Transformer Spill Containment

[saladhawks]

I was curious what other U.S. utilities require in relation to transformer spill containment in above-ground installations. The utility that I work for installs above-ground transformers in enclosures that include a 6" spill containment curb. There is a sump in the enclosure that drains to crushed rock below.

Neighboring utilities in my state (California) frequently use padmounted transformers with no spill containment. I am curious as to the reasons behind this decision and what they would do if one of the padmount units started leaking oil.

 

[dpc]

In the US, the Federal EPA generally does not require oil containment. It just says that transformer owner is responsible for any impact of an oil spill. You are also required to have a mitigation plan in the event of an oil spill.

Small leaks are dealt with by portable control/containment devices. For a major blow out, the transformer is removed and they bring in an environmental contractor to dig up all of the contaminated soil and haul it off.

In some substations, a plastic liner is placed under the gravel and sloped to drain to a separator or sump, so no curb is used.

 

[Electic]

Locally no containment is used except in substations. All transformers have been tested to be PCB free. Oil containment may also be a fire code issue if near buildings etc.

Interesting to consider the containment challenge for OH banks that often rupture tanks when hit by lightning. Not practical, and little harm caused by mineral oil.

 

[wfowfo]

Some states require it based on the gallons of oil at the facility.

 

[gobblerhuntr]

Google: Spill Prevention, Control and Countermeasure