Who has to write a plan
40 CFR Part 112 applies to a facility that stores more than 1,320 gallons of oil aboveground or more than 42,000 gallons underground, where a discharge could reasonably reach navigable waters or adjoining shorelines. A small tank battery with three 500-barrel production tanks crosses the threshold fast. Facilities with 10,000 gallons or less of aggregate aboveground capacity and no qualifying discharge history can self-certify their SPCC plan instead of paying for a professional engineer's seal, per the qualified facility provisions.
Containment that matches the tank
The plan must describe secondary containment for bulk storage containers, sized to hold the largest single container plus room for rain, using dikes, berms, curbing, or a drainage system. The EPA allows one common collection area for several tanks, so a battery with a shared berm can comply as one system. Where containment is genuinely impracticable, the plan must say why and list the alternative measures taken in its place.
The inspection log is the plan
Integrity testing and visual inspections are required and must be recorded, because the log is what an inspector can verify. Plans must be reviewed every five years and amended within six months of a change that affects discharge potential, such as a new tank or a reworked drainage system. A plan written once and never touched is paperwork. A plan with dates, signatures, and test records is a control.
SPCC sits beside the other compliance routines an oilfield contractor inherits: ground disturbance tickets, COI and prequalification, and incident investigation. Every one of them runs on dated records. If the inspection schedule and amendment dates are tracked in a notebook, an operations audit will show which compliance deadlines are actually being met.