Enbridge on Friday entered into an agreement with Suncor Energy to expand existing infrastructure at the Athabasca terminal to accommodate higher bitumen volumes from Suncor’s Firebag 3 and 4 developments.

The approximately $150 million expansion is expected to be in-service in the second quarter of 2013.

Enbridge will construct a new 350,000 bbltank as well as additional infrastructure including new booster pumps, meters and modifications to existing piping and manifolds.

To meet Suncor’s required in-service date, Enbridge began construction in July 2011.

Suncor has agreed to underpin Enbridge’s investment in these facilities through a long-term services agreement, the companies said, during which Enbridge recovers all operating costs, a return on equity and all of its invested capital.

“We’re pleased to further strengthen our relationship with Suncor by delivering timely and innovative terminal and transportation services,” said Steve Wuori, president of liquids, pipelines and major projects for Enbridge.