On or after January 26, 2005, an owner and an operator of a UST system shall install, upgrade, or replace piping that routinely contains petroleum vapor or a regulated substance in accordance with the following requirements: Install piping in a UL listed or Department approved secondary containment system that: Contains the petroleum vapor or regulated substance released from the primary piping until the petroleum vapor or regulated substance is detected and removed; Prevents a spill, release, or discharge of petroleum vapor or a regulated substance to the environment; and With the exception of the vent riser, beginning June 13, 2022, terminates or connects in a liquid tight containment sump with a sump sensor: Installed within 1 inch of the lowest part of the sump bottom; Properly secured in the sump by a fixed mounting bracket; and That activates an alarm when liquid is detected; Connect piping to the UST in a liquid tight containment sump that is maintained clean and free of liquid; When a product dispenser is part of the UST system, install piping that terminates in an under-dispenser containment sump that is liquid tight and maintained clean and free of liquid; and If an intermediate sump is used, connect piping in a liquid tight containment sump that is maintained clean and free of liquid. Corrosion Protection Standards for Piping. An owner and an operator of a UST system shall ensure that piping in contact with the ground, including soil and backfill material, or continuous or intermittent water, is properly designed, constructed, and protected from corrosion in accordance with one of the following methods: The piping and connectors are constructed of fiberglass-reinforced plastic or flexible piping that is UL listed as appropriate piping for the regulated substance stored and for use in a UST system; The piping is constructed of steel, is coated with a suitable dielectric material, and has a cathodic protection system designed by a corrosion expert; or Subject to the approval of the Department, the piping is constructed and protected from corrosion by an alternative installation method that is designed to prevent a spill, release, or discharge or a threatened spill, release, or discharge of a stored regulated substance in a manner determined by the Department to be as protective of public health, safety, and welfare and the environment as the types of piping described in §B(1)(a) and (b) of this regulation. An owner and an operator of a UST system with steel piping equipped with a cathodic protection system installed in accordance with §B(1)(b) of this regulation shall: Operate and maintain the piping cathodic protection system in accordance with COMAR 26.10.04.02; and If the piping cathodic protection system is an impressed current system, ensure the impressed current system is designed to allow for the determination of the current operating status as required in COMAR 26.10.04.02. An owner and an operator of a UST system may not use a fiberglass-reinforced plastic piping system: For direct fill lines, unless approved by the Department; or Aboveground or above grade. After January 1, 2009, an owner and an operator that installs a new, upgraded, or replacement UST system may not use a flexible piping system for: Direct fill lines; Vent lines; or Stage II vapor recovery lines. An owner and an operator of a UST system that replaces 40 percent or more of piping connected to a single UST, including each independent piping run connected to a UST with multiple piping runs, shall replace the remaining single-walled piping connected to the UST with a piping system that meets the requirements of this regulation.