Minnesota Administrative Rules

7150.0345 REPORTING, INVESTIGATING, AND CONFIRMING RELEASES.

Subpart 1.

Investigating and confirming.

A.

Owners and operators must immediately investigate, confirm, and remedy all suspected releases.

B.

Within 24 hours of discovering an unusual operating condition while conducting leak detection according to part 7150.0330 or 7150.0340, owners and operators must investigate the condition by:

(1)

conducting a visual inspection of aboveground and exposed below-grade components of a UST system for leaks and deficiencies; and

(2)

if applicable, repeating any leak test that indicated an unusual operating condition, conducted according to part 7150.0330, subpart 5, 6, or 6a, or 7150.0340, subpart 2, item A; 3, item B; or 4, item A.

C.

Upon discovering an unusual operating condition or confirming an unusual operating condition according to item B, subitem (2), owners and operators must initiate within 24 hours and complete within seven days the following:

(1)

tightness testing according to part 7150.0330, subpart 4, or 7150.0340, subpart 3, item A, on the component suspected of leaking; and

(2)

if applicable, integrity testing, using an agency-approved tester, of interstitial and secondary-containment areas used for leak detection.

D.

If the investigation under item B or the testing under item C indicates that the UST system is not leaking, owners and operators may resume leak testing the UST system according to part 7150.0300.

E.

If testing confirms a leak, owners and operators must immediately remove the regulated substance from the leaking component to prevent further releases and must repair, replace, upgrade, or permanently close the UST system.

Subp. 2.

Reporting releases or suspected releases.

A person who has knowledge of a release from a UST system under that person's control must immediately notify the Minnesota duty officer upon discovering the release by calling 1-800-422-0798 and must begin recovering the substance according to Minnesota Statutes, section 115.061. Notice under this subpart is also required if:

A.

the owners and operators discover a release of a regulated substance at the underground tank site or in the surrounding area;

B.

an unusual operating condition exists, unless:

(1)

the system component is immediately repaired or replaced; and

(2)

for secondarily contained systems, any liquid in the interstitial space not used for monitoring is immediately removed; or

C.

monitoring results from a release-detection method or alarm indicates a release may have occurred, unless:

(1)

the monitoring device or alarm is found to be defective and is immediately repaired, recalibrated, or replaced, and additional monitoring does not confirm the initial results;

(2)

the leak is contained in a secondary-containment space and:

(a)

any liquid in the secondary-containment space not used for monitoring is immediately removed; and

(b)

any defective system equipment or component is immediately repaired or replaced; or

(3)

the alarm is investigated and determined to be a nonrelease event.

Subp. 3.

Assessing site; permanent closure or status change.

A.

Before completing a tank or piping system closure according to part 7150.0410 or changing the status of storing a nonregulated substance, owners and operators must measure, by laboratory analysis, for the presence of a release.

B.

Sampling under item A must be according to the commissioner's requirements. The requirements must be based upon where contamination is most likely to be present, taking into consideration the method of closure, nature of the stored substance, type of backfill, depth to groundwater, and other factors relevant to identifying the presence of a release.

C.

If contaminated soils, contaminated groundwater, or free product as a liquid or vapor is discovered by measurement under this subpart or by any other means, the Minnesota duty officer must be immediately notified by calling 1-800-422-0798 and corrective action must be started according to Minnesota Statutes, section 115.061.

Statutory Authority:

MS s 116.49

History:

43 SR 1253

Published Electronically:

June 6, 2019