(Adds comment from Enbridge in second paragraph)
CALGARY, Alberta, Feb 21 (Reuters) - Part of the shut Enbridge Inc ENB.TO 2A pipeline in Alberta will need to be drained for several days, Canada's National Energy Board said on Tuesday, and it is not clear when shipments will resume.
Enbridge will repair the line after the ongoing cleanup and has made "significant progress" in recovering the 200 cubic meters (7,063 cubic feet) of spilled condensate, the company said.
The 959-km (586-mile) pipeline, which transports light crude as well as condensate between Edmonton and Hardisty in the province of Alberta, was shut following a leak in Strathcona County last week.
Enbridge has said the line was struck during unrelated construction activity in the area by TransCanada Corp TRP.TO and its contractor, the privately held Ledcor Group of Companies.
TransCanada said a release was detected when its crews were working in the area, but did not say who detected the release. The company is conducting an internal investigation, it said.
Ledcor did not respond to a request for comment.
The NEB said about 490 cubic meters of oil condensate had been recovered. The total amount recovered will exceed the 200 cubic meters spilled because 20 km of the 24-inch (61-cm) 2A pipeline will require draining, the regulator said.
The regulator said there was no public impact, and no worker safety incidents were reported.
"No NEB enforcement actions have been taken as the incident is still being investigated," the regulator said.
Enbridge said an excavation pit that was used to contain the leaked condensate has been emptied using vacuum trucks.
Enbridge said on Monday downstream operations were normal, but there was no estimated date for restarting the line. The company will work with customers to mitigate any impact on their operations, it said.
A shipper on Line 2A said his company's volumes so far were not affected.