative. Table 2-2 compares how the alternatives respond to the purpose of and need for the Proposed Action. A detailed comparison of the impacts that could occur as a result of implementing each alternative is provided in Section 3.0.

Figure 2-1. Project Alternatives

Figure 2-2. Example Water Bar Design and Construction (Keller and Sherar 2003)

Figure 2-3. Water Bar Perspective View

Photograph 2-1. Example Water Bar Location

Photograph 2-2. Example Water Cutout Location

Table 2-1. Comparison of Features of Each Alternative

Key: N/A = Not Applicable

FC-2 design standards include a 24-foot road width.

Table 2-2. Comparison of Purpose and Need with Alternatives Summary

Key: FC-2 = roads typically consisting of two 3.6-meter (12-foot) travel lanes at a 4 percent cross-slope. Parallel ditches with a 1- vertical to 3-horizontal (1V:3H) front slope and 1-vertical to 4-horizontal (1V:4H) backslope allow for proper drainage. To achieve this standard, sufficient roadway material would be imported to achieve a minimum 150-millimeter (6-inch) deep, well- graded roadbed shaped with a defined crown section.

3    AFFECTED ENVIRONMENT

This section provides a discussion of the affected environment, as well as an analysis of the potential direct and indirect impacts that the alternatives could have on the affected environment. Cumulative and other impacts are discussed in Section 4. All potentially relevant resource areas were initially considered in this EA. In accordance with NEPA, CEQ regulations, and DHS Instruction Manual 023-01-001-01, Rev. 01, this evaluation focuses on those resources and conditions potentially subject to effects, and on potentially significant environmental issues deserving of study. It does not go into detail on insignificant issues.

The following categories describe various types of impacts that could potentially result from the proposed project:

• Short-term or long-term. These characteristics are determined on a case-by-case basis and do not refer to any rigid time period. In general, short-term effects are those that would occur only with respect to a particular activity or for a finite period or only during the time required for maintenance and repair activities. Long-term effects are those that are more likely to be persistent and chronic.

• Direct or indirect. A direct effect is caused by and occurs contemporaneously at or near the location of the action. An indirect effect is caused by a proposed action and might occur later in time or be farther removed in distance, but still be a reasonably foreseeable outcome of the action. For example, a direct effect of erosion on a stream might include sediment-laden waters in the vicinity of the action, whereas an indirect impact of the same erosion might lead to lack of spawning and result in lowered reproduction rates of indigenous fish downstream.

• Negligible, minor, moderate, or major. These relative terms are used to characterize the magnitude or intensity of an impact. Negligible effects are generally those that might be perceptible but are at the lower level of detection. A minor effect is slight, but detectable. A moderate effect is readily apparent. A major effect is one that is severely adverse or exceptionally beneficial.

• Adverse or beneficial. An adverse effect is one having unfavorable, or undesirable, outcomes on the man-made or natural environment. A beneficial effect is one having positive outcomes on the man-made or natural environment. A single act might result in adverse effects on one environmental resource and beneficial effects on another resource.

3.1        PRELIMINARY IMPACT SCOPING

Some environmental resources and issues that are often analyzed in an EA have been omitted from detailed analysis. The following provides the basis for such exclusions.

3.1.1           Socioeconomic Resources, Environmental Justice, and Protection of Children

Minority or low-income populations are present and could be affected by a project if the percentage of persons characterized as being a minority or low-income within the region of influence is either greater than 50 percent or meaningfully higher than in the general population or other appropriate unit of geographic analysis (e.g., community of comparison). The community of comparison should be the smallest jurisdiction for which U.S. Census data are collected that encompasses the footprint of impacts for all resource areas. CEQ also states, “A minority population also exists if there is more than one minority group present and the minority percentage, as calculated by aggregating all minority persons, meets one of the above-stated thresholds” (CEQ 1997).

Project activities would not have a significant effect on socioeconomic resources, environmental justice, or the protection of children, since there are no populations living within or nearby the survey area. Therefore, no effect on these resources would be anticipated, and therefore no detailed discussion is provided.

3.1.2           Roadways and Traffic

Project activities could cause short-term roadway closures and detours while work is underway; however, most of the roadways proposed for maintenance and repair are used solely by USBP. Therefore, the public would not be impacted by these roadway closures or detours. Roadway closures and detours would be temporary, so USBP patrols would experience only minor disruptions. As a result, impacts on roadways and transportation would be negligible and are not discussed further.

3.1.3           Hazardous Materials and Waste Management

Project activities could cause long-term adverse impacts on the environment as roadway construction vehicles containing hazardous substances and petroleum products would be deployed, which could result in a spill or release. Roadway construction would also generate solid wastes during grading and construction activities. Potential impacts from uncollected solid wastes include increased risk of injury, obstruction of draining areas, land and water pollution, and/or loss of biodiversity. However, these incidents are unlikely to occur and therefore impacts on the environment would be negligible and are not discussed further.

3.1.4           Aesthetic and Visual Resources

Project activities would not have a significant impact on aesthetic and visual resources as maintenance and repair activities would occur in remote areas on or directly adjacent to the existing footprint of the roadway and no additional infrastructure would be installed.. Therefore, no effect on aesthetic and visual resources would be anticipated, and therefore no detailed discussion is provided.

3.1.5           Health and Human Safety

Project activities could cause long-term beneficial impacts to health and human safety as the improved roadway would offer a more stable and safe driving surface for vehicles. Short-term, negligible, adverse impacts on health and human safety could occur during construction; however, construction site safety is largely a matter of adherence to regulatory requirements imposed for the benefit of employees and implementation of operational practices that reduce risks of illness, injury, death, and property damage. Occupational Safety and Health Administration and the USEPA issue standards that specify the amount and type of training required for industrial workers, the use of protective equipment and clothing, engineering controls, and maximum exposure limits with respect to workplace stressors.

Contractors would be required to establish and maintain safety programs at the construction site. The proposed project would not expose members of the general public to increased safety risks. Therefore, because the Proposed Action would not introduce new or unusual safety risks, and assuming appropriate protocols are followed and implemented, detailed examination of safety is not included in this EA.

Additionally, due to the remote location of the region of analysis, the likelihood of this project impacting the health and safety of humans other than USBP agents and contractors or USBP personnel performing the road repairs is extremely low. However, minor, beneficial impacts on safety could occur from public use of repaired roads.

3.2        LAND USE

3.2.1           Definition of the Resource

The term “land use” refers to real property classifications that indicate either natural conditions or the types of human activity occurring on a parcel of land. In many cases, land use descriptions are codified in local zoning laws. However, there is no nationally recognized convention or uniform terminology for describing land use categories. As a result, the meaning of various land use descriptions, “labels,” and definitions vary among jurisdictions.

Natural property conditions can be described or categorized as unimproved, undeveloped, conservation or preservation area, and natural or scenic area. There is a wide variety of land use categories resulting from human activity. Descriptive terms often used include residential, commercial, industrial, agricultural, institutional, and recreational.

Two main objectives of land use planning are to ensure orderly growth and compatible uses among adjacent property parcels or areas. Compatibility among land uses fosters the societal interest of obtaining the highest and best uses of real property. Tools supporting land use planning include written master plans/management plans and zoning regulations. In appropriate cases, the location and extent of a proposed action needs to be evaluated for its potential effects on the proposed project corridor and adjacent land uses. The foremost factor affecting a proposed action in terms of land use is its compliance with any applicable land use or zoning regulations. Other relevant factors include matters such as existing land use in the proposed project corridor, the types of land uses on adjacent properties and their proximity to a proposed action, the duration of a proposed activity, and its permanence.

3.2.2           Affected Environment

The project area is east of Lower Otay Reservoir in San Diego County, California, located within the Otay Subregional Plan Area. The nearest town is Otay Ranch, approximately 4 miles to the west. In general, land uses and ownership in and adjacent to the project area include public land; federal, state, and local land; and vacant and undeveloped land. Public land includes cemeteries, religious facilities, libraries, post offices, fire or police stations, hospitals, military facilities, and educational institutions. Public land also includes land belonging to the Federal Government in the public domain. Federal, state, and local land ownership include wildlife refuges, ecological reserves, conservation areas, and designated wildernesses lands owned by the Federal Government. Vacant and undeveloped land is historically and currently vacant, and undeveloped land is land not placed in another land use category.

Land ownership within the project area is shown in Table 3-1. Figure 2-1 illustrates the project alternatives and various landowners.

Land Ownership. The Otay subregional resource conservation areas have been recognized as having statewide significance, to include Lower Otay Reservoir, rare and endangered plants on the lower mesa areas, and Otay Mountain.

The project area occurs on portions of the OMER, which is managed by the California Fish and Game Commission. The OMER is a public reserve of about 1,200 acres that hosts many sensitive species and habitats. This parcel is currently closed to all public access; however, permitted uses on other portions of the OMER include hiking, wildlife viewing, bike riding, and horseback riding.

Land in the San Diego NWR also composes parts of the project area. This NWR is managed by USFWS and is part of a USFWS contribution to the Multiple Species Conservation Program (MSCP), a landscape-wide habitat conservation plan to preserve habitat and species while allowing for appropriate development. Permitted uses of the land include hiking, wildlife viewing, bike riding, and horseback riding.

Alternative 2 is on portions of BLM land composing the Otay Mountain Wilderness. Otay Mountain is predominantly under BLM ownership. BLM is responsible for managing public lands and resources for multiple uses. BLM land within and around the project area is used for recreational purposes, such as hunting, hiking, horseback riding, camping, wildlife viewing, and other wilderness activities.

Alternative 2 is also on a portion of the Otay Ranch Preserve co-owned by both the City of Chula Vista and the County of San Diego. This preserve was authorized in 1996 through an agreement between the County of San Diego and the City of Chula Vista. The Preserve includes more than 11,000 acres set aside as mitigation for impacts on sensitive resources resulting from development occurring both in the county and the city.

Table 3-1. Land Ownership within the Project Area

Source: USGS 2019a

Regulatory Setting. Several federal, state, and local land use plans, policies, and regulations could be relevant to the project area for the Proposed Action. These land use plans, policies, and regulations are identified in the following paragraphs.

National Wildlife Refuge System Administration Act of 1966; National Wildlife Refuge System Improvement Act of 1997. The Act was passed to ensure that the Refuge System is managed as a national system of related lands, waters, and interests for the protection and conservation of our Nation’s wildlife resources. The National Wildlife Refuge System is the only system of federal lands devoted specifically to wildlife. It is a network of diverse and strategically located habitats with at least one refuge in each state. The passage of this Act gave guidance to the Secretary of the Interior for the overall management of the Refuge System.

South Coast Resource Management Plan. In 1994, this plan was developed to guide the future management of approximately 296,000 acres of BLM-administered public land, including 129,000 acres of BLM-administered surface land (referred to as BLM public land) and 167,000 acres of federal mineral ownership where the surface is privately owned (referred to as BLM split estate land). The 129,000 acres of BLM public land are scattered over a five-county area in 296 separate parcels. Ninety-five percent of the BLM land base in the planning area is in western San Diego and western Riverside counties, with the remainder in southwestern San Bernardino, Los Angeles and Orange counties.

Otay Mountain Wilderness Act of 1999. In 1999, the Otay Mountain Wilderness became part of the approximately 109-million-acre National Wilderness Preservation System. Consequently, it is BLM policy to prohibit road maintenance or improvement within the Otay Mountain Wilderness boundary; however, the Wilderness Act (16 U.S.C. 1131 et seq.) and the Otay Mountain Wilderness Act of 1999 do provide for exceptions that could grant BLM permission for authorizing proposed activities for Alternative 2. These exceptions could provide a mechanism for potential improvement, maintenance, and repair activities to the southern portion of 1418 Firebreak Road.

San Diego County General Plan/Otay Subregional Plan. The San Diego County General Plan is a framework for the future growth and development of the unincorporated areas of the county, particularly in the western communities. It is based on a set of 10 guiding principles designed to protect the county’s unique and diverse natural resources and maintain the character of its rural and semi-rural communities. It reflects an environmentally sustainable approach to planning that balances the need for adequate infrastructure, housing, and economic vitality, while maintaining and preserving unique communities, agricultural areas, and open space. The General Plan provides a consistent framework for land use and development decisions consistent with an established community vision. An unincorporated community’s vision, characteristics, and issues are addressed in more specific Community Plans, such as the Otay Subregional Plan. The San Diego County General Plan identifies goals and policies relevant to land use within 10 chapters, including Land Use, Housing, Circulation (Mobility), Conservation and Open Space, Safety, and Noise.

San Diego County Zoning Ordinance. The San Diego County Zoning Ordinance regulates land uses within the unincorporated areas of the county by dividing the land into zones based on the present and potential uses of the land. A “zone” is the combination of human and animal use, development type, and special planning area regulations. The San Diego County Zoning Ordinance does not apply to federally owned public lands within the county, which are defined as parcels that are identified as federally owned public lands by the San Diego County Assessor. It should be noted that most of the project area falls within these federally owned public lands.

San Diego County Board of Supervisors Policies. The following San Diego County Board of Supervisors policies could be relevant to construction and operation of facilities under Alternative 1:

• Policy I-18. Right-of-way dedication and public improvement requirements in connection with major and minor use permits.

• Policy I-49. Distribution of notification of land use hearings.
• Policy I-81. Easements and right-of ways on county-owned or special district-owned real property.

• Policy I-100. Minor encroachments into an open space easement.
• Policy I-122. Use of the county’s five percent allowable loss of coastal sage scrub by other jurisdictions.

• Policy I-138. Mitigation on county-owned land managed by the department of parks and recreation.

Multiple Species Conservation Program (MSCP). The MSCP is a comprehensive habitat conservation planning program that addresses multiple species habitat needs and the preservation of native vegetation communities in San Diego County. The MSCP is a subregional plan under the Natural Communities Conservation Program that is implemented through local subarea plans, which describe specific implementing mechanisms for the MSCP.

CBP is not a signatory to the MSCP and, therefore, is not required to comply with MSCP-specific mitigation requirements and ratios. However, wherever possible, CBP would comply with such requirements and ratios. Any CBP mitigation requirements are fulfilled through ESA Section 7 consultation with USFWS. Therefore, USBP is permitted to perform activities within any preserve, subject to applicable requirements of federal and state law with no additional permit requirements associated with the MSCP. Additionally, projects within Tier IV habitats, which include disturbed and agricultural lands, would not be required to mitigate for impacts on habitat pursuant to the South County Subarea Plan (County of San Diego 1997). See Sections 3.3.2 and 3.4.2 for more information on the MSCP.

3.2.3           Environmental Consequences

3.2.3.1            Alternative 1: Partial Road Improvement

Following the implementation of this alternative, the land use would remain the same. Alternative 1 is only on OMER and the San Diego NWR land and stops before entering the Otay Mountain Wilderness on BLM property. CBP would comply with all MSCP-specific mitigation requirements and ratios, including restrictions on motorized vehicles and permanent roads. Alternative 1 would be compatible with the existing land use categories and would not impact land use.

3.2.3.2            Alternative 2: Complete Road Improvement

Following the implementation of Alternative 2, land use would remain the same. Alternative 2 is on land composed of the OMER, San Diego NWR, Otay Mountain Wilderness, and Otay Ranch Preserve. Short-term, minor impacts would occur from construction and use of staging areas during construction. Long-term, negligible to minor, adverse impacts would be anticipated due to converting vegetated land to expand the roadway. A greater area of vegetation would be converted into parts of the improved 1418 Firebreak Road than in Alternative 1. A greater area of land than Alternative 1 would be converted into turnouts and passing lanes along the roadway. Improvements on BLM land would be prohibited under the Otay Mountain Wilderness Act of 1999 and South Coast Resource Management Plan; however, exceptions granted to CBP could allow for road improvements. Construction activities within the Otay Ranch Preserve would comply with the Otay Subregional Plan and the San Diego County Zoning Ordinance and would adhere to all relevant San Diego County Board of Supervisors policies. All construction activities would also comply with the National Wildlife Refuge System Administration Act of 1966 and the National Wildlife Refuge System Improvement Act of 1997. CBP would comply with all MSCP-specific mitigation requirements and ratios, including restrictions on motorized vehicles and permanent roads. Alternative 2 would be compatible with existing land use categories and would not significantly impact land use.

3.2.3.3            Alternative 3: Preferred Alternative (Improve Drainage Features Without Widening Road)

No new construction or change in land use would occur under Alternative 3; all activity would be confined to repair and maintenance of the current road footprint. CBP would comply with all MSCP-specific mitigation requirements and ratios. No effects on land use would be expected as a result of Alternative 3.

3.2.3.4            No Action Alternative

Under the No Action Alternative, CBP would not be maintaining, repairing, or improving the road. CBP enforcement actions would be maintained at current levels or diminish over time due to inaccessibility of the area to CBP agents. CBP would comply with all MSCP-specific mitigation requirements and ratios. The No Action Alternative would result in continuation of existing land uses. No effects on land use would be expected as a result of the No Action Alternative.

3.3        GEOLOGY AND SOILS

3.3.1           Definition of the Resource

Geological resources consist of the Earth’s surface and subsurface materials. Within a given physiographic province, these resources typically are described in terms of topography and physiography, geology, soils, and, where applicable, geologic hazards and paleontology. Topography and physiography pertain to the general shape and arrangement of a land surface, including its height and the position of its natural and human-made features. Geology is the study of the Earth’s composition and provides information on the structure and configuration of surface and subsurface features. Such information derives from field analysis based on observations of the surface and borings to identify subsurface composition.

Soils are the unconsolidated materials overlying bedrock or other parent material. Soils typically are described in terms of their complex type, slope, and physical characteristics. Differences among soil types in terms of their structure, elasticity, strength, shrink-swell potential, and erosion potential affect their abilities to support certain applications or uses. In appropriate cases, soil properties must be examined for their compatibility with certain construction activities or types of land use.

Prime farmland is protected under the Farmland Protection Policy Act (FPPA) of 1981. Prime farmland is defined as land that has the best combination of physical and chemical characteristics for producing food, feed, forage, fiber, and oilseed crops, and that is also available for these uses. The intent of the FPPA is to minimize the extent that federal programs contribute to the unnecessary conversion of farmland to non-agricultural uses. The Natural Resources Conservation Service (NRCS) is responsible for overseeing compliance with the FPPA and has developed the rules and regulations for implementation of the Act (see 7 CFR Part 658, 5 July 1984).

3.3.2           Affected Environment

Regional Geology. The project is within the Lower Californian sub-province of the Pacific Geologic Province. The sub-province includes the Peninsular Ranges and the coastal area of San

Diego. The Peninsular Ranges extend into the Los Angeles Ranges to the north and form the Baja Peninsula to the south. The Peninsular Ranges are composed of batholithic rock formed under extreme heat and pressure by solidification of magma deep within the earth’s crust. Uplift and tilting of the Peninsular Range resulted in the Elsinore and San Jacinto Faults, which form the eastern boundary of the Pacific Geologic Province. The western portion of the Lower Californian sub-province is composed of dissected, mesa-like terraces that graduate inland into rolling hills. The terrain here is underlain by sedimentary rocks composed mainly of sandstone, shale, and conglomerate beds, reflecting the erosion of the Peninsular Ranges.

The Otay Mountain area is part of the San Ysidro Mountains, which lies just north of the U.S.- Mexico border in San Diego County. Otay Mountain is part of a zone of Late Jurassic (176–200 million years old) rocks, termed the Santiago Peak Volcanics. These rocks consist of a complex blend of volcanic and sedimentary rocks formed within a submarine island-arc environment. Elevation ranges from 400 ft along the western portion to about 3,550 ft on Otay Mountain. The area rises above a mesa on the west and is deeply dissected by numerous ephemeral streams. The streams have cut steep, narrow canyons or ravines into the hillsides that dominate the area, making it extremely rugged terrain.

Topography. Elevations in the project area range from approximately 500 ft at the northern portion of the road to approximately 1,500 ft at the southern portion of the road.

Soils. Five soil associations occur within the limits of the project area (Soil Survey Staff 2019b; Bowman 1973). The southern portions of the road are predominantly characterized by San Miguel Exchequer soils, and the northern portions of the road are predominantly Olivenheim cobbly loam soils. The remaining soils are small areas of Friant rocky fine sandy loams and Redding cobbly loams on the northern portion of the project area. Of the five soil associations mapped, the Olivenhain cobbly loams, with 9 to 30 percent slopes, have a moderate potential for erosion, while the remaining soils have a severe potential for erosion. Limitations to construction also range from moderate to severe. There is no perennial water source within the survey area. Figures in Appendix F contain more detailed picture of soils in the project area.

Prime Farmland. Of the five soil associations mapped within the project area, none are considered prime farmland. Because no prime farmland soils exist within the project area, further analysis of the environmental consequences of Alternatives 1, 2, and 3 on prime farmland are not needed.

Geologic Hazards. Geologic hazards are prevalent throughout Southern California in the form of seismic events, landslides, debris flows, and rock falls. There are thousands of recognized faults in California, of which a very small number pose significant hazards. While tectonic plate motion is constant, pressure can build along the fault lines and can be released as earthquakes. The maximum size of an earthquake is related to the length of the fault. No faults are in the project area; however, the Rose Canyon fault zone and Elsinore fault zone are to the west and east of the project area, respectively. These faults have a relatively low average slip rate (rate of movement) of 2 to 5 millimeters per year. Faults with lower slip rates have correspondingly longer times between earthquakes. Major fault systems within the vicinity of the project area are outlined in Table 3-2.

Seismic movement has been assessed by the U.S. Geological Survey (USGS) and California Geological Survey (CGS), which has produced seismic hazard maps based on current information about the rate at which earthquakes occur in different areas and on how far strong shaking extends from the quake source. The Earthquake Shaking Potential maps show the levels of horizontal shaking that have a 2 in 100 chance of being exceeded in a 50-year period. The project area is within the earthquake hazard zone associated with the lowest intensity, indicating it is relatively distant from known, active faults and would experience lower levels of shaking less frequently. In this hazard zone, most earthquakes would only cause damage to weaker, masonry buildings; however, very infrequent earthquakes could still cause strong shaking. Historically, there have been up to 6-7 magnitude earthquakes in the vicinity of the project area.

Per the CGS, the project area has not been evaluated for liquefaction or landslides. The project area ranges from a deep-seated Landslide Susceptibility of Class V to Class IX. Weak rocks and steep slopes are most likely to generate landslides.

Table 3-2. Major Faults within the Vicinity of 1418 Firebreak Road

*Geologic evidence demonstrates the existence of a Quaternary Period fault of tectonic origin, whether the fault is exposed for mapping or inferred from liquefaction or other deformational features.

Source: USGS 2019b.

3.3.3           Environmental Consequences

Protection of unique geological features, minimization of soil erosion, and siting of facilities in relation to potential geologic hazards are considered when evaluating potential effects of a proposed action on geological resources. Generally, adverse effects can be avoided or minimized if proper techniques, erosion-control measures, and structural engineering design are incorporated into project development.

Effects on geology and soils would be major and adverse if they would alter the lithology (i.e., the character of a rock formation), stratigraphy (i.e., the layering of sedimentary rocks), and geological structures that control groundwater quality, distribution of aquifers and confining beds, and groundwater availability; or change the soil composition, structure, or function within the environment.

3.3.3.1            Alternative 1: Partial Road Improvement

Regional Geology. Alternative 1 would not expose people or structures to substantial adverse effects, nor would it entirely remove a geologic resource. Alternative 1 would not alter rock

formations or layering of sedimentary rock. Negligible impacts on geology would be anticipated from the implementation of Alternative 1.

Topography. Long-term, negligible, adverse impacts on topography would be anticipated from grading activities that would locally alter existing topography. The majority of areas proposed for grading have been previously graded, and, therefore, impacts would be negligible.

