DARRINGTON, Wash. (AP) — The U.S. Forest Service has given the green light to install new seismometers on Glacier Peak, classified as one of the most dangerous volcanoes in the United States.

There’s only one monitor there now, according to federal agencies. More early warning sensors could provide precious time to evacuate, the Everett Herald reported.

The U.S. Forest Service determined the project would have no significant impact on the environment. Two groups opposed the use of helicopters in a wilderness area. The Forest Service considered a “full range of alternatives” in making the decision to move forward. Crews carry equipment in backpacks, cutting down on flight time.

The U.S. Geological Survey can start installing four new monitors and upgrade the old one, as part of a 30-year special use permit. Government officials estimate the GPS stations could detect eight times as many earthquakes.

The seismometers could be installed as soon as this summer. But the work might not happen until at least next year, according to USGS.

Glacier Peak is one of the region’s most active volcanoes. About 13,000 years ago, the volcano blew off five times as much rock as the 1980 explosion of Mount St. Helens.

Washington’s hidden Glacier Peak volcano is among the most dangerous

The Forest Service estimates 11,000 people visit the Glacier Peak Wilderness annually.