OTTAWA — Kinder Morgan Canada says expanding the Trans Mountain pipeline could cost the federal government as much as $1.9 billion beyond the company's original construction estimate and take 12 months longer to finish.The figures are included in documents the company filed Tuesday with the United States Security and Exchange Commission related to its plan to sell the pipeline to the Canadian government for $4.5 billion.The sale price does not include how much more Canadians will pay to finish twinning the pipeline between Alberta and British Columbia.