Soils. Under Alternative 1, road improvements to 4,885 ft of road would stop further deterioration of road conditions and prevent future erosion of the road surface from occurring. The application of soil stabilizing agents and the construction of water bars would result in safer driving conditions and reduce the potential for future deterioration of the road.

With the implementation of Alternative 1, primarily Olivenheim cobbly loam soils would be collectively impacted; however, a majority of the soils have already been disturbed by the existing road and its turnouts and secondary trails. Construction and grading activities would result in short- term, minor, adverse impacts on soil resulting from erosion and sedimentation. Grading activities in more rugged terrain could result in greater potential for soil erosion and sedimentation than in flat terrain. Erosion-and-sediment-control plans would be developed and implemented both during and following road improvements to contain soil and runoff on site and would reduce the potential for adverse effects associated with erosion and sedimentation and transport of sediments in runoff. Once grading activities have subsided, and soils have once again compacted under vehicle weight, soil erosion would be much less likely to occur. Expansion of the road to 24 ft in locations where that standard is not currently met could involve removal of some loose sediment and soil. Improvements to the existing road would permanently impact Olivenheim cobbly loam soils due to road widening.

Maintenance of roads would reduce the effects incurred from negligence, such as rutting, washout, and long-term soil erosion. Proper crowning of the road to manage stormwater runoff would also reduce the potential for soil erosion and sedimentation. Therefore, maintenance of the road would result in a long-term, beneficial impact on soils. Upon completion of the construction of the project, all disturbed areas would be seeded and mulched immediately, thereby further stabilizing the soil.

With the implementation of Alternative 1, soil erosion would decrease, and the integrity of the surrounding soil would be maintained. Loss of soil and topsoil would decrease with the proposed installation of the water bar system. Furthermore, Olivenheim cobbly loam soils are moderately suitable for road-building uses. Therefore, impacts on soils are considered minor and insignificant.

Geologic Hazards. Continued maintenance and repair would be beneficial to reduce the future deterioration of the road and remove debris following a potential geological event. BMPs would be implemented to minimize soil erosion and sedimentation. Alternative 1 would not expose people or structures to substantial adverse geologic hazard effects.

3.3.3.2            Alternative 2: Complete Road Improvement

Regional Geology. Alternative 2 would not expose people or structures to substantial adverse effects or remove a geologic resource. Alternative 2 would not alter rock formations or layering of sedimentary rock. Negligible impacts on geology would be anticipated from the implementation of Alternative 2, which would be similar to, but slightly greater than, impacts resulting from Alternative 1.

Topography. Long-term, negligible, adverse impacts on topography would be anticipated from grading activities that would locally alter existing topography. The majority of areas proposed for grading have been previously graded, and, therefore, impacts would be negligible; however, impacts would be greater than those for Alternative 1 due to improving more than twice the length of road.

Soils. Under Alternative 2, road improvements for the entire 12,983 ft of road would stop further deterioration of road conditions and prevent future erosion of the road surface from occurring. The application of soil stabilizing agents and the construction of water bars would each result in safer driving conditions and reduce the potential for future deterioration of the road. The installation of rip-rap would also further prevent erosion. Impacts on soils under Alternative 2 would be anticipated to be similar to, but greater than, impacts from Alternative 1 due to the larger project area.

With implementation of Alternative 2, primarily Olivenheim cobbly loam soils and San Miguel Exchequer soils would be impacted; however, a majority of the soils have already been disturbed by the existing road and its turnouts and secondary trails. Construction and grading activities would result in short-term, minor, adverse impacts on soil resulting from erosion and sedimentation. Grading activities in more rugged terrain could result in greater potential for soil erosion and sedimentation than in flat terrain. However, erosion-and-sediment-control plans would be developed and implemented both during and following road improvements to reduce the potential for adverse effects associated with erosion and sedimentation and transport of sediments in runoff. Once grading activities have subsided, and soils have once again compacted under vehicle weight, soil erosion and sedimentation into nearby water bodies would be much less likely to occur. Expansion of the road to 24 ft in locations where that standard is not currently met could involve removal of some loose sediment and soil. Improvements to the existing road would permanently impact Olivenheim cobbly loam and Miguel Exchequer soils due to road widening.

Maintenance of roads would reduce the effects incurred from negligence, such as rutting, washout, and long-term soil erosion. Proper crowning of the road to manage stormwater runoff would also reduce the potential for soil erosion and sedimentation. Therefore, maintenance of the road would result in a long-term, beneficial impact on soils. Upon completion of the construction of the project, all disturbed areas would immediately be seeded and mulched.

With the implementation of Alternative 2, soil erosion would decrease, and the integrity of the surrounding soil would be maintained. Loss of soil and topsoil would decrease with the proposed installation of the water bar system. Olivenheim cobbly loam soils are moderately suitable for road-building uses; however, the Miguel Exchequer soils on the southern portion of the road are poorly suited for road-building uses, mainly due to runoff potential and a very high erosion hazard. While impacts on soils would be considered minor and insignificant, the impact from the implementation of Alternative 2 would be greater than impacts from Alternative 1 due to additional maintenance and construction activities on the longer stretch of road.

Geologic Hazards. Alternative 2 would not expose people or structures to substantial adverse geologic hazard effects. The geologic hazard impacts for Alternative 2 would be similar to, or slightly greater than, those described for Alternative 1, due to the larger project area.

3.3.3.3            Alternative 3: Preferred Alternative (Improve Drainage Features Without Widening Road)

Regional Geology. Alternative 3 would not expose people or structures to substantial adverse effects or entirely remove a geologic resource. Alternative 3 would not alter rock formations or layering of sedimentary rock. Negligible impacts on geology would be anticipated from the implementation of Alternative 3.

Topography. Long-term, negligible, adverse impacts on topography would be anticipated from increased erosion and sedimentation that would locally alter existing topography. Although areas proposed for re-grading have been previously graded, impacts on topography would be anticipated to be long-term, negligible, and adverse because existing topography would be locally altered.

Soils. Under Alternative 3, CBP would repair the current two track road and make drainage and other improvements. Because of the lack of formal construction design, FC-4 roadways are subject to greater deterioration than FC-2 roadways if left unmaintained. When subjected to heavier traffic, rutting occurs, which in turn is exacerbated by rain events that further erode the surface.

Maintenance and repair of FC-4 roads such as grading and other ground-disturbing activities would result in erosion and sedimentation. Maintenance of FC-4 roads include filling in potholes and re- grading and compacting road surfaces in areas that have been severely eroded. These activities would result in short- and long-term, minor, adverse impacts on soil resulting from erosion and sedimentation if compaction does not occur during or immediately after the grading process. Grading activities in more rugged terrain could result in greater potential for soil erosion and sedimentation than in flat terrain, increasing the need for immediate compaction.

Unmanaged stormwater flow also causes general erosion to occur, washing out complete sections of road and in many instances making roads impassable. As drainage improvements would be made under this alternative, no short- or long-term, adverse impacts on soils would be expected due to increased erosion potential. Under Alternative 3, impacts on soils would be similar to Alternative 1 due to the implementation of such drainage improvements.

Geologic Hazards. Alternative 3 would not expose people or structures to substantial adverse geologic hazard effects. The geologic hazard impacts would be similar to those described in Alternative 1.

3.3.3.4            No Action Alternative

Under the No Action Alternative, CBP would not be maintaining, repairing, or improving the road. CBP enforcement actions would be maintained at current levels or diminish over time due to inaccessibility of the area to CBP agents. Under this alternative, CBP agents could be exposed to injury in the event of road failure and illegal foot traffic would continue to impact the project area and the Otay Mountain Wilderness.

Under the No Action Alternative, road conditions would continue to deteriorate, resulting in increased soil and sediment erosion. The No Action Alternative could therefore result in greater impacts on soils than Alternatives 1, 2, or 3, due to the greater potential for soil erosion and sedimentation without key maintenance and repair activities to the road.

3.4        VEGETATION

3.4.1           Definition of the Resource

Vegetation includes native or naturalized plants and the habitats in which they exist. This section includes a description of all plants, plant communities, and their habitats occurring within the boundaries of the proposed 1418 Firebreak Road improvement area. This section describes the affected environment, including native and non-native vegetation occurring within the project area. Local special-status or rare vegetation species as defined by California Natural Diversity Database (CNDDB) (CNDDB 2019), San Diego County MSCP, California Native Plant Society Inventory records (CNPS 2019a), and U.S. Department of Agriculture Natural Resource Conservation Service Soil Survey Data (Soil Survey Staff 2019a) are discussed in this section and are considered in the same general manner as the vegetation communities and other plant species discussed in this section and are not analyzed individually by species in this EA. Federal and state threatened, endangered, and candidate plant species are discussed in Section 3.6.

Surveys were conducted from February 2019 through September 2019 to identify suitable habitats for special-status species. The survey area included a 50-foot corridor from the road centerline, totaling a 100-foot wide boundary along the entire length of 1418 Firebreak Road. Habitat conditions observed in the project area were used to evaluate the potential for occurrence of special-status species based on these searches and the professional expertise of the investigating biologists. The potential for each special-status species to occur in the project area was then evaluated according to the following criteria:

• No Potential. Habitat on and adjacent to the site is clearly unsuitable for the species’ requirements. For wildlife, this is based on a lack of one or more essential habitat elements (foraging, breeding, cover, substrate, elevation, hydrology, plant community, site history, disturbance regime). Species surveys are not considered necessary.

• Unlikely. Few of the habitat components meeting the species’ requirements are present, and/or the majority of habitat on and adjacent to the site is unsuitable or of very poor quality. The species is not likely to be found on the site. Species surveys are not considered necessary but could be performed to confirm species absence.

• Moderate Potential. Some of the habitat components meeting the species’ requirements are present, and/or only some of the habitat on or adjacent to the site is unsuitable. The species has a moderate probability of being found on the site. Species surveys could be necessary to determine presence, extent, density, and details of species distribution.
  • High Potential. Most or all of the habitat components meeting the species’ requirements are present and/or most of the habitat on or adjacent to the site is highly suitable. The species has a high probability of being found on the site. If species surveys are not conducted, then it is recommended that the species is assumed to be present. Species surveys could be necessary to determine extent, density, and details of species distribution.

• Present. Species was observed on the site or has been documented recently as being on the site. Focused species surveys could still be needed to determine extent, density, and details of species distribution.

3.4.2           Affected Environment

Two-thousand forty-seven plants species have been documented within San Diego County (Rebman and Simpson 2014). Of these species, 1,689 are native to the county and 758 are non- native and naturalized. A total of 96 plants species were documented within the project area during surveys, including 94 native species.

Vegetation communities were surveyed during biological surveys conducted in spring and September 2019 and described in a biological survey report (CBP 2020). Prior to these surveys, data from the Web Soil Survey (Soil Survey Staff 2019b) and aerial photographs of the site (Google Earth 2019) were examined to determine whether any unique soil types that could support sensitive plant communities and/or aquatic features were present in the project area. Biological communities observed were classified using the National Vegetation Classification System (NVCS). The vegetation was mapped based on existing NVCS plant community descriptions discussed in A Manual of California Vegetation (Sawyer et al. 2009) and A Manual of California Vegetation, Online Edition (CNPS 2019b), NatureServe’s Classification of Ecological Communities (NatureServe 2019), and the Vegetation Classification Manual for Western San Diego County (Sproul et al. 2011). These references describe communities down to the alliance or association level, which are the two most detailed levels of vegetation community classification. Associations are one step more specific than alliances. Vegetation communities within the project area were mapped to the association level, whenever possible.

Vegetation communities found within the project area include Adenostoma fasciculatum- Xylococuus bicolor-Ceanothus tomentosus Association (Chamise chaparral), Bahiopsis lacinata- Artemisia californica-Eriogonium fasciculatum Association (Coastal Sage Scrub), Disturbed Bare Ground, Hesperocyparis forbesii Alliance (Southern Interior Cypress Forest), Mediterranean California Naturalized Annual and Perennial Grassland Semi-Natural Stands (Non-native Grassland/Coastal Sage Scrub), Nassella ssp. Association (Native Grassland), Raphnus sativus Ruderal Forbland (Non-native Grassland) (USNVC 2019; Sproul et al. 2011).

Sensitive biological communities include habitats that fulfill special functions or have special values. Natural communities considered sensitive are those identified in local or regional plans, policies, Habitat Conservation Plans, or regulations by the CDFW. The CDFW ranks sensitive communities as “threatened” or “very threatened” and keeps records of their occurrences in its CNDDB (CDFW 2019). CNDDB vegetation alliances are ranked 1 through 5 based on

NatureServe’s (2018) methodology, with those alliances ranked globally (G) or statewide (S) as 1 through 3.

For the purposes of this EA, any vegetation community that would beconsidered a Tier I or Tier II sensitive community per the San Diego MSCP (County of San Diego 1997) was considered sensitive, regardless of the CDFW ranking. The MSCP uses plant community descriptions described in the A California Flora and Supplement (Munz 1968), and Preliminary Descriptions of the Terrestrial Natural Communities of California (Holland 1986), which are different classification systems that predate alliance- and association-level classifications. A classification conversion crosswalk (CNPS 2019b) was used to convert mapped alliances into the MSCP, which used Munz and Holland classifications to determine sensitivity. If a mapped vegetation community within the project area did not fit into one of the MSCP’s described communities, the CDFW ranking was used to determine sensitivity. Vegetation communities along with their associated CDFW rank, respective acreages within the survey area, and respective acreage in the impact area are summarized in Table 3-3.

Table 3-3. Vegetation Communities Occurring in the Project Area

These vegetation communities vary in species composition and levels of anthropogenic disturbance, from relatively undisturbed chamise chaparral and coastal sage scrub communities throughout the project area, to non-native, grassland-dominated communities along access road edges and at the southern terminus of 1418 Firebreak Road. Vegetation communities were identified during site visits and mapped to the association level where possible using field-verified aerial photographs. In some cases, it is necessary to identify variants of community types or to describe non-vegetated areas that are not described in the literature. The vegetation community

descriptions below are based on conditions observed during the 2019 surveys. Maps of the observed vegetation communities can be found in Appendix G.

Native Vegetation. A total of 11.98 acres of chamise chaparral were mapped across a majority of the project area. Chaparral is generally composed of hard-stemmed shrubs with leathery leaves that avoid desiccation during the dry season (Dudek 2012). Common species in this vegetation community that were observed during the 2019 biological surveys include chamise (Adenostoma fasciculatum), mission manzanita (Xylococcus bicolor), hairy ceanothus (Ceanothus oliganthus), ashy spike-moss (Selaginella cinerascens), and wire-lettuce (Stephanomeria sp.).

The northern and southern extents of the project area contain 4.38 acres of coastal sage scrub. This vegetation community is characterized by soft, low, aromatic shrubs and sub-shrubs characteristically dominated by drought-deciduous species. This community typically occurs on sites with low moisture availability, such as dry slopes and clay-rich soils that are slow to release stored water (Dudek 2012). This land cover type was dominated by San Diego County viguiera (Bahiopsis lacinata), California sagebrush (Artemisia californica), and California buckwheat (Eriogonium fasciculatum), with co-dominant plant species being clustered tarweed (Deinandra fasciculata), coastal goldenbush (Isocoma menziesii), and turkey mullein (Croton setiger).

The project area contains 4.64 acres of disturbed unvegetated areas, which include bare patches of dirt where vegetation is constantly disturbed or removed such that little to no vegetation persists. Disturbed unvegetated areas include all unpaved access roads and areas that are constantly disturbed due to vehicle traffic but are not concrete or gravel roads.

A total of 0.67 acres of southern interior cypress forest were mapped in the project area. This vegetation community is a moderately dense, fire-maintained, low forest. The canopy is open to intermittent, depending on stand age and substrate development, with trees up to 52 feet tall. This vegetation community often occurs as isolated groves within a matrix of chaparral or pinon-juniper woodland. The shrub layer can range from intermittent to continuous, and the herbaceous layer is sparse to intermittent (SDMMP 2010). Common species in this vegetation community that were observed include Tecate cypress (Hesperocyparis forbesii) and chamise with co-dominant plant species being chaparral pea (Pickeringia montana) and San Diego County viguiera (Bahiopsis lacinata).

In the southern portion of the project area, 0.36 acres of native grassland were mapped. Common species in this vegetation community that were observed include purple needle grass (Nassella Stipa sp.), western blue-eyed grass (Sisyrinchium bellum), and clustered tarweed with co-dominant plant species being blue dicks (Dichelostemma capitatum), deerweed (Acmispon glaber), and filaree (Erodium spp.).

Non-Native Vegetation. The middle portion of the project area contains 8.18 acres of non-native grassland/coastal sage scrub. This land cover type was dominated by brome (Bromus ssp.) and wild oats with patches of deerweed, California sagebrush, turkey mullein, and western blue-eyed grass, with additional plant species being San Diego goldenstar (Bloomeria clevelandii), checkerbloom (Sidalcea sp.), and red maids (Calandrinia menziesii).

The project area contains 0.06 acres of non-native grassland mapped in the northernmost portion. This land cover type was dominated by brome, radish (Raphanus sativus), turkey mullein, wire- lettuce, and sow thistle (Sonchus spp.), with co-dominant plant species being checkerbloom, California matchweed (Gutierrezia californica), and red maids.

Local Special Status Vegetation Species. Seven special-status plants were mapped within the project area during survey efforts, and a total of nine additional special-status plant species have been documented to occur within 1 mile of the project area, within the Dulzura, Jamul Mountain, and Otay Mountain USGS 7.5-minute quadrangle maps.

Special-status species include species that are listed as endangered or threated at the federal or state level, CDFW species of special concern, and City of San Diego MSCP-listed species. Seven special-status species are present within the project area, none of which are federally listed species. Otay manzanita (Arctostaphylos otayensis) was observed and mapped within dense chamise chaparral along the middle and southern portions of the project area. San Diego County viguiera (Bahiopsis laciniata) was prolific throughout the project area and could be found along disturbed margins of the road and within open areas associated with coastal sage scrub, chamise chaparral, and southern interior cypress forest. Extensive populations of San Diego goldenstar (Bloomeria clevelandii) were mapped within the central portion of the project area, specifically in open non- native grassland/coastal sage scrub habitat. Western dichondra (Dichondra occidentalis) was found in rocky outcrops within open areas of chamise chaparral habitat towards the southern portion of the project area. Tecate cypress (Hesperocyparis forbesii) formed dense stands within the southern interior cypress forest habitat at the southern terminus of the project area. Munz’s sage (Salvia munzii) favored the ecotone between chamise chaparral and grassland habitats as well as open chamise chaparral throughout the project area. Ashy spike-moss (Selaginella cinerascens) carpeted the understory of the chamise chaparral habitat found throughout the project area.

Rare plant surveys were conducted in the spring and summer of 2019, peak blooming season for perennial herbs and shrubs. No rare plants were observed.

Pesticides. Neither USBP nor its contractors would use herbicides or pesticides for vegetation control for maintenance activities along 1418 Firebreak Road. Therefore, the use of herbicides and pesticides will not be further discussed.

3.4.3           Environmental Consequences

Impacts on vegetation would be considered major and adverse if a large portion of the vegetation community was affected or if the Proposed Action permanently affected the range of a species or population size of a plant community.

3.4.3.1            Alternative 1: Partial Road Improvement

Short- and long-term, negligible to minor, direct and indirect, adverse effects on vegetation would occur from Alternative 1 due to vegetation clearing, crushing, accidental spills, and temporary increases in turbidity and sedimentation. All maintenance and repair activities would occur within or adjacent to the existing footprint of 1418 Firebreak Road.

Long-term, negligible to minor, adverse impacts would occur from the loss of vegetation during road widening since some areas of vegetation would be converted into parts of the improved road. Some portions of land consisting of currently disturbed areas would be converted into turnouts and passing lanes along the roadway. Maintenance activities would also have the potential to generate dust, therefore covering nearby vegetation. This dust could affect photosynthesis, respiration, transpiration and allow for the penetration of pollutants. However, vegetation control would be limited to the existing footprint and immediately surrounding areas where very little vegetation currently grows. Vegetation clearing could include the selective removal of woody vegetation and could have the potential to result in conversion or degradation of habitat.

Negligible to minor, direct, adverse effects on vegetation, such as crushing, could occur when required vehicles and equipment access, park at, and maneuver around areas requiring maintenance. All maintenance activities are expected to occur within or adjacent to existing footprints of the roadway; as such, these impacts would be negligible to minor.

Degradation of plant communities would also occur if petroleum products or other hazardous materials are accidently released during the temporary operation and storage of maintenance and repair vehicles and other equipment.

Under this alternative, a long-term, beneficial impact on erosion and sedimentation would occur from the periodic, scheduled inspections and maintenance of roadway. Beneficial impacts would also be expected from the installation of water bars, which would result in the reduced potential for erosion and sedimentation. Adverse impacts on vegetation would be minimized by using appropriate BMPs (see Appendix D).

3.4.3.2            Alternative 2: Complete Road Improvement

Short- and long-term, negligible to minor, direct and indirect, adverse effects on vegetation would occur from Alternative 2 due to vegetation clearing, crushing, accidental spills, and temporary increases in turbidity and sedimentation. Impacts from Alternative 2 would be expected to be greater than those from Alternative 1 due to the additional 8,098 ft of roadway slated for improvement. As with Alternative 1, all maintenance and repair activities would occur within or adjacent to the existing footprint of 1418 Firebreak Road.

The likelihood of an accidental spill of petroleum products or other hazardous materials during the operation or storage of maintenance and repair vehicles would be greater with Alternative 2 than Alternative 1, which could lead to further degradation of plant communities. However, all regulatory requirements for handling and storage of fuels, oils, and other hazardous materials would be implemented.

Under this alternative, a long-term, beneficial impact on erosion and sedimentation would occur from the periodic, scheduled inspections and maintenance of roadway. Beneficial impacts of Alternative 2 would be greater than those of Alternative 1 due to the additional 8,098 ft of roadway slated for improvement. Adverse impacts on vegetation would be minimized by using appropriate BMPs (see Appendix D).

3.4.3.3            Alternative 3: Preferred Alternative (Improve Drainage Features Without Widening Road)

Under Alternative 3, short- and long-term, negligible, direct and indirect, adverse effects on vegetation would occur. All maintenance and repair activities would occur within the existing footprint of 1418 Firebreak Road. Maintenance and repair under this alternative would result in impacts on vegetation, such as the accidental release of petroleum products or other hazardous materials, trampling and crushing vegetation while accessing the site, and increased erosion, turbidity, and sedimentation. Impacts associated with the implementation of Alternative 3 would be expected to be similar to those of Alternative 1.

3.4.3.4            Alternative 4: No Action Alternative

Under the No Action Alternative, CBP would not be maintaining, repairing, and improving the road. CBP enforcement actions would be maintained at current levels or diminish over time due to inaccessibility of the area to CBP agents. Therefore, no impacts on vegetation would be expected from the implementation of the No Action Alternative because no maintenance or repair activities would occur in the project area.

3.5        TERRESTRIAL AND AQUATIC WILDLIFE RESOURCES

3.5.1           Definition of the Resource

Terrestrial and aquatic wildlife resources include native or naturalized terrestrial and aquatic animals and the habitats in which they exist. This section includes a description of terrestrial and aquatic wildlife species and their habitats that are likely to be found in the project area. Local special status or rare wildlife species as defined by CNDDB, MSCP, San Diego County Bird Atlas (Unitt 2004), and San Diego County Mammal Atlas (Tremor et al. 2017) are discussed in this section. Federally listed threatened, endangered, and candidate species and California state-listed threatened and endangered wildlife species are addressed in Section 3.6.

This section is supported by data gathered during biological surveys conducted from February 2019 through September 2019, and the associated biological survey report (CBP 2020).

3.5.2           Affected Environment

Terrestrial Resources. The proposed project area is capable of supporting various wildlife species, including mammals, birds, reptiles, and amphibians.

