Owners and operators of UST systems with internal linings used to meet the upgrade requirements in WAC 173-360A-0320 (2)(a)(i) must comply with the requirements of this section.

(1) Inspections. Within ten years after lining and every five years thereafter, lined tanks must be internally inspected to determine whether the tanks remain structurally sound and the linings are still performing in accordance with the original design specifications. Internal inspections must be performed:

(a) By or under the direct supervision of a service provider certified in accordance with Part 9 of this chapter; and

(b) In accordance with a code of practice. The following codes of practice may be used to meet this requirement:

(i) American Petroleum Institute, Recommended Practice 1631, "Interior Lining and Periodic Inspection of Underground Storage Tanks";

(ii) National Leak Prevention Association, Standard 631, Chapter B, "Future Internal Inspection Requirements for Lined Tanks"; or

(iii) Ken Wilcox Associates, Recommended Practice, "Recommended Practice for Inspecting Buried Lined Steel Tanks Using a Video Camera."

(2) Repairs.

(a) Following invasive internal inspections, tanks must be repaired and tightness tested in accordance with WAC 173-360A-0490.

(b) Lined tanks failing an internal inspection must be repaired and tightness tested in accordance with WAC 173-360A-0490. Lined tanks that cannot be repaired in accordance with a code of practice must be permanently closed in accordance with WAC 173-360A-0810.

(3) Reporting. Internal inspections of lined tanks must be reported to the department within thirty days using the applicable checklist provided by the department. The checklist must be completed by the service provider.

(4) Recordkeeping. Records of internal inspections of lined tanks must be maintained until the UST system is permanently closed or undergoes a change-in-service.