Tui-3H ST1 was drilled by Tamarind Taranaki Limited, in PMP 38158, as a side-track to the existing Tui-3H horizontal producer to target potential by-passed oil in a small satellite structure along the western flank of the Tui Field. The primary objective of Tui-3H ST1 was for it to be completed as a producible well as close as possible to the base of the D shale. Tui-3H ST1 likely encountered a residual oil zone swept by aquifer influx during 13 years of fluid production from Tui-2H and Tui-3H. This was facilitated by an actual reservoir structure that is flatter than prognosed and may have lacked four-way dip closure. Either way, any remaining reserves are too small to be economic.