(2) In determining whether to grant an exemption pursuant to subsection (1) of this section, the commission shall consider:
(a) Protection of the health, safety and welfare of the citizens of this state;
(b) Feasibility and cost of noise abatement; and
(c) Past, present and projected patterns of land use and such state and local laws and regulations as are applicable thereto. [1977 c.511 §3]