WEST SACRAMENTO (CBS13) — The demolition has begun of the Shell petroleum tank farm in West Sacramento, city officials say.

A deal was reached back in 2017 with the Port of West Sacramento to phase-out operations at the Pioneer Bluff-area tank farm over four years.

The six-acre facility has been in operation since the 1940s.

"This transaction is a big step in the planned de-industrialization of West Sacramento's Pioneer Bluff District," said Yolo County Supervisor and Port Commission Chairman Oscar Villegas in a statement.

It's unclear how long demolition work and clean-up will take.

West Sacramento city officials say the project is an important step in redeveloping the riverfront.