(a) Initial referendum. The Order shall not become effective unless:

(1) The Secretary determines that the Order is consistent with and will effectuate the purposes of the Act; and

(2) The Order is approved by a majority of producers and importers voting for approval who also represent a majority of the volume of blueberries represented in the referendum who, during a representative period determined by the Secretary, have been engaged in the production or importation of blueberries.

(b) Subsequent referenda. Every five years, the Secretary shall hold a referendum to determine whether blueberry producers and importers favor the continuation of the Order. The Order shall continue if it is favored by a majority of producers and importers voting for approval who also represent a majority of the volume of blueberries represented in the referendum who, during a representative period determined by the Secretary, have been engaged in the production or importation of blueberries. The Secretary will also conduct a referendum if 10 percent or more of all eligible blueberry producers and importers request the Secretary to hold a referendum. In addition, the Secretary may hold a referendum at any time.