The Board of Commissioners may call a special meeting of the District when it deems it necessary or prudent to do so, and shall call a special meeting of the District when action by the voters of the District is necessary under this chapter or under any applicable law. In addition, the Board of Commissioners shall call a special meeting of the District if petitioned to do so by not less than five percent of the legal voters of the District. The Board of Commissioners may rescind the call of a special meeting called by it but not a special meeting called on application of five percent of the legal voters of the District.