UST Release Detection & Prevention 2 — Questions and Answers
Question 1: Under EPA regulations, how frequently must automatic tank gauging (ATG) systems be tested for performance?
- Monthly
- Quarterly
- Annually (Correct answer)
- Every three years
Correct answer: Annually
EPA requires ATG systems to undergo annual performance testing to verify they can detect a leak at the required threshold.
Question 2: Which of the following is an approved method for release detection on pressurized piping?
- Monthly inventory reconciliation
- Automatic line leak detector (Correct answer)
- Manual stick gauging
- Vapor monitoring in the dispenser sump
Correct answer: Automatic line leak detector
Automatic line leak detectors are the required or approved method for pressurized piping because they restrict or stop product flow if a leak is detected.
Question 3: What is the minimum leak rate that a monthly automatic tank gauging test must be capable of detecting?
- 0.1 gallon per hour
- 0.2 gallon per hour (Correct answer)
- 0.5 gallon per hour
- 1.0 gallon per hour
Correct answer: 0.2 gallon per hour
EPA regulations require monthly ATG tests to detect leaks of 0.2 gallon per hour with a probability of detection of 95% and a probability of false alarm of 5%.
Question 4: A groundwater monitoring well used for UST release detection must be installed by a(n):
- Certified UST operator
- Licensed well driller or qualified professional (Correct answer)
- Equipment manufacturer representative
- State fire marshal inspector
Correct answer: Licensed well driller or qualified professional
Groundwater monitoring wells must be installed by a licensed well driller or qualified professional to ensure proper placement and avoid cross-contamination.
Question 5: Which condition would cause an automatic line leak detector to trigger a 'restricted flow' response?
- High product demand during peak hours
- A leak rate of 3 gallons per hour or greater (Correct answer)
- Vapor pressure exceeding dispenser limits
- Unusually cold product temperature
Correct answer: A leak rate of 3 gallons per hour or greater
Automatic line leak detectors are designed to restrict or halt product flow when they detect a leak of 3 gallons per hour or more.
Question 6: Statistical inventory reconciliation (SIR) is considered which type of release detection method?
- Manual method requiring weekly data entry
- Non-volumetric method based on vapor analysis
- Third-party analytical method using delivery and sales data (Correct answer)
- Real-time automated sensor-based monitoring
Correct answer: Third-party analytical method using delivery and sales data
SIR is a third-party analytical method that applies statistical analysis to inventory, delivery, and dispensing data to detect releases.
Question 7: When using vapor monitoring as a release detection method, sensors must be placed:
- Inside the tank manway
- In the product lines at the dispenser
- In the soil or groundwater near the tank (Correct answer)
- On top of the vent pipe
Correct answer: In the soil or groundwater near the tank
Vapor monitoring sensors are installed in the soil or groundwater surrounding the tank to detect hydrocarbon vapors that indicate a release.
UST Release Detection & Prevention 2
Under EPA regulations, how frequently must automatic tank gauging (ATG) systems be tested for performance?