Henry W. Killeen III is Of Counsel at Conn Maciel Carey LLP.
Henry has five decades of environmental law experience, advising clients across the full spectrum of federal and state environmental statutes on compliance, enforcement response, permitting, and complex litigation. He began his practice in the 1970s, playing a role in one of the most pivotal environmental cases in U.S. history: representing Occidental Petroleum in its response to contamination at the Love Canal in Niagara Falls, New York – an event that helped propel hazardous waste regulation into the national spotlight. His work since has continued to address high-stakes challenges involving hazardous waste site remediation under federal and state law.
Over the course of his career, Henry has handled matters involving PCB cleanup and regulatory compliance, hazardous air pollutant permitting and enforcement, stormwater management permitting, and other environmental regulatory frameworks. He also served as lead counsel in what was, at the time, the largest federal environmental crimes prosecution in the United States, reflecting his capability in high-exposure enforcement actions.
Beyond environmental law, Henry’s background includes litigation and related regulatory work, and his practice has spanned multiple complementary disciplines, including environmental, litigation, First Amendment, and general practice. He holds an AV Preeminent peer rating from Martindale‑Hubbell, the organization’s highest designation.
As Of Counsel, Henry applies his extensive experience to support clients navigating OSHA-related environmental issues, investigations, and regulatory compliance. His long perspective on the evolution of U.S. environmental law positions him as a valued advisor on matters where environmental and workplace safety regulation intersect.
- University of Buffalo, J.D.
- Harvard University, A.B.
