In an internal memo circulated within the Interior Department earlier this year, government scientists issued a stark warning: The Trump administration’s plans to allow oil exploration in Alaska’s Arctic National Wildlife Refuge could further jeopardize the region’s already fragile polar bear population. The document, authored in September by the head of the state’s US Fish and Wildlife Service office, noted that the threat posed to the bears could make it legally challenging for the agency to authorize a series of seismic surveys of the area’s petroleum reserves—even if steps were taken to mitigate the project’s environmental impact. The memo, obtained by Mother Jones from a source outside of the Alaska office, describes its finding as a “preliminary analysis” based on “information currently available to us.” That analysis contrasts sharply with the administration’s public rhetoric suggesting that the project would be harmless and should therefore be quickly approved. “With as few as 900 of these animals remaining, even the death of one polar bear from fossil fuel development is too many,” said Jenny Keatinge of Defenders of Wildlife. The surveys of ANWR’s coastal plain—which would require convoys of 30-ton thumper trucks equipped with massive off-road tires, along with hundreds of support vehicles and crew members—are expected to begin as early as January or February.