Removal of Hopeland excavation caution zone
23 January 2018
Recent testing by the Department of Environment and Science (DES) has shown a decline in hazardous soil gas contaminant levels in the Hopeland area, near Chinchilla.
As a result, DES has removed the excavation caution zone (ECZ) and investigation area because of the reduced severity of risk to landholders.
DES has conducted more than 1850 soil gas tests since 2015, with the most recent results showing an overall reduction in soil gas contaminant levels.
DES has also conducted 46 farm health assessments that sampled air, soil, surface water and groundwater on a number of landholder properties within the soil gas contamination area. To date, that testing has not revealed any associated impact.
The Queensland Government will continue to offer farm health assessments for landholders across the region.
Testing continues to confirm that human health is not impacted and neither are local drinking water supplies, air quality or agricultural products.
This year, DES will continue to sample soil vapour bores and groundwater.
The ECZ was put in place in February 2015 when contaminant gases were detected in soil in the Hopeland region.
In February 2017, an investigation area was established after ongoing testing revealed contaminant gases in the soil at levels below two metres, outside the ECZ.
Despite testing showing a decreasing risk to landholders, some potential risk remains.
As a precaution, landholders excavating soil at a depth greater than two metres are still encouraged to conduct site-specific risk assessments and consider DES’ cautionary advice.
Risk minimisation measures for landholders to consider include:
- obtain advice on potential risks of excavation and measures that should be put in place to deal with the risks
- avoid working alone during excavation works
- monitor gas levels during works, particularly at the point of ground disturbance
- ventilate areas of disturbance and confined spaces to disperse and dilute gases
- establish a buffer zone around works and remove all ignition sources
- assess activities to ensure compliance with Workplace Health and Safety requirements.
The Queensland Government has set aside $20.9 million towards rehabilitation, and this includes regular environmental testing.
Information relating to DES’s management of soil gas contamination can be found at www.ehp.qld.gov.au/management/hopeland/.