Abandoned Mine Land Impacts on Tributaries in the Upper Yakima River Watershed, Eastern Cascades, Washington

Effluent from abandoned mine lands (AMLs) in several drainages in Washington’s Eastern Cascades flows into the Yakima River. Similar sites in Idaho and Colorado are known producers of heavy metals and acid mine drainage. I determined the effects of nine AMLs on water quality in four tributaries to the Yakima River. Archival work was conducted to determine sites that were mined and contained a mill. Each site was characterized by physical features. Water and sediment samples were collected above, at, and below each AML. Samples were analyzed for pH and heavy metal content, and evaluated to determine if the AMLs are sources of pollution as defined by EPA drinking water standards. Results show that mill sites in the Cle Elum and Teanaway River drainages are contributing small amounts of heavy metals to their surrounding environment. Analysis using modified USGS mine waste characterization techniques also shows that these sites are among the most likely to contribute these pollutants to fluvial systems. Additionally, due to local geologic influences, arsenic and lead in water samples were elevated above EPA standards throughout the study area, and the effects of acid mine drainage make these metals more bioavailable. These AMLs contribute to low discharge systems and the effluents from these sites will disproportionally impact them compared to larger downstream systems; however, it the effect they will have on either is likely limited. These results may be extrapolated to other, similar small-scale, historical mineral processing sites in the region, indicating that they pose less environmental hazard than larger sites.

Name thesis:degree_name

Master of Science (MS)

Discipline thesis:degree_discipline

Cultural and Environmental Resource Management

Year dc:date.available

2018

Author dc:creator

• Kugel, Scott

Contributors dc:contributor

• Karl D. Lillquist
• Carey Gazis
• Clay Arango

• Geochemistry
• Mines
• Geomorphology
• Environmental Indicators and Impact Assessment
• Environmental Monitoring
• Natural Resources Management and Policy
• Water Resource Management

Language dc:language

English

Repository record dc:identifier

https://digitalcommons.cwu.edu/etd/939

OAI identifier oai:identifier

oai:digitalcommons.cwu.edu:etd-1972