trucks: Maintaining Your USTs

Bob Deierlein

With a federal mandate to replace or upgrade existing underground storage tanks (UST) only two years away, managers of refuse/ recycling fleets are giving this area more attention.

Whether you choose to upgrade or replace, USTs must be maintained carefully. This maintenance revolves around certain areas where problems occur frequently. For example, the pump pit of a tank that has a submerged pumping system should be checked periodically for leakage. Over time, a tank moves relative to its piping, and threaded joints can loosen or fittings can crack.

The line leak detector on a sub-merged pumping systems also must be checked periodically to make sure it is working and activates when line pressure is lost. The problem of false signals on these units has been solved and should be used on all pressurized lines.

Check periodically to ensure that the impact/fire valve under the service pump of a submerged pumping system works properly and is not leaking. The shear section can be cracked by a minor collision with the service pump.

Signs of leakage in all visible piping connections for under and inside the base of the service pump should be inspected regularly.

The tank fill and gauge risers should be checked frequently to make sure they are not damaged or loose and that their caps are properly installed and have good seals. Anytime a tank has two or more openings at grade level and the openings are not tightly capped, surface water can enter the tank through one opening and "float" product out to the other(s).

Check the underground tank itself for evidence of water build-up. While water will accumulate normally and gradually in tanks due to condensation, any sudden or rapid increase in water level, especially if all caps are tight, indicates the system is no longer tight and may be leaking.

Dispose of the normal water build-up in tanks. Water does accumulate and can cause problem with corrosion and bacterial growth. Underground tank maintenance contractors generally have equipment to remove inaccessible water bottoms and any accumulated sludge.

If the storage tank contents normally are checked with the gauge stick, verify periodically that the tank bottom protector under the gauge opening is still in place. Repeated impact of a gauge stick on the tank's bottom can produce perforation.

If the tank and lines are equipped with cathodic protection, the proper operation of the system must be verified periodically to ensure that the necessary level of corrosion protection is being maintained.

Finally, a routine process must be developed of reconciling the amount of product in the tank with what should be in a tank. While leak detection is required by state and federal regulation, it also makes good business sense because this is the best method to determine if underground storage tanks are doing what they are supposed to do, and heading off problems before they become major.

Certification Smithers Quality Assessment Inc., a registrar based in Akron, Ohio, granted Alcoa Wheel Products International, Cleveland, QS 9000 certification after auditing its manufacturing process for forged aluminum wheels.

Contracts Alton Labs, Framingham, Mass., has won a bid with the United States Postal Service, Pittsburgh district, to manufacture 3,000, 100-percent recycled plastic chock blocks for its fleet vehicles.