19 April 2012
Tests rule out contaminants at Pacific Highway upgrade
Further test results of samples taken from the Herons Creek to Stills Road upgrade on the Pacific Highway have ruled out a range of contaminants at the site.
Independent chemical specialists confirmed no radioactive material had been found at the site where five workers reported feeling nauseous earlier this month.
Subsequent environmental and contamination assessment reports have today shown the highly oxidisable clay from the site contained no contamination from pesticides, polyaromatic hydrocarbons, petroleum hydrocarbons, polychlorinated biphenyls or any of the volatile organic hydrocarbons.
The metals present were within natural levels and did not exceed the health investigation levels.
The tested material was positive for acid sulphate soil potential. Further investigations are being arranged to determine what the odour given off by the clay when it oxidises in air may be.
Acid sulphate soil is common along the New South Wales coastline. It is a type of naturally occurring soil which can produce gas and acid.
RMS carries out investigations at major highway upgrades to assess the potential of this type of soil being found at project sites.
RMS has programs in place to address acid sulphate soil detected during excavation work at project sites. This includes ensuring appropriate measures are taken to neutralise the acidity for the safety of workers.