-  The cement and shoe track barriers – and in particular the cement slurry that was used – at the bottom of the Macondo well failed to contain hydrocarbons within the reservoir, as they were designed to do,  and allowed gas and liquids to flow up the production casing; -  The results of the negative pressure test were incorrectly accepted  by  BP and Transocean, although well integrity had not been established; -  Over a 40-minute period, the Transocean rig crew failed to recognize and act on the influx of hydrocarbons [...]