50 CFR §259.5

1. (a)Other than the maximum annual ceilings established by the Act, the Secretary shall not establish an annual ceiling. However, deposits can no longer be made once a party has deposited 100 percent of the anticipated cost of all Schedule B objectives unless the Agreement is then amended to establish additional Schedule B objectives.
2. (b)Ordinarily, the Secretary shall permit deposits to accumulate prior to commencement of any given Schedule B objective for a maximum of ten years. However, at the Secretary's sole discretion and based on good and sufficient cause shown, the time period may be extended.