Storage Tank & Environmental Liability Insurance Insurance: Average Premiums & Pricing Factors

Storage tank insurance and environmental liability coverage protects businesses from the costs of underground and aboveground storage tank leaks, spills, and contamination — including cleanup costs, third-party bodily injury, property damage, and regulatory response.

What You Need to Know

Underground storage tank (UST) insurance is required by federal EPA regulations for most UST operators. It covers corrective action (site cleanup), third-party bodily injury and property damage from releases, and legal defense costs. Environmental liability insurance (also called pollution liability) extends coverage to aboveground spills, gradual contamination, and site remediation. Coverage is critical for gas stations, fuel distributors, industrial facilities, and any business with fuel or chemical storage.

Storage Tank & Environmental Liability Insurance Cost by Business Size

What Determines Your Premium?

• Number of Tanks and Tank Age (Very High impact) — More tanks = more exposure. Older tanks (steel, pre-1988) carry higher risk. New fiberglass double-wall tanks have substantially better underwriting profiles.
• Product Type (High impact) — Petroleum products (gasoline, diesel) are the most common. Hazardous chemicals, aviation fuel, and heating oil have varying risk profiles and may require specialty programs.
• Site Conditions (High impact) — Proximity to drinking water sources, depth to groundwater, and soil type affect cleanup cost exposure. Sites over shallow aquifers used for drinking water command much higher premiums.
• Prior Claims / Known Contamination (Very High impact) — Sites with prior releases or known contamination face significant underwriting challenges. Pre-existing contamination exclusions are standard; coverage for known contamination requires specialized programs.
• Compliance Status (High impact) — Facilities in compliance with leak detection, corrosion protection, and overfill protection requirements have much better underwriting profiles. Non-compliance can result in coverage denial.
• State Fund Participation (Medium impact) — California USTIF and other state funds provide a layer of coverage that reduces commercial policy exposure in some states, reducing commercial premium needs.