Gold mine in Tooele County would use cyanide to get metal
"The people who get in trouble with these heap leaches, they're like a big bath tub and at an elevation like Summitville, you can be constantly accumulating precipitation that you need to get rid of."
In Utah's arid west desert where the Kiewit Mine Project would be located, Havenstrite said the annual average precipitation is 11 inches.
"With these operations, you have to start with the worry about whether you are going to contaminate the waterways. Whatever groundwater is here is deep. We're not near a waterway — no mountain stream or pristine lake."
The mine's process pond will have an operating capacity of 100,000 gallons, but will be built to have enough additional capacity to withstand 100-year 48-hour precipitation events.
Its actual containment capacity would be 6.2 million gallons, which Havenstrite said emphasizes the prudence of "having huge safety factors. We want to make sure we never lose the (water) solution."
Herbert, too, said a lot has changed over the years. The division was just getting its groundwater rules finalized for the first time when the new Drum Mine operators came knocking for permits and could not meet the requirements to get up and running.
"We were just getting going with our rules," he said. "Since then, technology has improved dramatically for liner systems for protection in these type of facilities."
Payne said a Government Accountability audit was highly critical of lax regulatory oversight related to the use of cyanide heap leach pads in mining operations. The criticism helped propel tightening of mining rules about a dozen years ago. A subsequent Congressional inquiry in 2011 revealed that since the rules were put in play, there have been no high profile mine closures that have left government agencies stuck paying cleanup costs, Payne said.
"The regulators are a lot smarter about this," Payne said, "by forming a system they feel would prevent the creation of future Summitvilles and Gilt Edges. Those have been the rallying cries."