Boundary Enlargement of the San Gabriel Mountains National Monument

President Biden enlarged the San Gabriel Mountains National Monument by approximately 105,919 acres using the Antiquities Act, expanding protections to additional federal lands in the Angeles National Forest south and west of the existing monument boundary. The proclamation directs the Secretary of Agriculture, through the Forest Service, to manage the expansion area and develop a management plan in consultation with the Secretary of the Interior, Tribal Nations, Indigenous peoples, and other stakeholders. The expansion withdraws the reserved federal lands from entry, sale, mining, and mineral/geothermal leasing, while incorporating by reference the management terms of President Obama's original 2014 proclamation.

Federal Register Open PDF 89 FR 40361

Impact dates

Date TBD
Management plan development and implementation
Jul 31, 2024
Secretary to establish advisory committee

Key directives

Expand San Gabriel Mountains National Monument by approximately 105,919 acres
Secretary of Agriculture, through Forest Service, shall manage expansion area
Secretary shall prepare management plan in consultation with Secretary of the Interior
Management plan must include provisions for continuing outdoor recreational opportunities
Management plan must provide for protection and interpretation of objects of scientific and historic interest
Secretary shall establish advisory committee under 5 U.S.C. chapter 10
Maximum public involvement required, including Tribal Nation consultation and Indigenous engagement
Incorporate Indigenous Knowledge to maximum extent practicable
Secretary shall promulgate rules and regulations for expansion area management
Federal lands withdrawn from all forms of entry, location, selection, sale, or disposition under public land laws
Withdrawal from location, entry, and patent under mining laws
Withdrawal from disposition under mineral and geothermal leasing laws

Who is ordered

Timeline

Immediate

Monument boundary expansion takes effect upon proclamation
Federal lands withdrawn from entry, location, sale, mining, and mineral/geothermal leasing

Near term (90d)

Secretary of Agriculture to establish advisory committee under FACA
Initiation of management plan development with consultation requirements

Long term

Management plan completion and implementation
Ongoing protection of historic, scientific, cultural, and ecological objects
Continued recreational access to the extent consistent with protection objectives
Potential future federal land acquisitions automatically reserved as monument lands

Risks & tensions

Potential conflicts between recreational access and protection of objects of historic/scientific interest
Tension between mineral/geothermal industry interests and permanent withdrawal from leasing/entry
Vague timeline for management plan completion creates implementation uncertainty
Indigenous Knowledge protection requirements may conflict with standard federal disclosure practices
'Smallest area compatible' finding may face legal challenge given 105,919-acre expansion
Proclamation incorporates by reference 2014 proclamation terms without re-evaluating their adequacy