Alsco – Decommission UST Various Sites

Location: Alexandria NSW, Ingleburn NSW, Eagle Farm QLD, Footscray VIC

Division: Energy

End User: Alsco

Client: Alsco

Project manager: Ben McDonnell

Year completed: 2016 – 2019


Underground bulk diesel, unleaded and heating oil storage systems had become obsolete. The facilities were in poor condition with risk of leaking and spill into the surrounding soil. Decommissioning was deemed necessary to prevent/mitigate environmental contamination.

OPEC scope:

OPEC was engaged to decommission underground liquid storage facilities. Where possible OPEC decommissioned ex-situ, capping or removing all connections and excavating the underground tank and dispose off-site and back fill with clean soil. Where removal was not possible/feasible, OPEC decommissioned the tanks in-situ, capping all connections, cleaning the tank internally and filling the tank with foam.


Asbestos was found on the Alexandria site. OPEC followed Asbestos notifications protocol and developed and executed an Asbestos Remediation Plan, resulting in site being validated as clear.

It was discovered at the Ingleburn site that the underground tanks had been previously decommissioned via sand filling. Due to the lack of decommissioning records or soil validation; it was deemed necessary to cut open the tanks and manually excavate the sand and dispose. The site was then backfilled with clean soil and deemed safe. At Eagle Farm the records of underground tanks were deemed incorrect after extensive ground search and exploratory excavation. It was assumed that the tanks had been previously removed but records weren’t updated.