Earlier this month, in a decision faced with much controversy, the Biden administration approved the “Willow Project,” one of the most significant oil developments on federal land.

The Willow Project is a large, decades-long oil drilling venture on Alaska’s North Slope in the National Petroleum Reserve-Alaska (NPR-A), owned by the federal government.

The NPR-A was created in the 1920s to provide a future oil supply for the U.S. Navy between the 1940s and 1980s. The federal government then drilled several explorative wells in the area but did not find commercial quantities of oil. This led to Congress authorizing competitive oil and gas leases in the NPR-A.

ConocoPhillips, the Houston-based energy company responsible for the plan for the Willow Project, has held oil and gas leases to develop oil for the region in the NPR-A since the area’s first lease sale in the 1990s. Conoco discovered “Willow” in 2013, drilled two successful exploratory wells in 2016, and now estimates that the site holds around 600 million barrels of oil (currently more than the amount currently held in the U.S. Strategic Petroleum Reserve).

The Trump Administration had approved Conoco’s proposal for five drilling sites in the area. However, judges struck down the proposal, citing improper planning and environmental concerns. After several years of permitting and legal battles, and despite activists aggressively protesting the project, the Biden administration has now approved the project, with restrictions, allowing Conoco to have up to three drilling sites, with up to 199 total wells, to reduce its carbon impact.

The controversy of the Willow Project stems not only from its significant cost, estimated to be between $8 billion to $10 billion, but also from the possibility of prolonging the country’s reliance on fossil fuels and its carbon contribution to the environment. However, supporters say that new oil from Alaska will produce billions of dollars of income for the state and federal governments through increased revenue from oil, gas royalties, and taxes while helping to safeguard the U.S. against a return to dependence on foreign oil.