One hundred and twelve species of mammals have been documented in San Diego County (Tremor et al. 2017). During biological surveys, only one special-status mammal species, the southern mule deer (Odocoileus hemionus), was observed. Southern mule deer are found throughout San Diego County in habitats providing proximity to water and a wide selection of forage. This MSCP species is impacted by a lack of wildlife corridors and has a high potential to occur on site. One additional special-status mammal has a moderate potential to occur within the project area, the Bryant’s woodrat (Neotoma bryanti). The Bryant’s woodrat uses bases of shrubs, cacti, or rock crevices for nesting structures and prefers areas with succulent vegetation for forage, habitat that is abundant in the project area.

Five hundred and twenty-one species of bird have been documented in San Diego County (Unitt 2004). Many of these are migratory birds that do not nest in the area, but still rely on stop over locations to feed and rest during their migration. Seven special-status bird species were documented within the project area during recent surveys: the Northern harrier (Circus cyaneus), least Bell’s vireo (Vireo bellii pusillus), California horned lark (Eremophila alpestris actis), coastal California gnatcatcher (Polioptila californica californica), Southern California rufous-crowned sparrow (Aimophila ruficeps canescens), black-chinned sparrow (Spizella atrogularis), and grasshopper sparrow (Ammodramus savannarum).

One special-status bird species, the white-tailed kite (Elanus leucurus), has a moderate potential to occur within 1 mile of the project area. White-tailed kite require open habitats with adequate vegetative structure to support prey animals, which include grasslands, savannah, woodlands, and wetlands. This species prefers edge habitat with tree structure for nesting with no preference for a specific land cover type. Suitable foraging habitat for this species exists within the open grassland and coastal sage scrub in the project area.

Seventy-nine species of reptiles and amphibians have been documented in San Diego County (SDNHM 2017). During biological surveys, only one special-status reptile species was observed, the San Diegan tiger whiptail (Aspidoscelis tigris stejnegeri). In addition, one amphibian and two reptile special-status species have high potential to occur within the project area including the Western spadefoot (Spea hammondii), coast horned lizard (Phrynosoma blainvillii), and red diamond rattlesnake (Crotalus ruber). Meanwhile, four special-status reptile species have moderate potential to occur within the project area including the Southern California legless lizard (Anniella stebbinsi), orange-throated whiptail (Aspisdoscelis hyperythra beldingi), coast patch-nosed Snake (Salvadora hexalepis virgultea), and two-striped garter snake (Thamnophis hammondii).

Aquatic Resources. No special-status aquatic wildlife, including native or naturalized fish, mollusks, and crustaceans, was identified in the 2019 surveys. However, the project area does contain 14 road pools that have potential suitable habitat for both San Diego fairy shrimp (Branchinecta sandiegonensis) and Riverside fairy shrimp (Streptocephalus woottoni). Four of these road pools were found to be occupied by San Diego fairy shrimp during 2019 surveys. Impacts on fairy shrimp are discussed further in Section 3.6. No impacts on aquatic resources would be anticipated; therefore, they are not discussed further.

3.5.3           Environmental Consequences

Effects on wildlife would be major and adverse if the species or habitats are adversely affected over relatively large areas. Effects would also be considered significant if disturbances cause substantial or permanent reductions in population size or distribution of a species.

3.5.3.1            Alternative 1: Partial Road Improvement

Short- and long-term, negligible to minor, direct and indirect, adverse effects on wildlife would occur from implementation of Alternative 1. All maintenance and repair activities would occur within or adjacent to the existing footprint of 1418 Firebreak Road. As such, maintenance and repair of the roadway would result in temporary, minor degradation of wildlife habitat and a small amount of permanent habitat loss.

Mechanical vegetation clearing, such as mowing and trimming, could cause larger mammals, reptiles, and birds, including breeding migratory birds, to temporarily relocate. Individuals of smaller, less-mobile species could inadvertently be directly impacted by maintenance and repair activities. Vegetation control would occur within the existing footprint where vegetation is being maintained. As such, impacts from vegetation control would be temporary. The direct disturbance of habitat associated with vegetation clearing, including the selective removal of woody plants, could result in the establishment of invasive plant species in the cleared area resulting in the conversion of habitat.

Localized degradation of habitat would also occur if petroleum products or other hazardous materials are accidently released during operation or storage of maintenance vehicles and other equipment. However, all regulatory requirements for handling and storage of fuels, oils, and other hazardous materials (such as the development of spill prevention plans) would be implemented. Thus, habitat degradation resulting from accidental releases of hazardous materials would be negligible.

Some wildlife might be killed or injured during ground-disturbing activities or during transportation of equipment and personnel. Ground-disturbing activities would occur within or adjacent to the existing footprint, potentially resulting in animals being killed or injured during planned activities. Burrowing animals, such as the rodents and reptiles, could also be impacted.

Temporary displacement of mobile wildlife from noise and other disturbances associated with Alternative 1 would occur. However, adverse impacts would be minimized by using appropriate BMPs (see Appendix D).

3.5.3.2            Alternative 2: Complete Road Improvement

Short- and long-term, negligible to minor, direct and indirect, adverse effects on wildlife would occur from the implementation of Alternative 2. Wildlife could be killed or injured during ground- disturbing activities or during transportation of equipment and personnel. Temporary displacement of mobile wildlife from noise and other disturbances could also be associated with this alternative. As a result, wildlife impacts associated with Alternative 2 would be greater than those associated with Alternative 1 due to the extended construction period and increased distance that accompanies complete road improvement. As with Alternative 1, all maintenance and repair activities would occur within or adjacent to the existing roadway footprint, yet such activities would still result in temporary, minor degradation of wildlife habitat and a small amount of permanent habitat loss.

As with Alternative 1, mechanical vegetation clearing could cause larger mammals, reptiles, and birds to temporarily relocate and individuals of smaller, less-mobile species to be inadvertently directly impacted. In addition, vegetation clearing could result in the establishment of invasive plant species in the cleared area resulting in the habitat conversion. Impacts under Alternative 2 would be greater than those of Alternative 1 due to the extended project area that accompanies complete road improvement.

The likelihood of an accidental spill of petroleum products or other hazardous materials during the operation or storage of maintenance and repair vehicles would be greater with Alternative 2 than Alternative 1 and could lead to localized habitat degradation. All regulatory requirements for

handling and storage of fuels, oils, and other hazardous materials (such as the development of spill prevention plans) would be implemented. Thus, habitat degradation resulting from accidental releases of hazardous materials would be negligible. BMPs would be implemented to further minimize these adverse effects.

3.5.3.3            Alternative 3: Preferred Alternative (Improve Drainage Features Without Widening Road)

Under Alternative 3, short- and long-term, negligible to minor, direct and indirect, adverse effects on terrestrial wildlife would occur. All maintenance and repair activities would occur within the existing footprint of 1418 Firebreak Road. Under this alternative, impacts on wildlife, such as displacement of wildlife, habitat conversion, and degradation from vegetation clearing and the accidental release of petroleum products; crushing of smaller, less-mobile species resulting in death or injury; and disturbance from noise effects and temporary displacement of terrestrial species would be expected. Impacts associated with the implementation of Alternative 3 would be expected to be similar to those of Alternative 1.

3.5.3.4            Alternative 4: No Action Alternative

Under the No Action Alternative, CBP would not be maintaining, repairing, and improving the road. Therefore, no impacts on terrestrial wildlife would be expected from the implementation of the No Action Alternative because no maintenance or repair activities would occur in the project area. Under this alternative, traffic on the road would continue as normal and it is unlikely that any other entity would maintain the road.

3.6        THREATENED AND ENDANGERED SPECIES

3.6.1           Definition of the Resource

Threatened and endangered species are commonly protected because their historic range and habitat have been reduced and will only support a small number of individuals. Some species have declined for natural reasons, but declines are commonly exacerbated or accelerated by anthropogenic influences. Anthropogenic influences that have contributed to reduced range and habitat availability and reduced populations include agriculture, livestock grazing, urban development and road construction, overcollection, trampling and off-road vehicle use, hydrologic modifications, and altered fire regimes. Once natural vegetation and habitat are disturbed, introduced species can colonize more readily and out-compete native species. Some species occupy specific niches, so even minor alterations are not well-tolerated.

Species listed as threatened or endangered under the ESA (federally listed species) and California ESA, as well as designated critical habitat that have the potential to be affected, are discussed in this section. A list of potential threatened, endangered, or candidate species was compiled from USFWS and CDFW. USFWS is responsible for maintaining and tracking a list of federal threatened, endangered, and candidate species. CDFW is responsible for maintaining a similar list of species for the State of California. In terms of protection and habitat suitability, any species listed as a federal or state candidate is assessed in a manner as though it has already been listed threatened or endangered. This section presents those federal- and state-listed species that are known to occur or have the potential to occur within the project area.

Consultation with USFWS began in the spring of 2019 with the Notice of Preparation for an EA for the project. USFWS responded with by identifying potential project impacts to the San Diego refuge, and federally listed species and their critical habitats. Consultation with USFWS was formally requested in September 2020 for the San Diego fairy shrimp, Quino checkerspot butterfly, Least Bell’s vireo, and California gnatcatcher with the submission of the project Biological Assessment.

In early 2021, USFWS identified potential impacts to Riverside fairy shrimp as part of the project restoration component and requested the addition of the species to the consultation process. A formal request for consultation for Riverside fairy shrimp was issued in February 2021. A final Biological Opinion for San Diego and Riverside fairy shrimp was dated May 26, 2021. Quino checkerspot butterfly, Least Bell’s vireo, and California gnatcatcher were addressed under informal consultation.

3.6.2           Affected Environment

Following biological surveys, it was determined that four federally listed species, the Quino checkerspot butterfly (Euphydryas editha quino), coastal California gnatcatcher (Polioptila californica californica), least Bell’s vireo (Vireo bellii pusillus), and San Diego fairy shrimp (Branchinecta sandiegonensis), are known to occur within or adjacent to the project area. The coastal California gnatcatcher and Quino checkerspot butterfly occur primarily within the chaparral habitats of the project area, which is atypical for both species. The least Bell’s vireo was observed northwest of the project area within riparian woodland habitat. It is expected that the entire project area contains potential habitat for the Quino checkerspot butterfly and coastal California gnatcatcher. These federally listed species are not uniformly distributed among the project area but instead concentrated in areas with preferable habitat.

Three species have critical habitat that overlaps the project area. Least Bell’s vireo mapped critical habitat is at the northernmost terminus of 1418 Firebreak Road, at the intersection with Otay Lakes Road. However, while critical habitat overlaps the project area, no riparian habitat used by least Bell’s vireo was observed within the project area. Coastal California gnatcatcher mapped critical habitat is found along the northern portion of 1418 Firebreak Road from the intersection with Otay Lakes Road and continues south approximately 1 mile. Approximately 2.13 acres of coastal California gnatcatcher critical habitat is found within the project area. Quino checkerspot butterfly mapped critical habitat encompasses the northern terminus and middle section of 1418 Firebreak Road, for a total of approximately 1 mile. Approximately 4.64 acres of Quino checkerspot butterfly critical habitat is found within the project area. Figure 3-1 depicts all critical habitat within the project area.

3.6.2.1            Terrestrial Threatened and Endangered Species

Quino checkerspot butterfly. The Quino checkerspot butterfly is a small butterfly in the brush- footed butterfly family (Nymphalidae). The species is one of at least 18 California subspecies of the more widespread Edith’s checkerspot. Adults fly once per year from late February to mid-April. Threats to the Quino checkerspot include agriculture and urban development, conversion of native habitats, fire management practices, and grazing.

Historically, the Quino checkerspot butterfly was found from the Santa Monica Mountains south into northern Baja California. The Quino checkerspot butterfly is found in areas with open canopies of coastal sage scrub, open chaparral, juniper woodland, and native grasslands. The species habitat contains open areas and low-growing, sparse vegetation, with a low to moderate amount of non- native species (USFWS 2003). Food plants used by Quino checkerspot larva is restricted to dot- seed plantain (Plantago erecta), wooly plantain (P. patagonica), possibly desert Indianwheat (P. ovata), purple owl’s clover (Castilleja exserta), Coulter’s snapdragon (Antirrhinum coulterianum), bird’s beak (Cordylanthus rigidus), and Chinese houses (Collinsia spp.) (USFWS 2003, Mattoni et al. 1997).

There is suitable habitat for the Quino checkerspot butterfly within the project area, because there are habitats with appropriate structure, species makeup, and host plants present within the surrounding area. During the 2019 surveys, a total of 25 Quino checkerspot butterflies were observed in or around the project area.

Figure 3-1. Critical Habitat

The following measures  would be implemented to minimize impacts to Quino checkerspot butterflies:

1. CBP would staff a biologist, approved by USFWS, who would be responsible for monitoring and reporting compliance with avoidance and minimization measures for biological resources during work activities addressed in the biological opinion. The biologist must be knowledgeable of Quino checkerspot butterfly biology and ecology. The biologist would perform the following duties:

1. Be on site during all vegetation clearing/grubbing and project construction within 500 feet of habitat to be avoided.

1. Oversee installation of and inspect the fencing and erosion control measures a minimum of once per week and daily during all rain events to ensure that any breaks in the fence or erosion control measures are repaired immediately.

1. Conduct Quino checkerspot butterfly and host plant surveys in the impact area within one week prior to impacts. If found, host plants would be flagged and avoided to the maximum extent practicable. If host plants cannot be avoided, CBP would contact USFWS for further consultation.

1. Periodically monitor the work area to ensure that work activities do not generate excessive amounts of dust.

1. Train all contractors and construction personnel on the biological resources associated with this project and ensure that training is implemented by construction personnel. At a minimum, training would include: (i) the purpose for resource protection; (ii) a description of the sensitive species found on site and their habitat(s); (iii) the conservation measures that should be implemented during project construction to conserve sensitive species, including strictly limiting activities, vehicles, equipment, and construction materials to the project area to avoid sensitive resource areas in the field (i.e., avoided areas delineated on maps or on the project site by fencing); (iv) environmentally responsible construction practices; (v) the protocol to resolve conflicts that may arise at any time during the construction process; (vi) the general provisions of the ESA, the need to adhere to the provisions of the ESA, and the penalties associated with violating the ESA.

1. Halt work, if necessary, and confer with USFWS to ensure the proper implementation of species and habitat protection measures. The biologist would report any violation to USFWS within 24 hours of its occurrence.

1. Submit weekly email reports to USFWS during vegetation clearing and/or project construction. These weekly reports would document that authorized impacts were not exceeded and general compliance with all conditions. The reports would also outline the duration of monitoring, the location of construction activities, the type of construction which occurred, and equipment used. These reports would specify numbers, locations, and sex of sensitive species observed and remedial measures

employed to avoid, minimize, and mitigate impacts to sensitive species. Raw field notes should be available upon request by USFWS.

1. Submit a final report to USFWS within 60 days of project completion that includes as-built construction drawings with an overlay of habitat that was impacted and avoided, photographs of habitat areas that were to be avoided, and other relevant summary information documenting that authorized impacts were not exceeded and that general compliance with all conditions of this consultation was achieved.

1. Offset impacts to 1.43 acres of Quino checkerspot butterfly critical habitat, including 0.02 acre of coastal sage scrub/chamise chaparral gnatcatcher habitat, 0.0012 acres of which is gnatcatcher critical habitat with physical or biological features, by closing 2.32 acres of unauthorized roads in the vicinity of 1418 Firebreak Road and restoring/enhancing the area for Quino checkerspot butterfly/gnatcatcher habitat. In addition, CBP would place reflective delineating markers where vegetation does not delineate the 10-foot-wide roadbed in order to discourage use and allow passive vegetation restoration of the areas outside of the 10-foot-wide roadbed.

1. Project construction and maintenance would occur outside the Quino checkerspot butterfly reproduction season, December 1 to May 31.

1. CBP would submit a habitat restoration plan to USFWS for review and approval prior to initiating project impacts and would include the following information and conditions:

1. All specifications and topographic-based grading, planting, and irrigation plans. Topsoil and plant materials salvaged from the habitat areas to be impacted would be transplanted to, and/or used as a seed/cutting source for, the habitat restoration areas to the maximum extent practicable as approved by USFWS. Planting and irrigation would not be installed until USFWS has approved of upland habitat restoration site grading. All plantings would be installed in a way that mimics natural plant distribution. Planting would include pockets of coastal sage scrub surrounded by more herbaceous annuals associated with Quino checkerspot butterfly habitat.

1. Planting palettes (plant species, size, and number/acre) and seed mix (plant species and pounds/acre). The plant palettes would include Quino checkerspot butterfly host and nectar plants, other native annuals, and limited coastal sage scrub species. Seed would be collected from existing plants on site as much as possible. Unless otherwise approved by USFWS, only locally native species (no cultivars) obtained from as close to the project area as possible would be used. The source and proof of local origin of all plant material and seed would be provided.

1. An implementation schedule that indicates when all restoration grading, planting, and irrigation would begin and end. Upland habitat restoration grading, planting, and irrigation would be completed during the concurrent or next planting season (i.e., late fall to early spring) after finishing grading within the restoration area. Any temporal loss of upland habitat caused by delays in restoration would be offset

through upland habitat restoration at a 0.5:1 ratio for every 6 months of delay (i.e., 1:1 for 12 months delay, 1.5:1 for 18 months delay, etc.). If CBP is wholly or partly prevented from performing obligations under the final plans (causing temporal losses due to delays) because of unforeseeable circumstances or causes beyond their reasonable control, and without the fault or negligence of CBP, CBP would be excused by such unforeseeable cause(s).

1. Restoration maintenance would be conducted outside the Quino checkerspot butterfly and gnatcatcher reproduction seasons (December 1 to August 31). If maintenance is needed between December 1 and May 31, a Quino checkerspot butterfly permitted biologist would conduct host plants surveys within the maintenance area within one week prior to work. If found, host plants would be flagged and avoided. If maintenance is necessary between February 15 and August 31, a biologist would survey for gnatcatchers within the maintenance area. Surveys would consist of three visits within one week prior to work and one survey would be conducted the day immediately prior to the initiation of work. Work would be allowed to continue on site during the survey period. However, if gnatcatchers are found during any of the visits, CBP would notify and coordinate with USFWS to identify measures to avoid and/or minimize effects to the gnatcatcher (e.g., nests and an appropriate buffer would be flagged by the biologist and avoided by the maintenance work).

1. Five years of success criteria for restoration areas including: a total of no more than 20 percent absolute cover of coastal sage scrub shrub species, evidence of natural recruitment of multiple species, 0 percent coverage for Cal-IPC List A and B species, and no more than 10 percent coverage for other exotic/weed species.

1. A qualitative and quantitative vegetation monitoring plan with a map of proposed sampling locations. Photo points would be used for qualitative monitoring and stratified-random sampling would be used for all quantitative.

1. Contingency measures in the event of restoration failure.

1. Annual mitigation maintenance and monitoring reports would be submitted to USFWS after the maintenance and monitoring period and no later than December 1 of each year.

Coastal California gnatcatcher. The coastal California gnatcatcher has a limited range within the United States. This subspecies is restricted to coastal Southern California and northwestern Baja California, Mexico, from Ventura and San Bernardino counties, California, south to approximately El Rosario, Mexico (American Ornithologists’ Union 1957, Atwood 1991, Garrett and Dunn 1981). The subspecies exists predominantly in Southern California’s coastal sage scrub habitat, with a strong preference towards areas dominated by California sagebrush (Artemisia californica), chaparral broom (Baccharis sarothroides), and California buckwheat (Eriogonum fasciculatum). The majority of plant species found in coastal sage scrub habitat are low-growing, drought deciduous shrubs and sub-shrubs (USFWS 1997). Densities are highest along sage scrub-grassland borders or in relatively open sage scrub habitat. Nesting occurs in a variety of host shrub species,

with a high depredation rate, which results in frequent replacement clutches throughout the breeding season. The coastal California gnatcatcher is non-migratory (Unitt 2004) and generally avoids crossing even small areas of unsuitable habitat (Atwood and Bolsinger 1992). The species is typically observed on dry coastal slopes, washes, and mesas, in areas with low plant growth of approximately 1 meter (3 ft.) in height (NatureServe 2019). These areas such as in this project footprint can also include low-growing chaparral instead of the more common coastal sage scrub association.

The project area contains suitable coastal sage scrub habitat, dominated by California sagebrush and flat-top buckwheat. During the spring 2019 surveys, multiple coastal California gnatcatchers were detected within the region of analysis, but not within the coastal sage scrub areas. Instead, both observations were within or along the edge of the low growing chaparral areas. This species occurs within the project area and was observed during the 2019 surveys. There is critical habitat for the coastal California gnatcatcher in the northern portion of the project area.

The following measures would be implemented to minimize impacts to coastal California gnatcatchers:

1. A biologist approved by USFWS would be onsite during the initial clearing/grubbing of coastal sage scrub/chamise chaparral and project construction within 500 feet of least Bell’s vireo and coastal California gnatcatcher habitat to ensure compliance with applicable mitigation measures. The biologist must be knowledgeable of least Bell’s vireo and coastal California gnatcatcher biology and ecology. The biologist would perform the following duties:

1. Perform a minimum of three focused surveys, on separate days, to determine the presence of coastal California gnatcatchers in the disturbance area outside the coastal California gnatcatcher breeding season. Surveys would begin a maximum of 7 days prior to performing initial clearing/grubbing of coastal sage scrub/chamise chaparral and one survey would be conducted the day immediately prior to the initiation of clearing/grubbing. If any coastal California gnatcatchers are found within the disturbance area, the biologist would direct construction personnel to begin clearing/grubbing in an area away from the coastal California gnatcatchers. It would be the responsibility of the biologist to ensure that coastal California gnatcatchers are not in the area to be cleared/grubbed. The biologist would also record the number and location of coastal California gnatcatchers disturbed by clearing/grubbing. CBP would notify USFWS at least 7 days prior to clearing/grubbing to allow USFWS to coordinate with the biologist on bird flushing activities.

1. If project construction or maintenance is necessary during the least Bell’s vireo and coastal California gnatcatcher breeding seasons, the biologist would perform a minimum of three focused surveys, on separate days, to determine the presence of least Bell’s vireo and coastal California gnatcatcher nest building activities, egg incubation activities, or brood rearing activities in, or within, 500 feet of these areas. The surveys would begin a maximum of 7 days prior to project construction and one survey would be conducted the day immediately prior to the initiation of work.

Additional surveys would be done once a week during project construction in the breeding season. These additional surveys may be suspended as approved by USFWS. CBP would notify USFWS at least 7 days prior to the initiation of surveys, and within 24 hours of locating any least Bell’s vireos or coastal California gnatcatchers.

1. If a least Bell’s vireo or coastal California gnatcatcher nest is found in or within 500 feet of project construction or maintenance, the biologist would postpone work within 500 feet of the nest and contact USFWS to discuss: (i) the best approach to avoid/minimize impacts to nesting birds (e.g., sound walls); and (ii) a nest monitoring program acceptable to USFWS. Subsequent to these discussions, work may be initiated subject to implementation of the agreed upon avoidance/minimization approach and nest monitoring program. Nest success or failure would be established by regular and frequent trips to the site, as determined by the biologist and through a schedule approved by USFWS. The biologist would determine whether bird activity is being disrupted. If the biologist determines that bird activity is being disrupted, CBP would stop work and coordinate with USFWS to review the avoidance/minimization approach. Coordination between CBP and USFWS to review the avoidance/minimization approach would occur within 48 hours. Upon agreement as to the necessary revisions to the avoidance/minimization approach, work may resume subject to the revisions and continued nest monitoring. Nest monitoring would continue until fledglings have dispersed or the nest has been determined to be a failure, as approved by USFWS.

1. If a nest is found, established either an 8-foot-tall plywood sound wall as far from the nest as possible, but no less than 50 feet between construction and the nest, or conduct sound analysis and monitoring to demonstrate that noise does not exceed 60 Db sustained for an hour at the nest site during project activities.

