Ariz. Admin. Code § R18-12-251 - Suspected Releases; Secondary Containment Leaks

A. 24 hour notifications. An owner or operator shall notify the Department, within 24 hours of either of the following:

1. Discovery of a suspected release, except for:

1 a. A spill or overfill of 25 gallons or less of petroleum, or a hazardous substance that is less than its reportable quantity under CERCLA, contained and cleaned up within 24 hours, or

2. The conditions described in A.R.S. § 49-1001(16)(b) or (c)(i) exist for 24 hours or less.

b. Monitoring results, including investigation of an alarm, from a release detection method required under R18-12-241, R18-12-242 or R18-12-243(G) that indicate a release may have occurred if one of the following is true:

i. The monitoring device is found to be defective, and is immediately repaired, recalibrated or replaced, and additional monitoring does not confirm the initial result; or

ii. The leak is contained in the secondary containment and:

(1) Except as provided for in R18-12-243(G)(2)(d), any liquid in the interstitial space not used as part of the interstitial monitoring method (for example, brine filled) is immediately removed, and

(2) Any defective system equipment or component is immediately repaired or replaced; or

iii. In the case of inventory control described in R18-8-243(A), a second month of data does not confirm the initial result or the investigation determines no release has occurred; or

iv. The alarm was investigated and determined to be a non-release event (for example, from a power surge or caused by filling the tank during release detection testing).

2. Discovery of liquid in the interstitial space of secondarily contained systems unless the leak is contained in the secondary containment and all of the following are true:

a. The system equipment or component is found not to be releasing regulated substances to the environment;

b. Any defective system equipment or component is immediately repaired or replaced; and

c. For secondarily contained systems, except as provided for in R18-12-243(G)(2)(d), any liquid in the interstitial space not used as part of the interstitial monitoring method (for example, brine filled) is immediately removed.

B. 24 hour notification content. The notification shall identify the:

1. Individual notifying the Department;

2. UST involved and the reason for notifying the Department;

3. Facility involved;

4. Owner and the operator of the UST facility; and

5. Investigation and containment actions taken as of the date of the notification.

C. Requirement to investigate suspected releases. Within 60 calendar days from the suspected release discovery date or the suspected release notification date, whichever is earlier, an owner or operator shall complete the investigation requirements of this subsection and confirm whether the suspected release is a release. The investigation shall include:

1. Tightness tests of the tank and all connected piping meeting the requirements of R18-12-243(C) and R18-12-244(B), or, as appropriate, secondary containment testing as described in R18-12-233(B) . The tests shall determine whether a leak exists in that portion of the tank that routinely contains product, or the attached delivery piping, or whether a breach of either wall of the secondary containment has occurred. Further investigation is required if the results of the tightness tests indicate that the system is either not tight or contaminated media is the basis for suspecting a release.

2. If further investigation is required under subsection (1), a site check meeting the requirements of this subsection shall be performed. The owner or operator shall measure for the presence of a release where contamination is likely to be present and shall consider:

a. The nature of the regulated substance;

b. The type of initial alarm or cause for suspicion;

c. The type of backfill;

d. The depth to groundwater; and

e. Other factors appropriate for identifying the presence and source of the release.

D. Interstice Leak or Release Confirmation. If the testing confirms a leak into the interstice or a release, the owner or operator shall repair, replace, upgrade or close the UST system. In addition, if a release is confirmed, the owner or operator shall notify the Department as required by R18-12-260(A), cease further compliance with this Section, and perform corrective actions under R18-12-260 through R18-12-264.01

E. 14 day report. The owner or operator shall submit a written status report, on a form provided by the Department, within 14 calendar days after the suspected release discovery date or the suspected release notification date, whichever is earlier. If the suspected release is confirmed to be a release within the 14 day period, the 14 day report is satisfied when the report required by R18-12-260(C) is submitted. If known on the date the 14 day report is submitted, an owner or operator shall identify the:

1. UST that is the source of the suspected release;

2. Nature of the suspected release;

3. Regulated substance suspected to be released; and

4. Initial response to the suspected release.

F. 90 day report. If the suspected release is not confirmed to be a release the owner or operator shall submit a written report, on a form provided by the Department, within 90 calendar days after the suspected release discovery date or suspected release notification date, whichever is earlier, showing that the investigation has been completed and a release does not exist. Unless previously submitted, the 90 day report shall identify the:

1. UST suspected to be the source of the release;

2. Nature of the suspected release;

3. Regulated substance suspected to be released;

4. Response to the suspected release;

5. Repair, recalibration, or replacement of a monthly monitoring device described in R18-12-243(D) through (H) or R18-12-244(C), and any repair or replacement of faulty UST system equipment, including any piping, that may have been the cause of the suspected release;

6. Results of any tightness test conducted under subsection (C)(1);

7. Person, if the site check described in subsection (C)(2) was not performed, having direct knowledge of the circumstances of the suspected release who observed contaminated media during the discovery or investigation.

8. Laboratory analytical results on samples collected during the site check described in subsection (C)(2); and

9. Site plan showing the location of the suspected release and site check sample collection locations.

G. Investigation of suspected releases required by the Department. If the Department becomes aware of an on- or off-site impact of a regulated substance, the owner or operator shall be notified and may be required, based on an assessment of site specific information, to perform an investigation under subsection (C). If an investigation is required, the Department shall describe the type of impact and the rationale for its decision that the UST system may be the source of the impact.

Notes

Ariz. Admin. Code § R18-12-251

New Section made by final rulemaking at 8 A.A.R. 3894, effective August 20, 2002 (Supp. 02-3). Amended by final rulemaking at 25 A.A.R. 3123, effective 1/1/2020.