10 CFR §51.72

1. (a)The NRC staff will prepare a supplement to a draft environmental impact statement for which a notice of availability has been published in the Federal Register as provided in § 51.117, if:
   1. (1)There are substantial changes in the proposed action that are relevant to environmental concerns; or
   2. (2)There are significant new circumstances or information relevant to environmental concerns and bearing on the proposed action or its impacts.
2. (b)The NRC staff may prepare a supplement to a draft environmental impact statement when, in its opinion, preparation of a supplement will further the purposes of NEPA.
3. (c)The supplement to a draft environmental impact statement will be prepared and noticed in the same manner as the draft environmental impact statement except that a scoping process need not be used.