1. Avoid impacts to areas of perennial vegetation to the extent practicable. Where vegetation impacts cannot be avoided salvage overstory shrubs and stockpile the top 6 inches of topsoil and any grubbed vegetation stockpiled to assist in revegetation.

1. For permanent impacts to coastal California gnatcatcher habitat as a result of the Proposed Action, a mitigation ration of 2:1 has been proposed to address impacts, achieved through restoration of 0.1-acre of coastal sage scrub habitat within disturbed roadways identified by USFWS.

1. Initial clearing/grubbing of coastal sage scrub/chamise chaparral, and project construction and maintenance within 500 feet of least Bell’s vireo and coastal California gnatcatcher suitable habitat, would occur between September 16 and February 14 to avoid the least Bell’s vireo and coastal California gnatcatcher breeding seasons (or sooner if surveys determine that all nesting is complete). If project construction or maintenance are necessary between February 15 and August 31, CBP would conduct least Bell’s vireo and coastal California gnatcatcher nest surveys/monitoring.

Least Bell’s vireo. This subspecies of Bell’s vireo is a neotropical migrant and summer resident in California and northern Baja California, wintering in southern Baja California (Brown 1993). This vireo was once common in lowland riparian habitats throughout California but declined precipitously during the 20th Century. By the time of federal listing in 1986, an estimated 300 pairs were restricted to Southern California, primarily in San Diego County (USFWS 1998). The population has increased since, with the number of nesting territories in California in 2006 estimated to be approximately 10 times greater than in 1986. However, the distribution of the vireo at that time remained almost entirely within Southern California (USFWS 2006).

Least Bell’s vireo breeding habitat consists of riparian vegetation, usually in an early successional state, between 5 and 10 years old. Such habitat is preferred by least Bell’s vireo because it provides dense cover in the lower shrub layer for nest concealment, as well as a stratified canopy structure favorable to insect abundance, and thus vireo foraging. Riparian habitat types used for breeding include those dominated by willows (Salix sp.), Fremont’s cottonwood (Populus fremontii), and/or oaks (Quercus sp.), with a dense understory of species, such as willows, mulefat (Baccharis salicifolia), California wild rose (Rosa californica), poison oak (Toxicodendron diversilobum), and mugwort (Artemisia douglasiana) (USFWS 1998). Nests are typically placed within 3 ft of the ground. Least Bell’s vireo could attempt multiple broods during the breeding season from mid- March to late September, although one brood is typical (Brown 1993). Habitats such as chaparral and coastal sage scrub adjacent to riparian areas are used for foraging and even nesting, and thus provide another potentially important habitat component (Kus and Miner 1989). Along with habitat destruction, brood parasitism by the brown-headed cowbird (Molothrus ater) is widely considered a major contributor to the decline of least Bell’s vireo, and a continuing challenge to its recovery.

The project area does not contain suitable nesting or foraging riparian habitat for least Bell’s vireo, and none have been detected immediately within the project area during survey efforts. However, occupied habitat for this species does exist nearby, within the Otay River Riparian corridor approximately 100 ft north of the northern terminus of the project area. This species does not occur within the project survey area but was heard by surveyors in the riparian areas described.

3.6.2.2            Aquatic Threatened and Endangered Species

San Diego fairy shrimp. San Diego fairy shrimp are small aquatic invertebrates, generally restricted to vernal pools and other ephemeral basins within coastal Southern California coastal sage scrub and chaparral upland habitat. Claypan and hardpan pools provide suitable pools, which generally fill for a short time in the winter and are dry in the summer (Eriksen and Belk 1999). The San Diego fairy shrimp is a habitat specialist that is found in shallower pools up to 12 inches deep. Fairy shrimp feed on a variety of algae, diatoms, and particulate organic matter (USFWS 2007). San Diego fairy shrimp hatch following rainfall in suitable vernal pool habitat and mature within 7–14 days. Individuals are usually seen from January to March, although observations of the species could fall outside this range during early or late rainfall events. Cysts of the species can withstand prolonged dry periods and often form cyst banks in pool soils. These cyst banks allow for the recolonization of habitat in subsequent years (USFWS 2007).

San Diego fairy shrimp was described as a species in 1993 (Fugate 1993). Critical habitat for San Diego fairy shrimp was designated on December 12, 2007 (USFWS 2007). The species is currently

covered under the Vernal Pools of Southern California Recovery Plan issued on September 3, 1998.

The project area falls within the known range of San Diego fairy shrimp, and while there are no vernal pools within the surrounding areas, there are road pools in the access road that could have ponding long enough for fairy shrimp from nearby pools to colonize and use. No critical habitat for the species is within the project area. During biological surveys, San Diego fairy shrimp were observed in ephemeral basins (roadside pools of water) within low areas of 1418 Firebreak Road. Protocol fairy shrimp surveys are complete for the 2020 winter/spring season.

The following measures would be implemented to minimize impacts to San Diego fairy shrimp:

1. CBP would staff a biologist during the vernal pool restoration/enhancement who would be responsible for overseeing compliance with the mitigation measures and would be approved by USFWS. The biologist must be knowledgeable of fairy shrimp and vernal pool biology/ecology. The biologist would perform the following duties:

1. Be on site during work and/or grading to ensure compliance with all mitigation measures.

1. Oversee the installation and inspection of the project perimeter marking and erosion BMPs a minimum of once per week and daily during all rain events to ensure that any breaks in the fence or erosion control measures are repaired immediately.

1. Periodically monitor the work area to ensure that work activities do not generate excessive amounts of dust.

1. Allow salvage of live plants and collection of inoculum for transplant to pools, watersheds and surrounding uplands to be restored/enhanced as practicable and approved by USFWS.

1. Train all contractors and construction personnel on the biological resources associated with this project and ensure that training is implemented by construction personnel. At a minimum, training would include: (i) the purpose for resource protection; (ii) a description of the fairy shrimp and its habitat; (iii) the conservation measures given in the biological opinion that should be implemented during project construction to avoid and/or minimize impacts to the fairy shrimp; including strictly limiting activities, vehicles, equipment, and construction materials to the marked project footprint to avoid sensitive resource areas in the field (i.e., avoided areas delineated on maps or on the project site by fencing); (iv) the protocol to resolve conflicts that may arise any time during the construction process; and (v) the general provisions of the ESA, the need to adhere to the provisions of the ESA, and the penalties associated with non-compliance with the ESA.

1. Halt work, if necessary, for any project activities that are not in compliance with the conservation measures committed to as part of the project and specified in this biological opinion. The biologist would report any non-compliance issues to USFWS within 24 hours of its occurrence and confer with USFWS to ensure the proper implementation of species and habitat protection measures.

1. Submit a final report to USFWS within 60 days of project completion that includes as-built construction drawings showing restored pools, photographs of the restored pools and uplands, and other relevant information documenting compliance with the mitigation measures.

1. Offset impacts to a 0.004-acre road pool occupied by San Diego fairy shrimp in coordination with the Persistent Surveillance and Detection System Improvements Project by restoring 0.012 acre of new vernal pools occupied by San Diego fairy shrimp and enhance the existing vernal pools/uplands such that existing vernal pools and upland areas help to contribute to the success of vernal pool restoration at the Arnie’s Point property on Otay Mesa.

1. Prior to initiating vernal pool restoration, CBP would temporarily mark the limits of restoration impacts (including staging areas and access routes) and install BMPs (e.g., straw wattles, silt fencing, jute cloth) to prevent additional impacts and the spread of silt into extant vernal pools. No restoration activities, materials, or equipment would be permitted outside the marked project footprint. CBP would submit to USFWS for approval, at least 7 days prior to initiating project construction, final construction plans that include photographs of the marked limits of impact, BMPs, and all areas to be impacted or avoided. If work occurs beyond the marked limits of impact, all work would cease until the problem has been remedied to the satisfaction of USFWS. Temporary construction marking would be removed upon project completion.

1. CBP would develop a vernal pool restoration/enhancement plan concurrently with the onset of project impacts and in coordination with the Persistent Surveillance and Detection System Improvements Project. CBP would submit final vernal pool restoration/enhancement plans to USFWS for approval. The restoration/enhancement would not begin until USFWS approves of the final plans. The restoration/enhancement plans would include the following information and measures:

1. All restoration/enhancement activities would commence the first summer-fall season after the initiation of project impacts.

1. All final specifications and topographic-based grading, planting, and watering plans for the vernal pools, watersheds, and surrounding uplands (including adjacent mima mounds) at the restoration sites. Grading plans would have 0.5-foot contours. Vernal pool size and depth would be similar to extant pools closest to the restoration area. The grading plans would also show the watersheds of extant vernal pools, and overflow pathways that hydrologically connect the restored pools in a way that mimics natural vernal pool complex topography/hydrology.

1. A hydraulic analysis that shows each proposed vernal pool and its watershed, the vernal pool to watershed ratio, and hydrologic connection between the pools. The vernal pool to watershed ratio would be similar to extant pools closest to the restoration area. Restored pools and their watersheds would not impact the watersheds of any extant pools except where needed to establish hydrologic connections.

1. A final implementation schedule that indicates when vernal pool restoration grading and planting would begin and end.

1. Native plants and animals would be established within the restored/enhanced pools, their watersheds, and surrounding uplands. This can be accomplished by redistributing topsoil containing seeds, spores, bulbs, eggs, and other propagules from affected pools and adjacent vernal pools and upland habitats; by the translocation of propagules of individual species; and by the use of commercially available native plant species. Any vernal pool inoculum or plant material from an off-site source must be approved by USFWS. Topsoil and plant materials from the native habitats to be affected on-site would be applied to the watersheds of the restored/enhanced pools to the maximum extent practicable. Exotic weed control would be implemented within the restoration areas to protect and enhance habitat remaining on-site.

1. Plant palettes (species, size, and number/acre) and seed mix (species and pounds/acre) would be included in the restoration plans. The plant palette would include native species specifically associated with the onsite habitat type(s). If native plant species (no cultivars) cannot be obtained on site, an alternate site would be used only upon approval by USFWS. The source and proof of local origin of all plant material and seed would be provided to USFWS.

1. If inoculum would be used for restoration, the plan would identify any proposed donor pools and include documentation that they are free of versatile fairy shrimp (Branchinecta lindahli). No more than 5 percent of the basin area of any donor pool would be used for collection of inoculum. Inoculum would be collected from donor vernal pools when dry to avoid damaging or destroying fairy shrimp cysts and plant seeds. Whenever possible during collection of soil inoculum, a trowel would be used to pry up intact chunks of soil rather than loosening the soil by raking and shoveling which can damage the cysts and seeds. Soil inoculum would be kept separately for each donor pool, would be stored individually in labeled boxes that are adequately ventilated and kept out of direct sunlight to prevent the occurrence of fungus or excessive heating of the soil, and stored off site at an appropriate facility for vernal pool inoculum. No more than 5 percent of the basin area of any donor pool would be used for collection of inoculum. Soil inoculum would be spread out and raked into the bottoms of the restored/enhanced vernal pools.

1. Inoculum and planting would not be installed until USFWS approves the habitat restoration site grading. All planting would be installed in a way that mimics natural plant distribution and not in rows. Inoculum would not be introduced into the restored/enhanced vernal pools until after they have been demonstrated to retain water for the appropriate amount of time to support San Diego fairy shrimp [i.e., at least 30 days] and have been surveyed for versatile fairy shrimp to the satisfaction of USFWS. If versatile fairy shrimp are detected in the pools, inoculum would not be introduced until measures approved by USFWS are implemented to attempt to remove the versatile fairy shrimp from the pools. Inoculum would be placed in a manner that preserves, to the maximum extent possible, the orientation of the fairy shrimp cysts within the surface layer of soil (e.g., collected inoculum would be shallowly distributed within the pond so that cysts have the potential to be brought into solution upon inundation).

1. A map depicting the location of the control pools and a table detailing basin size, depth, ponding duration, native cover, nonnative cover, and presence of listed species for each pool.

1. If natural rain is inadequate to support plant establishment, artificial watering of the restored/enhanced vernal pools and their watersheds may be carried out as described in the restoration plan and agreed upon by USFWS. Any artificial watering would be conducted in a manner that prevents ponding in the pools. Artificial watering would not be used to germinate vernal pool plants, rather it would be used only as necessary to maintain any plants that germinated naturally but are at risk of dying before flowering and seed set. Any water to be used would be identified and documented to be free of contaminants that could affect the water quality of the pools and harm San Diego and Riverside fairy shrimp.

1. Any planting stock to be brought onto the restoration sites would be inspected by a pest inspector to ensure it is free of pest species that could invade natural areas, including but not limited to, Argentine ants (Linepithema humile), fire ants (Solenopsis invicta), and other insect pests.

1. All weeding personnel would be educated to distinguish between native and nonnative species so that local native plants are not inadvertently killed. All weeding within and immediately adjacent to the restored pools would be performed by hand. Use of weed trimmers and herbicides within and immediately adjacent to restored pools would only be used under conditions approved by USFWS. All herbicide and pesticide use would be under the direction of a licensed pest control advisor and would be applied by a licensed applicator, under the supervision of a vernal pool restoration specialist. Glyphosate-based herbicides, such as RoundUp or Aquamaster, would be applied on all areas that have been dethatched. Herbicide would only be applied when wind speed is less than 5 miles per hour, and spray nozzles would be of a design to maximize the size of droplets, to reduce the potential for drift of herbicide to non-target plants. A 10-foot buffer would be maintained around concentrations of any sensitive plant species. Application of herbicide would not occur if rain is projected within 24 hours of the scheduled application. When vernal pools are ponding or close to saturation, only hand herbicide application (i.e., saturated glove technique) would be used in and around the edges of pools by specially trained herbicide applicators under the direct supervision of the vernal pool restoration specialist. When vernal pools are not ponding or close to saturation, herbicide may be sprayed but applicators must stay at least 3 feet from the edge of the pools.
2. Five years of monitoring and success criteria for vernal pool and upland habitat restoration areas that includes quantitative hydrological, vegetation transects, viable cyst, hatched fairy shrimp, and gravid female measurements, and complete flora and fauna inventories, and photographic documentation. To minimize impacts to the vernal pool’s soil surface during monitoring, cobbles should be oriented within the restored vernal pools to serve as stepping stones.

1. Verification that the restoration of the vernal pools is complete would require written sign-off by USFWS. If a performance criterion is not met for any of the restored/enhanced vernal pools or upland habitat in any year, or if the final success criteria are not met, CBP should prepare an analysis of the cause(s) of failure and, if deemed necessary by USFWS, propose remedial actions for approval. If any of the restored/enhanced vernal pools or upland habitat have not met a performance criterion during the initial 5-year period, CBP’s maintenance and monitoring obligations would continue until USFWS deems the restoration successful, or contingency measures must be implemented. Restoration would not be deemed successful until at least 2 years after any significant contingency measures are implemented, as determined by USFWS.

1. Annual reports should be submitted to USFWS by December 1 of each year that assess both the attainment of yearly success criteria and progress toward the final success criteria. The reports should also summarize the project’s compliance with all mitigation measures. The first annual report should include as built grading, planting, and watering plans for the vernal pool restoration.

1. Restoration grading activities would be timed to avoid wet weather to minimize potential impacts (e.g., siltation) to extant vernal pools unless the area to be graded is at an elevation below extant pools. To achieve this goal, grading would comply with the following:

1. Grading would occur only when the soil is dry to the touch at the surface and 1 inch below. A visual check for color differences (i.e., darker soil indicating moisture) in the soil between the surface and 1 inch below indicates the soil is dry.

1. After a rain of greater than 0.2-inch, grading would occur only after the soil surface has dried sufficiently as described above, and no sooner than 2 days (48 hours) after the rain event ends.

1. Grading would commence only when no rain is forecast during the anticipated grading period.

1. To prevent erosion and siltation from storm water runoff due to unexpected rains, BMPs (e.g., silt fences, straw wattles) would be implemented as needed during grading.

1. If rain occurs during grading, work would stop and resume only after soils are dry, as described above.
2. Grading would be conducted in a manner to prevent run-off or erosion from entering extant vernal pools.

1. The changing of oil, refueling, and other actions that could result in a release of a hazardous substance should be restricted to designated areas that are a minimum of 100 feet from the Arnie’s Point vernal pool preserve and at a lower elevation if possible. Such designated areas should be surrounded with berms, sandbags, or other barriers to further prevent the accidental spill of fuel, oil, or chemicals. Any accidental spills should be immediately contained, cleaned up, and properly disposed of.

1. CBP would plan for 5 years of maintenance and monitoring for vernal pool restoration/enhancement (including a 20 percent contingency to be added to the total costs) to help guarantee the successful implementation.

1. CBP would implement long-term management, maintenance, and monitoring for the preservation of Arnie’s Point. CBP would submit a draft long-term management plan for the onsite conservation area to USFWS for review and approval with 60 days of initiating project impacts. The long-term management plan would include, but not be limited to, the following: (a) measures for controlling invasive species; (b) an estimated cost of long-term management of Arnie’s Point and funding mechanism; (c) to the extent CBP proposes to use contract personnel to implement the plan, the proposed land manager’s name, qualifications, business address, and contact information or if such information is unavailable a commitment to provide such information when it does become available; (d) proposed methods of protecting the resources in perpetuity (e.g., conservation easement or other measures); (e) a monitoring schedule; (f) measures to prevent human and invasive species encroachment; (g) contingency measures should problems occur; and (h) a commitment that CBP would not permit easements or activities (e.g., cattle grazing, fuel modification zones, public trails, drainage facilities, walls, maintenance access roads, utility easements) that negatively impact the value of the Arnie’s Point to listed species or result in soil disturbance and/or native vegetation removal within or on Arnie’s Point. If CBP determines that it is necessary to use Arnie’s Point in a manner that is inconsistent with the long-term management plan, then CBP would reinitiate consultation with USFWS.

Riverside fairy shrimp. Suitable habitat for Riverside fairy shrimp includes vernal pools, seasonally ponded areas within vernal swales, and ephemeral freshwater habitats. Riverside fairy shrimp are considered habitat specialists and differ from San Diego Fairy Shrimp in habitat use because they are found in moderate-to-deep pools (generally ranging from 10 inches to 10 ft in depth), longer-lived vernal pools, and ephemeral wetlands. Riverside fairy shrimp do not occur in riverine or marine waters or other permanent bodies of water. Restrictive soil layers are typically hardpan or claypan, and bedrock types are volcanic mud or lava flows. Other kinds of depressions that hold water of a similar volume, depth, and area, and for a similar duration and seasonality as vernal pools and ponded areas within swales could also provide potential habitat for Riverside fairy shrimp. Riverside fairy shrimp habitat is limited to non-vegetated ephemeral and vernal pool systems, which are generally large, and are found within chaparral and coastal sage scrub habitats from 100 to 1,300 ft in elevation. The most common unifying feature of Riverside fairy shrimp habitat, in general, is an ephemerally wet, flooded, or ponded area that is typically wet during a portion of the year and dry for the remainder of the year. A minimum period of inundation, or pool duration, that Riverside fairy shrimp need to hatch and reach sexual maturity is approximately 8 weeks.

Soils and soil series that underlie vernal pool habitat supporting Riverside fairy shrimp are generally characterized by a high content of coarse sandy grains (marine alluvial sediments), loams, or clay inclusions, or a combination of these, with a subsurface clay or hardpan layer. These are also limited in number and geographically fixed.

Riverside fairy shrimp was described as a species in 1990 (Eng et al. 1990) and was listed as federally endangered on August 3, 1993. Critical habitat for Riverside fairy shrimp was designated on May 30, 2001 (USFWS 2008) and revised on December 4, 2012 (77 FR 72069-72140). Riverside fairy shrimp is currently covered under the Vernal Pools of Southern California Recovery Plan, issued on September 3, 1998.

The project area falls within the known range of Riverside fairy shrimp, and while there are no vernal pools within the surrounding areas, there are ephemeral drainages nearby that could have ponding long enough for fairy shrimp from nearby pools to colonize and use. No critical habitat for the species is within the project area. During biological surveys, Riverside fairy shrimp were not observed near 1418 Firebreak Road. Protocol fairy shrimp surveys are complete for the 2020 winter/spring season.

3.6.3           Environmental Consequences

Effects on threatened and endangered species would be major and adverse if the species or habitats are adversely affected over relatively large areas, or if any of the following occur:

• Permanent loss of occupied, critical, or another suitable habitat,
• Temporary loss of critical habitat that adversely affects recolonization by threatened or endangered benthic resources, and

• Take (as defined under the ESA) of a threatened or endangered species.

3.6.3.1            Alternative 1: Partial Road Improvement

Quino checkerspot butterfly. Short- and long-term, moderate to major, direct and indirect, adverse effects from construction activities on the Quino checkerspot butterfly would be expected. It is possible that ground-disturbing activities associated with Alternative 1 could affect breeding practices. Surveys in 2019 also revealed the presence of Quino checkerspot butterfly host and food plants within the proposed disturbance area. Surveys found that an estimated 1.75 acres of Quino checkerspot butterfly habitat would be impacted with the implementation of Alternative 1. Overall, surveys revealed a high-quality potential habitat for the species due to its isolation, presence of host plants, and topographical features (openings, hilltops, roadbed). Although BMPs would likely minimize direct impacts on Quino checkerspot butterflies, indirect effects from the potential loss of host and food plants would occur.

If ground clearing or road maintenance occurs during the active period for Quino checkerspot butterflies (February– mid-May, depending on weather), there is a potential to impact adult Quino checkerspot butterflies. If adult Quino checkerspot butterflies forage within the proposed disturbance area during construction or maintenance activities, they could potentially be run over or hit by vehicles. Furthermore, impacts from construction and maintenance activities such as fugitive dust emissions and human activity could displace or kill Quino checkerspot butterflies.

Recently disturbed soils can increase the potential for invasive species, such as Lehman’s lovegrass and false-brome, to become established. These and other invasive species tend to form dense stands that out-compete larval host species and nectar-providing species resulting in degraded habitat. The Quino checkerspot butterfly occurs in open areas with low-growing and sparse vegetation that are typically formed or maintained by some form of disturbance. Most of the vegetation-control activities would be limited to the landscaped vegetation within the proposed 1418 Firebreak Road. Outside of the proposed disturbance area, vegetation control would be limited to the minimum extent necessary to create defensible space for wildfires.

While it is possible to avoid impacts to adult Quino checkerspot butterfly individuals with the implementation of mitigation measures and BMPs, the impact on host and food plants also found in the project area would be inevitable. In addition, the USFWS considers any area within 0.6 miles (estimated movement distance) of a known Quino checkerspot butterfly observation to be occupied habitat. Therefore, Alternative 1 could affect this habitat and is likely to adversely affect Quino checkerspot butterfly.

BMPs would be implemented to minimize these direct and indirect effects on Quino checkerspot butterfly adults, eggs, and larvae, in the unlikely event they occur within the proposed project area. Effects could include injury or crushing of individuals during site preparation and by use of construction equipment. Indirect effects could also occur from fugitive dust emissions, increased invasive species, and loss of habitat from site-preparation activities.

Coastal California gnatcatcher. Short- and long-term, direct and indirect, negligible, adverse effects on the coastal California gnatcatcher would be expected. Surveys conducted in 2019 found that an estimated 1.42 acres of coastal California gnatcatcher habitat would be impacted with the implementation of Alternative 1. Surveys also indicated one pair of coastal California gnatcatchers were present either near or within the project area throughout the duration of the survey period. One pair and three juveniles were observed outside of the protocol survey period when a biologist was conducting a rare plant survey within the same survey area. It is possible that activity associated with Alternative 1 could affect species breeding. BMPs would be implemented to avoid or minimize these direct and indirect effects to a level that is negligible.

