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Monitoring and Evaluating Reclamation Outcomes: A Case Study of the Roy Pray Mine. By: Ashley Bembenek Environmental Consultant. Image retrieved from Google Earth. Roy Pray Mine Near Lake City, Colorado. Denver. Grand Junction. Lake City. Historic Mining near Lake City.
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Monitoring and Evaluating Reclamation Outcomes: A Case Study of the Roy Pray Mine By: Ashley Bembenek Environmental Consultant Image retrieved from Google Earth
Roy Pray Mine Near Lake City, Colorado Denver Grand Junction Lake City
Historic Mining near Lake City Historic Mining near Lake City - Gold and silver - From the 1870s to 1920s Palmetto Gulch - Heavily impacted area - 303(d) listed in 2002 for Cd, Cu and Zn - Led to additional data collection and TMDL From Kansas State Historical Society Image retrieved from Google Earth
Roy Pray Mine Reclamation Project 2003: Bulkhead sealed at Roy Pray Adit 2005: Adit waste pile relocated and re-graded
Roy Pray Mine Reclamation Project Objectives Bulkhead sealed to reduce flow from the mine adit Tailings pile removed from direct contact with stream and re-graded to reduce erosion potential
Post-Reclamation Water Quality Monitoring Objectives Have reclamation activities at the Roy Pray Mine reduced metal concentrations in surface water samples? How has flow from the adit and adjacent pre-existing seeps changed following reclamation activities?
Roy Pray WQ Monitoring Areas Below: Palmetto Gulch Above Roy Pray Below Roy Pray Roy Pray Mine
Roy Pray WQ Monitoring Areas Above Roy Pray Roy Pray Mine Below Roy Pray Below: Palmetto Gulch
Cadmium Concentrations: 1999-2010 Cadmium in µg/L Cd concentrations above the Roy Pray & in Palmetto Gulch have remained relatively stable through time Initially, Cd concentrations declined at the Roy Pray Mine & immediately below the mine More recently, Cd concentrations have increased
Copper Concentrations: 1999-2010 Cu concentrations in Palmetto Gulchhave remained stable Elsewhere, Cu concentrations have increased over time Copper in µg/L Increases above & at the mine adit do NOT account for all of increases measuredbelow the mine Groundwater seeps interact with mine pool water or other low quality water--- Cu concentrations are very high 2010 data from below the Roy Pray has the highest Cu concentrations measured to date
Zinc Concentrations: 1999-2010 Zn concentrations above Roy Pray & in Palmetto Gulch have remained stable Zinc in µg/L Zn concentrations initially declined at the Roy Pray Mine Since 2005, Zn concentrations have risen at the mine and immediately below it
Metal concentrations on the rise, what has flow done? Flow from the mine adit is similar to pre-reclamation levels Flow from below Roy Pray Mine has likely increased over pre-reclamation levels Currently, metal loads are lower than pre-reclamation metal loads However, there is little evidence to suggest chemical or hydrologic stability at this location Additional data is needed to better understand current conditions
Responsive Management Project data translated into information to direct further management actions Project partners have agreed to collect more water quality samples and additional data Additional reclamation strategies will be developed, as needed Conditions at the Roy Pray Mine highlight the need for post-reclamation monitoring and evaluation
Questions or Comments… Additional questions: Ashley Bembenek abembenek@yahoo.com Image retrieved from Google Earth Image retrieved from Google Earth