Root Cause Analysis of Wells with Integrity Failures

Abstract A Root Cause Analysis (RCA) is a methodological process of problem solving. In brief, this is an approach of "post mortem" analysis of the consequences with aim to understand what is one single (or multiple) lack of Management System that led to failure. Subsequently we can develop detailed remedial plan and actions to address failed Management System and most importantly prevent reoccurrence. Approach has been widely used in science and engineering. Probably, will be difficult to identify inventors of this analysis however first appearance in engineering discipline credited to Sakichi Toyoda, founder of Toyota Industries. He improved RCA by implementing technique called the "5 whys". Despite obvious benefit and versatility of root cause analysis methodology there are several challenges that might jeopardize result:–Absence of critical data / information due to various reason (time gap, no recoverable samples etc)–Too many variables that not allow to pinpoint main line / chain of investigation–Multiple failures with different root causes–"Depth of investigation" how many "Whys" are efficient to reveal main root cause.