1. (i) When a UST system is out-of-service, the facility must continue operation and maintenance of corrosion protection in accordance with section 613-2.2(b) of this Subpart, and any leak detection in accordance with section 613-2.3(a) and (b) of this Subpart. Subpart 613-6 of this Part must be complied with if a release is confirmed.
2. (ii) Leak detection required under section 613-2.3(a) and (b) of this Subpart is not required as long as the UST system is empty. (The UST system is considered empty when all materials have been removed using commonly employed practices so that no more than 2.5 centimeters [one inch] of residue remain in the system.) However, leak detection required under section 613-2.3(a) and (b) of this Subpart must resume upon resumption of delivery of petroleum into the UST system.

3. (2) When a UST system is out-of-service for a period of 3 to 12 months, the facility must also comply with the following requirements:

   1. (i) leave vent lines open and functioning; and
   2. (ii) cap and secure all other piping, ancillary equipment, and manways.

4. (3) When a UST system is out-of-service for more than 12 months, the facility must permanently close the UST system in accordance with subdivisions (b) through (e) of this section.

   (b) Permanent closure and changes in service.

5. (1) At least 30 days before beginning permanent closure or a change in service, a facility must notify the department of its intent to permanently close or make the change in service, unless such action is in response to corrective action. The required assessment of the excavation zone under subdivision (c) of this section must be performed after notifying the department but before completion of the permanent closure or a change in service. The resultant report must be submitted to the department within 90 days after permanent closure. Within 30 days after permanent closure or a change in service, a facility must submit a registration application to the department, in accordance with section 613-1.9(f) of this Part, indicating that the UST system has been permanently closed or that a change in service has occurred.

6. (2) To permanently close a UST system:

   1. (i) The facility must empty and clean it by removing all liquids and accumulated sludge. Every tank that is part of a UST system that is permanently closed must also be either removed from the ground or filled with an inert solid material (such as sand or concrete slurry). If an inert solid material is used, all voids within the UST must be filled. All connecting and fill lines must be disconnected and removed or securely capped or plugged. Manways must be securely fastened in place.
   2. (ii) The facility must ensure that all scheduled deliveries to the UST system are terminated.
7. (3) Use of a UST system to store a substance other than petroleum is considered a change in service. Before a change in service, the facility must empty and clean the UST by removing all liquid and accumulated sludge and conduct a site assessment in accordance with subdivision (c) of this section.

8. (4) One of the following codes of practice (refer to section 613-1.10 of this Part for complete citation of references) must be adhered to in order to comply with this subdivision:

   1. (i) API RP 1604, March 1996;
   2. (ii) API RP 2016, August 2001;
   3. (iii) API RP 1631, June 2001; or

   4. (iv) NFPA 326, 2010 edition.

      (c) Assessing the site at closure or change in service.

9. (1) Before permanent closure or a change in service is completed, the facility must measure for the presence of a release where contamination is most likely to be present at the UST system location. In selecting sample types, sample locations, and measurement methods, the facility must consider the method of closure, the petroleum stored, the type of backfill, the depth to groundwater, and other factors appropriate for identifying the presence of a release. The requirements of this subdivision are satisfied if one of the external release detection methods allowed in section 613-2.3(c)(5) and (6) of this Subpart is operating in accordance with the requirements in section 613-2.3 of this Subpart at the time of closure, and indicates no release has occurred.
10. (2) If contaminated soils, contaminated groundwater, or petroleum as a liquid or vapor is discovered, the facility must begin corrective action in accordance with Subpart 613-6 of this Part.

11. (d) For any UST system that has been out-of-service since December 27, 1986 and was not properly permanently closed pursuant to department regulations governing UST system closure, the facility owner must assess the excavation zone and permanently close the UST system in accordance with this section if the department determines there is a potential for a release of petroleum from the UST system.

    (e) Records for permanent closure or change in service.

    The facility must maintain for three years records that are capable of demonstrating compliance with closure requirements under this Subpart. In addition, the facility must transmit a copy of the records to the department within 30 days after permanent closure or change in service.

(a) Out-of-service UST systems.

(1)