Remediation of Former Mobil Service Station, Griffith, ACT

Martens were engaged as lead environmental consultant to supervise and document the remediation of a former Mobil service station site at Griffith, ACT.

Martens were engaged as lead environmental consultant to supervise and document the remediation of a former Mobil service station site at Griffith, ACT. Remedial works were required to support future commercial and residential development on the site with a multi-level basement carpark.

Remediation was required due to the site being contaminated with petroleum hydrocarbons, benzene, toluene, ethylbenzene and xylene. Contamination was the result of leaks emanating from the former underground storage tanks (USTs), fuel lines and bowsers. Contamination had impacted site soils and weathered rock, with hydrocarbon product having also migrated to the regional groundwater table located at 12m bgl (as both a light non-aqueous phase liquid (LNAPL) and dissolved phase plume).

Project scope included:

• Supervision of soil and weathered rock remedial works which were undertaken via a combination of land farming and off-site removal
• Installation of a groundwater well field to determine the extent of dissolved phase plume (at its peak this included 32 monitoring wells)
• Supervision of removal of non-aqueous phase liquid via multi-phase extraction
• Quarterly groundwater monitoring events undertaken to plot the distribution of dissolved phase contaminants and determine if natural attenuation was occurring following LNAPL extraction
• Installation and sampling of soil vapour implants to guide human health risk assessment
• Preparation of environmental management plans for the construction and post construction phase of the development
• Design of soil vapour barrier for the proposed multi-level basement carpark