MONTE CRISTO — The old townsite here and the popular hiking trail leading to it are likely to be off-limits this summer as a cleanup that’s been in the works for more than a decade finally begins.

The U. S. Forest Service plans to close the area to the public starting April 15, though the paperwork still is being finalized, said Joseph Gibbens, the on-site coordinator for the clean-up. The destination would not reopen until at least the end of October, he said.

For the past two years, crews have worked on a new road leading to the townsite so they can haul in equipment. That was finished in 2014. The Forest Service has been planning the project since 2003, Gibbens said.

“As we move into this season, this is going to be our big clean-up year,” he said.

Over the summer, a crew of about 15 people is tasked with building a repository near the mining ghost town — essentially an on-site landfill. It will be used to contain tailings contaminated with toxic metals, namely arsenic and lead.

The tailings were left behind after the mining boom from 1889 to 1920, according to the Forest Service. The valuable ore was hauled away and the remains were left in Monte Cristo. Some metals in those remnants can be poisonous if consumed by humans or other animals. The cleanup is meant to protect hikers who picnic in the area and fish that swim in the South Fork Sauk River, Gibbens said.

There are seven sites that need to be excavated, he said. Five are near the town, including the old processing facility. Anywhere the ore was extensively handled is on the list. Two sites are outside of town: the nearby Rainy Mine and the Pride of the Woods Mine farther up Glacier Creek. Helicopter crews are needed for the work at Pride of the Woods, Gibbens said.

Most of the metal waste is going to the repository, but some has to be hauled out separately because the amount of toxic metals reaches state-mandated “dangerous waste” levels.

The project is being paid for by money from a bankruptcy settlement for Asarco — originally the American Smelting and Refining Company. About $5.5 million of the settlement is going toward the Forest Service’s clean-up efforts around the mines.

After the project is done, the Forest Service and state Department of Ecology plan to continue monitoring the Monte Cristo area. The new road will be maintained for that, and hiking or bicycling should be allowed, Gibbens said. However, he doubts the road would open for driving to the scenic ghost town.

The picnic area where most people stop to eat and explore is not part of the area that will be excavated and cleaned, Gibbens said.

“We’re going to do our best to leave the historical artifacts intact and work around them during the clean-up,” he said.

The Forest Service plans to release more details about this year’s work in the next couple weeks, and additional information about the project is available online at www.1.usa.gov/1Gw3bmA.

Kari Bray: 425-339-3439, kbray@heraldnet.com