Karen's practice also focuses on the assessment and mitigation of subsurface vapor intrusion to indoor air. In this area, she applies her knowledge and experience in not only contaminant fate and transport, but also human health risk assessment. Her experience includes management of groundwater remediation projects using emerging remediation technologies. For example, she managed the design and installation of the first zero-valent iron permeable reactive barrier (ZVI PRB) at a Superfund site in New Hampshire under U.S. EPA's risk-sharing program. While managing this project, she also obtained EPA approval to use passive diffusion bag (PDB) samplers for PRB performance monitoring. U.S. EPA officials cited her demonstration of the PDB technology at this site as exemplary, and a case study of the project appears in the Interstate Technology and Regulatory Council (ITRC) guidance document for PDBs.
Karen has also conducted numerous risk assessments, many of which have been used to support the risk management, remediation, and redevelopment of brownfield properties. Among her projects is risk assessment at a former industrial property in Pennsylvania that has been converted to a recreational trails network, and numerous risk assessments in Ontario to support brownfield redevelopment and property transactions.