PUBLIC LANDS WATCH

Chaco Culture National Historical Park (Greater Chaco Landscape)

San Juan County, northwestern New Mexico · National Historical Park; UNESCO World Heritage Site. Threat concerns the surrounding 10-mile buffer under BLM jurisdiction · managed by National Park Service (park); Bureau of Land Management (surrounding buffer)

Status: Proposed — public comment period closed, decision pending Threat: Oil and gas drilling — mineral withdrawal revocation
Coordinates
36.0608, -107.9556
Page last verified
2026-08-12
Site maintainer of record
Alicen M.
File
/chaco-culture

01 — Historical & Cultural Record

Chaco Canyon was a major ceremonial and cultural center for the ancestral Puebloan world between roughly 850 and 1250 A.D. It holds continuing living significance for today's Pueblo communities, the Hopi Tribe, the Navajo Nation, and other Indigenous nations. Chaco Culture National Historical Park is a UNESCO World Heritage Site, containing great houses, kivas, and other structures such as Pueblo Bonito. After nearly a decade of advocacy by tribes, archaeologists, and conservation groups, and a public process spanning about 1.5 years with 150 days of public comment, the BLM established Public Land Order 7923 in June 2023, withdrawing approximately 336,404 acres within a 10-mile radius of the park from new mineral leasing and mining claims for 20 years.

02 — Current Threat

On October 30, 2025, the Interior Department began tribal consultation on a proposal to reverse Public Land Order 7923. On March 31, 2026, the BLM opened a public scoping/comment period — initially just seven days, later extended, closing July 29, 2026 — on a proposal to revoke the withdrawal and reopen the 336,404-acre buffer to oil and gas leasing. The BLM's own environmental assessment reportedly found under 1% of the buffer area has meaningful oil and gas development potential. Navajo Nation President Buu Nygren has publicly supported ending the buffer, citing financial harm to Navajo allottees within the zone, while the Pueblo of Acoma and the All Pueblo Council of Governors have opposed the rollback.

03 — Documented Impact: Environmental

Geology & Land Use Context: Chaco sits within the San Juan Basin, one of the most intensively developed oil and gas regions in the country. Roughly 90% of the broader Greater Chaco landscape outside the 10-mile buffer is already leased for oil and gas development, meaning the buffer represents most of what remains unleased in the immediate region.

Climate & Air Quality: The San Juan Basin has been identified by NASA satellite methane mapping as the single largest regional methane anomaly ("hot spot") in the continental United States — a roughly 2,500-square-mile methane cloud, comparable in size to the state of Delaware, spanning the Four Corners region including national parks like Chaco. Estimates have put the value of natural gas lost annually to flaring and venting in the region above $2 billion. Methane traps roughly 84 times more heat than CO2 over its first 20 years in the atmosphere. Independent USGS field measurement (983 flux-chamber readings, 2022-2023) confirmed natural geologic seepage exists along specific fault-associated outcrops in the basin, distinct from — and smaller than — the oil-and-gas-driven emissions documented by satellite.

Air Quality & Public Health: Approximately 75% of San Juan County residents live within a half mile of oil and gas infrastructure, and many are documented to suffer respiratory illness and other poor health outcomes tied to air pollution from existing operations. Weakening the 10-mile buffer would extend this same industrial footprint closer to the park itself.

Night Sky / Visual Resources: Chaco is documented for exceptional dark-sky quality; existing gas flares in the surrounding basin already light up the night sky, and expanding drilling into the buffer would further degrade the dark-sky and viewshed experience across the 91,793-acre area immediately visible from the park.

Cultural/Archaeological (overlapping with land disturbance): Archaeologists estimate as many as 12,000 cultural sites and traditional cultural places may lie within the 5-to-10-mile zone, though only 15-20% of the area has been surveyed; ground disturbance from drilling risks damaging sites before they are even identified.

Long-Term Effects: A National Parks Conservation Association program manager has characterized the proposal as risking "a thousand years of history" — framing the loss as non-recoverable given the buffer protects both undiscovered archaeological resources and the visual/atmospheric integrity of a landscape with a documented history of prior societal collapse tied partly to environmental stress (a historical drought is cited as a factor in the original Chacoan community's dispersal circa 1150-1250 A.D.).

03 — Documented Impact: Cultural & Archaeological

See combined cultural/archaeological detail folded into the environmental section above.

03 — Documented Impact: Economic & Fiscal

A prior single BLM lease sale bordering the buffer area generated $3 million in bids. The BLM's own environmental assessment for the 2026 revocation reportedly found under 1% of the buffer area has meaningful oil and gas development potential, raising the question of how much additional tax or royalty revenue the revocation would realistically generate relative to the cultural and tourism value of the UNESCO World Heritage Site it would expose to drilling. Separately, New Mexico's oil and gas sector overall employs nearly 20,000 people statewide and contributed $2.2 billion to state coffers in the most recent reporting year (roughly half the state's general fund) — context for the industry's broader economic weight in the state, though not a figure specific to the 336,404-acre buffer itself. A dedicated fiscal comparison study specific to the buffer was not identified in current sourcing.

03 — Documented Impact: Legal Status

As of this page's last verification, the BLM had not issued a final decision on the proposed revocation following the close of the public comment period on July 29, 2026.

03 — Documented Impact: Human Health

Approximately 75% of San Juan County residents live within a half mile of oil and gas infrastructure, and this population is documented to suffer respiratory illness and other poor health outcomes linked to air pollution from existing operations (see environmental section); expanding drilling into the buffer would extend this same industrial footprint closer to areas with documented resident exposure.

03 — Tribal / Public Consultation Status

The Interior Department began tribal consultation on reversing PLO 7923 on October 30, 2025. The subsequent public comment period was initially set at just seven days (March 31, 2026) — a sharp contrast to the original withdrawal's 1.5-year process with 150 days of public comment — before being extended to close July 29, 2026. Navajo Nation leadership and Pueblo/All Pueblo Council of Governors leadership have taken opposing public positions on the underlying policy, both engaging with the consultation process but reaching different conclusions.

04 — Named Companies & Responsible Parties

05 — Recorded Opposition & Support

06 — Timeline of Developments

07 — Sources

Primary

Secondary

Corrections Log

None on record as of 2026-08-12 (page last substantially expanded).

Take Action

Public comment period closed July 29, 2026; final BLM decision pending as of last verification.

Sign / comment on the public record for Chaco Culture National Historical Park (Greater Chaco Landscape) →