As used in this subchapter, unless the context otherwise requires:
(1) “Commission” means the Oil and Gas Commission.
(2) “Native gas” means gas which has not been previously withdrawn from the earth;
(3) “Natural gas” means gas either while in its original state or after the gas has been processed by removal therefrom of component parts not essential to its use for light and fuel;
(4) “Natural gas public utility” means any person, firm, or corporation authorized to do business in this state and engaged in the business of producing, transporting, or distributing natural gas by means of pipelines into, within, or through this state for ultimate public consumption; and
(5) “Underground storage” means storage in a subsurface stratum or formation of the earth;