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What to Do After a Flood - Underground Motor Fuel Storage Tanks

If an underground motor fuel storage tank system has been involved in a flood, there are certain measures that tank owners should take to safely return the system to operation, but only after flood waters have receded and local officials have allowed re-entry. The checklist below (which may also be downloaded as a PDF file through the link on the right of this page) can be used to help tank owners assess and return underground motor fuel storage tanks to service after a flood. This list of Bulk Storage Regional Contacts can help tank owners find local assistance.

NOTE: You may need to retain a contractor to undertake some of the actions listed below. If you are unfamiliar with any of the system components or procedures listed, DEC recommends that you contact a tank contractor for assistance.

Actions to Be Taken Before System Startup

  • Make sure that the power has been turned off to any tank system equipment (such as dispensers, pumps, leak detection equipment, etc).
  • Determine whether product has leaked from the tank system by inspecting areas around the tank, including any secondary containment, sumps, and under-dispenser containment.
  • Inspect the tank cover pad for damage that may indicate possible tank movement. (If the tank cover pad is damaged, have a tank contractor evaluate the tank system for damage.)
  • Determine whether water or debris has entered the tank system by using a gauging stick and water-finding paste.
  • If water is detected in the bottom of a tank storing ethanol-blended gasoline, test the fuel in the tank to ensure that it meets fuel quality standards.
  • After inspecting the electrical system for damage, return power to the tank system. (If there is cause for concern, contact a tank contractor or electrician.)
  • Check critical safety devices (such as shear valves, stop switches, isolation relays on dispensers, etc) for proper operation.
  • Check the leak detection system for proper operation. Restart leak detection as soon as possible after the flood.
  • Check all other equipment (including pumps, fill pipes, and vent lines) to ensure that it is undamaged. Inspect vent lines for movement and cracking.
  • Empty and clean spill buckets and sumps (including those underneath dispensers, as well as on top of tanks). Inspect piping and fittings for damage and possible leaks.
  • If there is any concern about the tightness of a tank system, perform a tank system tightness test to ensure integrity prior to adding product.

Actions to Be Taken At System Startup

  • The tank system may be returned to service even if the leak detection system is inoperable, as long as there is no indication that the tank system is leaking. Daily inventory control and reconciliation (including measuring for the presence of water on the tank bottom) may be used as an interim leak detection method while waiting for the leak detection system to be repaired. If there is an inventory loss or recurring accumulation of water, the tank system must be taken out-of-service until it has been tested to ensure that it is tight.

Actions to Be Taken as Soon as Practicable

  • Test spill buckets and sumps to ensure that they are tight.
  • Test cathodic protection (if present) to ensure that it is working properly.
  • If water has entered the interstitial spaces of tanks or product lines, the interstitial spaces must be drained and flushed.
  • If there is no leak detection system installed, perform a tank system tightness test to ensure integrity (if it was not performed in earlier steps).
  • Test all components of leak detection systems (such as electronic monitoring consoles, line leak detectors, sensors, etc) for functionality and operability.

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