The ban comes in the wake of the deadly cyanide spill in Romania in late January that was considered to be the world s worst ecological disaster since the Chernobyl nuclear meltdown. In that spill, 3.5 million cubic feet of mine waste contaminated with cyanide and heavy metals was released into a tributary of the Danube River from a gold mine operated by Australia s Esmeralda Exploration. That disaster killed all aquatic life in a 250-mile stretch of the Danube. Cyanide heap leach technology is the standard technology of the gold mining industry. It involves the spraying of cyanide-laced solution over ore heaps.
Cyanide acts as an agent to separate the rock from gold.
There are dozens of active gold mines in the U.S. that use the cyanide heap leach process. There are hundreds more abandoned mines in the U.S. that used the process and continue to emit high levels of pollution. The problem prompted the citizens of Montana to pass an initiative banning the process at new mines. Citizens in several other states including Colorado and Wisconsin are considering such initiatives. Internationally, citizen opposition has blocked this mining technique in the Pergamon region of Turkey.