Viggo is a Director in the firm’s Administrative Law Department where he maintains a diverse environmental and energy regulatory and litigation practice. In his regulatory practice, Viggo represents regional and national clients in complex energy and environmental permitting matters, including permitting of energy facilities before the New Hampshire Site Evaluation Committee, and assists clients in navigating, and complying with, the numerous State and federal environmental laws. Viggo has significant experience advising clients on matters of solid waste, hazardous waste, contaminated site management, wetland and shoreland matters, and emerging contaminants. He also assists clients in managing environmental risks and liabilities in commercial and real estate transactions.

Viggo focuses his litigation practice on environmental and energy-related litigation, including defending clients facing State and federal enforcement actions, defending complex environmental cases involving emerging contaminants such as PFAS, citizen suits, and private actions. Viggo also has experience with administrative litigation and has successfully challenged administrative rulemaking.  He routinely represents clients in environmental appeals before the four New Hampshire environmental appeal councils, before State and federal courts, and the New Hampshire Supreme Court.

Viggo received his J.D., cum laude, and Master of Energy Regulation and Law degree, magna cum laude, from Vermont Law School (2015). Since 2024, Viggo has served as the Chair of the Environmental and Natural Resources Section of the NH Bar Association. In his spare time, he can routinely be found skiing, hiking, running, rock climbing, fishing, and otherwise finding ways to enjoy the abundant access to the outdoors that New Hampshire has to offer.