Pombo proposed legislation to sell roughly a quarter of the land managed by the National Park Service. In November 2005, Pombo and Jim Gibbons (R-NV) co-authored an amendment to the Federal Budget Reconciliation Bill easing restrictions of sale of federal lands to mining companies. This amendment was opposed by environmentalists, anti-growth advocates, and even some Republican Senators concerned about the measure's effects on hunting and fishing. The amendment narrowly passed the House, but was defeated in the Senate. The legislation was later described by his chief of staff as a "bureaucratic exercise" designed to evaluate the costs of not drilling in the Arctic National Wildlife Refuge (ANWR).