Noise, fugitive dust, and human activity, which could result from improvement activities to 1418 Firebreak Road, could cause coastal California gnatcatchers to avoid areas in which they might otherwise forage or nest. Any temporary “loss” (due to avoidance by gnatcatchers) of forage and nesting habitat would be reduced or eliminated by implementing BMPs. Effects on coastal California gnatcatchers would be negligible.

Least Bell’s vireo. Short- and long-term, direct and indirect, negligible, adverse effects on the least Bell’s vireo would be expected. Based on the lack of the riparian habitat for least Bell’s vireo

nesting, it is unlikely that the species would occur within the project area and the species was not observed during the 2019 surveys. However, occupied habitat does exist nearby, within the Otay River Riparian corridor. At this distance, there would be the potential for short-term noise impacts at the proposed staging area. Noise impacts on wildlife are discussed further in Section 3.11. BMPs would be implemented to avoid or minimize these direct and indirect effects to a level that is negligible.

San Diego fairy shrimp. Short- and long-term, direct and indirect, moderate to major, adverse effects on San Diego fairy shrimp would be expected. San Diego fairy shrimp are obligate vernal pool inhabitants and require rainwater that collects in depressions to survive (USFWS 2008). While no vernal pools are present in the project area, there are road pools in the access road that could have been ponding long enough for fairy shrimp from nearby pools to colonize and use. During biological surveys, San Diego fairy shrimp were observed in ephemeral basins within low areas of 1418 Firebreak Road. Habitat destruction would be a direct impact on the species due to construction and maintenance activities. BMPs would be implemented to avoid and minimize these direct and indirect effects to a negligible level.

Riverside fairy shrimp. No direct or indirect impacts on Riverside fairy shrimp are expected. Riverside fairy shrimp, similar to San Diego fairy shrimp, are obligate vernal pool inhabitants and require rainwater that collects in depressions to survive (USFWS 2008). During biological surveys, Riverside fairy shrimp were not observed near 1418 Firebreak Road. Protocol fairy shrimp surveys are complete for the 2020 winter/spring season and presence of Riverside fairy shrimp has not been confirmed to date. Therefore, Alternative 1 is not likely to impact this species.

3.6.3.2            Alternative 2: Complete Road Improvement

Quino checkerspot butterfly. Short- and long-term, minor to major, direct and indirect, adverse effects from construction activities on the Quino checkerspot butterfly would be expected from implementing Alternative 2. As with Alternative 1, it is possible that activity associated with Alternative 2 could affect species breeding. Although BMPs would likely minimize direct impacts on Quino checkerspot butterflies, indirect effects from the potential loss of host and food plants would occur. Impacts due to the implementation of Alternative 2 would be expected to be greater than Alternative 1 because construction would take place over a longer period of time and within a larger geographical area. Surveys found that an estimated 4.32 acres of Quino checkerspot butterfly habitat would be impacted with the implementation of Alternative 2.

Coastal California gnatcatcher. Short-term, direct and indirect, negligible, adverse effects on the coastal California gnatcatcher would be expected with the implementation of Alternative 2. Surveys found that an estimated 0.50 acres of coastal California gnatcatcher habitat would be impacted with the implementation of Alternative 2. As with Alternative 1, it is possible that activity associated with Alternative 2 could affect species breeding. Impacts due to the implementation of Alternative 2 would be expected to be greater than Alternative 1 as construction would take place over a longer period of time and within a larger geographical area. As with Alternative 1, BMPs would be implemented to avoid and minimize these direct and indirect effects to a level that is negligible.

Least Bell’s vireo. Short-term, direct and indirect, negligible, adverse effects on the least Bell’s vireo would be expected with the implementation of Alternative 2. Similar to Alternative 1, there would be the potential for noise impacts on the species at the proposed staging area. Implementation of Alternative 2 would be expected to cause a greater impact on the species due to the extended construction period resulting in noise being produced over a longer duration. As with Alternative 1, BMPs would be implemented to avoid and minimize these direct and indirect effects to a negligible level.

San Diego fairy shrimp. Short-term, direct and indirect, minor to moderate, adverse effects on San Diego fairy shrimp would be expected with the implementation of Alternative 2. Habitat destruction caused by this alternative would be expected to be greater than Alternative 1 due to the larger disturbance area, resulting in a higher potential of habitat being encountered. As with Alternative 1, BMPs would be implemented to avoid and minimize these direct and indirect effects to a negligible level.

Riverside fairy shrimp. Similar to Alternative 1, no direct or indirect impacts on Riverside fairy shrimp are expected with the implementation of Alternative 2.

3.6.3.3            Alternative 3: Preferred Alternative (Improve Drainage Features Without Widening Road)

Quino checkerspot butterfly. Short-term, direct and indirect, minor to moderate, adverse effects on the Quino checkerspot butterfly would be expected to occur with the implementation of Alternative 3. As with Alternative 1, it is possible that activity associated with Alternative 3 could affect species breeding. Impacts due to the implementation of Alternative 3 would be expected to be similar to or slightly less than Alternative 1 due to road widening. Surveys found that an estimated 1.11 acres of Quino checkerspot butterfly habitat would be impacted with the implementation of Alternative 3.

Coastal California gnatcatcher. Short-term, direct and indirect, negligible, adverse effects on the coastal California gnatcatcher would be expected with the implementation of Alternative 3. Surveys found that an estimated 0.50 acres of coastal California gnatcatcher habitat would be impacted with the implementation of Alternative 3. As with Alternative 1, it is possible that activity associated with Alternative 3 could affect species breeding. Impacts due to the implementation of Alternative 3 would be expected to be similar to or slightly less than Alternative 1 due to the smaller disturbance area.

Least Bell’s vireo. Short-term, direct and indirect, negligible, adverse effects on the least Bell’s vireo would be expected with the implementation of Alternative 3. Similar to Alternative 1, there would be the potential for noise impacts on the species. Impacts due to the implementation of Alternative 3 would be expected to be similar to or slightly less than Alternative 1 due to the smaller disturbance area.

San Diego fairy shrimp. Short-term, direct and indirect, minor to moderate, adverse effects on San Diego fairy shrimp would be expected with the implementation of Alternative 3. Habitat destruction caused by this alternative would be expected to be similar to or slightly less than Alternative 1 due to the smaller disturbance area.

Riverside fairy shrimp. Similar to Alternative 1, no direct or indirect impacts on Riverside fairy shrimp are expected with the implementation of Alternative 3.

3.6.3.4            Alternative 4: No Action Alternative

Under the No Action Alternative, CBP would not be maintaining, repairing, and improving the road. CBP would continue to use the existing two-track 1418 Firebreak Road, which could impact San Diego fairy shrimp currently residing in road pools as well as Quino checkerspot butterfly using the road. If the current road further deteriorates, newly created routes in currently undisturbed habitat could be driven by vehicles causing further impacts to the fairy shrimp. No impacts on coastal California gnatcatcher or least Bell’s vireo, would be expected.

3.7        HYDROLOGY AND GROUNDWATER

3.7.1           Definition of the Resource

Evaluation of hydrology requires a study of the occurrence, distribution, and movement of water, and its relationship with the environment. Many factors affect the hydrology of a region, including natural precipitation and evaporation rates and outside influences such as groundwater withdrawals. Groundwater is a subsurface hydrologic resource, and it recharges surface water. It is used for drinking, irrigation, and industrial processes. Groundwater typically can be described in terms of its depth from the surface, aquifer or well capacity, water quality, recharge rate, and surrounding geologic formations. In California, groundwater use is managed by the CDWR.

3.7.2           Affected Environment

Climate and Hydrology. The project area occurs within the Mediterranean Division – California Coastal Sage, Chaparral, and Oak Woodland Province (Bailey 1995). Regional climate is defined by hot, dry summers and rainy, mild winters with annual temperatures ranging from 55°F to 71°F. Average low temperatures range from 45°F in December to 66°F in August. Average high temperatures range from 67°F in December to 78°F in August. The record low and record high temperatures for the region are 22°F and 96°F, respectively (NOAA 2019; U.S. Climate Data 2019). Average precipitation totals 9.81 inches per year. The elevation of the project area ranges from 525 ft above mean sea level (AMSL) at the northern terminus of 1418 Firebreak Road to 1,435 ft AMSL at the southern terminus. (Google Earth 2019).

Much of the region is dominated by the chaparral climax association, which forms a mosaic across the region. A wide variety of wildlife use this province, especially birds, for whom coastal California constitutes a major migration route. Threatened and endangered species also use habitat near the project area and are subject to regional protection plans.

Groundwater. The aquifers in Southern California are classified by the USGS as either coastal basin aquifers or basin and range aquifers (USGS 1995). Coastal basin aquifers are partly filled with marine sedimentary rocks that were deposited during periodic encroachment of the sea, and with terrestrial deposits consisting of weathered igneous and sedimentary rock material, which was transported into the basins via mountain streams. Most of the fresh water is contained in aquifers consisting of sand and gravel terrestrial deposits and confining units of fine-grained material like

silt and clay. Water enters coastal basin aquifers primarily when runoff from precipitation in the surrounding mountains infiltrates the permeable sediments of the valley floor. Some direct recharge is provided by precipitation falling on the valley floor, but most of the precipitation evaporates or is transpired by plants. Water can also enter the aquifer system as lateral subsurface flow from an adjacent basin; however, basin and range aquifers are not continuous because of the complex faulting in the region.

There are four aquifer types collectively known as basin and range aquifers, volcanic-rock aquifers, carbonate-rock aquifers, and basin-fill aquifers. Any combination of the four aquifers could be in, or below, any basin and constitute four separate sources of water; or they might be hydraulically connected and form a single source. The aquifers are formed from volcanic and carbonate rocks and unconsolidated to consolidated basin-fill deposits. The basin-fill deposits are the most productive aquifers and are generally found in internally drained individual alluvial basins, which are separated by low mountains (USGS 1995). Most of these basins are small, generally averaging less than 10 square miles in area.

The U.S./Mexico international border in California is composed of the South Coast and Colorado River hydrologic regions. Within the San Diego area of the South Coast hydrologic region, there are 27 groundwater basins covering 277,000 acres. Groundwater is found in unconfined alluvial aquifers in most of the basins and has local impairments of nitrate, sulfate, and total dissolved solids (CDWR 2003). The Colorado River hydrologic region covers approximately 13 million acres in southeastern California, with 64 groundwater basins or subbasins. Within the Colorado River hydrologic region lies the Imperial Valley Groundwater Basin. This basin is approximately 1,870 square miles in southeastern California along the U.S./Mexico international border and is the primary aquifer in the project area. It is bounded to the north by the Salton Sea, which is also its discharge point. The Imperial Valley Groundwater Basin is composed of an upper and lower aquifer, which are separated by a semi-permeable aquitard. Recharge comes from irrigation return, rainfall and surface runoff percolation, and seepage from unlined canals, such as the Coachella and All-American canals. Water quality varies in the basin, but it is generally unusable for domestic or irrigation purposes unless it is treated first, since it has high levels of dissolved solids, fluoride, and boron. Many of the water quality issues can be attributed to recharge provided by the highly polluted New River, which drains the Mexicali Valley (CDWR 2003).

3.7.3           Environmental Consequences

The Proposed Action would be considered to cause a major adverse impact on hydrology or groundwater if it were to substantially affect water quality; substantially reduce water availability or supply to existing users; threaten or damage hydrologic characteristics; or violate established federal, state, or local laws and regulations.

3.7.3.1            Alternative 1: Partial Road Improvement

Climate and hydrology. No impacts on climate and hydrology with respect to the ecoregions or precipitation regime would be anticipated with the implementation of Alternative 1. Climate and hydrologic cycles are large-scale processes that affect local areas; however, a significant contribution of greenhouse gas (GHG) emissions or alteration to the existing topography,

vegetation, or precipitation regime would be required to modify climate or hydrology. Those large- scale changes would not occur with this project.

Groundwater. Short-term, negligible, indirect, adverse impacts could occur on groundwater from vegetation clearing and debris removal, which could cause the deposition of fill materials or increased erosion into groundwater recharge areas. Long-term, negligible to minor, indirect, beneficial impacts on groundwater could occur from a decrease in erosion because roadways would be properly maintained with the installation of water bars, which would reduce the effects incurred from negligence, such as washout and long-term sedimentation.

Maintenance and repair of the road could lead to short-term, minor, adverse, impacts on groundwater because grading and other ground-disturbing activities would result in erosion and sedimentation. In addition, maintenance and repair activities could require the clearing of vegetation and rock, which could alter the flow of water and percolation of precipitation into the ground, resulting in a long-term, negligible, adverse impact on groundwater recharge.

Rutting can occur along graded earth and sand roads, which is exacerbated by rain events that further erode the surface. Unmanaged stormwater flow also causes general erosion to occur, washing out complete sections of road and in many instances making roads impassable. Maintenance and repair of the existing road would have short- and long-term, minor to moderate, beneficial impacts on groundwater by minimizing erosion of potentially contaminated (e.g., oils, metals) road material into groundwater recharge areas. Improper maintenance could result in short- term, negligible to minor, direct and indirect, adverse impacts on groundwater by increasing erosion or introducing fill material into groundwater recharge areas.

All necessary erosion-control BMPs (see Appendix D) would be adopted to ensure stabilization of the project area. All of the standards CBP is adopting are developed based on comprehensive engineering analysis, proven BMPs adopted by other federal agencies, and mitigation measures derived from extensive consultation with both regulatory and resource agencies.

3.7.3.2            Alternative 2: Complete Road Improvement

Climate and hydrology. As with Alternative 1, no impacts on climate and hydrology with respect to the ecoregions or precipitation regime would be anticipated.

Groundwater. Short-term, negligible, indirect, adverse impacts could occur on groundwater from vegetation clearing and debris removal as with Alternative 1. Long-term, negligible to minor, indirect, beneficial impacts on groundwater could occur from a decrease in erosion because roadways would be properly maintained. Impacts associated with Alternative 2, both beneficial and adverse, would be expected to be greater than those impacts associated with Alternative 1 due to the greater disturbance and change associated with a complete road improvement. Under Alternative 1, 4,885 linear feet of roadway would be impacted while 12,983 linear feet of roadway would be impacted with the implementation of Alternative 2.

As with Alternative 1, maintenance and repair of the roadway could lead to short-term, minor, adverse, impacts on groundwater because grading and other ground-disturbing activities would result in erosion and sedimentation. Although, long-term, minor beneficial impacts on groundwater would occur through properly maintained roads. These impacts associated with

Alternative 2 would be expected to be greater than those impacts associated with Alternative 1 due to the greater disturbance and change associated with a complete road improvement. Maintenance and repair of the existing roadway would be in accordance with proven maintenance and repair standards. All necessary erosion-control BMPs would be adopted to ensure stabilization of the project areas.

3.7.3.3            Alternative 3: Preferred Alternative (Improve Drainage Features Without Widening Road)

Climate and hydrology. As with Alternative 1, no impacts on climate and hydrology with respect to the ecoregions or precipitation regime would be anticipated.

Groundwater. Short-term, negligible, indirect, adverse impacts could occur on groundwater from vegetation clearing and debris removal. Impacts associated with Alternative 3 would be expected to be similar to those impacts associated with Alternative 1.

As with Alternative 1, maintenance and repair of the roadway could lead to short-term, minor, adverse, impacts on groundwater because ground-disturbing activities would result in erosion and sedimentation. Impacts associated with Alternative 3 would be expected to be similar to those impacts associated with Alternative 1.

3.7.3.4            Alternative 4: No Action Alternative

Under the No Action Alternative, short- and long-term, minor, direct and indirect, adverse impacts on hydrology and groundwater would be anticipated as maintenance and repair activities would not be implemented. Therefore, the degrading roadway could increase flood risk. Changes in hydrology from clogged drainage structures could occur, which could reduce the potential for groundwater recharge in the area. Impacts on hydrology and groundwater under the No Action Alternative would be anticipated to be greater than impacts for Alternative 1 because unlike Alternative 1, mitigation measures for stormwater drainage would not be implemented under the No Action Alternative.

3.8        SURFACE WATERS AND WATERS OF THE UNITED STATES

3.8.1           Definition of the Resource

Surface water resources generally consist of wetlands, lakes, rivers, and streams. All of these surface water components contribute to the economic, ecological, recreational, and human health of a community.

Waters of the United States are defined within the CWA, and jurisdiction is addressed by the U.S. Environmental Protection Agency (USEPA) and the USACE. These agencies assert jurisdiction over traditional navigable waters and their relatively permanent tributaries, and the wetlands that are adjacent to these waters (USEPA 2010a). The California State Water Resources Control Board, through the appropriate RWQCB, regulates activities pursuant to Section 401 and Section 402 of the CWA (USEPA 2016) within California.

The CWA establishes the basic structure for regulating discharges of pollutants into the Waters of the United States (USEPA 2010b), with the objective of restoration and maintenance of chemical,

physical, and biological integrity of the Nation’s waters (USEPA 2010a). To achieve this objective, several goals were enacted, including (1) eliminate discharge of pollutants into navigable waters by 1985; (2) achieve water quality that provides for the protection and propagation of fish, shellfish, and wildlife and provides for recreation in and on the water by 1983;

(3) prohibit the discharge of toxic pollutants in toxic amounts; (4) provide federal financial assistance to construct publicly owned waste treatment works; (5) develop and implement the national policy that area-wide waste treatment management planning processes ensure adequate control of sources of pollutants in each state; (6) enforce the national policy that a major research and demonstration effort be made to develop technology necessary to eliminate the discharge of pollutants into navigable waters, waters of the contiguous zone, and the oceans; and (7) establish the national policy that programs be developed and implemented in an expeditious manner to enable the goals to be met through the control of both point and nonpoint sources of pollution.

The USACE regulates the discharge of dredged and fill material (e.g., concrete, soil, cement block, gravel, sand) into Waters of the United States including adjacent wetlands under Section 404 of the CWA (USEPA 2010b) and work on structures in or affecting navigable Waters of the United States under Section 10 of the Rivers and Harbors Act of 1899 (USEPA 2010c).

Wetlands and riparian habitats are ecologically important communities that provide many benefits for people, fish, and other wildlife. They provide key habitat for a wide array of plant and animal species, including resident and migrating birds, amphibian and fish species, mammals, and insects. Vegetation production and diversity are usually very high in and around these sites, with many plant species adapted only to these unique environments. In addition, wetlands and riparian zones provide a variety of hydrologic functions vital to ecosystem integrity. They protect and improve water quality by storing floodwaters, recharging groundwater, and filtering out nutrients and chemicals (USEPA 2001a). Development and conversion of wetlands and riparian zones affects wildlife diversity, carrying capacity, and hydrologic regime. More than 220 million acres of wetlands are estimated to have existed in the lower 48 states in the 1600s. More than half of those wetland acres have been drained or converted to other uses, with the most impacts occurring in the 1950s to 1970s. Approximately 60,000 acres of wetlands are still lost annually, primarily from conversion for agriculture and other development purposes (USEPA 2001b).

Wetlands are a protected resource under E.O. 11990, Protection of Wetlands, issued in 1977 “to avoid to the extent possible the short- and long-term, adverse impacts associated with the destruction or modification of wetlands and to avoid direct or indirect support of new construction in wetlands wherever there is a practicable alternative.” Wetlands have been defined by agencies responsible for their management. The term “wetland,” used herein, is defined using USACE conventions. The USACE has jurisdiction to protect wetlands under Section 404 of the CWA that are defined as “. . . areas that are inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions” (33 CFR 328.3[b]).

Three diagnostic characteristics must be met to classify an area as a wetland: (1) more than 50 percent of the dominant vegetation species present must be classified as obligate (species that are found greater than 99 percent of the time in wetlands), facultative wetland (species that are found 67 to 99 percent of the time in wetlands), or facultative (species that are found 34 to 66 percent of the time in wetlands); (2) the soils must be classified as hydric; and (3) the area is either permanently or seasonally inundated, or saturated to the surface at some time during the growing season of the prevalent vegetation (USACE 1987).

Wetlands are protected as a subset of “the Waters of the United States” under Section 404 of the CWA. The term “Waters of the United States” has a broad meaning under the CWA and incorporates deep water aquatic habitats and special aquatic habitats, including wetlands. Section 404 of the CWA authorizes the USACE to issue permits for the discharge of dredged or fill materials into the Waters of the United States, including wetlands. In addition, Section 404 of the CWA also grants states with sufficient resources the right to assume these responsibilities. Section 401 of the CWA gives the state board and regional boards the authority to regulate through water quality certification any proposed federally permitted activity that could result in a discharge to water bodies, including wetlands. The state may issue certification, with or without conditions, or deny certification for activities that might result in a discharge to water bodies (USEPA 2010b).

Only 0.077 acres of potential CWA Section 404 jurisdictional area were found within the survey area. These acres were classified as ephemeral drainage.

3.8.2           Affected Environment

Thirteen non-jurisdictional surface water features were identified during wetland delineations (see Figure 3-2). Two features were ephemeral drainages, episodic channels that appear to convey flows only during and immediately after precipitation events, and eleven features were road pools or ponding in the existing road due to low permeability of the soils. These features have not been delineated as jurisdictional based on the 2008 USACE and USEPA joint memorandum on guidance (post-U.S. Supreme Court decision in Rapanos and Carabell vs. The United States). This guidance states that agencies will not assert jurisdiction over erosional features and ditches that are only draining upland. Executive guidance established during the Obama administration was rescinded and the jurisdiction reverts to the post-Rapanos delineation approach, therefore this guidance is again relevant to the jurisdictional assessments.

Non-Wetland Waters. The project area contains two ephemeral drainages. The western crossing has a clearly delineated bed and bank with an ordinary high-water mark (OHWM). The eastern drainage is more complex, but due to the high levels of disturbance, there is not a clear bed and bank, but there is evidence of an OHWM in portions of the eastern drainage. There are no wetlands or Waters of the United States in the project area. However, similar to wetland waters, these features occur in areas that have been heavily altered by human activity.

Other Features Not Mapped as Potentially Jurisdictional. There are many eroded channels within the existing footprint of 1418 Firebreak Road, especially towards the northern end of the project area. The road is impassable in some areas and bypass roads have been informally constructed. Additionally, there are eleven ponded areas referred to as road pools that are not associated with any drainages or other potential features. Although these features would be considered isolated waters and not regulated by USACE, they are potential habitat for endangered species and may be regulated by ESA.

Figure 3-2. Water Features within the Proposed Project Area

3.8.3           Environmental Consequences

3.8.3.1            Alternative 1: Partial Road Improvement

Short-term, negligible, indirect, adverse impacts could occur from vegetation clearing and debris removal, which could cause the deposition of fill materials or increased sedimentation into surface water or ephemeral drainages. However, maintenance and repair of the roadway would be conducted in such a manner as to have negligible impacts on surface waters and drainage resources to the maximum extent practical. Erosion-control BMPs would be adopted to maintain runoff on site and would minimize the potential for adverse effects on downstream water quality. Pertinent local, state, and federal permits would be obtained for any work, including work that could occur near surface water or ephemeral drainages.

Installation of water bars would result in short-term, minor, adverse impacts on water quality due to an increase in turbidity from a disturbance in sediments and potential for contaminants to enter water bodies during construction activities, such as through leaking or spills from construction equipment. Long-term, beneficial impacts would occur after installation because the drainage features would properly manage stormwater flow and minimize long-term erosion.

3.8.3.2            Alternative 2: Complete Road Improvement

Implementation of Alternative 2 would result in short-term, negligible, indirect, adverse impacts from vegetation clearing and debris removal. Impacts resulting from Alternative 2 would be expected to be great than those of Alternative 1 as the two ephemeral drainages fall within the project area for Alternative 2. Loss of waters resulting from the implementation of Alternative 2 would be minor to moderate. As with Alternative 1, erosion-control BMPs would be adopted to maintain runoff on site and minimize the potential for adverse effects on downstream water quality. Pertinent local, state, and federal permits would be obtained for any work in waterways.

