How will pilot wells be capped if no longer useful or required?
All coreholes are plugged and abandoned as described on page three of the Exploration Core Hole Drilling Factsheet. Pilots are shut in (using the valves on the well head) when the pilot test is completed. Current regulations allow Santos one year to decide whether they will continue to use the well or plug and abandon it as described above. • We are concerned that cementing off core holes will not work. A solid block of cement will not move with the underground movements, resulting in cross-contamination of aquifers. The Hunter Mooki fault line is an inactive geological feature that was last active 200-300 million years ago, prior to dinosaurs. Current stress magnitudes are insufficient to cause reactivation or new faulting. Cementing of core holes with single and double steel casing does provide a sufficient barrier to enable formations to be isolated, avoiding cross-contamination of aquifers.
