WildEarth Guardians and Sierra Club v. United States Bureau of Land Management

The Bureau of Land Management (BLM) approved four coal leases in Wyoming's Powder River Basin (North Hilight, South Hilight, North Porcupine, and South Porcupine) to extend the life of two existing surface mines: Black Thunder and North Antelope Rochelle. These mines account for approximately 19.7% of U.S. annual domestic coal production. The leases contain approximately two billion tons of recoverable coal and would extend mine operations by 4-9 years. In its Environmental Impact Statement (EIS) and Records of Decision (RODs), BLM concluded that issuing the leases would not result in higher national carbon dioxide emissions than declining to issue them, assuming that if the leases were not issued, the same amount of coal would be sourced from elsewhere (the "perfect substitution assumption"). WildEarth Guardians and Sierra Club challenged this conclusion, arguing BLM failed to adequately compare alternatives as required by NEPA and ignored basic supply and demand principles. Three of the four leases had already been issued and mining had commenced by the time of the appeal.

• Whether BLM's assumption that declining to issue coal leases would not impact national coal consumption or carbon dioxide emissions (perfect substitution assumption) was arbitrary and capricious under the Administrative Procedure Act
• Whether BLM complied with NEPA's requirement to take a 'hard look' at environmental consequences and provide a meaningful comparison of alternatives
• Whether environmental organizations had Article III standing to challenge climate change analysis based on local aesthetic and recreational injuries
• Whether BLM was required to use economic modeling tools (NEMS) to assess market impacts
• What remedy is appropriate when an agency violates NEPA

The Tenth Circuit REVERSED the district court's decision upholding the leases and REMANDED with instructions to enter an order requiring BLM to revise its Environmental Impact Statement and Records of Decision. The court did not vacate the resulting leases, leaving questions about appropriate injunctive relief and the status of ongoing mining operations to be determined by the district court on remand.

An agency acts arbitrarily and capriciously under the Administrative Procedure Act when it relies on an economic assumption that: (1) lacks support in the administrative record; (2) contradicts basic economic principles of supply and demand; and (3) is central to distinguishing between alternatives in a NEPA analysis. When an agency assumes perfect market substitution without analyzing price effects, supply constraints, or market impacts of removing a substantial portion (20%) of national production, the agency fails to take the required 'hard look' at alternatives and defeats NEPA's purposes of informed decision-making and public disclosure. Local aesthetic and recreational injuries are sufficient to confer standing to challenge an agency's climate change analysis when the challenged decision would be vacated if plaintiffs prevail, even if the specific injury is not climate-related.

Judge Baldock's concurrence expressed concern about the majority's unnecessary commentary on whether climate science is "settled science," noting this issue was not before the court since BLM had conceded that coal use causes climate change. He emphasized the case turned on basic economic principles, not scientific expertise, and cautioned that courts should decide only matters properly before them. Judge Baldock also suggested that if climate science questions were at issue, courts should defer to agencies given judges' lack of scientific resources. The majority also discussed but did not decide: whether BLM's failure to use available modeling tools (NEMS) independently violated NEPA (concluding agencies have discretion in methodology); and noted that choosing between conflicting scientific evidence is generally left to agencies, though this principle does not apply when an assumption lacks any evidentiary support.

This case is significant in U.S. environmental law (and potentially relevant for South African courts considering similar issues) because it: (1) establishes that agencies cannot rely on unsupported economic assumptions that contradict basic market principles when comparing NEPA alternatives; (2) clarifies that environmental organizations may challenge climate change analysis based on local injuries without proving climate-specific harm; (3) demonstrates that courts will not defer to agency expertise when agencies provide conclusory statements without supporting analysis; (4) shows that assumptions central to distinguishing between alternatives must be supported by record evidence; and (5) illustrates how courts balance environmental protection with practical realities when mining operations have already commenced. The case represents a significant judicial check on agency discretion in the context of fossil fuel leasing on federal lands and climate change analysis under NEPA.