As with Alternative 1, installation of water bars would result in short-term, minor, adverse impacts on water quality due to an increase in turbidity from a disturbance in sediments and potential for contaminants to enter into water bodies during construction activities. Long-term, beneficial impacts would occur after installation activities have ceased and stormwater flow is properly managed.

3.8.3.3            Alternative 3: Preferred Alternative (Improve Drainage Features Without Widening Road)

Implementation of Alternative 3 would result in short-term, negligible, indirect, adverse impacts from vegetation clearing and debris removal. Impacts resulting from Alternative 3 would be expected to be similar to Alternative 1. With the installation water bars, long-term, minor beneficial impacts on water quality would occur due to drainage features properly managing stormwater flow and minimizing long-term erosion.

3.8.3.4            Alternative 4: No Action Alternative

Under the No Action Alternative, there is a potential for short- and long-term, minor, direct and indirect adverse impacts on surface waters. The No Action Alternative would result in greater impacts on surface waters than Alternative 1 because the remaining area would be considered a minimal flood hazard area. Therefore, the degrading roadway could lead to increased sediments, nutrients, and contaminants in water-related features and blocked drainage structures could increase flood risk.

3.9        FLOODPLAINS

3.9.1           Definition of the Resource

Floodplains are areas of low-level ground present along rivers, stream channels, or coastal waters that are periodically inundated. Floodplain ecosystem functions include natural moderation of floods through flood storage and conveyance, groundwater recharge, nutrient cycling, water quality maintenance, and support of a diversity of plants and animals. Floodplains provide a broad area to spread out and temporarily store floodwaters. This reduces flood peaks and velocities and the potential for erosion. In their natural vegetated state, floodplains slow the rate at which the incoming overland flow reaches the main water body (FEMA 1994).

Floodplains are subject to periodic or infrequent inundation due to rain or melting snow. Risk of flooding typically hinges on local topography, the frequency of precipitation events, and the size of the watershed above the floodplain. Flood potential is evaluated by Federal Emergency Management Agency (FEMA), which defines the 100-year floodplain. The 100-year floodplain is the area that has a 1 percent chance of inundation by a flood event in a given year (FEMA 1994). Certain facilities inherently pose too great a risk to be in either the 100- or 500-year floodplain, such as hospitals, schools, or storage buildings for irreplaceable records. Federal, state, and local regulations often limit floodplain development to passive uses, such as recreational and preservation activities, to reduce the risks to human health and safety. E.O. 11988, Floodplain Management, requires federal agencies to determine whether a proposed action would occur within a floodplain. This determination typically involves consultation of appropriate FEMA Flood Insurance Rate Maps (FIRMs), which contain enough general information to determine the relationship of the project area to nearby floodplains. E.O. 11988 directs federal agencies to avoid floodplains unless the agency determines that there is no practicable alternative. Where the only practicable alternative is to site in a floodplain, a specific step-by-step process must be followed to comply with E.O. 11988 outlined in the FEMA document, Further Advice on Executive Order 11988 Floodplain Management.

3.9.2           Affected Environment

The project area is mapped as an area of minimal flood hazard. No existing floodplain information on the project area exists; however, the northern access to Firebreak Road is within 300 feet of Jamul Creek. The staging area and the access road to Firebreak Road are in low areas near the river. Based on vegetation and topography, it is likely these areas are within the historic floodplain for the Otay River. The surrounding area is a minimal flood hazard; however, no floodplain mapping for the Otay River exists for the project area.

The remainder of the project area goes upslope and most of the project area is either climbing to or along a ridgeline and outside of any floodplains. All water from this project area drains into the Otay River Watershed, specifically the Dulzura segment, which drains into San Diego Bay.

3.9.3           Environmental Consequences

The Proposed Action would be considered to cause a major, adverse impact on floodplains if it were to site habitable structures within the floodplain or alter flood hazards as designated on a FIRM.

3.9.3.1            Alternative 1: Partial Road Improvement

Short-term, negligible, indirect impacts on floodplain areas would be anticipated from the implementation of Alternative 1. Due to vegetation clearing, increased sedimentation into drainage structures could occur. However, clearing blocked drainage structures of debris and fill materials would result in short- and long-term, direct and indirect, beneficial impacts on floodplains by improving conveyance of floodwaters. Widening of the road and clearing of vegetation would result in an increase of flow as well as an increase in the speed of flow. However, water cutouts would act to mitigate these effects. BMPs would be implemented to minimize any potential impacts on floodplains. The maintenance and repair of the existing roadway would be conducted in such a manner as to have negligible impacts on floodplains as drainage mitigation measures would be implemented.

3.9.3.2            Alternative 2: Complete Road Improvement

Short-term, negligible, indirect impacts on floodplain areas would be anticipated from the implementation of Alternative 2. As with Alternative 1, vegetation clearing could cause increased sedimentation into drainage structures, though clearing blocked drainage structures of debris and fill materials would result in short- and long-term, direct and indirect, beneficial impacts on floodplains. BMPs would be implemented to minimize any potential impacts on floodplains. Impacts associated with this alternative would be comparable to those of Alternative 1.

3.9.3.3            Alternative 3: Preferred Alternative (Improve Drainage Features Without Widening Road)

Alternative 3 would have short- and long-term, minor, direct, beneficial impacts on floodplains by minimizing erosion of road material into floodplain areas. Improper maintenance of the road would result in short- to long-term, negligible to minor, direct and indirect, adverse impacts on floodplains by increasing erosion and adding fill materials into floodplain areas. Impacts associated with Alternative 3 would be expected to be similar to those of Alternative 1.

3.9.3.4            Alternative 4: No Action Alternative

Under the No Action Alternative, there is a potential for short- and long-term, minor, direct and indirect, adverse impacts on floodplains as maintenance and repairs activities would not be conducted. Degrading roadway and blocked drainage structures impair flow, which could increase flood risk. This approach would result in greater impacts on floodplains than Alternative 1 because maintenance and repair activities would not be conducted.

3.10    AIR QUALITY

3.10.1      Definition of the Resource

Air quality is defined by the concentration of various pollutants in the atmosphere at a given location. The air quality in a region is a result of not only the types and quantities of atmospheric pollutants and pollutant sources in an area, but also surface topography, the size of the topological “air basin,” and the prevailing meteorological conditions.

Under the CAA, the USEPA developed numerical concentration-based standards, or National Ambient Air Quality Standards (NAAQS), for pollutants that have been determined to affect human health and the environment. The NAAQS represent the maximum allowable concentrations for ozone (O3), measured as either volatile organic compounds (VOCs) or total nitrogen oxides (NOx), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur oxides (SOx), respirable particulate matter (including particulate matter equal to or less than 10 microns in diameter [PM10] and particulate matter equal to or less than 2.5 microns in diameter [PM2.5]), and lead (Pb) (40 CFR Part 50). The CAA also gives the authority to states to establish air quality rules and regulations.

California has also established its own ambient air quality standards for these pollutants, which in some cases are stricter than the NAAQS, and also include sulfates, hydrogen sulfide, and visibility reducing particulates as principal air pollutants.

The USEPA classifies the air quality in an air quality control region (AQCR), or in subareas of an AQCR, according to whether the concentrations of criteria pollutants in ambient air exceed the NAAQS. Areas within each AQCR are therefore designated as either “attainment,” “nonattainment,” “maintenance,” or “unclassified” for each of the six criteria pollutants. Attainment means that the air quality within an AQCR is better than the NAAQS; nonattainment indicates that criteria pollutant levels exceed NAAQS; maintenance indicates that an area was previously designated nonattainment but is now attainment; and an unclassified air quality designation by USEPA means that there is not enough information to appropriately classify an AQCR, so the area is considered attainment. In accordance with the CAA, each state must develop a State Implementation Plan (SIP), which is a compilation of regulations, strategies, schedules, and enforcement actions designed to move the state into compliance with all NAAQS.

The General Conformity Rule requires that any federal action meet the requirements of a SIP or Federal Implementation Plan. More specifically, CAA conformity is ensured when a federal action does not cause a new violation of the NAAQS; contribute to an increase in the frequency or severity of violations of NAAQS; or delay the timely attainment of any NAAQS, interim progress milestones, or other milestones towards achieving compliance with the NAAQS. The General Conformity Rule applies only to regionally significant actions in nonattainment or maintenance areas.

Federal Prevention of Significant Deterioration (PSD) regulations apply in attainment areas to a major stationary source, (i.e., source with the potential to emit of 250 tons per year [tpy] of any criteria pollutant), and a significant modification to a major stationary source, (i.e., change that adds 15 to 40 tpy to the facility’s potential to emit depending on the pollutant). PSD regulations can also apply to stationary sources if (1) a proposed project is within 6.21 miles of national parks

or wilderness areas, (i.e., Class I Areas), and (2) regulated stationary source pollutant emissions would cause an increase in the 24-hour average concentration of any regulated pollutant in the Class I area of 1 microgram per cubic meter (μg/m³) or more (40 CFR 52.21[b][23][iii]). A Class I area includes national parks larger than 6,000 acres, national wilderness areas and national memorial parks larger than 5,000 acres, and international parks. PSD regulations also define ambient air increments, limiting the allowable increases to any area’s baseline air contaminant concentrations, based on the area’s class designation (40 CFR 52.21[c]).

Title V of the CAA Amendments of 1990 requires states and local agencies to use a permitting process for major stationary sources. A major stationary source has the potential to emit more than 100 tpy of any one criteria air pollutant, 10 tpy of a hazardous air pollutant (HAP), or 25 tpy of any combination of HAPs. The purpose of the permitting rule is to establish regulatory control over large, industrial-type activities and monitor their impact on air quality. Section 112 of the CAA defines the sources and kinds of HAPs.

GHGs are gaseous emissions that trap heat in the atmosphere. These emissions occur from natural processes and human activities. The most common GHGs emitted from natural processes and human activities include carbon dioxide (CO2), methane, and nitrous oxide. GHGs are mainly produced by the burning of fossil fuels and through industrial and biological processes. On September 22, 2009, the USEPA issued a final rule for mandatory GHG reporting from large GHG emissions sources in the United States. The purpose of the rule is to collect comprehensive and accurate data on CO2 and other GHG emissions that can be used to inform future policy decisions. In general, the threshold for reporting is 25,000 metric tons or more of CO2 equivalent emissions per year but excludes mobile source emissions. GHG emissions will also be factors in PSD and Title V permitting and reporting, according to a USEPA rulemaking issued on June 3, 2010 (75 FR 31514). GHG emissions thresholds of significance for stationary sources are 75,000 tons CO2 equivalent per year and 100,000 tons CO2 equivalent per year under these permit programs.

3.10.2      Affected Environment

The project area is within the San Diego Intrastate AQCR (SDIAQCR) (40 CFR 81.164). San Diego County is designated by USEPA as nonattainment for 8-hour O3 (moderate), maintenance for CO, and attainment for the remaining criteria pollutants (USEPA 2019). The county is designated by the California Environmental Protection Agency (Cal/EPA) as nonattainment for 8- and 1-hour O3, PM10, and PM2.5 and attainment for the remaining criteria pollutants and sulfates, hydrogen sulfide, and visibility reducing particulates (SDAPCD 2017).

There are very few air emissions sources currently in the project area and all are transient. Air emissions are currently generated from vehicle operations, most notably from USBP agents responding to cross border violations.

3.10.3      Environmental Consequences

The environmental consequences on local and regional air quality conditions near a proposed action are determined based upon the increases in regulated pollutant emissions relative to existing conditions and ambient air quality. Specifically, the impact in NAAQS “attainment” areas would

be considered significant if the net increases in pollutant emissions from the federal action would result in any one of the following scenarios:

• Cause or contribute to a violation of any national or state ambient air quality standard,
• Expose sensitive receptors to substantially increased pollutant concentrations,
• Exceed any evaluation criteria established by a SIP or permit limitations/requirements, and/or

• Emissions representing an increase of 100 tpy for any attainment criteria pollutant (NOx, VOCs, CO, PM10, PM2.5, SO2), unless the proposed activity qualifies for an exemption under the Federal General Conformity Rule.

Based on compliance with the NAAQS, the General Conformity Rule is only applicable in San Diego County to emissions of O3 and CO and as outlined in 40 CFR § 93.153(b), the applicable de minimis threshold for both pollutants is 100 tpy. While the General Conformity Rule is not applicable to emissions of the other criteria pollutants, it is being applied as a conservative measure of significance to determine the level of impacts under NEPA. The rationale for this conservative threshold is that it is consistent with the highest General Conformity de minimis levels for nonattainment areas and maintenance areas. In addition, it is consistent with federal stationary source major source thresholds for Title V permitting, which formed the basis for the nonattainment de minimis levels.

The Air Pollution Control District of San Diego County does not provide quantitative screening level thresholds for construction or mobile source-related impacts. However, the district does specify threshold levels for new or modified stationary sources. If a proposed action’s stationary source emissions are below these threshold levels, the proposed action’s impacts on air quality are presumed to be negligible to minor. Major, adverse impacts on air quality would also occur if the Proposed Action meaningfully contributed to the potential effects of global climate change.

3.10.3.1        Alternative 1: Partial Road Improvement

Alternative 1 would only generate temporary air pollutant emissions. The maintenance and repair activities associated with this alternative would generate air pollutant emissions because of grading, filling, compacting, trenching, and other activities; however, these emissions would be temporary and would not be expected to generate any offsite effects. Alternative 1 is not anticipated to result in a net increase in USBP traffic along the roadway. Therefore, the emissions associated with Alternative 1 from existing USBP traffic would not result in an adverse impact on local or regional air quality.

For the purpose of analysis in this EA, the total mileage of roadway for each alternative was obtained to estimate air emissions. Table 3-4 describes the approximate mileage and acreage that would be graded. Appendix H contains air quality emissions calculations for Alternative 1.

Table 3-4. Approximate Surface Area to be Graded During Maintenance and Repair Activities

Key: NA = not applicable Notes:

1. Area of land disturbance considered in this air quality analysis assumes the width of disturbance would be 24 ft multiplied by the length.
   1. Under the No Action Alternative, no construction or repairs would be conducted.

Criteria pollutant and GHG air emissions would be produced from the combustion of fuels in heavy equipment. Particulate matter air emissions, such as fugitive dust, would be produced from ground- disturbing activities and the combustion of fuels in heavy equipment. Fugitive dust air emissions would be greatest during the initial site grading and excavation and vary day to day depending on the work phase, level of activity, and prevailing weather conditions. The quantity of uncontrolled fugitive dust emissions from a construction site is proportional to the area of land being worked and the level of activity. Construction would incorporate BMPs and environmental control measures (e.g., wetting the ground surface) to minimize fugitive particulate matter air emissions. Additionally, work vehicles are assumed to be well maintained and use diesel particulate filters to reduce particulate matter air emissions. Workers and truck drivers commuting daily to and from the job site in their personal vehicles and heavy-duty diesel vehicles hauling grading and rock materials to the job site would also result in criteria pollutant and GHG air emissions.

Table 3-5 summarizes all criteria pollutant and GHG air emissions resulting from Alternative 1 as well as applicable thresholds. Criteria pollutant emissions from construction would be below the de minimis threshold of 100 tpy of each pollutant; therefore, impacts would be minor and a General Conformity determination (applicable to O3 and CO) is not required. Air Pollution Control District of San Diego County screening level thresholds do not apply to construction emissions. Detailed emissions calculations are provided in Appendix H.

The maintenance and repair activities associated with Alternative 1 would not have significant effects on regional or local air quality. Alternative 1 would generate emissions well below de minimis levels for all criteria pollutants in the SDIAQCR, and all emissions would be temporary.

Alternative 1 would contribute directly to emissions of GHGs from the combustion of fossil fuels from maintenance and repair activities and commuting of support personnel. CO2 accounts for 92 percent of all GHG emissions; transportation is the primary source of anthropogenic CO2, followed by electric utilities (CARB 2019).

Table 3-5. 2020 Estimated Construction Air Emissions from Alternative 1

Key: NA = not applicable Notes:

1 Lead, sulfates, hydrogen sulfide, and visibility reducing particulates emissions are not included as they are negligible for the types of emission sources under this Proposed Action.

2 General Conformity Rule de minimis thresholds or surrogate.

The U.S. Energy Information Administration (EIA) estimates that in 2017, gross CO2 emissions in the State of California were 358.6 million metric tons of CO2 equivalent (EIA 2019). The total annual CO2 emissions from Alternative 1 in California would be 275.43 metric tons, or less than

0.001 percent of the state CO2 emissions (see Appendix H). Therefore, Alternative 1 would represent a negligible contribution towards statewide GHG inventories.

Alternative 1 would emit approximately 275 tons of GHGs from construction during 2020. By comparison, 275 tons of carbon dioxide equivalent are approximately the respective GHG footprints of 14 single-family houses with two cars per home (USEPA 2017). As such, these increases and decreases of GHG emission rates would not meaningfully contribute or lessen the potential effects of global climate change (e.g., increases in atmospheric temperature, sea level, storm activity, accelerated coastal erosion, hydrological changes and flooding, and vegetation and wildlife changes).

As noted in Section 3.10.2, ongoing changes to regional climate patterns could increase average temperatures, alter precipitation patterns, and increase the frequency and severity of droughts in southern California (Garfin et al. 2014). However, even under severe drought conditions or during warmer temperatures, it is unlikely these ongoing climate change impacts would impair implementation of Alternative 1 or prevent CBP from fulfilling its mission.

3.10.3.2        Alternative 2: Complete Road Improvement

As with Alternative 1, Alternative 2 would generate only temporary air pollutant emissions. However, emissions from Alternative 2 would be greater than those of Alternative 1 due to the expanded section of roadway slated for improvement. Maintenance and repair activities would generate air pollutant emissions, but these emissions would be temporary and would not be expected to generate any offsite effects. As with Alternative 1, Alternative 2 is not anticipated to result in an increase of USBP traffic along the roadway and therefore would not result in an adverse impact on local or regional air quality.

Maintenance and repair activities would result in short-term emissions of criteria pollutants as combustion products from construction equipment. Emissions of all criteria pollutants would result from construction activities including combustion of fuels from on-road haul trucks transporting materials and construction commuter emissions. Fugitive dust air emissions would be greatest during the initial site grading and excavation and vary day to day depending on the work phase, level of activity, and prevailing weather conditions. The quantity of uncontrolled fugitive dust emissions from a construction site is proportional to the area of land being worked and the level of activity. Construction would incorporate BMPs and environmental control measures (e.g., wetting the ground surface) to minimize fugitive particulate matter air emissions. Additionally, work vehicles are assumed to be well maintained and use diesel particulate filters to reduce particulate matter air emissions. Construction workers commuting daily to and from the job site in their personal vehicles and heavy-duty diesel vehicles hauling construction materials to the job site would also result in criteria pollutant and GHG air emissions.

Table 3-6 summarizes all criteria pollutant and GHG air emissions resulting from Alternative 2 as well as applicable thresholds. Criteria pollutant emissions from construction would be below the de minimis threshold of 100 tpy of each pollutant; therefore, impacts would be minor and a General Conformity determination (applicable to O3 and CO) is not required. Air Pollution Control District of San Diego County screening level thresholds do not apply to construction emissions.

The maintenance and repair activities associated with Alternative 2 would not have significant effects on regional or local air quality, generating only short-term emissions well below de minimis levels for all criteria pollutants in the SDIAQCR.

Alternative 2 would contribute directly to emissions of GHGs from the combustion of fossil fuels from maintenance and repair activities and support personnel commuting. GHGs emissions from Alternative 2 would be expected to be greater than those from Alternative 1 due to the expanded section of roadway slated for improvement. The total annual CO2 emissions from Alternative 2 in California would be 437.17 metric tons, or less than 0.001 percent of the state CO2 emissions (see Appendix H). Therefore, Alternative 2 would represent a negligible contribution towards statewide GHG inventories.

Table 3-6. 2020 Estimated Construction Air Emissions from Alternative 2

Key: NA = not applicable Notes:

1 Lead, sulfates, hydrogen sulfide, and visibility reducing particulates emissions are not included as they are negligible for the types of emission sources under this Proposed Action.

b General Conformity Rule de minimis thresholds or surrogate.

3.10.3.3        Alternative 3: Preferred Alternative (Improve Drainage Features Without Widening Road)

Under Alternative 3, short- and long-term, negligible to minor, adverse impacts on air quality would be anticipated from emissions associated with combustion of fossil fuels, particulate matter, and fugitive dust emissions. Alternative 3 would be expected to result in similar or slightly greater impacts on air quality than Alternative 1 due to road widening.

Under the General Conformity Rule, a number of different federal activities are exempt. The exemption under 40 CFR 93.153(c)(iv) of the General Conformity rules states, “routine maintenance and repair activities, including repair and maintenance of administrative sites, roads, trails, and facilities” are exempt from General Conformity. All proposed activities associated with Alternative 3 are considered to be exempt under the General Conformity Rule.

Table 3-7 summarizes all criteria pollutant and GHG air emissions resulting from Alternative 3 as well as applicable thresholds. Criteria pollutant emissions from construction would be below the de minimis threshold of 100 tpy of each pollutant; therefore, impacts would be minor and a General Conformity determination (applicable to O3 and CO) is not required. Air Pollution Control District of San Diego County screening level thresholds do not apply to construction emissions.

Alternative 3 would contribute directly to emissions of GHGs from the combustion of fossil fuels from maintenance and repair activities and support personnel commuting. GHGs emissions from Alternative 3 would be expected to be similar to or slightly greater than those from Alternative 1 due to road widening. The total annual CO2 emissions from Alternative 3 in California would be

437.17 metric tons, or less than 0.001 percent of the state CO2 emissions (see Appendix H). Therefore, Alternative 3 would represent a negligible contribution towards statewide GHG inventories.

Table 3-7. 2020 Estimated Construction Air Emissions from Alternative 3

Key: NA = not applicable Notes:

1 Lead, sulfates, hydrogen sulfide, and visibility reducing particulates emissions are not included as they are negligible for the types of emission sources under this Proposed Action.

2b General Conformity Rule de minimis thresholds or surrogate.

3.10.3.4        Alternative 4: No Action Alternative

Under the No Action Alternative, CBP would not be maintaining, repairing, and improving the road. CBP enforcement actions would be maintained at current levels or diminish over time due to inaccessibility of the area to CBP agents. Therefore, no impacts no air quality would be expected from the implementation of the No Action Alternative because no maintenance or repair activities would occur in the project area.

3.11    NOISE

3.11.1      Definition of the Resource

Sound is a physical phenomenon consisting of vibrations that travel through a medium, such as air, and are sensed by humans (see Sections 3.5.3 and 3.6.3 for noise impacts to wildlife). Noise can be defined as unwanted sound that interferes with communication, poses a threat to health, or is irritating. Noise can be intermittent or continuous, steady or impulsive, and can involve anynumber of sources and frequencies. Response to noise varies depending on the type and characteristics of the noise, distance between the noise source and the receptor, receptor sensitivity, and time of day. Noise-sensitive land uses include areas where an excessive amount of noise would interfere with normal activities. Noise is often generated by activities essential to a community’s quality of life, such as construction or vehicular traffic.

Sound Metrics. Sound varies by both intensity and frequency. Sound pressure level, expressed in decibels (dB), is used to quantify sound intensity. Within the range of human hearing, a sound may vary in intensity by more than 1 million units. A logarithmic scale is used to compress the range of audible decibels into a more manageable form so that noise can be quantified. The A-weighted decibel (dBA) is used to characterize sound levels that can be sensed by the human ear. The threshold of audibility is generally within the range of 10 to 25 dBA for normal hearing. The upper boundary of audibility is 135 dBA and can be painfully loud (USEPA 1981). Sounds encountered in daily life and their dBA levels are provided in Table 3-8.

