Poisoned garden ... Dominico Ursino has lost his crop for the first time in 50 years.

Poisoned garden ... Dominico Ursino has lost his crop for the first time in 50 years. Photo: Lee Besford

A SPATE of dying trees and vegetable gardens across Girraween, near Blacktown, has sparked an investigation into the possible leaching of herbicides from the nearby plant of the chemical production company DuPont Australia.

Samples taken from soil and dying vegetation by the Office of Environment and Heritage have revealed ''that many of the dead and dying trees in the area have been affected by a herbicide that is normally used on grain crops''.

The office has warned residents that there may be further die-back of vegetation in coming warmer months as the herbicide can lie dormant in plants in winter.

A long-time Girraween resident, Dominico Ursino, has lost his entire vegetable garden. The Calabrian migrant, who has proudly grown all his own vegetables for the past 50 years, has watched them die mysteriously this season. He has planted another batch of cucumbers and tomatoes and hopes they will fare better than the last crop.

The Office of Environment and Heritage (OEH) has written to residents telling them the levels of herbicide found in the neighbourhood pose no risk to human health.

The office's metropolitan director, Giselle Howard, said it was now reasonably suspected that DuPont may be responsible for the contamination and the company has been issued with a prevention notice.

But DuPont believes its Girraween plant is not to blame and says there is nothing to indicate an emissions control problem.

''We are also conducting our own investigation regarding vegetation damage and, to date, there is no evidence to suggest there is any link between the vegetation damage and the plant,'' Graeme Longe, managing director of DuPont Australia and New Zealand, said.

Ms Howard said her office's investigations would include the sources of the herbicide, the reason for emissions of the herbicide and a full assessment of monitoring and alarm systems and response protocols at the DuPont plant.

''We want to make sure that every aspect of the site is placed under the microscope to ensure the facility is operating as safely and efficiently as possible," Ms Howard said.

The prevention notice formally required DuPont to undertake a thorough investigation of its operations and convince the office that it was not responsible for the die-back.

"OEH will take whatever regulatory action is needed in this matter,'' she said.

In a statement released yesterday, Mr Longe said DuPont had been operating at the Girraween site for 40 years without any environmental breaches. The company is required to report any non-compliance breaches to the OEH.

''We maintain a rigorous monitoring program of our emission control processes and our records also show that there have been no spills, leaks or escapes of materials from the premises that we are aware of.''

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