Partnering with Puma Energy to Remediate Groundwater
A Puma Energy gas service station in Narangba, Queensland, Australia, was found to contain legacy groundwater contamination, including the presence of LNAPL (or light non-aqeous phase liquid) and dissolved phase hydrocarbons consistent with fuel loss events. Investigations undertaken by the company indicated a dissolved phase hydrocarbon plume both beneath the active station and extending off-site, beneath a neighboring residence. CDM Smith and Puma Energy worked with Australia's Department of Environment Heritage Protection (DEHP) regarding actions required to limit the potential for human health and environmental harm and to maintain environmental responsibility.
To assist Puma Energy in satisfying DEHP requirements, and consistent with the National Environment Protection Measure recommended risk-based approach, CDM Smith enhanced the level of confidence in the proposed remedial approach that was practical, warranted and scientifically defensible.
Our proposed approach sought to obtain a sufficiently detailed understanding of the hydrogeological conditions beneath the site to allow for the development of a cost-effective and justifiable remedial strategy—one that provided environmental protections for the commerical site, the neighboring residential properties and the broader environment alike. Our remedial plan provided information on groundwater flow contaminant transport rates across the site, which helped predict the extent of groundwater impacts beyond the site boundary, based on a number of remedial scenarios. This approach, in conjunction with the current risk assessment process, enabled Puma Energy to prepare clearly defined remedial goals that met the DEHP requirements and environmental responsibility objectives.