Investigations into an illegal waste dump south of Kaniva have so far uncovered at least twenty industrial waste containers buried underground.
Victoria's Environmental Protection Authority has released more information into its investigations into the 1400-acre property on Kaniva-Edenhope road.
It follows a community information session in town in July.
Regional Manager North West Dr Scott Pigdon said chemical vapour testing had revealed no gasses from the suspected chemical waste had been had made it to the surface.
"It shows no signs of contamination, nor is there a risk from chemical vapours," he said.
"While the EPA is still assessing the nature and the amount of waste hidden on the property, the results found so far also show the groundwater is unlikely to be affected."
Dr Pigdon said the body would expand the groundwater monitoring program onto the property itself. He said EPA investigators had used aerial drones fitted with Ground Penetrating Radar to search for buried waste.
He said detailed analysis of the type and quantities of waste that had been dumped were not yet available, and as such a clean up plan could not yet be designed, nor a cost of clean up be estimated.
Media reports on July 19 suggested the property is owned by the same man linked to at least nine other chemical dump sites in Melbourne's north.
"The EPA will direct the landowner to undertake actions to secure the property and understand potential risks on the site, and those actions will lead to the development of a clean-up plan," Dr Pigdon said.
An EPA spokesman said properties surrounding the dump would be included in an emergency management response plan being developed for the area.
He said this was being drafted in conjunction with the Country Fire Authority and the Grampians Regional Emergency Management Team.
The spokesman said more information from the EPA regarding the Kaniva site can be found here.
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