Site Investigation and Remediation | Former Plating Facility RCRA Corrective Action Site
GeoInsight was retained by a large, international multimedia company to conduct a wide range of environmental services to achieve closure of former chromium plating facility regulated under RCRA. GeoInsight’s extensive experience with the state and federal regulatory requirements and the Connecticut Transfer Act were a key asset in helping this client achieve closure of this complicated site.
Successfully coordinated CTDEEP and USEPA programs – We worked with the client, CTDEEP, and USEPA to enter the site into the RCRA Corrective Action Program (CAP) to help achieve regulatory closure outside of the traditional RCRA process.
Preparation of remedial plans – Following the field investigations, we prepared detailed remedial and closure plans for the EPA under the CAP program. Under the CAP, we helped the client achieve four significant milestones, including meeting groundwater.
Remedial oversight and ELUR – Following regulatory approval of our remedial plans, we oversaw the contractors during the remedial phase. Our plan included the collection and analysis of soil samples to meet CTDEEP closure requirements. To meet regulatory requirements for impacted soil beneath the former building and lagoons, we prepared an Environmental Land Use Restriction (ELUR), which was approved by the CTDEEP.
Regulatory Closure – We helped the client achieve regulatory closure through the Connecticut Transfer Act Program and are currently assisting with closure through the RCRA CAP.
Scope of Services
- Site Investigation Activities
- Connecticut Transfer Act
- Groundwater Plume Delineation and Monitoring Program Development
- State and Federal Regulatory Coordination
Technical consulting and field investigation activities – GeoInsight performed comprehensive assessments to evaluate current and former environmental conditions at the property, including reviewing investigation and remediation work conducted by previous consultants. Based upon this information, GeoInsight conducted Phase II and III subsurface investigations to assess ten environmental areas of concern (AOCs), primarily attributed to the former chromium plating operations. The investigation activities included preparation of detailed investigation plans, investigation of soil and groundwater quality at each AOC, and delineating identified impacts to soil and groundwater from petroleum and plating-related compounds. The results of the investigations were used to develop comprehensive remedial approaches for identified impacts to the subsurface at four of the AOCs. These remediation areas included the former metal hydroxide sludge lagoons, as discussed below.
Remediation activities and environmental land use restriction – Following delineation of the residual metals impacts in the former metal hydroxide sludge lagoons, GeoInsight prepared a detailed remedial action plan (RAP) for submittal to the CTDEEP. The objective of the RAP was to remediate the identified impacts in at the Site in accordance with Connecticut Transfer Act and CTDEEP requirements. The remediation included the excavation and off-site disposal of hexavalent chromium-impacted soil and the implementation of a monitored natural attenuation program for groundwater. During the remediation process, GeoInsight conducted a comprehensive post-remediation soil sampling program in accordance with the RAP. Following the remediation, GeoInsight prepared a detailed RAP Summary Report for submittal to the CTDEEP. The report documented the remediation activities and provided a groundwater monitoring program to help achieve regulatory closure for the site. As part of the remedial approach for this site, GeoInsight implemented an Environmental Land Use Restriction (ELUR) for the property. After receiving approvals by the CTDEEP, this mechanism was used to help achieve regulatory closure by allowing certain hexavalent chromium-impacted soils to be left beneath the current paved parking area at the site.
Groundwater plume delineation and monitoring program development – During the field investigation activities, we installed a monitoring well network across the site to evaluate the vertical and horizontal components of groundwater flow, delineate the extent of the dissolved hexavalent chromium plume, and evaluate threats to downgradient groundwater receptors include surface water bodies and potential drinking water supplies. These activities were required under Connecticut Regulations and the RCRA CAP. Monitoring was conducted on a quarterly schedule and results indicated that the dissolved hexavalent chromium impacts decreased over the course of the monitoring program. Downgradient receptors were not affected by the dissolved hexavalent chromium plume.
Regulatory program compliance and closure – During the course of the project, GeoInsight prepared detailed investigation and remediation summary reports for submittal to the CTDEEP and USEPA, as required. Following the completion of the above remediation activities, groundwater compliance monitoring, and implementation of the ELUR, a GeoInsight Licensed Environmental Professional (LEP) filed a detailed Verification with the CTDEEP to achieve regulatory closure of the environmental issues. GeoInsight is currently working with the client and CTDEEP to close the site under the RCRA CAP.