The US Connecticut Department of Energy and Environmental Protection (DEEP), along with partners at the federal, municipal, and community levels, and the private sector, on 9 July announced completion of remediation activities at the former United Nuclear Corporation site in the Newhallville neighbourhood of New Haven.
The site was utilised by the US Department of Energy (DOE) to conduct research and make nuclear fuel components for the Navy from the mid-1950s until 1974, during the Cold War. Although environmental clean-up was conducted at the time the facility closed, the Nuclear Regulatory Commission (NRC) reviewed the situation in recent years and determined that additional work was needed. Final remediation work at the site began in October 2019 and concluded in late 2020.
The completion of remediation work at the site was an example of different stakeholders working together for a common purpose. DOE, NRC, DEEP, General Electric (GE), the Connecticut Department of Public Health (DPH), the City of New Haven, Newhallville community organisers, and the current site owner all played key roles in this accomplishment.
“This project represents what we’re all about at the Department of Energy and Environmental Protection, protecting the environment, and protecting the people who live in that environment,” DEEP Commissioner Katie Dykes said. “The Lamont Administration is committed to equity, to ensure that all communities get the same quality of clean-up and environmental remediation. I’m so grateful to all of the different agencies and stakeholders who made this project possible.”
DOE officials coordinated funding, and reviewed procedures and the work done on the project, while former site owner GE, facilitated the work.
“At General Electric, we are committed to ensuring that all communities where we operate realise the strongest environmental protection from our activities,” said James Van Nortwick, GE Project Manager. “Although we acquired UNC long after the New Haven facility had closed, and never operated there, we worked closely with a number of partners to achieve a single goal- successfully complete the remediation activities, and return the property for the benefit of the community.”
The final remediation work consisted of deconstructing the buildings on-site, as well as concrete foundations, utility trenches, and sub-slab structures and basins, and excavation of underlying soil to achieve acceptable regulatory requirements. Clean-up operations were conducted to minimise the generation of airborne dust, and air monitoring activities were conducted throughout the process. Nearly 10,000 tons of waste materials were removed from the site, and transported to facilities in Alabama and Utah without incident. Where possible, non-regulated construction debris, such as concrete and steel, was recycled locally. Deconstruction was conducted by Stamford Wrecking Company, with oversight by Arcadis, an environmental consulting firm.
Throughout the course of the remediation work, neighbourhood stakeholders were kept informed through project managers’ attendance at monthly community team meetings, and were provided status update emails and fact sheets that included photographs, air monitoring data, and information regarding waste shipments.
Radiation professionals from DEEP and the NRC provided oversight of the remediation work, reviewing work plans to ensure regulatory compliance; and conducting independent confirmatory analyses to confirm that the site was remediated to state and federal standards. These analyses included analysing numerous soil samples taken from the site and conducting a scan of the site using radiation detection instruments to ensure the soil met state and federal radiological criteria.
“Based on our review of documents, our inspections, the final site survey, and NRC ORISE confirmatory surveys, we have reasonable assurance the site meets the requirements for unrestricted use,” Diane Screnci, Senior Public Affairs Officer, NRC, said. “That means, from a radiological perspective, the owners or future owners of the site have no restrictions on what the land can be used for.”