PERTH (miningweekly.com) – ASX-listed AGL Energy has suspended pilot production testing at its Waukivory coal seam gas (CSG) pilot project, in New South Wales, after benzene, toluene, ethylbenzene and xylenes (BTEX) were detected in flow-back water from two of the four wells, and from an above-ground water storage tank.
The company told shareholders that the BTEX chemicals had previously been found in baseline groundwater tests carried out before the commissioning of the Waukivory pilot project, at levels of between 30 parts per billion (ppb) and 60 ppb.
Four of the five samples now taken, found BTEX concentrations ranging between 12 ppb and 70 ppb, while the fifth sample found BTEX concentration of 55 ppb. AGL said that the integrity of the samples was being reviewed.
Despite the decision to voluntarily suspend the pilot production testing, AGL said that none of the hydraulic fracturing (fracking) fluids used at Waukivory contained any of the BTEX components, with the chemicals most likely occurring naturally from within coal seams, and brought to surface as part of the flow-back water from the fracking process.
The company noted that all flow-back water is captured within a fully contained system, and deposited in an above-ground storage tank, before treatment.
AGL said its monitoring of groundwater and surface water had shown no evidence of change in water quality since the start of the Waukivory pilot programme.
The New South Wales state government last year announced plans to overhaul its CSG industry, revealing plans to pause, reset and restart gas exploration in the state, implementing a strategic framework to deliver a well-regulated CSG industry.
Under the new legislation, the entire system for petroleum exploration licences would be reset, with the New South Wales government now deciding which areas would be released for exploration, and to whom.