ICC U2 UST Decommissioning Exam Prep:
Underground Storage Tank Practice Questions &
Rationales
This specialized technical preparation resource provides targeted practice questions,
verified answers, and detailed regulatory rationales for the International Code Council
(ICC) U2 Underground Storage Tank (UST) Decommissioning certification. It
systematically covers the core safety protocols and engineering guidelines required for
tank removal, including site assessment, permanent closure procedures, vapor freeing,
and soil safety testing. Environmental technicians and safety engineers will master
critical OSHA, EPA, and API standards to ensure a passing score on this highly
technical environmental licensing track.
Question 1
Underground petroleum storage systems that are no longer needed or suitable for
product storage must be properly ____________.
A) Removed from the site
B) Decommissioned and disposed of properly
C) Sold as used equipment
D) Left in place without treatment
Correct Answer: B) Decommissioned and disposed of properly
Rationale: When USTs are no longer needed, they must be properly decommissioned
(closed) by either removal from the ground or closure in place, following all regulatory
requirements under API 1604 and 40 CFR Part 280 .
,Question 2
All work that is completed at the site must be accomplished in accordance with:
A) Federal requirements only
B) State requirements only
C) Federal, state, and local requirements as well as accepted safety standards
D) The owner's preferences
Correct Answer: C) Federal, state, and local requirements as well as accepted safety
standards
Rationale: All decommissioning work must comply with federal, state, and local
regulations along with accepted safety standards to ensure legal compliance and worker
protection .
Question 3
What is the primary hazard that removers of petroleum tanks are faced with?
A) Heavy equipment operation
B) Petroleum hydrocarbon liquids, vapors, and waste
C) Noise pollution
D) Traffic control
Correct Answer: B) Petroleum hydrocarbon liquids, vapors, and waste
,Rationale: The primary hazards in UST decommissioning are petroleum hydrocarbon
liquids, flammable vapors, and hazardous waste materials. These pose fire, explosion, and
health risks to workers .
Question 4
What are some symptoms of inhaling or absorbing high levels of petroleum
hydrocarbon vapors?
A) Dizziness, excitement, unconsciousness
B) Increased energy and alertness
C) Improved vision
D) Enhanced sense of smell
Correct Answer: A) Dizziness, excitement, unconsciousness
Rationale: Exposure to high levels of petroleum hydrocarbon vapors can cause dizziness,
excitement (euphoria), and unconsciousness. Workers must use appropriate PPE and
monitoring equipment .
Question 5
A temporary closure is appropriate for which of the following?
A) The UST system is empty and will be removed from service indefinitely
B) The UST system has ceased to store hazardous materials but will be used within the
next 12 consecutive months
, C) The UST system is unable to meet compliance requirements and will be removed
D) The UST system has been red-tagged
Correct Answer: B) The UST system has ceased to store hazardous materials but
will be used within the next 12 consecutive months
Rationale: Temporary closure is appropriate when a UST system has ceased storing
hazardous materials but will be used within the next 12 consecutive months, as specified
in CCR Title 23, Sec 2671 & 2670 .
Question 6
If a UST system is utilizing an overfill alarm, the alarm must be triggered to alert the
transfer operator when the tank is no more than ___________ full.
A) 85%
B) 95%
C) 90%
D) 80%
Correct Answer: C) 90%
Rationale: The overfill alarm must trigger when the tank is no more than 90% full, as
required by CCR Title 23, Sec 2635(b)(2)(A) .
Question 7
An unauthorized release which does not escape from secondary containment only
requires a record on the operator's monitoring reports provided that:
Underground Storage Tank Practice Questions &
Rationales
This specialized technical preparation resource provides targeted practice questions,
verified answers, and detailed regulatory rationales for the International Code Council
(ICC) U2 Underground Storage Tank (UST) Decommissioning certification. It
systematically covers the core safety protocols and engineering guidelines required for
tank removal, including site assessment, permanent closure procedures, vapor freeing,
and soil safety testing. Environmental technicians and safety engineers will master
critical OSHA, EPA, and API standards to ensure a passing score on this highly
technical environmental licensing track.
Question 1
Underground petroleum storage systems that are no longer needed or suitable for
product storage must be properly ____________.
A) Removed from the site
B) Decommissioned and disposed of properly
C) Sold as used equipment
D) Left in place without treatment
Correct Answer: B) Decommissioned and disposed of properly
Rationale: When USTs are no longer needed, they must be properly decommissioned
(closed) by either removal from the ground or closure in place, following all regulatory
requirements under API 1604 and 40 CFR Part 280 .
,Question 2
All work that is completed at the site must be accomplished in accordance with:
A) Federal requirements only
B) State requirements only
C) Federal, state, and local requirements as well as accepted safety standards
D) The owner's preferences
Correct Answer: C) Federal, state, and local requirements as well as accepted safety
standards
Rationale: All decommissioning work must comply with federal, state, and local
regulations along with accepted safety standards to ensure legal compliance and worker
protection .
Question 3
What is the primary hazard that removers of petroleum tanks are faced with?
A) Heavy equipment operation
B) Petroleum hydrocarbon liquids, vapors, and waste
C) Noise pollution
D) Traffic control
Correct Answer: B) Petroleum hydrocarbon liquids, vapors, and waste
,Rationale: The primary hazards in UST decommissioning are petroleum hydrocarbon
liquids, flammable vapors, and hazardous waste materials. These pose fire, explosion, and
health risks to workers .
Question 4
What are some symptoms of inhaling or absorbing high levels of petroleum
hydrocarbon vapors?
A) Dizziness, excitement, unconsciousness
B) Increased energy and alertness
C) Improved vision
D) Enhanced sense of smell
Correct Answer: A) Dizziness, excitement, unconsciousness
Rationale: Exposure to high levels of petroleum hydrocarbon vapors can cause dizziness,
excitement (euphoria), and unconsciousness. Workers must use appropriate PPE and
monitoring equipment .
Question 5
A temporary closure is appropriate for which of the following?
A) The UST system is empty and will be removed from service indefinitely
B) The UST system has ceased to store hazardous materials but will be used within the
next 12 consecutive months
, C) The UST system is unable to meet compliance requirements and will be removed
D) The UST system has been red-tagged
Correct Answer: B) The UST system has ceased to store hazardous materials but
will be used within the next 12 consecutive months
Rationale: Temporary closure is appropriate when a UST system has ceased storing
hazardous materials but will be used within the next 12 consecutive months, as specified
in CCR Title 23, Sec 2671 & 2670 .
Question 6
If a UST system is utilizing an overfill alarm, the alarm must be triggered to alert the
transfer operator when the tank is no more than ___________ full.
A) 85%
B) 95%
C) 90%
D) 80%
Correct Answer: C) 90%
Rationale: The overfill alarm must trigger when the tank is no more than 90% full, as
required by CCR Title 23, Sec 2635(b)(2)(A) .
Question 7
An unauthorized release which does not escape from secondary containment only
requires a record on the operator's monitoring reports provided that:
