Bringing the 88,900-acre Valles Caldera National Preserve under National Park Service management could increase visitor numbers and boost the local economy, according to a new study from the federal agency.

The preserve is a good candidate to include in the National Park System because of its national significance as one of the best preserved examples of a resurgent volcano and the probability it could be managed more cost efficiently out of nearby Bandelier National Monument.

Several groups hailed the study as one more reason Congress should move the preserve's management from the Valles Caldera Trust to the National Park Service.

"We are most encouraged by the National Park Service emphasis on local economic benefits that would result from NPS management," said Tom Ribe, executive director of Caldera Action, in a statement.

Caldera Action has been pushing for more than a year to have the Valles Caldera become a preserve within the National Park Service. The Valles Caldera Preserve was purchased by Congress in 2000 and is managed by the Valles Caldera Trust — overseen by a board appointed by the president. The trust operates independently of other federal agencies under specific mandates to protect resources, operate a working ranch, promote recreational use and become financially self-sufficient by 2015. Ribe and others think the "land management experiment" at Valles Caldera has failed.

Gary Bratcher, executive director of the Valles Caldera Trust since January 2009, thinks the trust can substantially meet the Congressional mandates by the deadline.

New Mexico Sens. Jeff Bingaman and Tom Udall asked the National Park Service last summer to conduct a feasibility study. The report was submitted to the senators Dec. 29.

The report said it is difficult to know the total cost of operating the Valles Caldera as a National Park preserve without a long-range plan. Two similar size parks — Great Sand Dunes National Park and Guadalupe Mountains National Park, have staff sizes similar to the Valles Caldera, but operate on less money. Great Sand Dunes received $2.2 million in federal funds in 2008 and Guadalupe Mountains received $2.7 million. The Valles Caldera Trust received $3.6 million from Congress and collected $700,000 in revenues, primarily from hunting, fishing and other recreation. "Each park has unique needs and circumstances, so comparisons of this sort are not an entirely reliable indicator of funding or staffing needs for a potential new park," according to the study.

In terms of visitors, the parks are worlds apart. Valles Caldera counted 17,000 visitors in 2008. Great Sand Dunes had 273,900 and Guadalupe Mountains reported 197,767 visitors. The trust is working on a long-range public access and land-use plan and depending on the results, "there could be major changes in the level of unstructured access, development and visitor use opportunities provided on the Preserve," according to the NPS study.