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What Are The Requirements For Hazardous Substance USTs?

In 2015, EPA revised the underground storage tank (UST) regulations. Below you will find the requirements for hazardous substance USTs.

UST systems that store substances identified as being hazardous under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) are subject to the same requirements as petroleum UST systems, including secondary containment. Hazardous wastes are already regulated under Subtitle C of the Resource Conservation and Recovery Act (RCRA) and therefore are not covered by the UST regulations.

Currently about 1,200 substances (excluding radionuclides) are identified as hazardous under CERCLA (see 40 CFR 302, section 302.4).

What Is Secondary Containment?

All hazardous substance USTs must have secondary containment. A single-walled tank is the first or primary containment. Using only primary containment, a leak can escape into the environment. But by enclosing an UST within a second wall, leaks can be contained and detected quickly before harming the environment.

There are several ways to construct secondary containment:

What About Leak Detection?

The hazardous substance UST must use interstitial monitoring for leak detection. Interstitial monitoring can indicate the presence of a leak in the confined space between the first and the second wall. Several devices are available to monitor this confined interstitial space. The UST regulations describe these various methods and the requirements for their proper use.

If your UST system was installed before [effective date of rule], you can apply for an exception, called a variance, from the requirement for secondary containment and interstitial monitoring. To obtain a variance you must demonstrate to the implementing agency that your alternative leak detection method will work effectively by providing detailed studies of your site, proposed leak detection method, and available methods for corrective action.

What About Spill, Overfill, and Corrosion Protection?

All UST systems are required to have spill, overfill, and corrosion protection.

What If You Have A Hazardous Substance Release?

Whether you have a confirmed release, or even if you suspect that you might have a release, you must follow the basic actions described below:

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