Comment submitted by Sidley Austin LLP

Summary: Sidley Austin LLP, representing a client in the data center development industry, supports the EPA's proposed redefinition of "begin actual construction" in the New Source Review (NSR) program. They argue that the EPA should further clarify that non-emitting infrastructure, such as concrete pads for backup power and natural gas delivery systems, should be allowed for construction before a permit is issued because they do not emit pollutants or predetermine permit outcomes.