40 CFR §280.21

1. (a)Alternatives allowed. All existing UST systems must comply with one of the following requirements:
   1. (1)New UST system performance standards under § 280.20;
   2. (2)The upgrading requirements in paragraphs (b) through (d) of this section; or
   3. (3)Closure requirements under subpart G of this part, including applicable requirements for corrective action under subpart F of this part.
2. (b)Tank upgrading requirements. Steel tanks must be upgraded to meet one of the following requirements in accordance with a code of practice developed by a nationally recognized association or independent testing laboratory:
   1. (1)Interior lining. Tanks upgraded by internal lining must meet the following:
      1. (i)The lining was installed in accordance with the requirements of § 280.33; and
      2. (ii)Within 10 years after lining, and every 5 years thereafter, the lined tank is internally inspected and found to be structurally sound with the lining still performing in accordance with original design specifications. If the internal lining is no longer performing in accordance with original design specifications and cannot be repaired in accordance with a code of practice developed by a nationally recognized association or independent testing laboratory, then the lined tank must be permanently closed in accordance with subpart G of this part.
   2. (2)Cathodic protection. Tanks upgraded by cathodic protection must meet the requirements of § 280.20(a)(2)(ii), (iii), and (iv) and the integrity of the tank must have been ensured using one of the following methods:
      1. (i)The tank was internally inspected and assessed to ensure that the tank was structurally sound and free of corrosion holes prior to installing the cathodic protection system; or
      2. (ii)The tank had been installed for less than 10 years and is monitored monthly for releases in accordance with § 280.43(d) through (i); or
      3. (iii)The tank had been installed for less than 10 years and was assessed for corrosion holes by conducting two tightness tests that meet the requirements of § 280.43(c). The first tightness test must have been conducted prior to installing the cathodic protection system. The second tightness test must have been conducted between three and six months following the first operation of the cathodic protection system; or
      4. (iv)The tank was assessed for corrosion holes by a method that is determined by the implementing agency to prevent releases in a manner that is no less protective of human health and the environment than paragraphs (b)(2)(i) through (iii) of this section.
   3. (3)Internal lining combined with cathodic protection. Tanks upgraded by both internal lining and cathodic protection must meet the following:
      1. (i)The lining was installed in accordance with the requirements of § 280.33; and
      2. (ii)The cathodic protection system meets the requirements of § 280.20(a)(2)(ii), (iii), and (iv).
3. (c)Piping upgrading requirements. Metal piping that routinely contains regulated substances and is in contact with the ground must be cathodically protected in accordance with a code of practice developed by a nationally recognized association or independent testing laboratory and must meet the requirements of § 280.20(b)(2)(ii), (iii), and (iv).
4. (d)Spill and overfill prevention equipment. To prevent spilling and overfilling associated with product transfer to the UST system, all existing UST systems must comply with UST system spill and overfill prevention equipment requirements specified in § 280.20(c).