November 6, 2007—The Gold Fields Ltd. company is set to break the mining depth record as it drills down 2.5 miles (4 kilometers) at its Driefontein location, about 37 miles (60 kilometers) southwest of Johannesburg, South Africa.

An estimated 8.5 million ounces (240 million grams) of gold is thought to lie in the mine at such depths.

As gold prices reach near-record highs, South Africa's mining companies are rushing to take up a new, more dangerous form of mining: "ultra deep."

But several accidents in South Africa—the world's largest gold producer—in recent weeks have drawn attention to the safety record of the mining industry, experts say.

"We would not generally oppose the idea of ultra-deep mining if our people were safe," said Lesiba Sheshoka, spokesperson for South Africa's National Union of Mineworkers.

"But we are opposing it on the basis that  we have already seen a significant rise of fatalities."

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