UST Tank Installation & Closure Procedures 3

Question 1

Under EPA regulations, a UST is considered temporarily closed when it is taken out of service for how long a period?

Accepted Answer

3 months or more (but less than 12)

Answer

A UST is classified as temporarily closed when out of service for 3 months or more but less than 12 months, triggering specific requirements such as leaving vent lines open and capping all other lines.

Question 2

When permanently closing a UST in place (abandonment in place), what must be done to the tank interior?

Accepted Answer

Filled with an inert solid material such as concrete slurry or foam

Answer

When permanently closing a UST in place, the tank must be emptied, cleaned, and then filled with an inert solid material (e.g., concrete slurry or sand) to eliminate the void and explosion hazard.

Question 3

Before a UST is permanently closed or removed from service, site assessment activities must include sampling for what?

Accepted Answer

Petroleum hydrocarbons and regulated substances in soil and groundwater

Answer

A site assessment at permanent closure must include sampling soil and groundwater for petroleum hydrocarbons and other regulated substances to determine whether a release has occurred.

Question 4

How long must records related to the permanent closure of a UST system be retained by the owner/operator?

Accepted Answer

At least 10 years

Answer

Closure records, including the site assessment results and closure report, must be retained for at least 10 years following permanent closure.

Question 5

When removing a UST from the ground, what safety step must be taken before excavation to control vapor hazards?

Accepted Answer

Removing all residual product and cleaning the tank to below explosive limits

Answer

Before removal, the tank must be emptied of all product and residual vapors must be reduced below the lower explosive limit (LEL) to prevent ignition during excavation and cutting.

(UST) Underground Storage Tank Certification Practice Test

(UST) Underground Storage Tank Certification Practice Test

UST Tank Installation & Closure Procedures 3