18 CFR §4.40

1. (a)Applicability. The provisions of this subpart apply to any application for an initial license for a major unconstructed project that would have a total installed capacity of more than 10 megawatts, and any application for an initial or new license for a major modified project with a total installed capacity more than 10 megawatts. An applicant for license for any major unconstructed or major modified water power project that would have a total installed generating capacity of 10 megawatts or less must submit application under subpart G of this part (§§ 4.60 and 4.61).
2. (b)Guidance from Commission staff. A prospective applicant for a license for a major unconstructed project or major modified project may seek advice from the Commission's Office of Energy Projects regarding the applicability of this subpart to its project [see § 4.32(h)], including the determinations whether any proposed repair, modification or reconstruction of an existing dam would result in a significant change in the normal maximum surface elevation of an existing impoundment, or whether any proposed change in existing project works or operation would result in a significant environmental impact.