Background
From the 1950s until 2002, the Public Transport Authority (PTA) leased railway land to private entities that operated a service station at 2291 Albany Highway, Gosnells. During this time contaminants (from common retail fuel products) leeched into the soil and groundwater. The contaminants are not considered to pose a risk to the community if they remain on site; however, they could have adverse affects on human health or the environment if the impacted groundwater was to be used for irrigation from household bores.
The contaminated site (located directly north-west of the Gosnells Police Station building), is currently fenced and used by the police station for overflow staff parking.
Remediation works
In October 2014, the PTA started remediation works to treat the ground contamination, through a process called solvent-enhanced in-situ chemical oxidation. This involves pumping organic solvent and oxidants into the soil to convert hydrocarbon contaminants into less harmful products such as carbon dioxide and water.
The works were completed and some additional remediation has been undertaken, involving skimmers and suction trucks to physically remove remnant hydrocarbon contaminants from wells in the soil. The status of the site, and of the plume of dissolved hydrocarbons in the groundwater, are still being monitored.
Removing the soil and groundwater contaminants will reduce the risk of hydrocarbon vapours affecting those in immediate proximity, and will allow the area to be re-classified for possible productive use.