38 C.F.R. § 26.70
(a) Programmatic NEPA documents allow VA to conduct broad or holistic evaluations of effects or policy alternatives, evaluate widely applicable measures, or avoid duplicative analysis by considering all or some of the environmental effects of a policy, program, plan, group of projects or related types of projects, national or regional actions, or otherwise related actions. Programmatic NEPA documents support efficiency of NEPA review at the site-, action-, and project-specific level. VA may evaluate the proposal(s) in one of the following ways:
(d) VA may prepare a NEPA analysis specific to a unique program or project that has aspects different from or not sufficiently evaluated within a larger programmatic analysis. To tier an analysis to a previous programmatic EIS or EA, VA must: