Dams of Tailings Ponds

Are they safe?

Erosion is visible externally on the dams, but what about below the ground?

EPA Statement:

"Leakage from tailings impoundments can also be a serious ongoing environmental problem. Leakage can transport contaminants to ground or surface water. Uncontrolled leakage can threaten the integrity of the impoundment structure itself, which can lead to the possibility of catastrophic dam/embankment failure. Catastrophic embankment failure can adversely impact downstream wild life . . . and humans.

What about safety regulations for tailings dams in Arizona?

Arizona Department of Water Resources (ADWR) Regulates Dams

The Flood Warning and Dam Safety Section of the Arizona Department of Water Resources regulates all dams in the state except mine tailing dams and federal dams. ADWR regulates 212 dams in Arizona. Dams not under ADWR jurisdiction include approximately 65 federal dams, 34 copper tailing dams and 110 tribal dams.

ADWR and Mine Tailing Dams

Until the Arizona Legislature decided otherwise, Arizona Department of Water Resources understood state law to include mine tailing dams under its jurisdiction. The agency deemed its regulatory oversight to be appropriate since, if a mine tailing dam failed, the consequences would be the same as any dam failure. Life and property would be endangered.

"The mining industry, however, questioned ADWR's oversight of tailing dams. To settle the matter ADWR asked the 1977 Arizona Legislature to change the wording of the law to clarify that ADWR did, in fact, regulate mine tailing dams. The Legislature took the opposite tack. It specifically excluded mine tailing dams from ADWR jurisdiction."*

Information quoted from https://ag.arizona.edu/AZWATER/arroyo/092dams.html

Three years later in the Phelps Dodge copper operations in Tyrone, New Mexico, there was a major failure of a tailings pond dam. When the dam ruptured, there was such a flood of water that power lines were knocked over, water mains were broken. "Fortunately, a series of check dams along the dry streambed contained the mess, and there were no personal injuries." Are there check dams in place between Green Valley and the dam?

*Note: This was after midnight sessions when the lobbyists for the mining companies finally wore down the legislators—from an eyewitness report.

Why did the mining corporations want to avoid safety inspections? What do you think?

Dam failures occur all over the world, but this was a particularly fateful one--again in New Mexico.

The High Cost of Uranium in Navajoland

The biggest expulsion of radioactive material in the United States occurred July 16, 1979, at 5 a.m. on the Navajo Nation, less than 12 hours after President Carter had proposed plans to use more nuclear power and fossil fuels. On that morning, more than 1,100 tons of uranium mining wastes -- tailings -- gushed through a packed-mud dam near Church Rock, N.M. With the tailings, 100 million gallons of radioactive water gushed through the dam before the crack was repaired.
        By 8 a.m., radioactivity was monitored in Gallup, N.M., nearly 50 miles away. The contaminated river, the Rio Puerco, showed 7,000 times the allowable standard of radioactivity for drinking water below the broken dam shortly after the breach was repaired, according to the Nuclear Regulatory Commission. The few newspaper stories about the spill outside of the immediate area noted that the area was "sparsely populated" and that the spill "poses no immediate health hazard."

Click here for everything about tailings dams from the EPA files.

copy and paste this link if it doesn't come through: https://www.epa.gov/epaoswer/other/mining/techdocs/tailings.pdf


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