"In 1999, Environmental Protection Agency in Washington, D. C. published a report on .... uranium and radioactive chemicals in the “Copper Belt” of Southern Arizona."

Excerpt:

"Levels in excess of the federal MCLs and state guidelines were found in groundwater and surface water samples, as well as soil and sediment samples at abandoned and active copper mines. TENORM exceedences were also found in groundwater at active and inactive copper mines. Uranium byproducts were recovered from heap leach dumps and in-situ operations that feed SX-EW and ion exchange circuits at several copper mines. Radioactivity was discovered in copper mineral processing waste streams. Elevated levels of radioactivity were also found to occur in the process solutions and process wastes."

For entire report, see: www.epa.gov/radiation/docs/tenorm/402-r-99-002.pdf  "

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