Najarian Associates designed, installed and operates a state-of-the-art, soil and groundwater treatment system at an industrial facility located in Neptune, New Jersey.  The function of the system is to mitigate residual gasoline contamination due to a leaking underground storage tank.  The complicated geology of the site precluded the application of conventional treatment systems. Najarian Associates conducted a comprehensive Remedial Investigation (RI), which revealed the presence of impermeable soil layers and lenses that partially separated a shallow perched aquifer from an underlying aquifer.  In addition, the presence of potable water supply intakes located down-gradient from the site necessitated an aggressive approach to contain plume migration in both the shallow and deep aquifers.   A passive approach utilizing natural attenuation processes was not deemed appropriate, given the sensitivity of this site.

The treatment system consists of 10 multi-phase groundwater recovery and soil vapor extraction points installed at various locations throughout the site.  The extracted groundwater, free-product and vapors are separated and treated in a self-contained unit.  Components of the system include transfer pumps, equalization tanks, oil-water separators, air-water separators, sediment traps, air strippers, liquid and vapor-phase granular activated carbon adsorption units, and a thermal catalytic oxidation unit. The entire system is linked to a sophisticated computer system, and is operable from any remote location using a laptop computer.

The overall approach to site remediation was divided into two phases.  The first phase entails an aggressive remediation of soils and perched groundwater within the site’s upper aquifer, which is the source of potential contamination to the deeper aquifer.  It is anticipated that upon successful remediation of the upper aquifer, natural attenuation would be a viable solution to rid both aquifers of contamination.  This is based on site characterization conducted during the RI phase of the project.  However, due to the presence of sensitive water supply receptors downgradient of the site, the treatment system has been designed and installed to address both shallow and deep aquifers.   The entire project is being implemented under direct oversight from NJDEP’s, Bureau of Underground Storage Tanks.                                         

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At a gasoline station site located adjacent to the environmentally sensitive Navesink River, Najarian Associates implemented a comprehensive soil and ground water remediation program.  To delineate the site's subsurface plume, fourteen soil borings, seven monitoring wells and and sixteen piezometers were installed.  Also, an on-site mobile analytical laboratory was installed.  The field measurement program revealed that several petroleum-based contaminants were present in the soil at levels exceeding relevant NJDEP standards.  A Remedial Investigation/Remedial Action Workplan (RI/RAW) was prepared for the site and submitted to NJDEP for review.  The approved plan called for the installation of an in-situ soil and groundwater treatment system to intercept free product that was migrating towards the River.  The plan also provided long-term remediation for the site by removing both dissolved and adsorbed phase contaminants.

An example of remote monitoring capabilities is provided by a groundwater remediation project conducted by our staff at a former sand and gravel mining site.  Preliminary investigations revealed fourteen areas of concern at the site involving various levels of soil and groundwater contamination.  Sampling at the site revealed a TCA (tetrachloroethene) contaminated groundwater plume.  To meet an ambitious construction schedule, the Najarian team conducted a fast-tracked remediation program.  To this end, the team installed a groundwater remediation system consisting of a cyclic pump-and-treat system and a state-of-the-art air-sparge system.  In addition, a remote telemetric and video monitoring system was installed to maximize the efficiency of the operations.  Due to an intense and successful collaboration with the NJDEP case manager, the entire remediation system was operated under permit-by-rule regulatory oversight. Consequently, a No Further Action (NFA) letter was obtained within three days of submission of the final closure report.