WASHINGTON — Federal agencies would no longer have to take climate change into account when they assess the environmental impacts of highways, pipelines and other major infrastructure projects, according to a Trump administration plan that would weaken one of the benchmark environmental laws of the modern era.
The proposed changes to the 50-year-old National Environmental Policy Act could sharply reduce obstacles to the Keystone XL oil pipeline and other fossil fuel projects that have been stymied when courts ruled that the Trump administration did not properly consider climate change when analyzing the environmental effects of the projects.
The act requires the federal government to prepare detailed analyses of projects that could have significant environmental effects, including long-term impacts that courts have said include climate change. The law has only been amended once since it was enacted in 1970.
But the Trump administration has been aggressive in its efforts to roll back environmental regulations long considered sacrosanct. The 50 or so pages of revisions that the White House Council on Environmental Quality is expected to make public on Wednesday would mark the first major changes to the law in three decades.
According to one government official who has seen the proposed regulation but was not authorized to speak about it publicly, the administration will more narrowly define the type of project that requires an environmental review. That could make it likely that more projects will sail through the approval process without having to disclose effects like hazardous waste discharges, the removal of trees or increased air pollution.
The new rule also would no longer require agencies to consider the “cumulative” consequences of new infrastructure. In recent years courts have interpreted that requirement as a mandate to study the effects of allowing more planet-warming greenhouse gas emissions into the atmosphere. It also has meant understanding the impacts of rising sea levels and other results of climate change on a given project.
Once the proposed rules are filed in the federal register, the public will have 60 days to comment on them, the official said. A final regulation is expected before the presidential election in November.
A spokesman for the Council on Environmental Quality did not respond to a request for comment on the proposed regulation.
President Trump’s latest effort to eliminate regulations on industry appears also to be a play to win over construction trade unions that have long complained that the National Environmental Policy Act has tied up energy and transit projects that create jobs.
“The environmental review process designed to improve decision-making has become increasingly complex and difficult to navigate,” Mr. Trump said in a presidential message on New Years Day to mark the 50th anniversary of the act.
He criticized the “significant uncertainty and delays that can increase costs, derail important projects, and threaten jobs for American workers and labor union members” and said the revisions would “benefit our economy and environment.”
Environmental activists and legal experts said the proposed changes would weaken critical safeguards for air, water and wildlife. The move, if it holds up in court, also could eliminate a powerful tool that climate change activists have used to stop or slow Mr. Trump’s encouragement of coal and oil development as part of its “energy dominance” policy.
In March, a federal judge found that the Obama administration did not adequately take into account the climate change impact of leasing public land for oil gas drilling in Wyoming, a ruling that also presented a threat to Mr. Trump’s plans for fossil fuel development.
One month later, another federal judge dealt a blow to Mr. Trump’s plan to lift an Obama-era moratorium on coal mining on public lands when he found the administration did not adequately study the environmental effects of mining as required by law.
And in 2018, a federal court cited the environmental policy act when it halted construction on the Keystone pipeline, a project President Trump has been determined to see become a reality. The court said the Trump administration had failed to justify reversing the Obama administration’s ruling that the pipeline would unduly worsen climate change. The case is still under litigation.
The Trump administration “simply discarded prior factual findings related to climate change to support its course reversal,” Judge Brian Morris of the United States District Court for Montana wrote at the time.
Michael Gerrard, director of Columbia University’s Sabin Center for Climate Change Law, said eliminating the need to consider climate change would lead to more pipelines and other projects that worsen global emissions. It could also put roads, bridges and other infrastructure at greater risk, he said, because developers would not be required, for instance, to analyze whether sea-level rise threatened to eventually submerge a project.
“It has the potential to distort infrastructure planning by making it easier to ignore predictable futures that could severely degrade the projects,” Mr. Gerrard said.
With the proposed changes, said Brett Hartl, government affairs director for the Center for Biological Diversity, “You’re assuming away massive amounts of harm and you’re not even going to discuss it.”
But Michael Bridges, president of the Longview-Kelso Building and Construction Trades Council in Washington State, said he was eager to see the law revised. He said groups opposed to fossils were using the environmental policy act to tie up a major coal export terminal in the state.
“We had everything from singing grandmas to people dressed up as endangered species coming in,” Mr. Bridges said of public hearings on the terminal.
A state analysis concluded that the terminal would allow 22 million more tons of carbon dioxide emissions into the atmosphere over its projected 20-year life span. Mr. Bridges said he wanted strong environmental laws, but ones that take the local economy into consideration. The coal terminal, he noted, would replace an old aluminum smelter that shuttered in 2001, eliminating about 1,500 jobs.
“That was a big hit for us,” he said. “I’m living in these communities, I’m building these projects, and we want them to be safe. The reason this is effective for environmental groups is that they’re able to keep timing it out until the businesses run out of money to fight it or it doesn’t make sense anymore.”
While Mr. Trump may not be known for deep involvement in policy matters, one administration official said the president, as a former real estate developer, was familiar with the National Environmental Policy Act and has expressed keen interest in the law’s revisions. In one of his earliest environmental announcements, Mr. Trump signed an executive order to speed permitting for infrastructure, complaining that building a highway can take up to 17 years because of what he called burdensome regulations.
Mr. Gerrard said the environmental review requirements of New York’s state-level version of the environmental policy act had helped to defeat a golf course that Mr. Trump hoped to build in Mount Kisco, N.Y. The Seven Springs golf course would have abutted Byram Lake, a reservoir for drinking water. Mr. Gerrard, who represented opponents of the project, said environmental reviews enabled the community to show that the drinking water supply could have been endangered. Mr. Trump shelved the project in 2004, but his public comments indicate the episode still rankles.
In a speech to the National Association of Realtors in May, Mr. Trump told an appreciative crowd: “I was building a development. I was going to build some really luxury, beautiful houses.” But, he said: “I found out that I can’t build on the land. Does that make sense to you?”