1|Page
WA UST Site Assessor Exam Questions With
Complete Solutions | 100% Pass
How long should written documentation of all calibration
maintenance, and repair of release detection equipment
be maintained? - .....ANSWER ...✔✔ At least 5 years
after servicing work is completed
What is the hold time for soil samples? - .....ANSWER
...✔✔ 14 days
What is the hold time for preserved GW GRO samples?
- .....ANSWER ...✔✔ 14 days
What does GRO stand for? - .....ANSWER ...✔✔
Gasoline Range Organics
Is an ICC certification needed to install an AST? -
.....ANSWER ...✔✔ No
What does ICC stand for? - .....ANSWER ...✔✔
International Code Council
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What is the LFL of Gasoline? - .....ANSWER ...✔✔
1.4%
What is the UFL of Gasoline? - .....ANSWER ...✔✔
7.6%
After a tank closure, how many days do you have to
report/provide the UST checklist to ECY? - .....ANSWER
...✔✔ 30
What is ECY an abbreviation for? - .....ANSWER
...✔✔ The Washington State Department of Ecology
What does CUL stand for? - .....ANSWER ...✔✔
Cleanup Level
What is the MTCA Method A lead CUL for soil? -
.....ANSWER ...✔✔ 250 mg/kg
What is the MTCA Method A lead CUL for GW? -
.....ANSWER ...✔✔ 15 ug/L
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What does MTCA stand for? - .....ANSWER ...✔✔
Model Toxics Control Act
What is the MTCA? - .....ANSWER ...✔✔ Washington's
cleanup act. It governs the cleanup and prevention of
contaminated sites that can threaten the health of
people and the environment.
What is the MTCA Method A GRO (without benzene)
CUL for soil? - .....ANSWER ...✔✔ 100 mg/kg
What is the MTCA Method A GRO (with benzene) CUL
for soil? - .....ANSWER ...✔✔ 30 mg/kg
What is the MTCA Method A GRO (with benzene) CUL
for GW? - .....ANSWER ...✔✔ 800 ug/L
What are MTCA Method A cleanup levels? -
.....ANSWER ...✔✔ The default human health cleanup
levels for soil, groundwater, surface water, air, and
vapor intrusion.
What is the MTCA Method A GRO (without benzene)
CUL for GW? - .....ANSWER ...✔✔ 1,000 ug/L
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What is the MTCA Method A DRO and ORO CUL for
soil? - .....ANSWER ...✔✔ 2,000 mg/kg
What is the MTCA Method A DRO and ORO CUL for
GW? - .....ANSWER ...✔✔ 500 ug/L
Is the vadose zone saturated or unsaturated? -
.....ANSWER ...✔✔ Unsaturated
List the following from most mobile to least mobile:
Diesel, Heating Oil, Bunker C oil, Gasoline - .....ANSWER
...✔✔ Gasoline, diesel, heating oil, Bunker C oil
What is the vadose zone? - .....ANSWER ...✔✔ The
portion of the subsurface above the GW table.
Is oxygenated gasoline more or less likely to dissolve in
water? - .....ANSWER ...✔✔ More likely
Why is oxygenated gasoline more likely to dissolve in
water? - .....ANSWER ...✔✔ Fuel additives like MTBE
are more soluble than gasoline.
WA UST Site Assessor Exam Questions With
Complete Solutions | 100% Pass
How long should written documentation of all calibration
maintenance, and repair of release detection equipment
be maintained? - .....ANSWER ...✔✔ At least 5 years
after servicing work is completed
What is the hold time for soil samples? - .....ANSWER
...✔✔ 14 days
What is the hold time for preserved GW GRO samples?
- .....ANSWER ...✔✔ 14 days
What does GRO stand for? - .....ANSWER ...✔✔
Gasoline Range Organics
Is an ICC certification needed to install an AST? -
.....ANSWER ...✔✔ No
What does ICC stand for? - .....ANSWER ...✔✔
International Code Council
,2|Page
What is the LFL of Gasoline? - .....ANSWER ...✔✔
1.4%
What is the UFL of Gasoline? - .....ANSWER ...✔✔
7.6%
After a tank closure, how many days do you have to
report/provide the UST checklist to ECY? - .....ANSWER
...✔✔ 30
What is ECY an abbreviation for? - .....ANSWER
...✔✔ The Washington State Department of Ecology
What does CUL stand for? - .....ANSWER ...✔✔
Cleanup Level
What is the MTCA Method A lead CUL for soil? -
.....ANSWER ...✔✔ 250 mg/kg
What is the MTCA Method A lead CUL for GW? -
.....ANSWER ...✔✔ 15 ug/L
,3|Page
What does MTCA stand for? - .....ANSWER ...✔✔
Model Toxics Control Act
What is the MTCA? - .....ANSWER ...✔✔ Washington's
cleanup act. It governs the cleanup and prevention of
contaminated sites that can threaten the health of
people and the environment.
What is the MTCA Method A GRO (without benzene)
CUL for soil? - .....ANSWER ...✔✔ 100 mg/kg
What is the MTCA Method A GRO (with benzene) CUL
for soil? - .....ANSWER ...✔✔ 30 mg/kg
What is the MTCA Method A GRO (with benzene) CUL
for GW? - .....ANSWER ...✔✔ 800 ug/L
What are MTCA Method A cleanup levels? -
.....ANSWER ...✔✔ The default human health cleanup
levels for soil, groundwater, surface water, air, and
vapor intrusion.
What is the MTCA Method A GRO (without benzene)
CUL for GW? - .....ANSWER ...✔✔ 1,000 ug/L
, 4|Page
What is the MTCA Method A DRO and ORO CUL for
soil? - .....ANSWER ...✔✔ 2,000 mg/kg
What is the MTCA Method A DRO and ORO CUL for
GW? - .....ANSWER ...✔✔ 500 ug/L
Is the vadose zone saturated or unsaturated? -
.....ANSWER ...✔✔ Unsaturated
List the following from most mobile to least mobile:
Diesel, Heating Oil, Bunker C oil, Gasoline - .....ANSWER
...✔✔ Gasoline, diesel, heating oil, Bunker C oil
What is the vadose zone? - .....ANSWER ...✔✔ The
portion of the subsurface above the GW table.
Is oxygenated gasoline more or less likely to dissolve in
water? - .....ANSWER ...✔✔ More likely
Why is oxygenated gasoline more likely to dissolve in
water? - .....ANSWER ...✔✔ Fuel additives like MTBE
are more soluble than gasoline.
