"Commencement of construction" shall mean any substantial action, such as clearing of land, excavation or other action that reflects a substantially irreversible commitment to physically construct a facility, or that may affect the environment of a facility. The term does not include: site exploration, necessary roads for site exploration, borings to determine foundation conditions, or other preconstruction monitoring, or testing to establish background information related to the suitability of the site for the protection of environmental values.
132 Neb. Admin. Code, ch. 1, § 016