Two days before Canadians learned the federal government was buying Kinder Morgan’s 65-year old Trans Mountain pipeline last month, the pipeline burst 4,800 litres of oil in B.C.’s interior.

That volume is 48 times more than what was first reported by the provincial government when the May 27th spill occurred north of Kamloops, B.C. The government initially said 100 litres escaped – which happens to be the minimum threshold under the company's spill reporting obligations.

Trans Mountain spokesperson Ali Hounsell wrote in a statement to CTV News Sunday that the company didn't tell regulators how much of the “medium sweet crude” had escaped at the time of the spill.

“Trans Mountain had not provided an estimate of the volume spilled, other than to confirm with regulators that it was over the reportable threshold, until cleanup had sufficiently progressed to a stage where an accurate estimation could be provided,” Hounsell wrote in an email.

“Following an onsite investigation, Trans Mountain has provided an updated estimated spill volume to regulators,” she confirmed.

The company says the spill, equivalent to 27 oil barrels, is now in the final stages of clean up at the Darfield pump station.

The B.C. Environment Ministry said at the time that the spill came from a leaking flow meter, and that it was contained to the pump station property. Kinder Morgan shut down the pipeline for several hours on the day the spill, and has since resumed the flow of oil.

Prime Minister Justin Trudeau announced on May 29th that the federal government will spend $4.5 billion to buy the Trans Mountain pipeline with the hopes of completing the further $7.4 billion expansion, possibly with private sector investment, to unlock more Alberta bitumen for world markets.

Kinder Morgan has long stated that the pipeline expansion will bring Alberta oil producers $73.5 billion in new revenues and $46.7 billion in government taxes and royalties.

After Ottawa’s announcement to buy the existing pipeline, Kinder Morgan Canada said pipeline expansion construction in Alberta and B.C. would be restarted soon with the federal government funding it. The sale is expected to close in the second half of 2018.

The deal comes as Kinder Morgan Canada said it is paying $1.5 million in bonuses to its two top executives to ensure they stay with the company as the Trans Mountain pipeline system is sold to the federal government.

The National Energy Board’s spill data shows the pipeline previously spilled 305 litres in Burnaby in 2009, 90 litres in Abbotsford in 2012, and 18 litres at Hope.

With files from the Canadian Press