Sec. 5. "Air pollution", for purposes of air pollution control laws and environmental management laws, means the presence in or the threatened discharge into the atmosphere of one (1) or more contaminants in sufficient quantities and of the characteristics and duration that:
(1) is injurious to or threatens to be injurious to human health, plant or animal life, or property; or
(2) interferes unreasonably with the enjoyment of life or property.