A trio of U.S. senators has asked the Government Accountability Office to review the National Park Service's spending habits and recommend ways the agency can save money.

The request, sent Monday by Sens. Tom Coburn of Oklahoma, Mike Enzi of Wyoming, and Lisa Murkowski of Alaska, states that the ever-growing maintenance backlog for the National Park System needs to be reversed.

"Last year alone, the National Park Service delayed more than a quarter-billion dollars in much needed maintenance projects, adding another substantial sum to the over $11.5 billion deferred maintenance backlog already threatening the health, safety, and accessibility of park visitors," the three wrote. "To address this serious problem, we have been exploring various avenues to work towards reducing the maintenance backlog, including a comprehensive review of the National Park Service's administrative structure."

While the three Republicans don't cite in the letter what avenues they've been exploring, their request to the GAO seeks:

* "A formal review of the National Park Service's administrative structure to identify and address any inefficiencies, redundancy, and opportunities for administrative savings;"

* "A review of the Recreation Fee program within the National Park Service, including a report detailing the NPS' expenditure of fee receipts and a review of how spending prioritization decisions are made," and,

* "Options for how the National Park Service can reduce its current Deferred Maintenance Backlog, including identification of underutilized revenue sources and suggestions for improving revenue streams."

National Park Service officials did not immediately respond to the question of whether they welcome this review.

In a press release announcing the GAO request, Sen. Enzi said public access to the parks often has been impeded, in the Park Service's opinion, by insufficient funding.

“Our national parks are important to Wyoming and to me personally. I want to see them preserved, but I also want people to be able to access and enjoy them," he said. "The trend has been to lessen public access and often the justification is that there isn’t enough money to keep things open. Yet, we’ve never been able to tell where all the money is really going. This review should give us a good idea."

Wyoming's senior senator said the review could take a year or longer, but that "“it’s been a long time coming."

Last fall, Sen. Coburn issued a report, Parked! How Congress' Misplaced Priorities Are Trashing Our National Treasures, that blamed both the Park Service and Congress for the state of the National Park System. In that report he described an overly bureaucratic National Park Service as a cumbersome agency that spends more on administration and overhead than on the parks themselves.

"... only half of the funds appropriated by Congress even go to the park superintendents, while the national headquarters and regional offices consume more of the NPS budget than facility maintenance projects," the report charged. "Beyond the staff and funding at the individual park units, there is an expansive amount of administrative and specialty support offices and programs.

"In total, the NPS budget provides $455 million to regional and service-wide support offices," the report illustrated. "In comparison, the 59 National Parks representing the 'crown jewels' of the park system receive $442 million in annual general operation and maintenance funds. An additional $168 million is needed for external administration costs such as space rental, postage, and centralized IT costs."

The senator's findings and contentions drew disagreement from the National Parks Conservation Association as well as the Coalition of National Park Service Retirees, two groups that advocate on behalf of the National Park Service and park system.

"To casual readers or to reporters on tight deadlines unfamiliar with the workings of the National Park System and the budgetary process – it would be easy to think that Coburn offers a multitude of factual information, at times even seemingly compelling info, along with his self-prescribed solutions," Joan Anzelmo, a former park superintendent and now a member of the Coalition, said at the time. "However, one has to really understand how national parks operate, how the budget process works and how certain funding sources cannot simply be transferred from one authorized use to something Coburn thinks would be a better use of funds.

"... Every criticism and every solution is framed by Coburn to appear reasonable and persuasive but in fact requires cooperation within Congress and the passage of several new laws and new budget formulas," she added in an email. "It is hard to imagine a Congress as dysfunctional as exists now could ever get to the legislation that would be required for the Coburn solution."

At NPCA, Kristen Brengel shared the senator's concern over the Park Service's staggering maintenance backlog, a backlog Congress has contributed greatly to through its budgeting actions

"There are a number of troubling trends the American public has observed in the last several years – the National Park Service budget hasn’t kept pace with inflation and in the last three years we have witnessed a major decline in National Park Service funding," Ms. Brengel, the organization's senior director of legislative affairs and government relations, wrote in an email. "This year was the third straight year of budget cuts for the National Park Service; most recently the sequester added insult to injury.

"The FY13 cut was a full 8 percent -- or more than $180 million -- below last year in today’s dollars. The funding available to operate our national parks is 13 percent below three years ago," she noted.

"The deferred maintenance backlog is nearly $12 billion and growing; the most critical projects have a $4.5 billion backlog. Over the last decade, the park construction budget has declined by nearly 70 percent in today’s dollars. Senator Coburn’s report doesn’t point out this trend, which is a symptom of the failed Congressional budget process."