Okla. Admin. Code § 165:25-3-6.25

Current through Vol. 42, No. 8, January 2, 2025

Section 165:25-3-6.25 - Interstitial monitoring

(a) For double-walled underground storage tank systems, the sampling or testing method must be capable of detecting a leak at least every thirty (30 days) through the inner wall in any portion of the tank that routinely contains product in accordance with the manufacturer instructions.

(b) On new installations, the containment sumps used for interstitial monitoring of piping must be tested at installation by a licensed UST Installer or a licensed tester using a PSTD approved testing method that tests the sump above the highest penetration or sump sidewall seam. After initial testing, sumps must be tested at least once every three (3) years for liquid tightness by a licensed tester or use double-walled containment sumps with periodic interstitial monitoring of the space between the two (2) walls of the sump at least every thirty (30) days. Records demonstrating compliance must be maintained for three (3) years.

(c) Existing systems must have the containment sumps tested for liquid tightness by October 13, 2018, and at least once every three (3) years thereafter by a licensed tester or use double-walled containment sumps with periodic interstitial monitoring of the space between the two (2) walls of the sump at least every thirty (30) days. Owners and operators using a low liquid level test must ensure that when the sensor is activated the alarm activates, and verify the submersible pumps automatically shut off when the liquid activates the sensors. Sensors must be mounted and positioned at the lowest point in the sumps. Low liquid level UST sump testing must be performed according to the procedures set forth on the Commission's Containment Sump Alternative Test form. Records demonstrating compliance must be maintained for three (3) years.

(d) Beginning October 13, 2018, owners and operators must perform operation and maintenance tests on electronic and mechanical components of release detection equipment. This testing must be conducted according to the manufacturer's instructions or a code of practice developed by a nationally recognized association or independent testing laboratory. A test of the proper operation must be performed by a licensed tester at least annually and, at a minimum, as applicable to the facility, cover the following components and criteria:

(1) Automatic tank gauge and other controllers: test alarm, verify system configuration, test battery backup.

(2) Probes and sensors: inspect for residual buildup, ensure floats move freely, ensure shaft is not damaged, ensure cables are free of kinks and breaks, test alarm operability and communication with controller.

(3) Vacuum pumps and pressure gauges: ensure proper communication with sensors and controller.

(4) Hand-held electronic sampling equipment associated with groundwater and vapor monitoring: ensure proper operation.

(e) Owners and operators must maintain records of the annual operation tests for three (3) years. At a minimum, records must list each component tested, indicate whether each component meets the criteria listed above or needed to have action taken, and describe any action taken to correct an issue.

(f) Containment sumps and annual operation and maintenance tests on electronic and mechanical components of release detection equipment must be scheduled by submitting the PSTD scheduling form in the established online format and PSTD staff may be present.

Okla. Admin. Code § 165:25-3-6.25

Amended and renumbered from 165:25-3-5.5 at 23 Ok Reg 2261, eff 7-1-06; Amended at 25 Ok Reg 1867, eff 7-1-08

Amended by Oklahome Register, Volume 33, Issue 23, August 15, 2016, eff. 8/25/2016

Amended by Oklahoma Register, Volume 34, Issue 24, September 1, 2017, eff. 9/11/2017

Amended by Oklahoma Register, Volume 35, Issue 24, September 4, 2018, eff. 10/1/2018

Amended by Oklahoma Register, Volume 36, Issue 21, July 15, 2019, eff. 8/1/2019

Amended by Oklahoma Register, Volume 37, Issue 24, September 1, 2020, eff. 10/1/2020

Amended by Oklahoma Register, Volume 41, Issue 23, August 15, 2024, eff. 10/1/2024