Friday, March 25, 2011

Uranium's Legacy in Southeastern Utah

The U.S.’ first commercially operated uranium mill was built on the bank of the Colorado River near Moab, Utah, by Charlie Steen’s Uranium Reduction Company in 1956, and expanded by Atlas Minerals Corporation beginning in 1961. This facility extracted yellowcake uranium for nuclear bombs and reactors from ores trucked from over 300 mines on the Colorado Plateau. The slime-like wastes from the mill, laced with radium, uranium, thorium, polonium, ammonia, molybdenum, selenium and nitrates, were slurried into an unlined pond in the floodplain of the river. As more capacity was needed, contaminated soils were bulldozed up to raise the sides of the tailings impoundment. By 1984, when the mill was put on standby, this pile of mill wastes had grown to 16 million tons, covering 130 acres to a depth of 110 feet.

The Atlas site is the fifth largest uranium tailings pile in the U.S. and by far the most dangerously polluting. Located in a deep, narrow valley with the town of Moab, irritating dust and heavier-than-air radon gas often blanketed the community in the days of mill operations, until Atlas was required to spray a synthetic binder over the tailings in the late 1980s. From the unlined bottom of the pile, toxic seepage has turned the groundwater into a radioactive broth of heavy metals and ammonia that bubbles up in the Colorado River just a few hundred feet away. The nearshore water in the river is so poisoned with ammonia that it is immediately lethal to any fish unlucky enough to swim there.

Today’s discharge of contaminated groundwater into the river is estimated at 110,000 gallons/day. In wet years, when the spring flood in the Colorado River exceeds about 45,000 cfs, the river tops its banks and inundates the base of the tailings pile, leaving it not merely leaking into, but standing in the drinking water for 25 million downstream users in Nevada, Arizona, California, and Mexico. This level of flood was observed in 23 different years during the last century, most recently in 1993.

The Utah Mill Project

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