An extensive hydraulic fracturing program has been ongoing in the Australian Cooper Basin since 1994. Close to 100 "vertical" wells have been treated during this period in a high temperature/pressure hard rock sandstone environment, with a placement success rate of around 90%. The remaining 10% have almost all experienced some degree of high Near-Wellbore Pressure Loss (NWBPL), ie. 600–1500 psi, with this near-well fracture complexity preventing the placement of treatments. Despite the focus and publicity on this subject in recent years, severe and consistent NWBPL problems in vertical wells are "rare". Exceptions to this are highly naturally fractured formations (coal seams) and/or poor perforation practices. While it is often difficult to determine the exact cause of NWBPL, an understanding of its’ potential causes, coupled with field trials and accumulated experience in the Cooper Basin, has been distilled to obtain a set of tools and procedures to minimise its’ impact on all but the most severe cases.

Summaries of the Cooper Basin field trials conducted over the past five years are presented. This paper also introduces a cost effective, NWBPL management strategy based on the results from these trials that has been successful in over half of the problem wells. This strategy is based on a three-phase approach. It requires the use of NWBPL mitigation, remediation and tolerance initiatives.

Finally this paper presents three case studies in which the NWBPL management strategy has been successfully employed.

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