TerraPower officials said last week to expect “dirt moving” at its Wyoming site come June—and for operations to begin there as early as 2030—as it advances plans to build new nuclear in the United States. But 40-plus pages of initial commentary from the Nuclear Regulatory Commission, in the form of a preapplication readiness assessment report, may slow TerraPower’s plans.

TerraPower, the advanced nuclear company backed by Bill Gates, announced last week that the start date for its Natrium reactor has been pushed back. As Russia is currently the only commercial source of the high-assay low- enriched uranium (HALEU) the plant requires, the company faces a lack of fuel availability. TerraPower originally planned to use Russian fuel to get its demonstration reactor up and running by 2028, but Russia’s invasion of Ukraine has dashed those plans.