(a) This article describes the requirements for repairing or upgrading underground storage tank systems. Upgrades and repairs shall be properly conducted in accordance with this article and any additional manufacturer's specifications.

(b) Section 2661 describes the requirements for repairing underground storage tanks, piping, or other underground storage tank system components that have caused an unauthorized release as defined in sections 25294 and 25295 of the Health and Safety Code.

(c) Section 2662(b) describes upgrade requirements for underground storage tanks containing hazardous substances other than motor vehicle fuel. Sections 2662(c) and (d) describe upgrade requirements for all underground storage tanks containing motor vehicle fuel. Underground storage tanks which contain motor vehicle fuel and which are constructed of fiberglass, other non-corrosive materials, steel clad with fiberglass, or steel clad with other noncorrosive materials, are not required to comply with the requirements of section 2662(c), but are required to meet the requirements of section 2662(d).

(d) Section 2663 describes the requirements for upgrading or repairing tanks using interior lining.

(e) Section 2664 describes the requirements for upgrading tanks using bladder systems.

(f) Section 2665 describes the upgrade requirements for spill containers and overfill prevention equipment.

(g) Section 2666 describes the upgrade requirements for underground piping.

(h) Owners or operators shall meet the upgrade requirements for underground storage tanks, spill containers, overfill prevention equipment, underground piping, and under-dispenser containment or under-dispenser spill control or containment systems, as applicable.

(i) As a preventive measure, an owner or operator may upgrade any underground storage tank constructed of any material which is not under pressure and which contains motor vehicle fuel as specified in sections 2662(a), (c), and (e). Before upgrading in accordance with this subdivision, the owner or operator shall prove to the satisfaction of the local agency that the underground storage tank system has not caused an unauthorized release. If soil samples are taken, the owner or operator shall notify the local agency in advance of taking the samples.

(j) Owners or operators shall maintain records of repairs, linings, and upgrades that demonstrate compliance with the requirements of this article for the remaining operating life of the tank.

(k) Local agencies shall not approve a repair or upgrade unless it can be demonstrated that the underground storage tank system is structurally sound and the method of repair or upgrade will prevent unauthorized releases due to structural failure or corrosion during the operating life of the underground storage tank system.

(l) The materials used in the repair or upgrading process shall be applied in accordance with nationally recognized engineering practices.

(m) Materials used in repairs and upgrades shall be compatible with the underground storage tank system existing materials and shall not be subject to deterioration due to contact with the hazardous substances being stored.

(n) Steel underground storage tanks that exhibit corrosion during the course of repair or upgrade shall comply with the cathodic protection requirements of section 2635(a)(2).