Overview

• The EPA on Sept. 9 proposed guidance to redefine when construction 'begins' under New Source Review so firms can perform non‑emitting pre‑construction work before obtaining Clean Air Act permits.
• The policy targets infrastructure for data centers, power plants and manufacturing facilities, which under current NSR rules cannot start construction ahead of air permits.
• EPA officials said they intend to propose and finalize a formal rule in 2026 to codify the revised definition of 'begin actual construction.'
• Business groups praised the step for streamlining timelines, while some observers warned companies could face risks if they build early and state or local authorities later deny permits.
• The action fits into the administration’s Powering the Great American Comeback initiative and broader deregulatory push to expand energy supply for AI, following withdrawal of a prior NSR proposal.