Background
Lock the Gate Alliance challenged Tamboran B2’s shale gas exploration project in the Beetaloo Sub-basin, Northern Territory, seeking an injunction under s.475 of the Environment Protection and Biodiversity Conservation Act 1999 (Cth) (EPBC Act). The applicant argued that the project, involving hydraulic fracturing of wells to extract gas from the Velkerri Formation, was likely to have a significant impact on the Cambrian Limestone Aquifer system and therefore required Commonwealth approval under Part 9 of the EPBC Act. Tamboran held Northern Territory exploration permits and had obtained NT environmental approval but had not sought Commonwealth approval, asserting it was unnecessary. The Cambrian Limestone Aquifer, sitting above the gas-bearing formations, is a critical freshwater resource providing groundwater to pastoral and local communities and supporting baseflow in the Roper and Flora rivers.
The EPBC Act prohibits unconventional gas development likely to have a significant impact on water resources unless Commonwealth approval is obtained. Tamboran had made no such referral to the Commonwealth Minister and proceeded without approval, thereby creating the legal risk at issue. The applicant challenged whether this constituted a violation of s.24D of the EPBC Act.
The Court’s Holding
Justice Owens dismissed the proceedings, finding that the applicant failed to prove on evidence that Tamboran’s activities were likely to have a significant impact on water resources. The court established important principles: “likely” in the EPBC Act means “a real or not remote chance” rather than “more probable than not.” The burden remained on the applicant to prove a significant impact; Tamboran need not prove its wells were safe, but the risk assessment must consider the wells as designed and constructed, not hypothetical alternatives. The court found insufficient evidence of either a substantial risk of well integrity failure or of aquifer contamination from hydraulic fracturing fluids or released hydrocarbons.
The court clarified that “significant impact” means something “important, notable or of consequence,” excluding minor or negligible effects. It must be assessed across all aspects of the water resource—organisms, ecosystems, and dependent systems—not merely human uses. The court rejected the applicant’s framing that Tamboran bore a special burden to prove efficacy of its well design, finding no meaningful difference in the parties’ access to technical evidence and expertise.
Key Takeaways
- The EPBC Act’s unconventional gas provisions require Commonwealth approval when activities are likely to have significant impacts on water resources, but applicants must prove this likelihood on evidence
- “Likely” means a real or not remote chance, not merely probable, but still requires substantive proof rather than speculation about hypothetical risks
- Well design, construction standards, and engineering safeguards are relevant to assessing actual risk; courts will not assume worst-case scenarios absent evidence
- A project’s stated purpose (exploration vs. production) and existing regulatory approvals define the scope of the “action” being assessed for environmental impact
Why It Matters
This decision clarifies the legal pathway for Commonwealth environmental scrutiny of onshore gas projects and establishes the evidentiary threshold applicants must meet. For Australia’s emerging Northern Territory unconventional gas sector, it demonstrates that robust hydrogeological and engineering evidence can support regulatory approval decisions, even where environmental risk exists in theory. The judgment reinforces that EPBC Act challenges require concrete technical proof rather than precautionary arguments about possible contamination.
The decision is significant for energy development generally: it shows both that the EPBC Act’s water resource protections can be deployed strategically and that defenders of such projects have a viable path to establish that risks, while not zero, do not rise to “significant impact” levels. For environmental advocates, the case illustrates that while Commonwealth jurisdiction exists under the EPBC Act, succeeding on its terms requires sophisticated expert evidence about geology, hydrology, and well mechanics rather than general environmental concerns.