T
he area southwest of Tucson has been known as a rich mineral area since the late 1800, but in the early days, the miners followed an ore body by tunneling and chipping it out. It had to be smelted. In the early 1970’s, the “hardrock” mining started. They dig up the bedrock and process it, even if it has only 1% of copper. This requires the separating out of the copper (and other desirable minerals) with chemical reagents. The resulting slurry is put in tailing impoundments. The groundwater table has been dropping some 2-3 ft. per year from the combined affects of pumping for mineral processing. In U.S. the states are responsible for their own water laws, even on Federal lands. When the Arizona legislature wrote the “Groundwater Code” in 1980, they “grandfathered” (ie. honored the status quo) all agricultural groundwater pumping and exempt mining companies from any water depletion rules, although the deficit at that time was 2.5 million acre feet per year. They accomplished this stupidity because they were getting Federal money and loans to pipe Colorado River water to Phoenix and Tucson. The water usage by the mines is causing cones of depression all over Arizona. The pollution of the groundwater is extensive near the tailing impoundments since they were built before laws that impoundments had to be lined. The biggest problem is that there is uranium scattered throughout bedrock in the Southwest, so when inert uranium is loosened from its native place, ground to power, and dissolved in chemical solutions, it starts decomposing into its many components, such as Gross Alpha and Radon, which are more harmful to human health. Even though the toxic plume had entered the drinking water of the small, retirement town of Green Valley in 2000, nothing was being done because the main contaminant was sulfate compounds, not a carcinogenic. However, the extremely hard water was ruining electric appliances, hot water heaters and the whole town was buying bottled water from cooking and drinking. Nancy Freeman determined to do something about the problem and she copied all the records from Department of Environmental Quality records and compiled the data into logical, readable tables. Then she posted them to a website and had weekly meetings at the local library telling people what was going on. Also the Arizona Attorney General’s office became involved and found an old statue that prohibited any pollution to public drinking water. Then the mining company did sign a contract that they would do something. In 2007, they spent 12 million dollars providing the water company two wells outside the toxic plume. Then they have spent two years studying the plume, making reports, and deciding the best procedure for actually cleaning the plume. Today that plan is complete, and is going to Dept. of Environmental Quality for approval. This plan includes a new lined tailing impoundment away from the town. The old impoundment will be closed and water wells will be sunk in the middle of the plume. The contaminated water from those wells will go directly to the mining operations to be used there. So the twice-contaminated water will go to the new lined tailing impoundment.