It could be several more weeks before the last of the oil that spilled into Halifax harbour from a neighbouring power plant is removed.

Just over 24,000 litres of sticky bunker C fuel leaked from a pipe Aug. 2 at the Tufts Cove Nova Scotia Power generating station into the harbour.

Booms and absorbent materials were used to contain and remove the fuel.

All the oil along the shoreline outside the Dartmouth plant's property has been cleaned up, said Nova Scotia Power.

The last part left to deal with is a 150-metre section of a rock wall located directly in front of the plant.

"We weren't happy with how we could get under the rocks," said Mark Sidebottom, Nova Scotia Power's chief operating officer. "So we're removing [the rocks] and replacing them."

Mark Sidebottom is the chief operating officer of Nova Scotia Power. (Robert Short/CBC)

That work is expected to take a few more weeks.

Sidebottom said the booms in the harbour will remain in place as a precaution until provincial regulators sign off on the cleanup.

Regulators were on site Thursday "and having a look at every metre of shoreline," he added.

The utility is still looking into the cause of the leak.

Crews also continue to examine all the fuel pipes on the Tufts Cove property.

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