Table 3-8. Common Sounds and Their Levels

Source: Harris 1998

The sound pressure level noise metric describes steady noise levels. Very few noises are constant; therefore, additional metrics have been developed to describe noise. The day-night average A- weighted noise level (DNL) averages the sum of all noise-producing events over a 24-hour period. DNL is a useful descriptor for noise because it averages ongoing yet intermittent noise and measures total sound energy over a 24-hour period with penalties applied to noise levels during nighttime hours (County of San Diego 2016).

Regulatory Overview. The Noise Control Act of 1972 (Public Law 92-574) serves “to promote an environment for all Americans free from noise that jeopardizes their public health and welfare.” In San Diego County, residential, commercial and residential mixed-use, and agricultural land uses are compatible (acceptable) within areas with exterior DNL noise exposure levels at or below 60 dBA, at or below 65 dBA, and at or below 70 dBA, respectively (County of San Diego 2016). The San Diego County Code of Regulatory Ordinances relating to Noise Control and Abatement (County Noise Ordinance) states that it is unlawful for residential, agricultural, or civic uses within the A72 zone (i.e., zone for the proposed 1418 Firebreak Road improvement) to generate noise exceeding the 1-hour average sound level limits of 50 dBA (from 7 a.m. to 10 p.m.) and 45 dBA (from 10 p.m. to 7 a.m.). The County Noise Ordinance further states that construction equipment operations must not exceed an average sound level of 75 dB over an 8-hour period, between 7 a.m. and 7 p.m., or produce an impulsive noise that exceeds a maximum sound level in surrounding occupied properties (82 dBA for residential uses and 85 dBA for agricultural and commercial uses) for more than 15 minutes within a 1-hour measurement period.

Construction Sound Levels. Noise generated by construction activities has the potential to quickly surpass ambient sound levels. The type and intensity of the sound is dependent upon the type of construction activity taking place. The predicted noise levels for various construction equipment that might be used during Alternative 1 are presented in Table 3-9.

3.11.2      Affected Environment

The proposed project site is undeveloped and in a rural area. The surrounding area contains scattered residences, ecological reserve, wildlife refuge, and commercial businesses. Additionally, Johns Nichol’s Field Airport is located 0.33 miles west of 1418 Firebreak Road and contains one commercial business. Sensitive receptors in the vicinity include residences within approximately

2.3 miles of the footprint of the proposed 1418 Firebreak Road improvement.

3.11.3      Environmental Consequences

The impacts associated with noise were evaluated based on the changes to the ambient noise environment that would result from implementation of the Proposed Action. Impacts would be considered adverse if the Proposed Action were to result in the violation of applicable federal, state, or local noise regulations; or create appreciable areas of incompatible land use.

Table 3-9. Predicted Noise Levels for Typical Construction Equipment

Source: USEPA 1971

Note: Construction equipment equipped with noise control devices (e.g., mufflers) and use of sound barriers would result in lower noise levels than shown in this table.

3.11.3.1        Alternative 1: Partial Road Improvement

Construction. Construction noise from the proposed improvement to 1418 Firebreak Road would result in short-term, minor, adverse impacts on the ambient noise environment. Increases in noise levels would occur intermittently during construction. Noise from construction would vary depending on the type of equipment being used, the area in which the activity would occur, and the distance of the receptor from the noise source. Heavy construction equipment would be periodically used during construction; therefore, noise levels would fluctuate. Most equipment used would be expected to produce noise levels between approximately 70 and 100 dBA at a distance of 50 ft (see Table 3-9). Noise levels at the upper end of this range would be limited to intermittent spurts. Sound levels on the lower end of the range would be more constant during construction activities. These noise levels would decrease with distance from the construction area. Noise levels associated with typical construction equipment would noticeably attenuate to below 65 dBA between approximately 500 and 4,000 ft from the source, depending on the equipment used (see Table 3-9).

Construction activities usually require simultaneous use of several pieces of equipment. In general, the addition of a piece of equipment with identical noise levels to another piece of equipment would add approximately 3 dB to the overall noise environment, which is barely perceptible by the human ear (TRS Audio 2017). Cumulative noise associated with multiple pieces of construction equipment operating simultaneously would increase the overall noise environment by a few dB over the noisiest equipment, depending on the noise levels.

In addition, noise generation due to construction would be temporary, only lasting for the duration of construction activities, and would be isolated to normal workdays and working hours (i.e., weekdays 7 a.m. to 7 p.m.). All applicable noise laws and guidelines would be followed to reduce effects from noise produced by construction. Although the County Noise Ordinance does not apply to federal property, CBP would comply with the ordinance to the extent practicable. Construction workers would be required to use proper personal hearing protection to limit exposure and would use the appropriate noise attenuation equipment.

The nearest sensitive receptors (i.e., permanent residences within approximately 2.3 miles of the footprint of the proposed 1418 Firebreak Road improvement) would not be substantially impacted by temporary construction equipment noise. Even the loudest construction equipment, a paver, would register at 48-50 dBA 0.75 miles from the source. This is approximately the same sound level as rainfall (see Table 3-8). Construction equipment noise impacts on sensitive receptors would be minor because of the minimal cumulative contribution of the construction equipment to existing ambient noise levels from traffic and agricultural equipment; the distance of the residential receptors from the construction area; and the use of noise attenuation equipment to ensure that noise levels would not exceed an average of 75 dB over an 8-hour period. While existing noise sources produce elevated noise levels intermittently, noise during construction would be more continuous (with temporary increases in noise levels from the use of the loudest equipment) between the hours of 7 a.m. and 7 p.m.

Short-term, minor, adverse impacts on wildlife would occur as a result of temporary noise disturbances associated with construction and demolition activities. Loud noise can disturb wildlife resulting in escape or avoidance behaviors; however, these effects would be temporary. Noise can also distort or mask bird communications signals (e.g., songs, warning calls, fledgling begging calls) and their ability to find prey or detect predators. If noise persists in a particular area, animals could leave their habitat and avoid it permanently. Avoidance behavior by animals requires the expenditures of excess energy that is needed for survival (e.g., finding new food sources, water sources, and breeding and nesting habitats) (Ellis et al. 1991). Noises associated with construction and demolition would only be expected to affect individual animals within close proximity (typically within 400 to 800 ft) to the noise sources. Wildlife species would generally be expected to recover quickly from noise disturbance once the construction activities have ceased. As a result, population-level impacts would not be expected to occur.

Maintenance. Long-term, negligible, adverse impacts on the ambient noise environment would periodically occur during proposed maintenance activities, which would primarily occur within the footprint of the existing roadway. Maintenance crews would be required to use proper personal hearing protection to limit exposure and would use the appropriate noise attenuation equipment when necessary. Noise from maintenance activities would not impact areas outside of the proposed 1418 Firebreak Road improvement area or sensitive receptors. Impacts would be similar to those described for construction because similar equipment would be required. These maintenance activities would be temporary and intermittent; therefore, no major, adverse impacts would be expected.

3.11.3.2        Alternative 2: Complete Road Improvement

Under Alternative 2, impacts on noise receptors would be greater than Alternative 1 as the noise would occur over a longer distance and period of time. However, the noise from equipment used for maintenance and repair activities would not occur closer to sensitive receptors and would be localized, short-term, and intermittent during machinery operations and normal working hours. The proposed maintenance and repair activities would be expected to result in noise levels comparable to those indicated in Table 3-9.

3.11.3.3        Alternative 3: Preferred Alternative (Improve Drainage Features Without Widening Road)

Short-term and long-term impacts on noise receptors from Alternative 3 would be similar to those described for Alternative 1. Noise from equipment used for maintenance and repair activities would be localized, short-term, and intermittent during machinery operations and normal working hours. The proposed maintenance and repair activities would be expected to result in noise levels comparable to those indicated in Table 3-9.

3.11.3.4        Alternative 4: No Action Alternative

Under the No Action Alternative, CBP would not be maintaining, repairing, and improving the road. Therefore, no impacts on noise would be expected from the implementation of the No Action Alternative because no maintenance or repair activities would occur in the project area.

3.12    CULTURAL RESOURCES

3.12.1      Definition of the Resource

The term “cultural resources” refers to a broad range of properties relating to history, prehistory, or places important in traditional religious practices. Several federal laws and E.O.s, including the NHPA, the Archaeological and Historic Preservation Act (ARHA), the American Indian Religious Freedom Act (AIRFA), the Archaeological Resources Protection Act, and the Native American Graves Protection and Repatriation Act (NAGPRA) refer to cultural resources. The NHPA focuses on property types such as prehistoric and historic sites, buildings and structures, districts, and other places that have physical evidence of human activity considered important to a culture or a community for scientific, traditional, religious, or other reasons. These resources can prove useful in understanding and describing the cultural practices of past peoples or retain cultural and religious significance to modern groups. Resources judged significant under criteria established in the NHPA are considered eligible for listing in the National Register of Historic Places (NRHP). The NRHP refers to these places as “historic properties” and they are protected under the NHPA.

The NHPA requires federal agencies to consider the effects of their activities and programs on NRHP-eligible properties. Regulations for Protection of Historic Properties (36 CFR Part 800) present a process for federal agencies to consult with the appropriate SHPO, Native American groups, other interested parties, and when appropriate, the Advisory Council on Historic Preservation (ACHP). This is to ensure that the impacts from the undertaking are adequately considered on historic properties.

NAGPRA is a federal law passed in 1990 that provides a process for museums and federal agencies to return certain Native American cultural items—human remains, funerary objects, sacred objects, or objects of cultural patrimony—to lineal descendants, and culturally affiliated Indian tribes and Native Hawaiian organizations.

Under the CEQA, resources deemed historically significant through an assessment based on the California Register of Historical Resources (CRHR) set forth in Public Resources Code (PRC) § 5024.1, Title 14 California Code of Regulations (CCR) § 4852 are defined as historical resources. Historical resources are prehistoric and historic resources listed, or determined to be eligible for listing, in the CRHR, a resource included in a local register of historical resources (CCR, Title 14(3) § 15064.5[a][2]), or any object, building, structure, site, area, place, record, or manuscript that a lead agency determines to be historically significant (CCR, Title 14(3) § 15064.5[a][3]). The County of San Diego’s Resource Protection Ordinance defines “Significant Prehistoric or Historic Sites” as any resource formally determined eligible or listed in the NRHP by the Keeper of the National Register; one-of-a-kind, locally unique, or regionally unique cultural resources that contain a significant volume and range of data and materials; or any location of past or current sacred religious or ceremonial observances (County of San Diego 2016).

Under CEQA, Assembly Bill 52 recognizes tribal cultural values, in addition to scientific and archaeological values, when determining impacts and mitigation with a category of resources called tribal cultural resources (TCRs) (California OPR 2015); the California equivalent of TCRs. To qualify as a TCR, a resource must be listed, or determined eligible for listing, on the national, state, or local register of historic resources; or be a resource that a lead agency chooses to treat as a TCR based on the CRHR criteria and the cultural value of a resource to a California Native American tribe (PRC § 21074). To identify TCRs, lead agencies are required to consult with local Native American tribes in a manner that is cognizant of all parties’ cultural values and, where feasible, seeking agreement on a proposed action.

Prior to the start of field work, the California Native American Heritage Commission and BLM were consulted with a notice of intent to survey. On March 05, 2019, the Barona, Santa Ysbel, Campo, Inaja, Ewiiaapaayp, Jamul, Kwaaymii, San Pasqual, La Posta, Sycuan, Manazanita, Viejas, and Mesa Grande Native American communities were contacted with a notice of intent to survey. A final consultation letter for the California SHPO was prepared and sent to CBP on September 21, 2020. Concurrence was given by the California SHPO on November 25, 2020.

3.12.2      Affected Environment

The northern portion of 1418 Firebreak Road is depicted on the 1903 15’ 2º Cuyamaca USGS topographic map and originates from an unnamed road that follows the present-day path of Otay Lakes Road. The early 1418 Firebreak Road follows an unnamed creek that fed into the Lower Otay Reservoir. The 1943 Jamul 15’ map depicts 1418 Firebreak Road as an unimproved trail that follows the Little Cedar Canyon and Creek. In the 1955 Jamul 15’ USGS topographic map, 1418 Firebreak Road is clearly labeled as a “Jeep Trail.” Nearby, a land patent (homestead entry) was filed in 1891. This could be the origins of 1418 Firebreak Road.

Regional Prehistory. Prehistoric cultural chronology for the San Diego region subsequent to approximately 12,000 years ago is divided into three broad temporal periods: Paleoindian (San

Dieguito Complex), Archaic (La Jolla Complex/Encinitas Tradition), and Late Prehistoric. The sequence is based on syntheses by Rogers (1939, 1945, 1966); Wallace (1955, 1978); Moriarty (1966); Warren (1967, 1968); and True (1980), among others. There is no accepted evidence of occupation in this region prior to 12,000 years ago.

The San Dieguito Complex period dates from 9,030 to 8,000 years Before Present (B.P.) Sites from this period have been identified as part of the Western Lithic Co-Tradition or part of the Western Pluvial Lakes Tradition (Davis et al. 1969; Bedwell 1970). Occupants of most sites dating to this time period made use of coastal and inland resources. Artifacts include bifaces, knives, scrapers, cobble tools, and milling tools and bone tools used to process plants, shellfish, fish, birds, and small and large mammals.

The La Jolla Complex/Encinitas Tradition period dates from 8,600 to 1,300 years B.P. Doughnut stones, discoidals, stone balls, plummets, Elko-eared points and stone, shell and bone beads appear in this period and shellfish gathering decreases. Hunting tools initially consisted of the atlatl and dart but quickly advanced to bow and arrow. Most sites were in coastal areas.

The Late Prehistoric period dates from 1,300 years B.P. to historic contact. The cultures are divided into two groups: “San Luis Rey” (Shoshonean) in northern San Diego County and “Kumeyaay” (Yuman) in southern San Diego County. Sites from this period include ceramics, although Cuyamaca sites have a variety of type artifacts, such as pipes and effigies. Use of other traditional tools continues; marked differences between the two groups include Cuyamaca clay-lined hearths and cemeteries separate from living areas.

Ethnography. The project area is within the historical territory of the Kumeyaay, which extends from Northern San Diego County and south beyond Ensenada, Mexico (Campo 2018). The Kumeyaay were historically referred to as the Diegueño after Mission San Diego de Alcalá was established. The main language spoken is Hokan within the Yuman language family with dialects that are further broken into Tipai (southern) and Ipai (northern). The Takic-speaking Luiseño and Cahuilla live to the north (Loumala 1978).

The Kumeyaay were organized into autonomous bands based on family clans known as Sh’mulq which usually occupied a main village and several smaller habitation sites. Communities seasonally disbanded and established smaller groups of between 200 and 1,000 people to gather, process, and store resources. Subgroups spoke individual dialects and often intermarried (Campo 2018; Royo 1999).

As typical California seasonal hunters and gatherers, the Kumeyaay diet consisted mainly of plant foods, especially acorns, but also various other seeds and bulbs. This was supplemented by small game, including mammals and reptiles, and coastal inhabitants also had access to fish, shellfish, and sea mammals (Loumala 1978). Plants were also used for medicinal and ceremonial, as well as utilitarian, purposes. The medicinal use of plants covered a wide range of ailments, including European-introduced diseases such as syphilis, smallpox, and tuberculosis (Gallegos et al. 1998). Ceremonial usage included tattoos, girls’ puberty ceremonies, and rock art. A variety of objects were manufactured with plant materials, including houses, granaries, baskets, nets, adhesives, clothing, and soaps (Gallegos et al. 1998). The Kumeyaay maintained extensive trade networks as far east as the Colorado River, moving acorns, dried seafood, and seashells eastward and bringing salt, seeds, and mesquite beans west (Loumala 1978). The Jamul Indian Village, home of one of the federally recognized tribes of Kumeyaay people, is 8.6 miles north of the project area.

Regional History. The earliest explorations of the San Diego area began in 1542, when Juan Rodríguez Cabrillo and his party landed near Point Loma. Cabrillo had been tasked with the exploration of the interior of the western United States by the Spanish monarch. Interaction with the Kumeyaay was initiated, but overall little attention was given to California until the 1700s.

Spanish settlement of the San Diego area began in 1769 when the Spanish developed plans to build four presidios (forts), and three towns along the California coastline stretching from San Diego northward to Monterey. The town sites, established between 1777 and 1797, included present-day Los Angeles, San Jose, and a small town near Santa Cruz, named Branciforte. The presidios were established at San Diego, Santa Barbara, Monterey, and San Francisco. Under Spain, the “borderlands were colonized as defenses against the intrusion of the English, French, Dutch, and Russians, with the Manila trade an important item for protection in California. They were held by two typical institutions: the mission and the presidio” (Bolton 1913; 1921; 1930 as cited in Aviña 1976).

Mission San Diego Alcalá was also founded in 1769, the first of 21 Franciscan missions built along the coast on the El Camino Real, from San Diego to Sonoma. The goals of the missions were tri- fold: they helped establish a Spanish presence on the West Coast, allowed for a means to Christianize the native peoples, and served to exploit the native population as laborers. The missionaries, or padres, would essentially serve as a mayor, or head of the town. The Kumeyaay socio-political structure was severely disrupted by the Mission, especially those living closest to the grounds (Loumala 1978).

The arrival of the Spanish missionaries brought about prevailing changes for the Native Americans, including high mortality rates and social changes due to the introduction of European diseases and customs (e.g., European farming methods) (Dobyns 1983; Walker and Hudson 1993). Due to the high mortality rates, many Native American villages were abandoned, with inhabitants fleeing to the missions.

The Kumeyaay population decreased due to disease, revolts, and changes to their traditional ways of life. The San Diego Mission, however, was unique in that it allowed neophytes to move freely between the mission and traditional villages to hunt and gather food for the struggling mission. This allowed the Kumeyaay to experience a smaller population decline than Native Americans at other California missions. Those who did not return to the mission, however, were hunted as criminals (Carrico 2008).

Mexico gained independence from Spain in 1821 taking control of the lands Spain once held. The Secularization Act of 1833 transferred much of the mission lands to political appointees. Between 1840 and 1846, the Governors of California, Juan B. Alvarado, Manuel Micheltorena and Pio Pico, made a series of land grants, transferring Mission properties to private ownership (Cowan 1977; Ohles 1997).

In 1846, the Mexican-American War broke out in part because of American excursions into California. In 1847, General Andrés Pico and John C. Frémont signed the Articles of Capitulation,

ending hostilities between the United States and Mexico. The United States and Mexico signed the Treaty of Guadalupe Hidalgo, which resulted in Mexico ceding the lands of present-day California, New Mexico, and Texas to the United States for $15 million (Fogelson 1993:10). Within 2 years of the Treaty of Guadalupe Hidalgo, California applied for admission as a state.

Known Cultural Resources. In October 2019, Class III Cultural Resources Survey for the Proposed Improvement, Operation, Maintenance, and Repair Of the 1418 Firebreak Road Project in the Chula Vista Station Area of Responsibility of the U.S. Border Patrol San Diego Sector, San Diego County, California was completed (Cogstone 2019). According to the study, surveys occurred during April and May 2019 and included an intensive-level pedestrian survey of the project area with no larger than 49.21-feet-wide transects. Smaller transects were used in narrower areas of the project area and within previously recorded and newly discovered archaeological sites. There were seven sites previously recorded within the project area, including two prehistoric sites, two historic sites, two multi-component sites, and one site of indeterminate origin (rock feature). These sites were revisited and updated on California State Parks and Recreation Series (DPR) 523 forms. No artifacts were collected, and no resources listed or eligible for listing under NHPA are in the project area.

3.12.3      Environmental Consequences

Adverse effects on cultural resources can include physically altering, damaging, or destroying all or part of a resource; altering characteristics of the surrounding environment that contribute to the resource’s significance; introducing visual or audible elements that are out of character with the property or that alter its setting; neglecting the resource to the extent that it deteriorates or is destroyed; or selling, transferring, or leasing the property out of agency ownership (or control) without adequate legally enforceable restrictions or conditions to ensure preservation of the property’s historic significance.

Ground-disturbing activities associated with the implementation of the Proposed Action constitute the most relevant potential impacts on cultural resources.

3.12.3.1        Alternative 1: Partial Road Improvement

Under Alternative 1, ground-disturbing activities would occur within or adjacent to the existing footprint of the roadway (up to 24-feet wide in compliance with FC-2 design standards). If previously documented or newly discovered archaeological sites are found, mitigation measures (including avoidance of the sites) would be implemented. Alternative 1 would have negligible to minor adverse effects on cultural resources.

The potential exists for the unanticipated discovery of cultural resources or human remains during the maintenance and repair of roadway. Consequently, CBP would develop appropriate measures that detail crew member responsibilities for reporting in the event of a discovery during maintenance and repair activities. These measures would also include mitigation procedures to be implemented in the event of a significant unanticipated find. If human remains are discovered, CBP would adhere to the stipulations of Public Resources Code Section 5097.98 and Health and Safety Code 7050 and stop work within 50 ft of the discovery. CBP would then contact the county coroner and a professional archaeologist that meets the Secretary of the Interior’s Professional

Qualifications Standards in archaeology or history to determine the significance of the discovery. If appropriate, CBP would also adhere to NAGPRA and its implementing regulations (43 CFR 19). Depending on the recommendations of the coroner or the archaeologist, CBP would consult with the county to establish additional mitigation procedures. Potential mitigation procedures for unanticipated discoveries include avoidance, documentation, excavation, and curation. As a result, potential impacts on cultural resources discovered during the maintenance and repair of tactical infrastructure would be minor.

3.12.3.2        Alternative 2: Complete Road Improvement

Short- and long-term, negligible to minor, adverse impacts on cultural resources would be expected from the implementation of Alternative 2. Under this alternative, ground-disturbing activities would be more extensive than Alternative 1 and occur within or adjacent to the existing footprint of the roadway (up to 24-feet wide in compliance with FC-2 design standards). As with Alternative 1, if previously documented or newly discovered archaeological sites are discovered, mitigation measures would be implemented. Alternative 2 would have negligible to minor adverse effects on cultural resources.

3.12.3.3        Alternative 3: Preferred Alternative (Improve Drainage Features Without Widening Road)

Under Alternative 3, ground-disturbing activities would be confined to the existing footprint of the roadway. If previously documented or newly discovered archaeological sites are discovered, mitigation measures would be implemented. As a result, Alternative 3 would have a negligible to minor impact on cultural resources.

3.12.3.4        Alternative 4: No Action Alternative

Under the No Action Alternative, CBP would not be maintaining, repairing, and improving the road. Therefore, no impacts on cultural resources would be expected from the implementation of the No Action Alternative because no ground-disturbing activities would occur in the project area.

3.13    RECREATION AND ACCESS

3.13.1      Definition of the Resource

The term “recreation” refers to activities of leisure often done for enjoyment, amusement, or pleasure. Recreation is an essential part of human life and can be found in many different forms that are shaped by the interests of the individual, as well as their surrounding social construction. Public spaces, such as ecological reserves, wildlife refuges, and ranches are essential venues for many of these recreational activities. Tourist activities reflect that visitors are specifically attracted by the recreational activities that certain venues can offer. Therefore, recreation is an important factor in the economy, and outdoor recreation alone is among the nation’s largest economic sectors.

Outdoor recreation can include activities such as hiking, hunting, camping, horseback riding, wildlife viewing, and biking. According to the Wilderness Society, nearly 50 percent of all Americans—141.1 million people—participated in at least one outdoor activity in 2011, totaling to 11.6 billion outings. And in 2019, Americans enjoyed 1.5 billion more outings than the previous

year. It is estimated that outdoor recreational activity contributes roughly $730 billion to the economy of the United States (The Wilderness Society 2020).

3.13.2      Affected Environment

As stated in Section 3.2, land ownership of the project area includes various federal, state, and local agencies. The project area includes the OMER, San Diego NMR, Otay Mountain Wilderness, and Otay Ranch Preserve. While the BLM lands and San Diego NWR are not open to the public, the surrounding areas hold many different opportunities for recreational activities, including but not limited to hiking, hunting, camping, horseback riding, wildlife viewing, and biking.

