AWE Limited provides the following update on its groundwater monitoring program at the Drover-01 exploration well site located in the Shire of Coorow, approximately 18km southeast of Green Head and 220km north of Perth.
The initial phase of AWE’s groundwater monitoring program at Drover-01 involved testing for 86 analytes, sourced from four different locations. Results to date have shown no irregularities from 342 of those 344 tests. Irregular readings were measured for methane at two locations and were most likely the result of a difference in sampling methodology between the tests.
These results, whilst not harmful, were immediately reported to the regulatory authorities and the landowner. AWE then commissioned further testing and independent analysis of the results.
The independent analysis found that although methane readings at the two locations had increased there were no safety or environmental issues associated with the measured levels and that AWE’s Drover-1 exploration well was not the source. The Department of Water has subsequently confirmed that the levels of recorded methane posed no environmental or safety risk.
AWE Managing Director, Bruce Clement, said the testing verified that the Drover-1 exploration well was not the cause of the elevated methane readings.
“We were confident from the thorough assessment and planning processes we used that the Drover-01 exploration well could not, and did not, cause the higher methane levels. The Drover-01 well was not fracked and independent analysis confirms that the methane detected was not sourced from shale gas or naturally occurring reservoir gas” he said.
The independent consultant, Gemec Environmental Consultants, confirmed that the methane was microbial and was not from shale gas or naturally occurring reservoir gas and that the source of the methane in the two wells was different.
Further analysis used isotope testing to determine the origin of the elevated methane in the two monitoring locations. The isotope testing, conducted by the University of Queensland, helped determine that the elevated methane reading at the first location reflected the normal application of materials used to construct a new water bore, consistent with the construction of a typical agricultural water bore. At the second location, ongoing monitoring will confirm whether the methane levels have actually changed or not since initial sampling.
Methane is non-toxic and non-poisonous and there are no screening or threshold levels to apply to the results.
As part of its open and transparent stakeholder engagement approach, AWE also briefed the Shire of Coorow Drover-01 Community Reference Group so local residents understood the monitoring results and were able to raise any questions they had and get prompt responses. AWE is also co-sponsoring the CSIRO benchmark study into groundwater in the Perth Basin.
If you have any questions about the Drover-01 water monitoring results, please contact us.