From Aspen Journalism (Curtis Wackerle):

You wouldn’t want to put it in your granola, in the words of Crystal Valley Environmental Protection Association President John Armstrong, but a heap of waste material left over from a 1900s smelting operation near the banks of the Crystal River in Marble does not appear to pose enough of an environmental hazard to prevent the donation of 55 acres of otherwise stunning, mostly wetlands terrain to a land conservation organization.

But the road to reach this point has been long for the private owner of the now three contiguous parcels across the river that the owner has been trying since 2016 to see donated and permanently preserved in its natural state. In that time, concerns about potential liabilities associated with the slag pile have held up the initiative.

But support from CVEPA, which agreed to put $1,000 toward an analysis of the material, plus a discussion with the Pitkin County Health Rivers and Streams board about a grant, gave momentum to the effort last year. This spring, the Colorado Department of Public Health and Environment (CDPHE) completed its analysis of the site and determined that contaminant levels in the material are within the range considered to be non-threatening to human health for a day-use recreation site.

In the end, the analysis work was completed pro bono, and proponents hope that funds pledged can be used for materials to fence off the slag heap and put up some interpretive signage explaining the history of the smelter and the slag left behind. This would complement an eventual management framework in which a land-conservation agency holds title to the property and allows passive, non-motorized public access along an existing route following the river.

That would adhere to long-held use patterns on the land, where private owners have allowed the public to hike, bike or Nordic ski. The biodiverse area straddling the river and the wooded hillside, referred to by Marble history museum curator Alex Menard as the Trail With No Name, has been the site of nature walks hosted by the Roaring Fork Conservancy to observe the beaver dams dotting the wetlands. A portion of it near the slag heap is also marked by giant slabs of marble — probably left over from a railroad that used to run through the site to a marble quarry on Treasure Mountain — that a previous owner artistically stacked just off the trail. The trail itself leads to scenic waterfalls on Yule Creek, although the falls are just over the property line on an adjacent parcel controlled by a separate owner.

“This is really a wildlife refuge,” said Menard, who was instrumental in bringing the project to the attention of the CVEPA. “It’s a place where you can see an eagle taking a trout out of water with its talons, then half a mile farther up, there is a moose; walk a little more, there’s a bear, a blue heron. It’s a wild place.”

As noted by Armstrong, it could also be a desirable spot for a “McMansion,” if not for the benevolence of the private donor — an out-of-state woman who also donated the land in town that is becoming Marble Children’s Park. That land is now owned by Aspen Valley Land Trust, which is working with the town and obtaining additional grant funding to spruce up the site.

AVLT is critical to the conservation effort on the wetlands parcel, as well. AVLT staff is completing survey and title work on the property and will soon be proposing action to the land trust’s board. However, the exact shape of that action is still to be determined, according to AVLT director Suzanne Stephens.

“(We) have talked with our lands committee about potentially accepting fee ownership, but we are also investigating potential partnerships and other options for the property, so it’s not a foregone conclusion that we’ll end up with it,” Stephens wrote in an email. “However, we are committed to seeing it protected one way or another.”

Potential partners include Colorado Parks and Wildlife, CVEPA, Pitkin County and other entities, Stephens said.

The site is “unquestionably one of the most important wetlands and riparian parcels in the valley,” Stephens said.

“The fact that it adjoins Beaver Lake and almost the entirety of its acreage is wetland and river make it extremely important from a land and water conservation perspective,” she wrote, referring to the body of water located on a CPW-owned parcel to the north. “The habitat is crucial and threatened across the west, and combined with the proximity to the town of Marble and the fact that the smelter site has historic significance and the parcel offers flat, easy access and a lovely walk make it a rare gem that deserves to be conserved for a multitude of reasons.”

‘Like a glass blob’

In the early days of industrialization and European settlement in the Crystal River Valley, a smelting and ore-crushing operation known as the Hoffman Smelter was erected on the site, according to Menard’s historical accounting. The site processed silver, lead, zinc and copper ore hauled by mule train from mines around Marble from roughly 1898 until 1911.

The smelter is long gone, but its shadow still hangs over the site. According to Armstrong, initial donation efforts in 2016 and 2017 ran aground on concerns about the slag heap, although proponents have long held that such concerns would ultimately be inconsequential.

The heap in question — perhaps 50 feet long and 10 feet high and located near the edge of the trail — “looks like something volcanic,” Armstrong said.

The mostly solid mound is, however, shedding pieces the size of small rocks. But there is not a strong presence of dust or other material that could wash away in a rainstorm or become airborne in dry conditions. CVEPA’s hope has been that any toxic material is inert, locked up in the rock.

“I have a strong feeling that it shouldn’t be something that should preclude something from acquisition,” Armstrong said in December, when CVEPA was awaiting the results of a materials analysis involving a private lab and CDPHE.

CDPHE — which was reviewing the site following a grant process where projects are submitted that present a public benefit — has substantially completed its analysis, and its findings line up with Armstrong’s characterization.

“Nothing is alarming,” said Mark Rudolph, an environmental protection analyst and brownfield site coordinator with CDPHE. He referred to the slag material as “like a glass blob.”

Rudolph noted that vegetation around the slag pile is healthy and that water quality in the Crystal River, about 50 yards from the material, meets the highest standards. Lead concentrations in the material fall in the range deemed acceptable for recreation sites, he said, and most of it appears locked up in the rocklike formation.

A final report from CDPHE is pending and will include recommendations on how to manage the site for public use. Those recommendations are likely to include clearing from the road any particles that have come off the slag heap. The road was recently built using a historic easement that allows access to a neighboring property owner, who is developing a home. Other strategies could include reseeding areas around the heap and using crushed marble or some other material to cover the slag particles that are visible on the shoulder of the road.

“It’s going to be a great addition to the town if we can get it all the way through,” Menard said of the conservation effort.

For Armstong and CVEPA, there is further work to be done to ensure public access to the falls, which are about 1.5 miles in from the beginning of the walk through the wetlands. The falls are on the property owned by the man who recently built the road. He could not be reached for comment.

“The owner of the private property seems amenable to allowing access, as he has placed ‘no trespassing’ signs farther up the road beyond the access to the falls,” the CVEPA wrote in a winter 2020 newsletter article about the Marble wetlands donation initiative.

This story ran in the May 29 edition of The Aspen Times.