Cabot Koppers Superfund Site Phase 1 Remedial Action
Significant Project Features
- Remediation at 90 residential and commercial properties was successfully completed
- 40,000 CY of impacted soils was transferred to a temporary storage facility at the plant site
- Extensive restoration to each property required close coordination with owner
- Community relations plan focused on close communications with all stakeholders with an emphasis on minimizing disruptions to property owners during execution of the work
- Primary contaminants of concerns were Dioxin with some PAHs and Arsenic
History & Location Details
The site includes the former Koppers wood-treatment facility and the former Cabot Carbon pine-tar products facility in Gainesville, Florida. The Koppers facility, a wood-treating facility that formerly existed on the property, began operations in 1916 with the American Lumber and Treating Company preserving wood utility poles and timbers. Over the years the property changed hands several times. In March 2010, Beazer purchased the real property comprising the Koppers Facility. Over the years, wood-treatment preservatives used at the Koppers facility included creosote, pentachlorophenol, and chromated copper arsenate (CCA). Primary release areas included the former Process (pressure-treatment) Area, the former Drip Track area where wood was allowed to dry immediately after treatment, and two former process-water lagoons. The lagoons were closed and filled.
The facility that existed on the Cabot Carbon portion of the site began production of pine-tar products and charcoal in the early 1900s. Cabot Corporation bought the operation in the 1940s and continued operating the facility. The facility generated of a number of products, including pine oil, turpentine, pine tar, charcoal and other blended solvents. In 1967, the Cabot portion of the site was sold to a local private investor, and approximately 10 years later it was developed into the existing shopping center. A release from a former Cabot process lagoon occurred during this period, resulting in impacts to nearby creeks.
After receiving complaints about these impacts local, state, and EPA investigations were conducted and corrective actions were implemented. In October 1981, EPA proposed the site for placement on the National Priorities List (NPL). NPL listing was finalized in 1983. Remedial investigations (RIs) were completed in 1987 and 1989, and a feasibility study (FS) was completed in May of 1990.
This project was a time-constrained remediation of impacted soils from 90 residential properties and required our client to obtain access/remediation agreements from every property owner for the project. The primary contaminants of concern were dioxin with some PAHs and arsenic. The tasks performed included initial site access and a ground survey, as well as land/plantscape plans to develop an approach that facilitated the removal of 1ft of impacted soils from the properties. Once a land/plantscape design was completed, our local tree clearing subcontractor shaped, limbed, cleared, chipped, and removed trees from the properties. Sevenson removed any old fencing and debris prior to self-performing contaminated excavation and backfill activities. Once the excavation and backfill was completed, our local landscape subcontractor restored the lawns (virtually all were sod), installed new plants and trees, and installed irrigation systems, as well as mulching and other landscaping improvements. Once landscaping was completed, our local fencing subcontractor installed new fencing as designed by the engineer and landscape architects.
Challenges that added to project complexity included:
- Property designs: Due to schedule constraints, excavation limits, tree clearing requirements (which had to be approved by City of Gainesville Arborist), and third-party landscape and fencing designs were being procured and performed as we progressed through the neighborhood in lieu of all designs being completed before we mobilized to the site
- The client desired to provide watering of completed landscaping (lawns and plants) for a period of 6 months post completion of each individual property. A water distribution system was developed by Sevenson to facilitate this requirement
- Coordinating with property owners to limit our impact on their daily lives (noise controls, access to homes, limited property destruction, etc.) as virtually all residents remained at their houses throughout remediation and construction
Scope areas Sevenson self-performed and managed also included:
- Completing Residential Remediation of 40,000 CY of impacted soils as well as debris and fencing on 90 residential properties
- Soil contaminants including primarily dioxin
- Initial site access and a ground survey, as well as land/plantscape plans to develop an approach that facilitated the removal of 1ft of impacted soils from the properties
- Transported impacted soils (1ft excavation) from residential properties to owner’s on-site consolidation area
- Restoration of impacted properties with 9 inches of fill and topped with 3 inches of topsoil