It was only a few years before her husband Gerald was diagnosed with lymphatic leukemia.

"It was about '64 or '65, we saw them with their instruments," Mrs Conlan recalled. "They came up later and told us what they were doing but said there was nothing to worry about."

But in fact there was plenty to worry about.

"We got letters from the Health Commission saying we had (radioactive) radon gas," she recalled.

It took 10 years before doctors from the State Government Health Commission arrived at their home and tested the Conlan family, which by then included two daughters.

"The doctor said you have high levels of radiation on your property. But they said there was nothing to worry about and told us not to say anything, they didn't want it in the papers," she said.

Little wonder. Mrs Conlan's family home was named Radium. It was sitting atop a site where thousands of tonnes of radioactive waste - including processed uranium tailings, thorium and radium - were buried from the processing plant that once operated there between 1911 and 1916.

Mrs Conlan's house has since been demolished, declared unsafe and her husband has since died.

It took 15 years for Mr Conlon, who was first diagnosed at the young age of 54, to succumb to the disease.

Where the Conlans' home once stood is now a vacant block of land that this week The Daily Telegraph revealed was a secret radioactive waste dump known to State Government authorities since the 1960s.

The Health Department, which took control of the site, now wants to sell it so a new home can be built in its place. They propose to dig up the waste and truck it to a landfill site in western Sydney.

But the neighbours are demanding answers before anyone touches it - answers that Mrs Conlan never got when she and her husband first moved there in 1956.

"We were told there used to be a factory there. But we had no idea what they had been doing there," Mrs Conlan said.

In 1972 Mr Conlan was diagnosed with leukemia, a blood cancer that is often linked to exposure to radiation.

Five years later the State Government offered the Conlans $70,000 for their home. They settled for $75,000 - they had little choice - but it was nowhere near enough to buy back into the area so they moved to Ryde.

Waste from neighbouring properties was dumped on number 9 before it was covered with dirt. It has remained in that state ever since.