ESTCP Report: Post-Remediation Performance Assessment at a Petroleum Impacted Site

Official ESTCP Audio Summary. https://www.youtube.com/watch?v=HREpiJpzsp8

This is a detailed report about an investigation at a Navy Air Station in which a multi-tiered approach was used to address: i) Site characterization focused on the residual risk due to LNAPL composition, ii) LNAPL recovery and mobility based on transmissivity, and iii) NSZD rate quantification using E-Flux CO2 traps. The primary objective was to help the US Department of Defense (DoD) make a stronger case for the closure of legacy petroleum sites using risk-based decisions.

The report documents descriptions of the technologies used, cost and performance assessments, and implementation issues. Based on solid data, this report documents that NSZD is a feasible remedy of comparable efficiency to active remedies that had met their design performance. Four remedial alternatives were considered: i) Land Use Controls/Institutional Controls after NSZD/MNA evaluation, ii) NSZD/MNA, iii) bi-weekly free product recovery using manual bailing/skimming before transitioning to NSZD/MNA, and iv) dual phase extraction followed by NSZD/MNA. Based on a cost analysis for 15 years, NSZD/MNA was about 2x more expensive than LUC/IC/NSZD/MNA, but approximately 2.5 to 5 times less expensive than the active remedies considered.

The report concludes the transition to a more passive remedy could result in significant cost savings, while maintaining an adequate risk management.

see the full study