- Conduct environmental due diligence for acquisition
- Review condition of bulkhead and marina
- Perform investigations of soil and concrete to delineate release of PCBs
- Integrate environmental remedial action planning with site development
- Prepare final RAP to CT DEEP and EPA
- Design and manage remediation of PCBs in soil through excavation
- Design concrete slab to cap remaining PCBs
- Prepare Dewatering Plan and obtain DEEP General Permits
Challenge
The 3-acre property, located in South Stamford, CT along the East Branch of the Stamford Harbor, was underlain by fill material dredged from the adjacent canal between the mid-1800s and the early to mid-1900 that had been impacted by historical manufacturing activities. The approximately 30,000-square foot two-story site building, which was constructed c. 1920s, was constructed on concrete piles above a crawlspace which contained soil contaminated with polychlorinated biphenyls (PCBs) at concentrations significantly above state and federal remedial action levels in certain locations and was subject to daily incursions from the tide. The proposed development included keeping the existing structure and adding two floors which required installing over 400 piles within the building footprint and through the PCB-contaminated soil. The combination of complex environmental and structural conditions, the waterfront setting, and the regulatory requirements for remediation required an experienced project team with a diverse set of technical skills.
Solution
During initial phases of the project, GZA participated in negotiations with the former owner regarding the extent of remediation warranted by site conditions and developed cost estimates for reaching regulatory closure under the Connecticut Transfer Act and for achieving compliance for PCBs under EPA’s Toxic Substance Control Act (TSCA). GZA designed and implemented remedial actions to address PCB contamination beneath the site building as part of the redevelopment including soil excavation and dewatering. A concrete slab was then installed to cap residual PCB impacts beneath the building and a deed restriction was recorded to prohibit disturbance of the cap.
Benefit
By skillfully responding to changes in site conditions and to the proposed project during construction, GZA was able to provide the flexibility, services and management skill required to help move this high-profile, challenging project forward to a projected on-time completion date. Stamford Media Village is involved with post-production of content for programs such as HGTV and History Channel and will be bringing around 400 jobs to this location once the building is completed.