CWD Well Construction & Casing Design 2

Question 1

What is the primary purpose of casing centralizers used during well construction?

Accepted Answer

To keep the casing centered in the borehole for uniform annular grout placement

Answer

To increase the weight of the casing string for easier installation

Answer

To prevent groundwater from entering the borehole during drilling

Answer

To measure the true diameter of the completed borehole

Question 2

Which well screen type provides the most precise slot sizing and is best suited for fine sand formations?

Accepted Answer

Wire-wound continuous slot screen

Answer

Torch-cut slotted pipe

Answer

Machine-slotted perforated pipe

Answer

Bridge-slotted casing

Question 3

What AWWA standard primarily governs the construction of drilled water wells in the United States?

Accepted Answer

AWWA A100

Answer

AWWA A200

Answer

AWWA C900

Answer

AWWA B300

Question 4

What is a pitless adapter, and what problem does it solve in well construction?

Accepted Answer

A fitting that allows the water line to exit the casing below the frost line while maintaining a sanitary seal

Answer

A tool used to retrieve debris from the bottom of a completed well

Answer

A type of submersible pump designed for shallow pitless installations

Answer

A grout injection device for sealing the lower annular space

Question 5

Which material is most commonly approved for sealing the annular space around a well casing?

Accepted Answer

Bentonite clay or neat cement grout

Answer

Sand and gravel mixture

Answer

Crushed limestone aggregate

Answer

Epoxy resin compound

Question 6

What is the purpose of a conductor casing in a well construction program?

Accepted Answer

To guide drilling, prevent near-surface formation collapse, and enable drilling fluid circulation

Answer

To carry electrical conduit safely from the surface to the pump

Answer

To measure electrical conductivity of the groundwater column

Answer

To transfer structural casing loads through soft overburden to bedrock

Question 7

When placing annular grout using the tremie method, in which direction should grout be pumped to ensure a void-free seal?

Accepted Answer

From the bottom of the annular space upward, displacing drilling fluids

Answer

From the surface downward through the annular space

Answer

Horizontally through ports drilled in the casing at multiple depths

Answer

In alternating directions to achieve even distribution