(a) Each gas corporation shall be solely responsible for the inspection, testing, operation, maintenance, replacement and reconstruction of all mains, service lines, service connections and appurtenant facilities which it uses to supply gas to customers.
(b) The corporation shall bear the cost of inspecting, testing and operating all facilities. It shall bear the cost of maintaining, replacing or reconstructing all main and appurtenant facilities. It shall also bear the cost of maintaining, replacing or reconstructing the service line and appurtenant facilities necessary to serve each as if such customer were an applicant for service, unless an act or ommission of the customer necessitates the replacement or reconstruction.
(c) If an act or omission of any customer who had installed facilities necessitates the replacement or reconstruction of such facilities, the customer shall pay to the corporation the cost of replacement or reconstruction.