Johannesburg — HARMONY Gold's claim last week that booby trap devices, apparently laid by illegal miners, had been found at one of its Free State mines returned the spotlight to a problem that the company has spent the past 12 months trying to eliminate.

A year has passed since a disaster at Harmony's disused Eland shaft, near Welkom, killed at least 84 men who had been illicitly looking for gold.

That prompted an illegal-mining crackdown co-ordinated by Mineral Resources Minister Susan Shabangu, who set up a stakeholder forum including representatives of the Department of Mineral Resources, mining companies and trade unions.

They have met regularly to discuss tactics to counter illegal gold mining, an industry worth R5bn in 2008 according to the Chamber of Mines.

But with the gold price near record highs, there are still plenty of young men prepared to risk their lives, spending months at a time underground in the hope of receiving a cash windfall from their syndicate bosses.

At the municipal-owned G Hostel in the township of Thabong - the notorious hub of Welkom's criminal mining industry - the young, male residents are cagey about admitting involvement in the practice. But local residents insist there has been little reduction in the activity of the so-called "zama-zamas" ("let's have a go" in Zulu).

While some locals despise the largely foreign criminals for looting SA 's resources, others say they benefit the area. "They don't make any trouble when they come out of the mines," says Helson Mthiyane, a community organiser and former miner. "People love them because they make a lot of money, and they spend it in the community."

But over at Harmony's Masimong mine, human resources manager Garth Boersma has no doubt of the damage the zama-zamas have inflicted on the company's operations.

Harmony is particularly vulnerable because its Free State shafts form a vast, interconnected warren that allows illegal miners to operate undetected for months. It is by no means the only company to have encountered the problem, however: Pan African Resources had extensive problems last year at its Barberton operations in Mpumalanga which significantly reduced its gold production.

Apart from the fact that their removal of material amounts to theft, the criminal miners endanger their legitimate counterparts through unsafe mining activities, increasing the risk of accidents.

But it is Harmony miners who have been enabling the zama- zamas to access the shafts, says Mr Boersma. The criminals use a combination of bribery and intimidation to persuade workers to smuggle them into the mines at the beginning of a shift. The legitimate miners then provide them with provisions at extortionate prices.

The latter phenomenon was relatively simple to tackle, says Mr Boersma: Harmony now tightly restricts the provisions taken underground by its workers, in a bid to starve out the illegal miners.

But to stop them gaining access in the first place, the company was forced to introduce a complex system of biometric gates that read the shape of workers' fingers, meaning those not registered cannot get through. The technology has drastically reduced the prevalence of illegal mining, Mr Boersma says. But it has so far been introduced at only four of Harmony's Free State projects, meaning that the others are potentially vulnerable.

Once underground, they will be able to access any part of the shaft network, admits Harmony's chief operating officer in the Free State, Tom Smith.

"You can walk 35km if you want to," he says, and many of the gangs have recruited former Harmony workers who are familiar enough with the network to know exactly where to go.

But Mr Smith is adamant that a huge ramp-up in security spending, costing almost R100m in the past year, is steadily cutting off the zama-zamas.

It's an optimism shared by Jan Nelson, CEO of Pan African Resources , who says the situation at Barberton has steadily improved since a chaotic period last year.

"It's mountain land, so there are openings all over the place ... We try to seal them off, but we have to keep some open for ventilation," he says.

The illegal miners at Barberton were audacious enough to take Pan African employees hostage in November and December last year, forcing a two-week suspension of operations. The company responded by increasing security spend to nearly R4m a month, appointing a security executive reporting directly to the CEO, and offering rewards of up to R50000 for information.

About 500 have been arrested, says Mr Nelson, and illegal mining is no longer interfering seriously with the Barberton mines.

Paul Mardon, head of health and safety at the Solidarity trade union, commends the leadership shown by Ms Shabangu in coordinating the increased focus on illegal mining.

The stiffer sentences for culprits have helped, Mr Mardon says. "Illegal miners endanger the lives of workers, as well as their jobs," he says. "But I'm not just saying this is a bunch of hard- nosed criminals - we realise the economic pressures on them. They are as much victims of this as anyone."