Independent testing to measure background levels of methane in the air in the Gloucester region, commissioned by AGL Energy Limited (AGL) at the request of Gloucester Shire Council, has found levels are “typical of regional areas”.
Using a highly accurate vehicle-mounted laser spectrometer, air samples were taken by Pacific Environment for a total of 80 hours (in one second measurements) while covering local routes totalling 3,200 kilometres between July 2013 and May this year. The methane monitoring was undertaken before, during and after drilling and hydraulic fracturing of wells at the Waukivory Pilot Project.
Gloucester Gas Project Director, Nigel Bean, said today: “The report found the average methane concentration over the entire monitoring period was 1.8 parts per million which is consistent with the global average background level as established by the World Meteorological Organisation.”
“The highest methane readings were recorded near Gloucester’s sewage treatment plant and in residential areas where methane levels are typically slightly higher,” he said.
“The study also found that there has been no change in background methane levels from when baseline monitoring was conducted in 2013 to the period during and after hydraulic fracture stimulation of the Waukivory Pilot wells,” he said.
By analysing the levels and isotopic signature of the methane detections, the land use activities that had methane concentrations higher than the background levels in the Gloucester region were identified as livestock, landfill, coal mining, the local sewage treatment plant and biological activity.
The study also found:
- There was negligible difference observed between the methane concentrations measured inside and outside of the Gloucester Basin
- Hydraulic fracture stimulation and gas flaring saw no changes in methane concentrations.
“Aside from the fact that there are no known health effects associated with methane at the concentrations measured, these findings should provide a high level of assurance to the community of Gloucester and its surrounds that our gas pilot program is not causing any increase to methane levels in the local atmosphere,” Mr Bean said.
The full report can be viewed here.