Interior Secretary Ryan Zinke announced the creation of a new advisory panel on recreation Tuesday that will focus on better ways to exact fees from national park visitors and make sure the fees go toward improving park infrastructure.

Zinke drew criticism last month when he proposed doubling entrance fees at 17 national parks to raise revenue for maintenance. Sen. Lisa Murkowski, R-Alaska, chairwoman of the Senate Energy and Natural Resources Committee, said the proposal has caused her concern and is open to a hearing on the issue.