40 CFR §96.83

1. (a)Applying for initial NOX Budget opt-in permit. In order to apply for an initial NOX Budget opt-in permit, the NOX authorized account representative of a unit qualified under § 96.80 may submit to the permitting authority at any time, except as provided under § 96.86(g):
   1. (1)A complete NOX Budget permit application under § 96.22;
   2. (2)A monitoring plan submitted in accordance with subpart H of this part; and
   3. (3)A complete account certificate of representation under § 96.13, if no NOX authorized account representative has been previously designated for the unit.
2. (b)Duty to reapply. The NOX authorized account representative of a NOX Budget opt-in source shall submit a complete NOX Budget permit application under § 96.22 to renew the NOX Budget opt-in permit in accordance with § 96.21(c) and, if applicable, an updated monitoring plan in accordance with subpart H of this part.