Owners and operators of temporarily closed UST systems must comply with the requirements of this section.

(1) Taking UST systems out of operation. Within thirty days of temporarily closing an UST system:

(a) The department must be notified using the applicable form provided by the department; and

(b) If the UST system will be temporarily closed for more than ninety days, the following actions must be completed and reported to the department on the form:

(i) Ensure vent lines are open and functioning;

(ii) Cap or secure all other lines, pumps, entryways, and ancillary equipment;

(iii) Empty the UST system in accordance with subsection (2) of this section, or measure the amount of regulated substances remaining in the system; and

(iv) If no UST systems are in operation at the UST facility, return the facility compliance tag to the department.

(2) Emptying temporarily closed UST systems. When emptying a temporarily closed UST system:

(a) All materials must be removed from the UST system using commonly employed practices. The remaining residue in the tanks must not exceed 2.54 centimeters (one inch); and

(b) The department must be notified in writing within thirty days. The notice must include documentation that the UST system has been emptied, such as an invoice. This notice may be combined with the notice required under subsection (1) of this section.

(3) Maintaining compliance during temporary closure. Except as otherwise provided in this subsection, owners and operators must comply with all of the applicable requirements of this chapter during temporary closure, including maintenance of corrosion protection and payment of annual tank fees.

(a) Spill and overfill prevention. The following tests and inspections of spill and overfill prevention equipment may be suspended during temporary closure, regardless of whether the UST system is emptied in accordance with subsection (2) of this section:

(i) Walkthrough inspections of spill prevention equipment (WAC 173-360A-0420);

(ii) Monitoring and tightness tests of spill prevention equipment (WAC 173-360A-0460); and

(iii) Inspections of overfill prevention equipment (WAC 173-360A-0470).

(b) Release detection and containment. Release detection in Part 6 of this chapter and the following tests and inspections of release detection equipment and containment may be suspended during temporary closure if an UST system is emptied in accordance with subsection (2) of this section:

(i) Walkthrough inspections of release detection equipment, containment sumps, and hydrant pits and vaults (WAC 173-360A-0420);

(ii) Monitoring and tightness tests of containment sumps used for interstitial monitoring (WAC 173-360A-0450); and

(iii) Tests of release detection equipment (WAC 173-360A-0480).

(c) Financial responsibility. Financial responsibility in Part 10 of this chapter may be suspended during temporary closure if:

(i) The UST system is emptied in accordance with subsection (2) of this section; and

(ii) After the UST system is emptied, a site assessment around the UST system is completed and reported in accordance with WAC 173-360A-0730. Unless otherwise directed by the department, a site assessment is not required if:

(A) A release from the UST system had previously been confirmed and reported to the department; and

(B) Further remedial action is necessary to investigate or clean up the confirmed release under WAC 173-360A-0750(4).

(4) Permanent closure of substandard UST systems. An UST system must be permanently closed within twelve months of temporary closure if the tanks or piping do not meet the applicable performance standards or upgrade requirements in Part 3 of this chapter, unless:

(a) A site assessment is performed around the UST system in accordance with WAC 173-360A-0730. Unless otherwise directed by the department, a site assessment is not required if:

(i) A release from the UST system had previously been confirmed and reported to the department; and

(ii) Further remedial action is necessary to investigate or clean up the confirmed release under WAC 173-360A-0750(4); and

(b) The department provides an extension of the twelve-month period. Requests for extensions must be submitted to the department in writing after the site assessment is completed.

(5) Returning UST systems to operation.

(a) Requirements for all temporarily closed UST systems. Before returning an UST system to operation, owners and operators must comply with all of the applicable requirements of this chapter, including any suspended during temporary closure under subsection (3) of this section. If financial responsibility is suspended during temporary closure, the owner or operator must demonstrate financial responsibility in accordance with WAC 173-360A-1045 (1)(a) or (b), as applicable, before returning an UST system to operation.

(b) Additional requirements for UST systems temporarily closed more than ninety days. When an UST system is temporarily closed for more than ninety days, owners and operators must also comply with the following additional requirements.

(i) Tests and inspections. Before returning an UST system to operation, the following tests and inspections, as applicable, must be completed to ensure the UST system is operating properly and will prevent releases to the environment.

(A) Tanks and piping. If release detection is suspended during temporary closure, tightness tests of tanks and piping must be performed in accordance with WAC 173-360A-0635 and 173-360A-0650. This requirement does not apply to suction piping meeting the standards in WAC 173-360A-0600 (1)(b)(i) through (v). The department must authorize any delivery or deposit of regulated substances needed to perform the tightness tests. To obtain such authorization:

(I) A preliminary evaluation of the tanks (such as a pressure decay test) must be performed; and

(II) A request must be submitted to the department using the applicable form provided by the department. The results of the preliminary evaluation must be included with the request.

(B) Spill and overfill prevention equipment. If suspended during temporary closure, the following tests and inspections of spill and overfill prevention equipment must be performed:

(I) Walkthrough inspections of spill prevention equipment (WAC 173-360A-0420);

(II) Monitoring or tightness tests of spill prevention equipment (WAC 173-360A-0460); and

(III) Inspections of overfill prevention equipment (WAC 173-360A-0470).

(C) Release detection equipment and containment. If suspended during temporary closure, the following tests and inspections of release detection equipment and containment must be performed:

(I) Walkthrough inspections of release detection equipment, containment sumps, and hydrant pits and vaults (WAC 173-360A-0420);

(II) Monitoring or tightness tests of containment sumps used for interstitial monitoring (WAC 173-360A-0450); and

(III) Tests of release detection equipment (WAC 173-360A-0480).

(ii) Notification of return to operation. Within thirty days of returning an UST system to operation, the department must be notified using the applicable form provided by the department. The completed checklists of any UST system services required to return the UST system to operation must be included with the notification form.

(c) Reissuance of facility compliance tag. If the facility compliance tag for an UST facility is returned to the department under subsection (1)(b)(iv) of this section, the department will reissue a facility compliance tag upon receipt of the completed notification form required under (b)(ii) of this subsection.