March 10 (Reuters) - The cost of the Canadian government-owned Trans Mountain oil pipeline expansion has jumped 44% from last year's estimate to C$30. In a letter to the government on Friday, the banks said once the expansion is complete TMC is expected to generate earnings before interest, taxes, depreciation and amortization of more than C$2. Keith Stewart, a senior energy strategist with Greenpeace Canada, said buying and building the pipeline would go down as one of the worst infrastructure decisions ever made by a Canadian government