Six men face federal charges for allegedly driving into and damaging an area of Black Hills National Forest land near Spearfish that is off limits to motor vehicles.

U.S. Attorney Marty Jackley said Ryan Heggem, Kyle Burg, Drew Fredricksen, Nicholas Sukstorf, Kirk Jenkins and Brandon Schmidt have all been indicted by a federal grand jury. Jackley said a juvenile also is involved in the case but said he could not comment about whether the juvenile will face charges.

The six men are facing one count of felony depredation of government property and a misdemeanor charge of prohibited use of vehicles off-road, Jackley said.

The men's hometowns and ages cannot be released yet, he said.

The depredation charge carries a maximum sentence of 10 years in prison and a $250,000 fine. The misdemeanor charge has a maximum penalty of one year in jail and $10,000 fine.

The suspects allegedly drove their vehicles into a muddy Johnston Gulch southwest of Spearfish on June 14 and got stuck.

Weeks of heavy rainfall in the Northern Hills had caused the ground to soften considerably. The drivers of the vehicles allegedly left ruts causing erosion in an area of Johnston Gulch between Tinton Road and Higgins Gulch, about 5 miles from Spearfish.

They are accused of driving past warning signs indicating that vehicle travel was prohibited in the area, according Black Hills National Forest spokesman Frank Carroll. Officials found five vehicles stuck in mud at the site.

Carroll said the damage was much more severe than it would have been during the past few summers, which were dry and hot.

"This has been a very wet year," he said. "In very dry years, they may not do the same amount of damage. They probably wouldn't."

He said the vehicles ripped through plant life and destroyed the relatively thin layer of topsoil in the area.

"When people use their vehicles to injure or destroy that soil profile in a way that we lose that topsoil, it's a big loss," he said.

Large ruts also make the area more susceptible to erosion, Carroll said.

A final damage estimate has not been determined, according to Jackley. He said that more than $1,000 in damage was done, however, which is why the felony depredation charge was filed.

Representatives from the Northern Hills Ranger District could not be reached Friday afternoon to provide an update on repairs to the damaged forest land.

Contact Ryan Woodard at 394-8412 or ryan.woodard@rapidcityjournal.com