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

Less than 3 months

Answer

3–12 months

Answer

More than 24 months

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

Filled with water to prevent collapse

Answer

Left empty with all openings sealed with plugs

Answer

Purged with nitrogen and sealed airtight

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

Heavy metals in the tank walls

Answer

Radon gas levels in the surrounding soil

Answer

pH levels of the excavation water

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

1 year

Answer

3 years

Answer

Indefinitely as long as they own the property

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

Purging all product lines with nitrogen

Answer

Installing a vapor barrier around the tank before digging

Answer

Flooding the excavation with water before cutting the tank

Question 6

Which regulatory standard requires that UST closure activities be performed or overseen by a certified professional?

Accepted Answer

40 CFR Part 280, Subpart G

Answer

40 CFR Part 260

Answer

29 CFR 1910.119

Answer

49 CFR Part 173

Question 7

If contamination is found during UST closure site assessment, what is the next required step?

Accepted Answer

Report the release and initiate corrective action per the implementing agency's requirements

Answer

Immediately backfill the excavation to contain the contamination

Answer

Remove only the visibly contaminated soil and close the site

Answer

Submit a written request to the EPA for a site exemption