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Underground Storage Tanks (USTs)

Class A and Class B UST Operator Exams

EPA developed class A and class B UST operator exams to primarily help UST system owners and operators in Indian country meet the 2015 federal UST regulation requirement that designated operators demonstrate knowledge.  October 13, 2018 is the deadline for designated operators to verify compliance with the requirement to pass an exam.  

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Typical UST facilities are gas stations, convenience stores, and other non-retail facilities. 

Airport hydrant fueling systems and UST systems with field-constructed tanks are regulated under 40 CFR Part 280, Subpart K.

Access UST Operator Exam

EPA is making these exams easily accessible and at no cost to all designated operators.  The type of UST facility determines the exams designated operators must complete. 

Typical UST system designated operators must complete:

  • Comprehensive exam Exit — class A operator covers 11 topics; class B operator covers 9 topics
  • Topic-specific exams Exit — allow class A and B operators to complete re-examination on topics required due to UST system non-compliance, per your implementing agency

Airport hydrant fueling system (AHS) and UST system with field-constructed tank (FCT) designated operators must complete the comprehensive exam as well as the AHS or FCT specific topic, as applicable.

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Successfully Complete UST Operator Exam

You must correctly answer at least 80 percent of the exam’s questions in order to successfully pass and print a certificate of completion, which meets the operator training documentation required under 40 CFR, Subpart J.  You may retake the exam an unlimited number of times in order to pass it.  You will be able to access a printout about those questions you answered incorrectly.  To help prepare for the exam and familiarize yourself with the federal UST requirements, EPA recommends you review the documents listed below; you may use them while taking the exam.

Remember to print or download your certificate of completion before exiting the system.  You will have to retake the exam to obtain proof of completion.

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About EPA’s UST Operator Exam

Question:  Can a designated class A or B operator use this online exam–that is, pass the exam with 80 percent or greater and print a certificate–to meet state or other implementing agency requirements for operator training?

Answer:  The answer depends on requirements of the UST implementing agency.  Although passing the exam demonstrates required knowledge for the federal UST regulation, states and other implementing agencies may have different requirements.  Contact your UST implementing agency for specific information on operator training requirements.  In Indian country, EPA is the implementing agency, so passing this online exam meets requirements in 40 CFR, Subpart J.

Question:  Can a designated class A or B operator in Indian country take UST operator training provided by a state or other organization, such as a private sector training provider, to meet the federal operator training requirements, instead of using this exam?

Answer:  Yes, as long as that state or private training incorporates all the provisions and topics included in 40 CFR 280.242(a) and (b).  Note, some existing state and private training do not incorporate all the necessary provisions.

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