From barren to beautiful at Aspen’s Hope Mine

ASPEN – Taking root at the toxic Hope Mine reclamation site near Aspen are tall grasses and signs of growth that have the organizations behind the cleanup project excited. Before the recent environmental work, the area was a toxic, barren slope.

“This project is going better than I would have dared hoped,” John Bennett, executive director of For the Forest, an Aspen-based nonprofit focused on forest health, said Thursday during a press conference at the site.

The reclamation of the slope, south of Aspen in the Castle Creek Valley, became more pressing when it was discovered that very low levels if toxic metals had been sliding into the creek, a source of Aspen’s drinking water.

Even though the levels of toxins were minute, the reclamation plan was intended to prevent a potential landslide on a mine tailings pile – debris left from mineral extraction – that could add poisons into the creek.

“The Forest Service turned us on to the project because it’s their land,” said Kate Holstein, program director of For the Forest. “They told us there is a situation where this big slope is continually eroding into Castle Creek. … If a large erosion were to occur where the whole slope slid into the creek, it could be catastrophic.”

Holstein said such a landslide could shut down the Castle Creek water source potentially for years.

For the Forest entered into a partnership with the Carbondale-based Flux Farm Foundation and the U.S. Forest Service to reclaim the site beginning in October 2010, planting a mix of native grasses on the pile.

The key ingredient to the experiment was biochar, which Morgan Williams, president of Biochar Solutions and executive director of the Flux Farm Foundation, described as dehydrated wood. The benefits of mixing the charcoal-like substance with soil is that it acts as a fertilizer, though it’s not one. And, its production sequesters carbon, preventing it from entering the atmosphere.

Biochar can be developed from the trees killed by the mountain pine beetle epidemic, which has devastated swaths of national forest in Colorado.

Williams, born and raised in the Roaring Fork Valley, has been testing the effect of adding biochar to the soil at the former mine site, located along the side of Aspen Mountain, which extends south from the ski area that faces town.

Forty-two test plots were laid out at the site; each contains different variations of biochar mixed with soil and seeds, as well as control plots that contain no biochar. Williams said there are significant differences between the plots, and that biochar is making growth happen.

Scott Snelson, Forest Service ranger in the Aspen and Sopris districts, said the Hope Mine project has been more efficient than the other potential approaches, which included excavation of most of the slope.

“We knew that the project wouldn’t drive the risk to zero, but at least we had a chance to get something started in the spring that could hang on to part of the slope.” Snelson said.

Excavation of the entire site is still a possibility, according Snelson.

“We need to reclaim this site,” Snelson said. “This was an emergency project with hope that we could hold the slope opposed to excavating out the contours.”