Individuals seeking opportunities to engage in these activities occasionally use 1418 Firebreak Road for access. Along the road, there is a gate at which individuals have been known to park and leave their cars. Improvement of the roadway would temporarily close the road, resulting in decreased access for hikers and mountain bikers who would normally park along the road. Over the long-term, improving the road could potentially affect unauthorized mechanized activity in the wilderness.

3.13.3      Environmental Consequences

3.13.3.1        Alternative 1: Partial Road Improvement

Following the implementation of this alternative, 1418 Firebreak Road would be temporarily closed. Short-term, direct, minor to moderate impacts would occur from the temporary closure of the road. With the closure of the road, individuals would no longer be allowed to use the area near the gate as a makeshift parking lot, therefore temporarily decreasing access to public lands for recreational use. Long-term, indirect, negligible to minor impacts could occur from the improvement of the roadway, as formalizing the road may inadvertently encourage members of the public to access these areas as hiking or off-highway vehicle trails, due to proximity to the BLM wilderness and public lands.

3.13.3.2        Alternative 2: Complete Road Improvement

As with Alternative 1, 1418 Firebreak Road would be temporarily closed to the public with the implementation of Alternative 2. Short-term, direct, minor to moderate impacts would occur from the temporary closure of the road. These impacts would be expected to be greater than Alternative 1 as the complete roadway improvement would last longer than the partial roadway improvement. Construction would occur over a longer period of time and therefore result in a longer closure of the roadway. As with Alternative 1, under the road closure, individuals would no longer be allowed to use the area near the gate as a makeshift parking lot, therefore temporarily decreasing access to public lands for recreational use. Long-term, indirect, negligible to minor impacts could occur from the improvement of the roadway as formalizing the road may inadvertently encourage members of the public to access these areas more often for recreational purposes. Such impacts would be expected to be similar to impacts associated with Alternative 1.

3.13.3.3        Alternative 3: Preferred Alternative (Improve Drainage Features Without Widening Road)

Under this alternative, impacts on recreation would be expected to be similar to Alternative 1, as improvement activities under Alternative 3 are identical to Alternative 1 in all aspects except road widening.

3.13.3.4        No Action Alternative

Under the No Action Alternative, CBP would not be maintaining, repairing, and improving the road. CBP enforcement actions would be maintained at current levels or diminish over time due to inaccessibility of the area to CBP agents. The No Action Alternative would result in the continuation of individuals using the road to access public lands for recreational uses. No effects on recreation would be expected as a result of the No Action Alternative.

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4    CUMULATIVE AND OTHER IMPACTS

4.1        CUMULATIVE IMPACTS

CEQ defines cumulative impacts as the “impacts on the environment which result from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions regardless of what agency (federal or non-federal) or person undertakes such other actions” (40 CFR § 1508.7). Cumulative impacts can result from individually minor but collectively significant past, present, and foreseeable future actions. Informed decision-making is served by consideration of cumulative impacts resulting from projects that are proposed, under construction, recently completed, or anticipated to be implemented in the reasonably foreseeable future.

This cumulative impacts analysis summarizes expected environmental impacts from the combined impacts of past, current, and reasonably foreseeable future projects in accordance with CEQ regulations implementing NEPA and CEQ guidance on cumulative effects (CEQ 1997). The geographic scope of the analysis varies by resource area. For example, the geographic scope of cumulative impacts on resources such as soils and vegetation are narrow and focused on the location of the resource. The geographic scope of air quality and wildlife and sensitive species is much broader and considers more county- or region-wide activities. Projects that were considered for this analysis were identified by reviewing CBP documents; news releases and published media reports; the CEQAnet database; and publicly available information and reports from federal, state, and local agencies. Projects that do not occur in proximity (i.e., within several miles) of the proposed project site would not contribute to a cumulative impact and are generally not evaluated further.

4.1.1           Past, Present, and Reasonably Foreseeable Future Actions

Past actions are those within the cumulative impacts analysis areas that have occurred prior to the development of this EA. The impacts of these past actions are generally described in Section 3. Present actions include current or funded construction projects, CBP or other agency operations near the proposed site, and current resource management programs and land use activities within the cumulative impacts analysis areas. Reasonably foreseeable future actions consist of activities that have been approved and can be evaluated with respect to their effects. The following activities are present or reasonably foreseeable future actions:

Repair/Rebuild to FC-2 Minnewawa Road. The rebuilding and restoration of Minnewawa Road was designed to enhance officer safety by providing a more reliable and safe driving surface. The road is critical to USBP’s ability to maintain visual surveillance and communications capabilities in the vicinity of the project, and the road improvements were needed to ensure that the road is passable and to ensure officers’ safety. The entire 5.23 miles of roadway was rebuilt to FC-2 (all weather road) condition. Activities began November 2016 and the project was completed in November 2017.

Improvement of Otay Truck Trail. Otay Truck Trail East Road was an FC-2 level all-weather road not regularly maintained by CBP. The road had washed out in a number of locations, had lost much

of the drain-line ditches, and had a number of potholes as a result of water erosion and road washout. The project included the importing of roadway material to achieve a 6-inch-deep,well- graded roadbed, shaped with a defined crown section and included parallel ditches and cross culverts to ensure proper drainage both parallel and transverse to the road alignment. The improvement included repairs to 57 existing culverts of either 12, 18, or 24 inches in diameter of corrugated pipe. Some culverts were old and rusted, especially those 12 inches in diameter, and other culverts were clogged and/or collapsed. Activities began in September 2018 and the project was completed in January 2019.

Improvement and Widening of A-1 West Access Road. The project consisted of improving the westernmost 1,800 feet of the existing access road to an A-1 fence and border road. The project improved the road to a 24-foot-wide, all-weather road with appropriate drainage structures, including a low-water crossing and three culverts. The project required minor cut and fill work, grading, and adding an aggregate road base. A new turnaround area and the alignment shift in some sections of the road both caused disturbance outside of the existing road alignment. A utility pole was also relocated to outside the new road alignment. A locking gate along Alta Road at the turnoff to the improved access road was replaced. The project terminated to the west where the access road intersects Alta Road and to the east where it becomes Otay Mountain Truck Trail. The total project disturbance was 6 acres, of which approximately 4 acres were temporary disturbance and approximately 2 acres were permanent disturbance.

Improvement of the A-1 Border Road. The project consisted of improving approximately 5.4 miles of existing FC-3 road to a FC-2 all-weather road. The project also included cleaning out existing drainage ditches adjacent to the A-1 border road and repairing/replacing existing drainage ditches, rip-rap lining at inlet and outlet structures, and other ancillary drainage structures. The combined temporary and permanent footprint of the road improvements was approximately 24 feet wide in most of the project area.

Construction of San Diego Border Fence Replacement. The project replaced approximately 12.5 miles of existing secondary border wall, constructed approximately 1.5 miles of new secondary border wall (14 total miles), installed fiber-optic cable, and constructed an all-weather road along the southwestern border of the United States. The new taller and more substantial bollard-style wall that replaced the secondary wall is critical to prevent illegal entries into the United States and to achieve operational control of the border. The project included design, site preparation and material delivery, removal and replacement of the existing secondary wall, removal and replacement of existing motorized vehicle gates, installation of new fiber-optic cable, installation of grouted rip-rap, and construction of a 40-foot-wide all-weather road with electrical and lighting along 1.5 miles of new section of wall.

Construction of Brown Field Border Patrol Station. For this project, CBP proposed to construct, operate, and maintain a new USBP Brown Field Border Patrol Station on a 125.2-acre government- owned property in Dulzura, San Diego County, California. The project included construction of a main Border Patrol Station building designed to accommodate up to 400 USBP agents and support staff, as well as ancillary support facilities and structures including a vehicle maintenance/all- terrain vehicle storage facility, outdoor tactical support areas, government and privately owned vehicle parking areas, vehicle wash rack, fuel island, canine kennel, communications tower, septic

system and leach field, water supply facility, stormwater management system, helipad, roadways, emergency generators, and utilities.

State Route (SR) 905/SR 125/SR 11 Northbound Connector Project. This project is designed to help ease border congestion and facilitate goods movement between the United States and Mexico. New connectors at this critical link in the overall border road network provide direct access to SR 125 from SR 905 and SR 11. SR 905, a new six-lane, 6.4-mile highway that parallels Otay Mesa Road, opened to traffic in July 2012. Construction of the northbound connectors began in October 2015 and opened to traffic November 2016. This connector project is approximately 6 miles from the proposed project site.

SR 11 and Otay Mesa East Port of Entry. The purpose of this project is to meet expected, increased demand and reduce the impacts from idling vehicles at the existing border crossings in the bi- national San Diego-Baja California “mega region.” On both sides of the border, the project will create a network for the POE system that incorporates the latest security technologies with evolving border policies and procedures, including intelligent transportation management strategies, and serve as a model for a safe, secure, and efficient 21st Century POE. Under a plan approved in January 2012 by the California Transportation Commission, the United States portion of the project is being built in three segments. The first segment was completed and opened in 2016. This POE system would be approximately 6 miles from the proposed project site.

SR 94 Improvement Project. Caltrans is the lead agency for the SR 94 Improvement Project, which is funded by Jamul Indian Village and mitigates projected impacts on Highway 94 that are associated with the operation of the Hollywood Casino. The project consists of a series of improvement projects that include realigning and widening Highway 94 from north of Melody Road to south of Reservation Road, and five intersection improvements at Jamacha Boulevard and Jamacha, Steele Canyon, Lyons Valley, and Maxfield roads (Caltrans 2016). However, portions of the SR 94 Improvement Project would be at least 5 miles north of the proposed project site.

4.1.2           Cumulative Analysis by Resource Area

A cumulative impacts analysis must be conducted within the context of the resource areas. The magnitude and context of the impact on a resource area depends on whether the cumulative effects exceed the capacity of a resource to sustain itself and remain productive (CEQ 1997). The following discusses potential cumulative impacts that could occur as a result of implementing the Proposed Action and other past, present, and reasonably foreseeable future actions. No major, adverse, cumulative impacts were identified in the cumulative impacts analysis. Similar results would be expected with the implementation of Alternatives 1 and 3. Impacts resulting from the implementation of Alternative 2 would be expected to be greater than Alternatives 1 and 3, however the difference would not be significant. Meanwhile, implementation of the No Action Alternative could lead to moderate, adverse cumulative impacts due to further road deterioration.

4.1.2.1            Proposed Action

Implementation of the Proposed Action would ensure that the physical integrity of the existing road and associated supporting elements continue to perform as intended to assist the USBP in securing the U.S./Mexico international border in California. Improvement of the road would

enhance agent safety by providing efficient, reliable, and safe driving surfaces for USBP personnel. The Proposed Action would ensure the road is passable, providing faster response times to border incidents in strategically valuable areas. All maintenance and repair activities would occur via a periodic work plan. Implementation of the Proposed Action would not be expected to contribute to significant adverse cumulative effects. However, implementation would be expected to contribute to long-term, beneficial effects when effects from past projects such as Repair/Rebuild to FC-2 Minnewawa Road, Improvement of Otay Truck Trail, Improvement and Widening of A-1 West Access Road, and Improvement of the A-1 Border Road are considered. The combined roadway improvement projects would ensure that roadways used by USBP are passable, providing faster response times to border incidents in strategically valuable areas.

4.1.2.2            Land Use

Most of the project area is remote and predominately ecological reserve and wildlife refuge, most of which is managed or protected by the Federal Government. The maintenance and repair of tactical infrastructure would have no effect on land use plans or policies. Maintenance and repair activities involve work on existing infrastructure, so there would be no change in long-term land uses. Cumulatively, the Proposed Action and other maintenance and repair activities would not contribute to adverse effects on land use.

4.1.2.3            Geology and Soils

The potential for effects on geology and soils is limited to areas where ground disturbance would occur within the project area. The adoption of appropriate BMPs and proposed schedule for maintenance would ensure that erosion would be minimized, and erosion-creating activities well dispersed throughout the area avoiding any pockets of intense activity. Cumulatively, this approach reduces the impacts of any ad hoc approach applied to past maintenance and repair activities and ensures future potential erosion is well-managed.

Consequently, the maintenance and repair of 1418 Firebreak Road combined with other present construction activity, including Construction of Brown Field Border Patrol Station, SR 94 Improvement Project, and State Route 11 and Otay Mesa East Port of Entry, would be expected to result in short-term, minor, adverse effects that are localized to the areas where ground disturbance has occurred. Long-term, beneficial effects would be expected from stabilization of the roadway and drainage structures in the project area.

4.1.2.4            Vegetation

Minor to moderate effects on native species vegetation and habitat and introduction of non-native species are observable from past and present development and land use. Selective maintenance and repair activities would be expected to result in generally negligible adverse effects on terrestrial and aquatic vegetation. Under the work plan, BMPs would ensure impacts on vegetation including the introduction of non-native species would be minimized, and consequently the cumulative effects on vegetation resources would be considered negligible.

4.1.2.5            Terrestrial Wildlife Resources

Minor to moderate effects on wildlife species have occurred from the additive effects of past and present actions, although there is quality habitat surrounding the project area to support wildlife. Maintenance and repair activities would be expected to result in generally negligible, adverse effects on wildlife and aquatic species. Operation of heavy equipment would generate temporary noise and could displace wildlife species. Under the work plan, BMPs would ensure impacts on terrestrial and aquatic wildlife resources would be minimized and therefore the cumulative impacts on terrestrial and aquatic wildlife resources would also be considered to be negligible in effect.

4.1.2.6            Threatened and Endangered Species

As discussed in Section 3.6, CBP has formally consulted with USFWS under Section 7 of the ESA regarding potential effects on listed species and designated critical habitat. Potential direct and indirect effects on federally listed species presented in this EA are based on currently available data. A separate effects analysis is developed under NEPA, but parallels impact determinations made for the Section 7 consultation process. The designation of threatened or endangered implies that past activities have had major adverse effects on these species.

There are three federally listed threatened or endangered plant or animal species that are known to occur within the region of analysis and one other federally listed species that has a high potential to occur in the project area. Section 3.6 presents detailed discussions for each of these species. Cumulatively, present and future activities are likely to continue to affect threatened and endangered species. Potential threats include habitat loss from urbanization and road construction, trampling of protected plants, corridor fragmentation, and noise from increasingly urban areas. The ESA will continue to protect threatened and endangered species and designated critical habitat with the goal of recovery. Short-term, cumulative adverse impacts from Construction of Brown Field Border Patrol Station, SR 94 Improvement Project, and State Route 11 and Otay Mesa East Port of Entry would be expected, as construction for all four projects would be occurring at the same time. However, cumulatively, the Proposed Action would be expected to have negligible to moderate contributions to adverse effects on threatened and endangered species.

4.1.2.7            Hydrology and Groundwater

Water quality of the Imperial Valley Groundwater Basin, the main aquifer in the project area, has historically been adversely affected by surrounding land uses and water withdrawals. The Proposed Action does not involve new development activities; negligible, indirect, adverse effects could occur on hydrology and groundwater systems from the maintenance and repair of roadways and drainage management structures. Cumulatively, effects on hydrology and groundwater from the maintenance and repair of the roadway in addition to other projects would also be negligible.

4.1.2.8            Surface Waters and Waters of the United States

Surface water quality of sub-watersheds within the project area have historically been significantly affected by various inputs including urban, agricultural and livestock runoff, and septic, wastewater, and industrial discharges. Some surface water bodies are consequently on USEPA’s 303(d) list of impaired waters, as discussed in Section 3.8 (USEPA 2010d). Historically significant wetland losses have resulted from draining, dredging, filling, leveling, and flooding for agricultural

and urban development. California has lost as much as 91 percent of its original wetlands, primarily from conversion to agriculture (USGS 1996).

The Proposed Action does not involve new development activities, but negligible, indirect, adverse effects could occur on surface waters from the maintenance and repair of the roadway and drainage management structures. Under the work plan, BMPs would ensure impacts on surface water and ephemeral drainages are minimized. Cumulatively, effects on surface waters and Waters of the United States from the maintenance and repair of the roadway would be negligible in the short- term but with the consistent observance of the work plan could result in long-term, minor, beneficial impacts on surface water quality.

4.1.2.9            Floodplains

Floodplain resources can be adversely impacted by development, increases in impervious areas, loss of vegetation, hydrological changes, and soil compaction. Historically, natural floodplains have been permanently altered by development activities and the construction of canals and reservoirs. The Proposed Action does not involve new development activities and would have no direct effects on floodplains. Clearing of vegetation and removal of debris could result in increased sedimentation into floodplains and drainage structures, but this would be a negligible indirect effect. Cumulatively, effects on floodplains from the maintenance and repair of the roadway, in addition to other projects, would be negligible.

4.1.2.10        Air Quality

USBP San Diego Sector operates within an AQCR that is in nonattainment for one or more criteria pollutants. The Proposed Action would have short-term, negligible, localized, adverse effects on air quality during maintenance and repair activities. The adoption of appropriate BMPs and proposed schedule for maintenance would ensure that dust creation would be minimized. Cumulative effects on local and regional air quality from the maintenance and repair of the roadway, in addition to other projects, would be negligible.

4.1.2.11        Noise

Cumulative effects on the noise environment occur when a project has noise emissions that are noticeably loud or that raise ambient noise levels. New noise sources are generally more noticeable in areas that have lower ambient noise levels. Cumulative effects on noise would only be expected where multiple projects are occurring at the same time and in the same vicinity because noise attenuates over distance. Short-term, cumulative adverse impacts from Construction of Brown Field Border Patrol Station, SR 94 Improvement Project, and State Route 11 and Otay Mesa East Port of Entry would be expected as construction for all four projects would be occurring at the same time.

The Proposed Action would have short-term, negligible to minor, localized adverse effects as a result of the operation of heavy machinery to maintain and repair the roadway. Maintenance and repair of roadway in remote areas would be distant from most other substantial noise-generating activities, so there is little potential for cumulative effects. Increased noise from operation of machinery could combine with existing noise sources or other construction-type activities to produce a temporary cumulative effect on sensitive noise receptors. The adoption of appropriate

BMPs and proposed schedule for maintenance would ensure that noise would be minimized. Consequently, existing noise sources would continue to dominate the noise environment and, cumulatively, effects on the noise environment from maintenance and repair of the roadway, in addition to other projects, would be negligible to minor.

4.1.2.12        Cultural Resources

Historically, long-term, major, adverse effects on cultural resources have likely occurred from the destruction or alteration of resources before their significance was realized. Tactical infrastructure construction for those projects identified in Section 1.1 was performed under the supervision of cultural resources specialists to ensure known cultural resources would be protected and that any unanticipated discoveries would be identified and coordinated with the appropriate federal, state, or tribal parties. The cumulative effects on cultural resources from the maintenance and repair of past, present, and foreseeable future tactical infrastructure projects when considered in conjunction with the Proposed Action would be negligible since all activity would occur within previously disturbed or environmentally cleared footprints.

4.1.2.13        Recreation and Access

The Proposed Action would temporarily close 1418 Firebreak Road to the public. Short-term, minor to moderate impacts would occur from the temporary closure of the road as individuals would no longer be allowed to use the area near the gate as a parking lot. Long-term, negligible to minor impacts would occur from the improvement of the roadway. Improvement of the road could draw more individuals to use 1418 Firebreak Road for access to these public lands for recreation. Cumulatively, effects on recreation and access from the maintenance and repair of the roadway would be minor to moderate when combined with possible impacts from other projects occurring at the same time, including Construction of Brown Field Border Patrol Station, SR 94 Improvement Project, and State Route 11 and Otay Mesa East Port of Entry.

4.1.2.14        No Action Alternative

Under the No Action Alternative, CBP would not be maintaining, repairing, and improving the road. As discussed in Section 3, generally, the No Action Alternative would be expected to have no impacts on soils, vegetation, terrestrial and aquatic wildlife, threatened and endangered species, groundwater, surface water and Waters of the United States, floodplains, air quality, noise, cultural resources, or recreation and access. Under the No Action Alternative, maintenance and repair work would not be completed. Under such conditions, there is also a greater likelihood of road degradation occurring beyond the proposed footprint with a corresponding potential to adversely affect cultural resources and species habitat that have not been previously surveyed. Effects on land use under the No Action Alternative would be the same as effects under the Proposed Action.

Cumulative effects on soils, vegetation, terrestrial and aquatic wildlife, threatened and endangered species, groundwater, surface water and Waters of the United States, floodplains, air quality, noise, cultural resources, and recreation and access under the No Action Alternative would be expected to be less adverse than those discussed under the Proposed Action. Cumulative effects on land use would be essentially the same as those discussed under the Proposed Action. Implementation of the No Action Alternative would not, however, be expected to contribute to significant adverse,

cumulative effects when considered with other recently completed or planned future projects in the project area.

4.2        RELATIONSHIP BETWEEN THE SHORT-TERM USE OF THE ENVIRONMENT AND LONG-TERM PRODUCTIVITY

Short-term uses of the biophysical components of the human environment include direct construction-related disturbances and direct impacts associated with an increase in population and activity that occurs over a period of less than 5 years. Long-term uses of the human environment include those impacts that occur over a period of more than 5 years, including permanent resource loss.

As the proposed improvement, maintenance, and repair activities would be confined to the existing footprint of 1418 Firebreak Road, very little permanent impact would occur. The impact resulting from the installation of the turnout would, however, permanently remove a portion of the natural resources in the area, such as vegetation and wildlife habitat.

4.3        CEQA FINDINGS OF SIGNIFICANCE

This EA was prepared to comply with NEPA, but also meets the requirements of CEQA. Use of the term “significant” to describe impacts differs under these two laws. Under NEPA, an EA is prepared to determine whether an action as a whole (i.e., adverse and beneficial impacts) would have a significant impact on the environment based on context and intensity and, if no unmitigable significant impact would occur, then a FONSI is prepared. Whereas, CEQA requires a determination of each significant impact on the environment resulting from the action. Due to these differences, the determination of significant impacts under CEQA have not been specifically addressed in other sections of this EA.

Section 15382 of the CEQA Guidelines defines a significant impact on the environment as “a substantial, or potential substantial, adverse change in any of the physical conditions within the area affected by the project.” This definition underlies the analysis of environmental impacts for most of the impact issues identified in the CEQA Environmental Checklist Form (CEQA Guidelines Appendix G). Using these significance criteria, it was determined that the Proposed Action would not result in unavoidable significant impacts under CEQA with implementation of the BMPs and mitigation measures identified in Appendix D of this Final EA. Table 4-1 identifies the CEQA findings of significance for each resource area identified in the CEQA Environmental Checklist Form, and the EA section in which detailed analysis for each resource area is located.

4.4        GROWTH-INDUCING IMPACTS

Section 15126.2(d) of the CEQA Guidelines defines growth-inducing impacts as “the ways in which the project could foster economic or population growth, or the construction of additional housing, either directly or indirectly, in the surrounding environment.” These projects include those that would remove obstacles to population growth (e.g., major expansion of wastewater treatment plant) and those that could encourage and facilitate other activities that could significantly affect the environment.

The Proposed Action would not result in an intensification of land use or remove any barriers to growth in the area surrounding the project corridor. Implementation of the Proposed Action is not anticipated to encourage additional growth in the area because 1418 Firebreak Road is not a public road and is only intended for use by CBP. Additional limitations to growth in the vicinity include the presence of federally-, state-, and locally-protected lands as the project corridor falls within the boundaries of OMER, San Diego NWR, Otay Ranch Preserve, and BLM public lands.

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6    LIST OF PREPARERS

David Boyes

M.S. Natural Resource Science

B.S. Applied Biology Years of Experience: 43

Nicolas Frederick

M.S. Biology

B.S. Psychology

Years of Experience: 10

Hannah Kopydlowski

B.S. Biology

Years of Experience: 4