Another major incident investigation finds serious cultural failures, poor training for operators and emergency responders, poor emergency planning, and technical failures in the Mechanical Integrity program. The crude oil pipeline company’s pervasive organizational failures caused a massive 2010 spill in Michigan, a National Transportation Safety Board (NTSB) preliminary investigation has found. The investigation found that multiple small corrosion fatigue cracks grew in size and linked together (MI inspection failures), causing a breach more than 80 in. long in the pipeline on July 25, 2010.