RESEARCH: Assessment of Nonpoint Source Pollution from Inactive Mines Using a Watershed-Based Approach

Area of Science:

• Environmental Science
• Water Resource Management
• Geochemistry

Background:

• Inactive and abandoned metal mines pose significant nonpoint source pollution risks to water quality.
• Screening-level assessments are crucial for identifying and prioritizing areas for remediation.
• Existing methodologies often require extensive data, limiting their application in data-scarce regions.

Purpose of the Study:

• To develop and illustrate a watershed-based approach for screening-level assessment of nonpoint source pollution from inactive metal mines.
• To enable targeting of impaired waterbodies and critical source areas using limited stream discharge and chemical data.
• To provide a cost-effective framework for water quality assessment and remediation planning.

Main Methods:

• A framework was developed involving data evaluation, goal definition, data collection/analysis, and information reporting.
• Synoptic surveys with limited stream discharge and chemical data were utilized.
• The methodology was applied to the Cement Creek Basin in Colorado, USA.

Main Results:

• The approach generated information on water quality impairment, stream concentrations and loadings, and risks of exceeding targets.
• Preliminary targeting of locations for detailed investigation and remediation was achieved for Cement Creek.
• The methodology proved successful in cost-effectively generating actionable information.

Conclusions:

• The developed watershed-based approach is effective for screening-level assessment of nonpoint source pollution from inactive mines.
• The methodology facilitates targeted identification of areas requiring detailed investigation and remediation.
• This approach offers a practical and cost-efficient solution for managing water quality impacts from legacy mine sites.