By Jason Willis

Abandoned mines pose a serious threat to headwater streams in the West, because they seep toxic heavy metals such as zinc, lead and copper into streams and watersheds, undermining water quality and poisoning aquatic life. Trout Unlimited's Abandoned Mine Land program works across the West on projects to clean up abandoned mine sites and restore watershed health.

Difficult, remote, unpredictable, jarring—four adjectives that come to mind when I think about the Santiago Mine and Mill, perched at roughly 12,110 feet near Argentine Pass and the Continental Divide. The abandoned mine site sits in the headwaters of Leavenworth Creek, which ultimately flows into South Clear Creek, a drinking water source for the town of Georgetown. Trout Unlimited and USFS had been working together in the watershed since 2014 on various abandoned mine land (AML) reclamation projects when the idea for cleanup at the Santiago was conceptualized. With the site being listed on the state’s historical register, and eligible for the national register, proposed cleanup posed a unique challenge: How to mitigate high levels of lead, arsenic, and iron while simultaneously preserving the buildings as important relics of Colorado’s mining history?