Fuel contamination detected in groundwater off the Cowra Depot fuel station in Campbell St has prompted the Environmental Protection Authority to assess the site.
The assessment comes as the EPA monitors the results of efforts to remedy fuel contamination at the decommissioned Shell fuel depot site at 34 Brougham St.
The two sites appear on an EPA list of contaminated sites notified to the authority, dominated by service stations and fuel depots in NSW.
An EPA spokesperson said groundwater monitoring in 2008 showed a localised plume of fuel impacted groundwater adjoining fuel tanks at the Cowra Depot, owned by Reliance Petroleum, a wholly owned subsidiary of BP.
The EPA has said contamination occurred mainly on the site with minor contamination detected off site in groundwater.
The authority expects to finish assessing the site following the next round of monitoring results due early this year.
Routine monitoring detected small quantities of hydrocarbon [fuel] in samples collected from a monitoring well located near a diesel dispenser on the site at Campbell St, a BP spokesperson confirmed.
BP said it is monitoring the situation and is keeping the EPA fully informed.
BP will develop and implement a remediation program of extraction events to remove the fuel, and will continue with monitoring of the groundwater in order to check that the plume doesn’t migrate towards the site’s adjacent creek, the EPA said.
Meanwhile the authority is regulating the Shell fuel depot site, owned by Shell and now decommissioned, at 34 Brougham St after remediation was largely completed in July 2009.
“The effectiveness of the remediation is being monitored to determine if it reaches its end point,” the EPA spokesperson said.
“The purpose of post-remediation monitoring, which is the current stage of the site, is to gather adequate information over time to confirm the residual site contamination no longer poses an unacceptable risk to human health or the environment.”
She said groundwater monitoring results indicate the hydrocarbon [fuel] groundwater will not discharge into Waugoola Creek.
“Waugoola Creek and the adjoining areas have been monitored extensively before, during and after the active remediation.
“Information made available to EPA to date does not suggest the site contamination has adversely impacted on the creek.”
She said Shell has complied with the voluntary remediation proposal it made for its decommissioned fuel depot, and used several well-established environmental consultants during the remediation.
The onsite groundwater contamination area has shrunk substantially and appears to be stabilised, subject to ongoing monitoring, the spokesperson said.
“The offsite plume has been in the form of pockets of localised contamination due to the geological conditions of the area.
“These pockets of localised contamination have also shrunk during the course of the remediation.”
The EPA said it is satisfied with the site’s stabilisation subject to ongoing monitoring.
“Once EPA is fully satisfied the site residual contamination poses no unacceptable risk to human health or the environment, we will formally conclude our regulation of this site.
“Otherwise we may enter into new [voluntary management proposal] with Shell to address any residual issues.”
A Shell spokesperson said the company has a thorough process to assess if remediation is needed at decommissioned sites.
“If remediation is needed the company develops clean up plans which meet regulatory requirements,” he said.
“Shell is working closely with the company’s environmental consultant and an accredited auditor to satisfy the requirements of that plan.”
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