and its subcontractors, in order to save money led to blind faith and a success fful cementing jo. first of all, bp chose a riskier well design, and the chairman, chairman waxman talked about this for a moment. the best practice would have been to use a liner and a tieback which provides four barriers to prevent the flow of dangerous hydrocarbons to the well head. instead, bp, as the chairman said, chose a long string approach which has only two barriers. an internal document of the company warned that this approach was not recommend ed. it says cement simulations indicate it's unlikely to be a