The drilling method used to construct a monitoring well should...

• A. Minimize the risk of subsurface contamination
• B. Maximize drilling speed
• C. Minimize cost
• D. Minimize noise

Answer: (A)

The main goal when constructing a monitoring well is to protect groundwater sample integrity. The drilling method should minimize the risk of introducing contaminants into the subsurface, prevent cross-contamination between aquifers, and ensure a proper annular seal and well completion that isolates the screened interval from surface infiltration. Clean drilling practices, appropriate casing and grout, and careful control of drilling fluids all help keep samples representative of the groundwater rather than of surface or drilling-related contaminants. While speed, cost, or noise are considerations, they should not compromise the ability to accurately monitor groundwater quality.