In determining whether this chapter is approved by vintners, the director must find that at least 40 percent of the total number of vintners from the list established by the director participated in the referendum, and that either one of the following has occurred:
(a)
Sixty-five percent or more of the vintners who voted in the referendum voted in favor of this chapter, and the vintners so voting either acquired or processed their own production, or a combination thereof, which represents a majority of the volume of winegrapes in the preceding marketing season, or in the current marketing season if the harvest is completed prior to the vote, by all the vintners who voted in the referendum.
(b)
A majority of the vintners who voted in the referendum voted in favor of this chapter, and the vintners so voting either acquired or processed their own production, or a combination thereof, which represents 65 percent or more of the volume of winegrapes in the preceding marketing season, or in the current marketing season if the harvest is completed prior to the vote, by all the vintners who voted in the referendum.