They once pulled a power cable under Lake Burley Griffin. On another job they guided a directional drill on an underground curve to follow Brisbane Avenue in Barton to bring new services into the Kingston Foreshore.

They settled a $10 million dispute last year with mining billionaire Andrew 'Twiggy' Forrest's subsidiary Chichester Metals after a four-year legal battle and are now targeting Sydney's infrastructure boom.

Twenty years ago in the dying days of Woodlawn Mine, Keith Whittaker and Andrew Rowlands, both sons of farmers in the Goulburn district, agreed to find a better way of earning a living.

Mr Whittaker did his apprenticeship as a diesel mechanic at the mine, and later started his own business hiring staff for the mine. Mr Rowlands, a fitter machinist who had previously helped build racing cars, specialised in providing mining equipment.

Accustomed to taking risks, the men wanted a fresh challenge.

"I'm not interested in the stuff everyone else can do, there's no fun in that, and there is no premium price in that," Mr Whittaker says.

When Damien Foley, then working for Telstra, rang Mr Whittaker, whom he had known since kindergarten and said, "Have you heard of a directional drill?" it was the novelty the mine mechanic was looking for.

He flew to London chasing his future wife, Karen, who was on holidays, and while there looked up an agent for a directional drill machine. On his return he and Mr Rowlands met Mr Whittaker's accountant in Goulburn, John Cousins, for advice before flying to Germany for a week's training on the drilling equipment.

Instead of digging a trench, the drill has a device in the drill head which can be tracked underground by its operator, and steered over a pre-determined course.

"It took my fancy, two guys having a go," Mr Cousins says. "They started off with an idea for un-tested equipment. They had no money and they had no clients," he said, unaware at that stage he would become their company's managing director and later fight one of Australia's biggest miners over a $10 million bill.

All that was ahead of them. For now Telstra and ActewAGL in Canberra became a solid launching pad for Underground Envirotech Australia, which later became UEA. "They were going hell-for-leather, they went from one drill, then two or three within a couple of years," Mr Cousins says.

Mr Whittaker says: "If you mix farming with mining you get a pretty crazy sort of person because you just get things done. If there's not an answer, it just means we haven't thought hard enough about it."

The two men's skills complemented one another.

"I don't have an office, I don't know how to use a computer and have no intentions of using one," Mr Whittaker says.

Mr Rowlands, who handled the paperwork, said their early contracts included a 1.2 kilometre sewer rising main linking the new Kingston Foreshore development with an existing sewer under Brisbane Avenue.

"It had to have the backing of ActewAGL because it was the first time a pressure sewer pipe had been put in using polyethylene," he says. "It was highly technical, an on-grade job, usually done with micro-tunnelling."

Such projects rely on absolute accuracy to get the correct fall. Even on a straight tunnel this is difficult.

"Because the project had to be done on a curve following a road, directional drilling was the only way, steering around corners," Mr Rowlands says. When it was completed Engineers Australia, Canberra division, highly commended the project.

UEA flourished and expanded into Sydney. Telstra was their biggest client. But work stopped abruptly when the Sydney Olympics arrived, to avoid cutting underground networks. When work resumed, the telco engaged bigger contractors, leaving the ex-miners without work.

"We had a lot of ex-Telstra guys who were cable joiners, our drilling business was something like 70 or 80 per cent of our work, all coming out of Telstra," Mr Rowlands says. "It was a big lesson in business for us. We kind of knew it was wrong to have that much reliance on one customer, but we had assurances from Telstra it would all pick up and get going again. But it never did."

They focused on Sydney and Canberra's water and power markets, their directional drill smashing old earthenware pipes and pulling replacement poly piping behind them.

Drilling through solid rock, tidal sand and under the ocean the business spread into the electrical market, and other civil and mining work.

"We faced bankruptcy at times, did some stupid things," Mr Whittaker says. "If you don't have a go, you never never know."

At the peak of the mining boom UEA employed 260 people and annually turned over $80 million. Along the way debates flared on whether to close after big capital outlays turned sour.

"We just hung in there for a bit longer and turned it around," Mr Cousins says.

In Western Australia's Pilbara region, UEA commissioned a $3 million surface mining machine which led to more work, and ultimately the need to invest in buying eight more machines at that site and three in the Kimberley region. At the end of the Pilbara contract the mine owner and UEA ended up in a legal dispute over money owed to UEA.

"It is not like things were done wrongly on site," Mr Cousins says. "It was all to do with proving what you were owed, and yes, there were clerical errors. So we are not 100 per cent blameless, but we are 98 per cent perfect, if you know what I mean.

Documents filed with the Western Australian Supreme Court indicate the dispute was with Chichester Metals, a subsidiary of mining billionaire Twiggy Forrest's Fortescue Metals. The matter was settled by consent in April last year. Under the terms Mr Cousins cannot disclose details.

"I was in charge in those days of the financial records, I was their external accountant, then chief financial officer, then chief executive officer, I was passionate because they [the mine owner] were challenging some of the numbers which I had full faith in.

"As I was ultimately responsible for the numbers, I looked upon this as a personal matter and while there was pressure placed on me to settle the dispute for a lower figure I was not prepared to do so."

The legal fight dragged on for more than two years, Mr Cousins dug in and UEA achieved a positive outcome.

Two months ago UEA moved out of Western Australia, and will step up on major projects in Sydney like the North West Rail Link, West Connex and North Connex.