When a train partially derailed and impacted a Central Ohio Transit Authority (COTA) maintenance facility, Trihydro supported response efforts and soil remediation in coordination with United States Environmental Protection Agency (USEPA) requirements.

One of Central Ohio Transit Authority’s (COTA’s) maintenance facilities was impacted when a train carrying vegetable oils, ethanol, and other agricultural products partially derailed causing a spill and a fire. During response efforts and cleanup in the aftermath of the spill, buried drums were discovered that likely dated back to industrial use prior to COTA occupying the site. Soil and groundwater investigations to delineate the impact of the spill concluded that polychlorinated biphenyl (PCB) concentrations related to the buried drums were detected on the site. Removal of the PCB waste was recommended under the Toxic Substances Control Act (TSCA). The United States Environmental Protection Agency (USEPA) retains primacy over TSCA remediation and cleanup, so regulatory control for the site was transferred to USEPA from the Ohio EPA.

Following discussions with USEPA, COTA submitted a “Notification of Self-Implementing Cleanup of Polychlorinated Biphenyl (PCB) Contaminated Soil Remediation Work Plan” to USEPA Region V. The Work Plan outlined the anticipated characterization to delineate the extent of PCB contamination and the proposed excavation activities. The site was a commercial facility located in a commercial/industrial area. The remediated area was less than 0.25 acres in an unoccupied area outside of the bus maintenance facility and was a “low occupancy area.” The material remaining on site could be considered “existing piles of soil [and] in situ soil,” which meets the PCB remediation waste definition for the bulk PCB remediation waste class. For low occupancy, bulk remediation waste sites, the standards presented in 40 CFR 761, Subpart O governs completion of the self-implementing cleanup. For sites with a soil concentration of less than or equal to 25 milligrams per kilogram (mg/kg) of PCBs (≤25 parts per million [ppm]), an institutional control (i.e., a deed restriction) and post-excavation confirmatory sampling are necessary. 

The USEPA approved the Work Plan and requested an initial cleanup goal of ≤1ppm, which would allow unrestricted closure of the site. Following initial site characterization activities, a cleanup level of ≤25ppm was requested to limit the excavation extent and additional investigation costs. This cleanup level required a deed restriction limiting the site to low-occupancy industrial use (its current use), which the USEPA approved.

The additional investigation was completed in one month and the excavation was performed over one week. Areas with PCB concentrations greater than 25 ppm were excavated and no surficial soils in the area exceeded the Ohio VAP Direct Contact level of 18 ppm. Since PCB concentrations in the site soil remained at levels ≤25 ppm, a deed restriction was recorded, and a Cleanup Completion Report was submitted to USEPA.

Years later, COTA began plans for constructing a compressed natural gas (CNG) fueling station at this facility. General maintenance and use would involve personnel accessing a portion of the deed-restricted area and require the deed restriction in this area to be removed by achieving a cleanup level of less than or equal to 1 ppm to allow for unrestricted land use in a high occupancy setting.  

Over a span of three months, additional investigation activities were performed during pre-construction of the CNG facility to assist with soil management surrounding the facility during construction. As part of pre-construction activities, additional initial delineation activities were performed around the formerly excavated area to determine the extent to which the area would need to be further excavated to the more stringent cleanup level of 1 ppm. 

Following discussions with USEPA, COTA submitted an “Amended Notification of Self-Implementing Cleanup of Polychlorinated Biphenyl (PCB) Contaminated Soil Remediation Work Plan” to USEPA Region V. The Work Plan outlined the anticipated additional characterization activities, excavation and site cleanup verification activities, reporting requirements and notification, and certification requirements. The USEPA approved the Amended Work Plan with a cleanup goal of ≤1 ppm to remove a portion of the deed-restricted area.

In summary, approximately 2,000 tons of additional soil were excavated. Since the remediation cleanup goal was established at ≤1 ppm, the portion of the site within the fence is available for unrestricted general use. Some areas could not be excavated due to access issues and an institutional control remained over this small, inaccessible area of the site. 

“Trihydro has been a great addition to the COTA Team over the past 15 years. Working with Trihydro truly feels like a partnership. Whatever the circumstance is, we are in it together to resolve the environmental task at hand. It is always about doing the right thing, which makes us always on the same page. I have learned so much from Trihydro teammates over the years and look forward to working with them for many years to come.”

-Tim Smith, Director of Facilities, Central Ohio Transit Authority

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