FRP Secondary Containment for Chemical Storage

Spill containment is a legal and safety requirement wherever bulk chemicals are stored above ground. A secondary containment basin catches leaks from tanks, valves, and pipe joints before they reach the environment. FRP (glassfiber reinforced plastic) is an ideal material for containment because it is seamless, corrosion-resistant, and easy to clean. This article explains how to size and specify an FRP containment system.

Regulatory Basis

Most codes require secondary containment to hold 110 percent of the volume of the largest tank, or 25 percent of total stored volume, whichever is larger. The containment must also be weathertight and compatible with every chemical that may spill. Confirm the requirement with the local environmental authority before design.

Construction Options

• FRP-lined concrete basin: the most common and economical solution; a FRP laminate is laid over steel-trowelled concrete after it cures.

• Molded FRP trench and sump: prefabricated sections joined in the field; useful for small bunds around individual drums or IBCs.

• Self-supporting FRP pan: used where the existing floor cannot be modified and a freestanding tray is acceptable.

Lining Details

The interior laminate should include a corrosion barrier (surface veil plus one layer of C-glass or vinyl ester mat) followed by structural layers. Penetrations for drains and cable conduits must be sealed with boot details. Provide a sloped floor toward a drain or sump so spills can be collected and pumped out.

Inspection and Maintenance

Inspect the lining annually for cracks, blisters, or disbondment. Spark test the lining every few years after a major spill. Repair any damage promptly; a small pinhole lets chemicals under the laminate and causes widespread delamination over time.

Conclusion

FRP secondary containment provides a durable, code-compliant spill barrier. Correct sizing, compatible resin selection, and regular inspection keep it effective over decades of service.

References

• EPA SPCC — Spill Prevention, Control, and Countermeasure Rule

• GB 18597 — Storage Containment for Hazardous Wastes