Projects

Elkhorn Creek, Mine and Mill

In the spring of 2020, BHWC was awarded funds from the DNRC’s Reclamation and Development Grants Program and DEQ’s 319 Volunteer Monitoring Lab Analysis Program to investigate legacy impacts from historic, underground hard-rock mining in and around the Elkhorn Mine and Mill (Coolidge Ghost Town) on the Beaverhead Deerlodge National Forest.

Background

Mining for gold, silver, copper, lead, and zinc occured in the Elkhorn area from 1872-1965. Silver comprised the bulk of the metals extracted. The mining camp of Coolidge was formed in 1914, and the Elkhorn Mill was operational from 1922-1950. The Boston-Montana Development Company spent an estimated $5,000,000 on the Elkhorn project, which employed 250 men at its peak. The project ultimately failed because of the inability of the mine to meet the capacity of the processing facilities and the high cost of transportation, power, and processing due to the area’s remote location. Total production for the entire district from 1902-1965 amounted to: 53,373 tons of ore, containing: 1,184 ounces of gold; 208,593 ounces of silver; 383,580 pounds of copper; 857,679 pounds of lead; and 4,800 lbs of zinc. (Source: Montana DEQ).

The Problem

The historic Elkhorn Mine caused significant, ongoing impacts to water quality and aquatic life in Elkhorn Creek and downstream, the Wise River. The mining resulted in the export of thousands of tons of sediment and heavy metals to downstream reaches of Elkhorn Creek, Wise River, and the Big Hole River. While heavy metal concentrations have decreased dramatically since mining activity ceased (and some reclamation and remediation occurred in the early 2000s), Elkhorn Creek still exceeds heavy metals standards for aquatic life and provides poor quality habitat for native Westslope Cutthroat trout and Arctic grayling. The largest environmental concern in the area is an active flowing adit (horizontal mine shaft) that discharges an estimated 150 gallons-per-minute of orange-ish brown, metal-laden waters into Elkhorn Creek. There are also old waste dumps with seeps that flow into the creek. While past restoration activities made some improvement to these environmental hazards, the site requires further restoration.

The Solution

2020 – Site Characterization and Investigation (complete): During summer 2020, BHWC hired Watershed Consulting to monitor the site to gain a better understanding of the degree and extent of water quality exceedances and heavy metal contamination in Elkhorn Creek and the vicinity of the mine and mill. The goal of the site characterization was to investigate the extent to the ongoing contamination and ways in which to stop and/or slow this toxic water from entering Elkhorn Creek. An aerial topographic (LiDAR) survey was also flown summer 2020. The LiDAR data is another major component to this project. Both the site characterization and the LiDAR survey will be used to inform future restoration decisions.

2021 and beyond – RESTORATION! A larger restoration approach for this area is currently under development.