[2018] NZEnvC 093 Tuwharetoa Maori Trust Board v Waikato Regional Council [pdf, 1.9 MB]
...[24] Injection wells for the Nga Awa Purua plant were initially relatively shallow (500 to 1000 m depth) and tapped into an intermediate aquifer. Injection into the intermediate aquifer resulted in a build-up of pressure in this aquifer and in response injection was shifted to deep wells on the edge of the field. Injection was further shifted to a new area in the south of the field in 2008 following tracer testing which showed relatively fast return of injection fluid from the new d...