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A Case Study. The Copper Basin Problem. What Do You Know About Copper?. List objects made of copper Where is copper found on Earth? How is copper refined? What are the environmental impacts of copper mining?
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A Case Study The Copper Basin Problem
What Do You Know About Copper? • List objects made of copper • Where is copper found on Earth? • How is copper refined? • What are the environmental impacts of copper mining? Watch the video From Ore to More to learn about copper production methods at Kennecott Utah Copper. http://www.kennecott.com/
Is There a Problem Here? Historic photo of deforestation in North Potato Creek Watershed in the Copper Basin See other historic photographs at http://www.epa.gov/region4/waste/copper/historicphotos.htm
A Biological Desert? The Copper Basin Mining District was called the largest man-made biological desert in the United States. • 50 square miles in size • Completely absent of vegetation • Extremely acidic stream water • Only one organism, an insect, was found in the water during an EPA survey in 1970.
Mining District Map • How many mines are in the district? • How many lakes are there? • How many streams? • How many watersheds? (observe the green lines) • How many towns? More maps http://www.glennsprings-copperbasinproject.com/maps.htm http://www.epa.gov/region4/waste/copper/sitemap.jpg
One of the 14 Mining Sites Copper Basin Mining District is located in Polk County, Tennessee and Fannin County, Georgia
A Disturbing Image • What do you observe? • What can you infer?
Mining Impacts • Mining and related processes produced solid wastes and byproduct materials that remain on site. • sulfide-rich ore • sulfide bearing waste rock • tailings • granular and pot slag • iron calcine • magnetite • iron concentrate • wastewater treatment sludge • demolition debris • Many of these materials are capable of, or are known to be, releasing acid or metals to the environment.
This Scene Doesn’t Look Polluted • What do you observe? • What can you infer? • What questions do you have? • What additional information would you want to know?
Mine Collapse • The previous image shows how water flowed into the Isabella Mine after it collapsed. http://www.epa.gov/region4/waste/copper/copphoto/isabell1.htm
Early Problems • By the early 1900s, the mining sites were deforested to provide fuel for the roasting of ore. • The ore roasters generated sulfur dioxide gas that killed any remaining vegetation. • Without the plants to protect the land, massive amounts of soil eroded filling two stream beds and reservoirs on the Ocoee River.
Later Problems • Mining and related activities resulted in contamination from metals http://www.epa.gov/region4/waste/copper/copphoto/pbccontam.htm • and polychlorinated biphenyls (PCBs). http://www.epa.gov/region4/waste/copper/copphoto/opentran.htm
Acid, Heavy Metals, Sediment • Davis Mill Creek and the Lower North Potato Creek contribute acid, heavy metals, and sediment to the Ocoee River. • The Davis Mill Creek watershed contains more than 15 million tons of mining-related waste materials and is devoid of aquatic life. http://www.epa.gov/region4/waste/copper/copphoto/polkmnd2.htm http://www.epa.gov/region4/waste/copper/copphoto/dcmpile.htm
Would You Pick-up This Leaf? Photograph of leaf taken from the streambed of Davis Mill Creek just upstream of the Calloway Mine. The leaf and the streambed in the background are coated with iron hydroxide that precipitated out of the water in response to changes in pH.
Polluted Davis Mill Creek • physical appearance has changed • large portions redirected due to mining operations • meanders around and through waste piles, picking up additional contamination as it flows toward the Ocoee River • contributes approximately one percent of the water in the Ocoee River • largest single source of acidity and heavy metals • pH of the creek water ranges from 2.5 to 3.5 • brightly colored iron precipitates coat the stream bed and quickly cover any organism or organic matter that enters the stream (look back at the photograph of the leaf)
Transition • Complete various laboratory activities to determine the effect of environmental pollution on organisms • Return to the PowerPoint to learn about potential solutions to the Copper Basin Problem
Addressing the Problem • Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), more commonly known as “Superfund” • EPA has the authority to pursue long-term remedial response actions that permanently and significantly reduce the dangers associated with releases or threats of releases of hazardous substances. • When using Superfund monies, these actions can be conducted at only those sites listed on EPA’s National Priorities List (NPL). • EPA investigated placing Copper Basin Mining District on the NPL. Although the site could have been addressed through listing on the NPL, an alternative solution was proposed: cleaning up the site through enforceable legal agreements.
Collaborative Effort The site is currently being investigated and cleaned up through a collaborative effort • EPA, the Tennessee Department of Environment and Conservation (TDEC), and Occidental Petroleum Corporation (OXY USA) • All signed a Memorandum of Understanding (MOU) and several related legal agreements on January 11, 2001 http://www.epa.gov/region4/waste/copper/mou_fnl.pdf
Surface Impoundment GSHI refurbished the Cantrell Flats Wastewater Treatment Plant to treat acid and metal laden waters of the creek, underground mine waters, and contaminated storm water.
Restoration Progress View historical and restoration images of the of the Copper Basin Mining District http://www.glennsprings-copperbasinproject.com/Gallery.htm Copper Basin High School students planting trees
Before… Tailings pond circa 1900
After http://www.glennsprings-copperbasinproject.com/briefings.htm Tailings pond in 2003 with good quality water.