Remediation of Abandoned Mine Lands

Thursday, October 2, 2008 : 3:40 p.m.

Integrated Engineering Alternatives for Mine Site Remediation at the Captain Jack NP: Site in Boulder County, Colorado

Christine Galli LaBerge, PE, M.B.A., Walsh Environmental Scientists and Engineers LLC and Rick Rudy, PG, Ecology & Environment Inc.

The Captain Jack (CJ) Superfund Site is located in Boulder County, Colorado, within the Left Hand Creek Watershed.  In the late 1800s through the early 1900s, several mining companies consolidated in the area known as the Big Five with a resulting mine complex/mill considered to be one of the largest gold and silver producers in Colorado.  The resulting mining activity left behind significant volumes of waste rock, tailings and several miles of open and collapsed underground tunnel workings.

 In the 1980s, the Environmental Protection Agency discovered fisheries and wetlands impacts in the Watershed.  These impacts were suspected to be associated with discharges of metal-contaminated water, and the CJ facility was identified as the primary source.

 Based on human health and ecological risk assessments, remedial action objectives were developed to protect from risks associated with highly acidic water and metals contaminants identified in mine waste and surface water.

 Remediation alternatives were developed with close community involvement and strict adhereance to Colorado and Boulder County historic structure preservation.  Several integrated alternatives, specifically focused on mine tailings and acid mine drainage remediation, were developed and evaluated in detail as follows:

- Off-Site Disposal of Principal Threat Waste (PTW) and Capping
-  On-Site Repository for PTW and Capping
-  On-Site Repository for Contaminated Soils
-  Bulkhead in Big Five Adit
-  In-situ mine pool neutralization with phased biochemical reactor
-  Precipitation Water Treatment System for Big Five Adit Drainage and;
-  Biochemical reactor treatment of Big Five Adit Drainage

Based on detailed engineering evaluations, a combination of repository and in-situ mine pool neutralization construction will likely be implemented in order to adequately address the site risks. 

Christine Galli LaBerge, PE, M.B.A., Walsh Environmental Scientists and Engineers LLC Ms. LaBerge has 9 years of experience as an environmental engineer and project manager. She has experience in engineering design, water, wastewater, hazardous materials, mining engineering, and sanitary engineering. She has worked directly with numerous federal clients including the DOD, USFS, EPA, BLM, GSA, NPS and AFCEE. As project manager, Ms. LaBerge provides oversight and technical support on projects involving abandoned mine lands, engineering design, feasibility studies, and hazardous materials management. She has worked on dozens of abandoned mine lands projects throughout the US and has managed high profile, large-scale design projects for several government agencies.

Rick Rudy, PG, Ecology & Environment Inc. Mr. Rudy has over 25 years of experience in the environmental consulting industry. He manages and oversees numerous large scale federal contracts including BLM/USFS Technical Advisory contract which manages numerous BLM abandoned mine land projects.


Remediation of Abandoned Mine Lands