Approved by decision makers.
That prior to the grant of any further exploration approvals, in order to minimise the risk of groundwater contamination from leaky gas wells:
- all wells subject to hydraulic fracturing must be constructed to at least Category 9 (or equivalent) and tested to ensure well integrity before and after hydraulic fracturing, with the integrity test results certified by the regulator and publicly disclosed online;
- a minimum offset distance of at least 1 km between water supply bores and well pads must be adopted unless site-specific information of the kind described in Recommendation 7.8 is available to the contrary;
- where a well is hydraulically fractured, monitoring of groundwater be undertaken around each well pad to detect any groundwater contamination using multilevel observation bores to ensure full coverage of the horizon, of any aquifer(s) containing water of sufficient quality to be of value for environmental or consumptive use;
- all existing well pads are to be equipped with multilevel observation bores (as above);
- as a minimum, electrical conductivity data from each level of the monitor bore array should be measured and results electronically transmitted from the well pad site to the regulator as soon as they are available. The utility of continuous monitoring for other parameters should be reviewed every five years or as soon as advances in monitoring technology become commercially available; and
- other water quality indicators, as determined by the regulator, should be measured quarterly, with the results publicly disclosed online as soon as reasonably practical from the date of sampling. This monitoring regime should continue for three years and be reviewed for suitability by the regulator.
Action item update
The Northern Territory Government has worked with independent scientific experts to develop a Code of Practice relative to the Inquiry's recommendation. The Code is legally enforceable through the Petroleum (Environment) Regulations 2016. The finalised Code was published on 12 June 2019.
The Code requires proponents to comply with the Preliminary Guideline for Groundwater monitoring bores for Exploration Petroleum Wells in the Beetaloo Sub-Basin which was finalised and distributed on 29 November 2018. The guideline has been uploaded to the DEPWS website.
Monitoring has commenced in Beetaloo Sub-basin to enable the 6 month baseline monitoring requirement to be achieved.