Removable, Sequestration Coatings for Mitigating Hazardous Contaminants Related to Deactivation and Decommissioning Activities

The Department of Energy (DOE)’s Oak Ridge Integrated Facility Disposition Project (IFDP) involves demolishing and upgrading infrastructure at the Y-12 Complex. Elemental mercury (Hg) and related species have been identified as high priority contaminants at Y-12. Strippable, fixative coatings with visual indication of contaminant capture can offer in-situ monitoring and characterization capabilities, source removal, improve safety, and minimize hazards and waste during the demolition process. Currently-used strippable coatings contain hazardous materials, do not provide visual indication and are not targeted for mercury-specific capture. This project is using an environmentally friendly coating formulation to capture and seal contaminants on the surface providing in-situ detection of Hg through color formation. The Hg- specific coatings are designed for selective and efficient capture of Hg species. The stripped coatings are targeted to minimize hazardous waste volumes, and disposal at a reduced cost. Phase II successfully established that the coatings show Hg-specific color, visible to the eye, in the presence of interferents. The coatings also captured very high quantities (17–247 µg/g of elemental, soluble and insoluble Hg-species) from soil and brick samples from the Y-12 site, confirmed by analysis of the stripped coating. Robotic application of the coating was demonstrated on 16 feet vertical walls. Small scale field trials conducted by the collaborator at a contaminated facility, indicated the coating captured 4 and 12 µg/g of Hg from two surfaces. In Phase IIB, the coating formulation will be optimized for Hg-capture and scaled-up for use with a robotic spray applicator. The technology demonstration will be accomplished by: (1) small scale field trials for in-situ detection and characterization of Hg-contaminated surfaces, (2) using robotics to remotely-apply the coating in a highly hazardous area at the Y-12 facility, (3) in-situ monitoring of coated areas, (4) analysis of the stripped coating for waste classification, and (5) assisting in on-site or off-site disposal considerations and application potential in remediation activities. An expanded product line can be utilized by DOE facilities, Department of Defense (DOD), Environmental Protection Agency (EPA), and commercial facilities in fixing and sealing mercury, lead and other toxic heavy metal contamination during remediation. Remediation and early in- situ contamination identification of industrial hazards are other benefits of this technology