The Department of Defence has been questioned over why a nuclear waste management facility could not be established inside the Woomera Prohibited Area (WPA), which is twice the size of Tasmania.
Napandee, Kimba was designated as the preferred site for the federal government's National Radioactive Waste Management Facility (NRWMF) earlier this year.
The Senate Committee overseeing the government's recommendation met on Tuesday, with Australia's Nuclear Science and Technology Organisation (ANSTO), the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) and the Defence Department attending.
Centre Alliance Senator Rex Patrick had previously submitted an amendment to the legislation stating that the NRWMF site should be somewhere within the WPA selected by Resources Minister Keith Pitt after consultation.
The Defence Department had previously evaluated a number of sites, including Cultana, Joint Defense Facility Nurrungar (15km south of Woomera), as well as two sites both within the prohibited area, for the potential of hosting a NRWMF.
However their conclusion was the none of the sites were suitable for the facility.
First Assistant Secretary - Infrastructure Chris Birrer, a Defence representative who appeared at the inquiry, said the two sites inside the WPA were within the 'red zone' that is used for testing of Defence capabilities.
"Establishing the facility inside the WPA could effectively quarantine large areas of land from Defence use, adversely affecting the testing of advanced capabilities and weapon systems," he said.
"The military airfield is in regular use by manned and unmanned aircraft that, when required, carry weapons. With the introduction of new capabilities, the use of the WPA for testing will increase in the coming years."
During the inquiry Senator Patrick used a map of the WPA with the state of Tasmania overlaid on top to demonstrate the sheer size of the site, which is over 120,000 square kilometres.
For contrast, the size of Tasmania is around 64,000 square kilometres and the size of the NRWMF is estimated to be approximately 100 hectares.
"Defence mentioned that they have fuel and explosives stored at the airfield, and apparently that's OK to have there but they can't have a site that stores low level radioactive waste," Senator Patrick said.
"We have to be responsible and dispose of our own waste...if this facility is going to be in South Australia, it's much better to have it inside a remote, secured desert site."