EPA Administrator Lee Zeldin is facing a pivotal decision that could have far-reaching consequences for the agency’s ability to regulate climate pollution. President Donald Trump has given Zeldin one week to determine whether the EPA should abandon its authority to regulate greenhouse gas emissions under the Clean Air Act. This decision could potentially lead to a monumental fight over the agency’s role in reducing carbon emissions, with implications that extend beyond Trump’s presidency.
The key issue at stake is the endangerment finding, a 2009 scientific determination that forms the basis for all greenhouse gas regulations. This finding asserts that greenhouse gas emissions pose a threat to public health and welfare, providing the legal foundation for rules targeting pollutants like carbon dioxide and methane. If Zeldin moves to overturn this finding, it could pave the way for the dismantling of numerous climate regulations put in place under President Joe Biden, while creating legal obstacles for future administrations seeking to address climate change.
While challenging the endangerment finding could be a risky move, some believe it is necessary to prevent further regulation of greenhouse gases. Myron Ebell, who led Trump’s EPA transition team, expressed confidence that Zeldin could make the right decision. However, the potential implications of such a decision are significant, with industry groups warning that it could lead to a wave of lawsuits and regulatory uncertainty.
The first Trump administration opted not to challenge the endangerment finding, but it remains unclear how Zeldin will proceed. Some industry groups support retaining the finding, as it gives EPA the authority to regulate climate change. However, conservative organizations like the Competitive Enterprise Institute have long advocated for its removal, citing legal challenges and regulatory burdens.
The outcome of this decision could impact the future of climate policy in the United States. If the endangerment finding is overturned, it could streamline the process of rolling back existing regulations on greenhouse gases. However, it could also result in legal challenges that consume valuable time and resources. Ultimately, Zeldin’s decision will shape the EPA’s approach to climate change and set the stage for future administrations to address this critical issue. The recent rulemaking by the EPA has sparked controversy surrounding the use of the social cost metric as a tool for measuring the impact of climate change. In a bold move, the EPA has taken the social cost metric off the table, raising concerns about how the agency will address climate emissions moving forward.
According to experts like Ebell, undoing the 2009 finding that established the social cost metric does not necessarily mean challenging scientific findings on climate change. Instead, the EPA could argue that the Clean Air Act is not equipped to effectively address climate emissions. This argument could be supported by pointing to the failure of past power plant carbon rules, including those implemented during Trump’s first term.
However, environmental lawyers have pointed out that courts have previously rejected claims by the EPA that it can choose not to issue an endangerment finding based on factors other than scientific evidence. Past administrations, like the George W. Bush administration, have made similar arguments to avoid regulating greenhouse gases, but these arguments were dismissed by the Supreme Court in the landmark case Massachusetts vs. EPA.
The scientific consensus on the link between carbon emissions and climate-related disasters has only strengthened in the years since the Massachusetts vs. EPA ruling. This consensus is reflected in the National Climate Assessment, a report that Trump has hinted at influencing. Despite this, the EPA has reaffirmed the endangerment finding in rulemakings since 2009, making it difficult for the agency to now argue that climate change is not a serious threat.
As the debate over the social cost metric continues, it is clear that the EPA faces a challenging road ahead. The agency must navigate the legal and scientific complexities of addressing climate change while also considering the implications of its past decisions. The outcome of this rulemaking will have far-reaching effects on environmental policy and the future of climate action in the United States.
This article is a rewritten version of a piece originally published on E&E News, with permission from POLITICO, LLC. Copyright 2025. E&E News is a trusted source of news for energy and environment professionals.
