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Secondary containment for oil-filled operation equipment under SPCC

On December 26, 2006, EPA provided an optional alternative to the general secondary containment requirements in 40 CFR §112.7(c) for qualified oil-filled operational equipment (71 FR 77266). Because the alternative is optional, an owner or operator could choose to comply with the existing SPCC requirements to provide general secondary containment for each piece of qualified oil-filled operational equipment. What are some general secondary containment options for oil-filled operational equipment, if a facility chooses not to take advantage of the alternative?

Facilities must use one of the prevention systems listed in §112.7(c) or an equivalent to provide appropriate containment or diversionary structures or equipment to prevent a discharge as described in §112.1(b). For example, oil-filled operational equipment is often surrounded by a gravel bed, which serves as a passive fire quench system and support for the facility grounding network that can restrict the movement of oil in the event of a release. Gravel beds, if designed to prevent a discharge as described in §112.1(b) (i.e., drainage systems that do not serve as a conduit to surface waters), may meet the general secondary containment requirements of §112.7(c). EPA further notes that oil-filled operational equipment located within buildings with limited drainage and which prevent a discharge as described in §112.1(b), may already meet the requirements for general secondary containment in §112.7(c). For certain electrical equipment, permanent (or passive) containment structures, such as dikes, may not be feasible. Section 112.7(c) allows for the use of certain types of active containment measures (countermeasures or spill response capability), which prevent a discharge to navigable waters or adjoining shorelines. Examples of active containment measures include deploying sorbent material, using spill kits, or covering drain openings.