Geoscience Australia will not reveal the contents of a report it has commissioned on the future of its laboratories and the main workplace union saysthe labs' work could be farmed out to the private sector.

But the agency insisted this week that there is "no proposal to privatise any of Geoscience Australia's laboratory facilities."

Geoscienceemployees nearly 600 scientists, researchers and other public servants at its Symonston headquarters, a Canberra landmark which it has occupied for two decades.

The lab workers analyse rock, oil and natural gas samples supporting their Geoscience colleagues, as well as universities and the oil and natural gas industries.

But change is in the air with the "in-house" lab facilities nearing the end of their "design life" and the agency's bosses have called in the consultants to tell them what to do next.

That means more outsourcing and an uncertain future for many of the employees at Geoscience's HQ,the Community and Public Sector Union warns.

The agency has hired private sector outfit Keith Kenyon Consulting to compile a report on the future of the labs but refused to make consultants' findings public.

"This review identified future challenges as Geoscience Australia's in-house facilities reach the end of their design life," a spokeswoman said.

"The laboratories currently utilise various in-house and outsourced laboratory solutions and the review identified a wide range of options.

But the union says the lab workers have no idea what their future holds and that Geoscience management will not answer basic questions.

"The undecided future of Geoscience laboratories is a serious concern," CPSU Deputy Secretary Beth Vincent-Pietsch said,

"Outsourcing has not been ruled out but it absolutely should be," she said.

Ms Vincent-Pietsch said the lab employees' work was of national importance and keeping them in the dark on their future was "deplorable".