In the face of intense public interest, much of it critical, the National Park Service is giving people more time to weigh in on its controversial proposal to boost entrance fees to $70 per vehicle at its most popular parks, including four in Utah.

The Interior Department has long struggled with a maintenance backlog that now totals nearly $12 billion at its national parks, with buildings, roads, bathrooms and sundry visitor facilities in a state of disrepair. In October, Interior Secretary Ryan Zinke proposed restructuring visitor fees, nearly tripling them at 17 marquee parks during the busy months spanning summer.

The idea drew strong rebukes from a bipartisan array of lawmakers and 60,000 comments during the first one-month comment period. Many complained that $70 would pose a serious obstacle for many families who have to spend so much just to get to places like Yosemite, Yellowstone and Glacier national parks.

“There are so many barriers already,” said Jes Ward, executive director of the Denver-based youth-engagement organization cityWILD. “A lot of folks who may struggle with income and transportation, they already feel it’s expensive. Increasing the fee increases the barriers. A lot of low-income families won’t stay for a week, so it really is a daily use fee.”

The Park Service is now accepting comments for a second month, until Dec. 22, as it weighs whether to implement the proposal, amend it or abandon it in favor of solutions that don’t rely so heavily on visitors. The plan targets 17 busy parks, including Utah’s Arches, Canyonlands, Bryce Canyon and Zion, during their five busiest months, when vehicles would be charged $70 for a week-long pass, less for those on motorcycles, bicycles and foot. For the rest of the year, the parks’ regular fees, typically $25 or $30, would apply.

Park Service officials estimated the fee revision would generate up to $70 million in additional revenue, which Zinke says would be used to repair parks’ aging infrastructure, such as the Washington Monument’s elevator.

In the meantime, President Donald Trump is seeking a 13 percent cut to to the Park Service’s $3 billion budget, potentially costing up to 1,200 jobs, despite three straight years of record visitation, reaching 331 million nationwide last year.