prevention equipment, and overfill prevention equipment – needs to be compatible with the fuel stored to prevent releases to the environment. Biofuel blends with ethanol up to 98 percent (E98) and biodiesel up to 99 percent (B99) have been stored compatibly in some UST systems around the country. EPA thinks most UST systems are not fully compatible with higher blends of biofuels because many were installed before some compatible UST system equipment was available. EPA updated the compatibility requirements in the 2015 UST regulation to ensure higher blends of biofuels will be stored only in compatible UST systems. The 2015 UST regulation describes the steps UST owners and operators must take to help protect our health and environment from potential UST releases due to incompatibility. These steps will also help you avoid the high cost of cleaning up releases and possible legal actions that can result if your UST system releases product to the environment. Check With Your Implementing Agency Many states and territories (referred to as states in this booklet) have state program approval from EPA. To find a list of states with state program approval, see . If your UST systems are located in a state with state program approval, your requirements may be different from those identified in this booklet. Check with the state UST program in the state where your USTs are located. If your UST systems are located in a state without state program approval, both the requirements in this booklet and the state requirements apply to you. If your UST systems are located in Indian country, the requirements in this booklet apply to you. Compatibility Requirements In The 2015 UST Regulation The 2015 UST regulation maintains the requirement that all UST systems must be made of or lined with materials compatible with the substance stored in the UST system. The 2015 UST regulation provides clarity to the 1988 compatibility requirement by specifying additional compatibility requirements for owners and operators wishing to store certain regulated substances, including gasoline containing more than 10 percent ethanol and diesel containing greater than 20 percent biodiesel. Research has identified these substances as having a higher likelihood of incompatibility with many existing UST systems. By targeting the additional compatibility requirements toward the specific subset of the UST operating universe with the highest risk of failure due to incompatibility, the overall risk of releases will be minimized. The 2015 UST compatibility requirements incorporate some elements similar to EPA’s 2011 Guidance On Compatibility Of UST Systems With Ethanol Blends Greater Than 10 Percent And
Biodiesel Blends Greater Than 20 Percent (), including demonstrating that the UST system is compatible with the substance stored and keeping certain records. Beginning on October 13, 2015, in addition to the 1988 requirement of ensuring that the UST system is compatible, UST owners and operators intending to regulated substances must also meet these additional compatibility requirements: Notification You must notify your implementing agency at least 30 days before switching to any of the following products: Regulated substances containing greater than 10 percent ethanol Regulated substances containing greater than 20 percent biodiesel Any other regulated substance identified by your implementing agency Please see Appendix 1 for a sample letter for notifying your implementing agency that you plan to switch to store a biofuel. Additionally, owners and operators storing one or more of regulated substances must meet the compatibility requirement by demonstrating compatibility of the system with the fuel or by using an alternative method approved by the implementing agency: Demonstration of compatibility If you store any of these substances, you must either: Demonstrate that the following UST system components are compatible with the regulated substance: tank, piping, containment pumping equipment, release detection equipment, spill prevention equipment, and overfill prevention equipment Use another option determined by the implementing agency to be no less protective of human health and the environment than the demonstration method Recordkeeping Beginning on October 13, 2015, if you store regulated substances containing greater than 10 percent ethanol, greater than 20 percent biodiesel, or other substances identified by your implementing agency, you must keep records showing that your UST system is compatible with those substances. If you choose to follow an alternative method determined to be no less protective of human health and the environment established by your implementing agency, then you must keep documentation of adherence to this requirement as required by the implementing agency’s rules. You must keep these records for as long as you store these regulated substances Owners and operators may wish to consult American Petroleum Institute’s Recommended Practice 1626, Storing and Handling Ethanol and Gasoline-Ethanol Blends at Distribution