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Underground Storage Tanks (USTs)

Operating And Maintaining UST Systems - 2015 Requirements

In 2015, EPA revised the underground storage tank (UST) regulations. Below you will find the requirements for inspections and testing.

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Walkthrough Inspections

Beginning on October 13, 2018 owners and operators must conduct walkthrough inspections at their UST facility. The walkthrough inspection must meet one of the following:

Option 1: Every 30 days (except spill prevention equipment at UST systems receiving deliveries at intervals greater than every 30 days may be checked prior to each delivery), check your spill prevention equipment and release detection equipment. Annually, check your containment sumps and any hand held release detection equipment.

When conducting the walkthrough inspection, check the following:

  • Spill prevention equipment
    • Check for damage
    • Remove any liquid or debris
    • Check for and remove any obstructions in the fill pipe
    • Check the fill cap to make sure it is securely on the fill pipe
    • Double walled spill prevention equipment with interstitial monitoring check for a leak in the interstitial area
  • Release detection equipment
    • Ensure it is operating with no alarms or other unusual operating conditions present
    • Ensure records of release detection testing are reviewed and current
  • Containment sumps
    • Check for damage, leaks into the containment area, or releases to the environment
    • Remove any liquid or debris
    • Double walled containment sumps with interstitial monitoring check for a leak in the interstitial area
  • Hand held release detection equipment (for example tank gauge sticks or groundwater bailers)
    • Check for operability and serviceability

Option 2: Conduct walkthrough inspections according to a standard code of practice developed by a nationally recognized association or independent testing laboratory. The code of practice must check equipment comparable to option 1 above.

Option 3: Conduct walkthrough inspections according to requirements developed by your implementing agency. These requirements must be comparable to the requirements described in option 1 above.

In addition to these requirements, owners and operators must inspect the following additional areas for airport hydrant systems at least once every 30 days if confined space entry according to the Occupational Safety and Health Administration is not required or at least annually if confined space entry is required.

  • Hydrant pits – Check for any damage; remove any liquid or debris; and check for any leaks
  • Hydrant piping vaults – Check for any hydrant piping leaks

Owners and operators must maintain the most recent year’s walkthrough inspection records. Records need to include a list of each area checked, whether each area checked was acceptable or needed action taken, a description of any actions taken to correct issues, and delivery records if spill prevention equipment is checked less frequently than every 30 days due to infrequent deliveries.

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Overfill Prevention Equipment Inspections

Beginning on October 13, 2018 owners and operators must have their overfill prevention equipment inspected for proper operation at least once every three years. Overfill prevention equipment installed after October 13, 2015 must be inspected for proper operation at installation and then once every three years. Note that most installation codes of practice require inspecting overfill prevention equipment at installation – this would qualify as the first inspection. When inspecting, owners and operators must at a minimum ensure the overfill prevention equipment is set to activate at the correct level in the tank (the level depends on the type of overfill device) and will activate when regulated substances reach that level.

Overfill prevention equipment must be inspected according to one of the following:

  • Requirements developed by the manufacturer (owners and operators may only use this option if the manufacturer has developed inspection requirements)
  • A code of practice developed by a nationally recognized association or independent testing laboratory
  • Requirements determined by the implementing agency to be no less protective than those developed by the manufacturer or in the code of practice

Owners and operators must maintain records of overfill prevention equipment inspections for at least three years.

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Spill Prevention Equipment And Containment Sump Testing

Beginning on October 13, 2018 owners and operators must meet one of the following for spill containment equipment and for containment sumps used for piping interstitial monitoring:

Option 1: Spill prevention and containment sump equipment is double walled and the integrity of both walls is monitored at least as frequently as in the walkthrough inspection requirement (typically every 30 days for spill buckets but it may be longer if the facility receives infrequent deliveries, and annually for containment sumps). If owners and operators discontinue this periodic monitoring, they have 30 days to conduct the test described in option 2 below.

Option 2: Spill prevention equipment and containment sumps used for interstitial monitoring of piping are tested at least once every three years. The test must determine the equipment is liquid tight by using either vacuum, pressure, or liquid testing according to one of the following:

  • Requirements developed by the manufacturer (owners and operators may only use this option if the manufacturer has developed testing requirements)
  • A code of practice developed by a nationally recognized association or independent testing laboratory
  • Requirements determined by the implementing agency to be no less protective than those developed by the manufacturer or in the code of practice

Owners and operators must maintain records of spill prevention equipment and containment sump testing for at least three years. For spill prevention equipment and containment sumps used for interstitial monitoring of piping not tested every three years, owners and operators must maintain documentation showing the equipment is double walled and the integrity of both walls is periodically monitored for as long as the equipment is periodically monitored.

Spill prevention equipment and containment sumps used for interstitial monitoring of piping installed after October 13, 2015 must be tested for liquid tightness at installation and then once every three years. Note that most installation codes of practice require testing of this equipment for liquid tightness at installation – this would qualify as the first test.

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Release Detection Equipment Testing

Beginning on October 13, 2018 owners and operators must test electronic and mechanical components of their release detection equipment for proper operation at least annually using one of the following options:

  • Manufacturer’s instructions
  • A code of practice developed by a nationally recognized association or independent testing laboratory
  • Requirements developed by the implementing agency

When testing, check the following:

  • Automatic tank gauge and other controllers
    • Test the alarm
    • Verify the system configuration
    • Test the battery backup
  • Probes and sensors
    • Inspect for residual buildup
    • Ensure any floats move freely
    • Ensure any shafts are not damaged
    • Ensure the cables are free of kinks and breaks
    • Test the alarm operability and communication with the controller
  • Automatic line leak detector
    • Ensure the device activates (alarms, restricts flow, or shuts off flow) within an hour when simulating a release equivalent to 3 gallons per hour at 10 pounds per square inch
  • Vacuum pumps and pressure gauges
    • Ensure there is proper communication with sensors and the controller
  • Hand-held electronic sampling equipment associated with groundwater and vapor monitoring
    • Ensure the device operates properly

Owners and operators must maintain records of release detection equipment testing for at least three years. The record must include each component tested, whether each component passed the test or needed to have action taken, and any action taken to correct an issue.

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