When directed by the Department, the owner and operator of an underground storage tank system permanently closed before December 22, 1988, shall assess the excavation zone and close the underground storage tank system in accordance with this subchapter if the underground storage tank system is, in the judgment of the Department, posing a current or potential threat to human health and the environment.
25 Pa. Code § 245.454
This section cited in 25 Pa. Code § 245.422 (relating to upgrading of existing underground storage tank systems); 25 Pa. Code § 245.441 (relating to general requirements for underground storage tank systems); and 25 Pa. Code § 245.451 (relating to temporary removal from service (out-of-service)).