Though South Africa is by far the largest producer of gold, its output has fallen by an average of 4 percent each year for 30 years. In 1970, a thousand tons were mined. In 2004, only 342 tons were extracted.
While mining companies are forced to dig deeper for gold, questions persist about the safety and technological challenges of ultra-deep mining.
For example, some scientists believe that deep mining may set off tremors in the Earth.
Transporting miners and rocks up and down such a long shaft also isn't easy: There is currently no rope or cable that could support its own weight at such lengths. And because temperatures are so high at the ultra-deep level, mine operators must come up with new ways to keep their miners cool.
And mine companies' quest for greater profit raises the fear that they are willing to risk the lives of their miners.
Several accidents in recent weeks have drawn attention to safety standards of the mining industry.
Earlier this month, a power failure at Harmony Gold's Elandsrand gold mine trapped 3,200 miners underground for more than 24 hours.
Mining took 199 lives in 2006, and so far in 2007, 150 people have died.
Mining has also become intertwined with race issues, as the majority of miners are black.
South Africa's National Union of Mineworkers is planning a one-day industry-wide strike in the coming weeks to protest mine conditions.
President Thabo Mbeki has ordered an audit of all the country's mines to figure out what's going wrong.
Some propose ultra-deep mining could be done mechanically, with robots or by automation.
But unions oppose that idea because it could cost some South Africans their jobs.
"We would not generally oppose the idea of ultra-deep mining if our people were safe, but we are opposing it on the basis that ... we have already seen a significant rise of fatalities," said National Union of Mineworkers spokesperson Lesiba Sheshoka.
Many of these fatalities are occurring in mines that are not ultra-deep, he added.
"[This] is sufficient evidence of negligence on the part of mine owners," he said.
Despite regular accidents, many companies, such as Gold Fields Ltd and AngloGold Ashanti, insist that safety is their main concern.
Some mining companies have set a goal of zero mining deaths by 2013—but even they acknowledge it's no guarantee.
"We have to concede that our safety performance in the last year and a half or so has been quite a lot less than satisfactory," said AngloGold Ashanti spokesperson Alan Fine.
Deaths at AngloGold mines jumped to 37 in 2006 from 25 in 2005, the Reuters news agency reported. During the first half of 2007, 18 AngloGold mineworkers have died, according to the agency.
Most recently, a miner's death on November 2 forced AngloGold to temporarily shut down its TauTona mine.
"We've got to fix our safety performance generally, but obviously ... ultra-deep level mining is risky," Fine said.
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