First Environment implemented a comprehensive remedial investigation at a former gasoline fill station located in a mixed-use area in Short Hills, New Jersey. The investigation activities included the installation of more than 25 soil borings and two additional monitoring wells to determine the extent of impact associated with historical discharges from four former gasoline underground storage tanks (USTs). Upon completion of the remedial investigation, First Environment conducted a thorough remedial alternatives analysis to determine the most appropriate strategy to achieve regulatory closure. Based on the findings of the RI and subsequent pilot testing activities, First Environment proposed the installation and operation of a Soil Vapor Extraction/Air Sparge (SVE/AS) System to address petroleum and groundwater impact. The results of the RI and proposed remedial action were included as part of the Remedial Investigation Report and Remedial Action Workplan.
In January 2014, First Environment supervised the installation and startup of the SVE/AS System, which consisted of a mobile trailer connected to six SVE and five AS wells. Since system installation, First Environment has provided continual operation, maintenance, and monitoring (OMM) in order to ensure proper operation and to determine system efficacy with respect to the remediation of petroleum impact. Based on the results generated to date, total volatile organic compound (VOC) concentrations, including benzene, in groundwater have decreased by 98%. At this time, the system continues to operate to address low-level petroleum-related compounds in soil.
Subsequent to system shutdown and decommissioning, First Environment will conduct comprehensive soil and groundwater sampling events to evaluate post-remediation conditions. The results of the post-remediation sampling events will determine to appropriate strategy (i.e., unrestricted or restricted) for regulatory closure. The results and findings of the remediation phase will be incorporated into the forthcoming Remedial Action Report, which will be accompanied by an AOC-specific Response Action Outcome.