Groundwater · Groundwater and Aquifer Basics
What Is the Difference Between Confined and Unconfined Aquifers?
An unconfined aquifer has a water table open to atmospheric pressure through the materials above it. It is often more responsive to recharge, drought, and contamination from the surface. A confined aquifer lies beneath a layer that restricts water movement. Pressure may cause water in a well to rise above the top of the aquifer, but confinement does not guarantee protection. Improperly constructed wells, fractures, or connected formations can still create pathways. Operators should know which aquifer each source uses and avoid assuming depth alone makes a source secure.
Well records help explain what cannot be seen from the floor of the wellhouse. They show depth, casing, screen, seals, and the water-bearing zone. Keep those records where staff can find them during repairs or an emergency. If the field condition does not match the record, note the difference. Do not guess which drawing is right. A contractor or engineer may need to confirm the actual construction.
Key point: use the approved source assessment and well record, not appearance, to understand vulnerability.
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Groundwater Wells, Pumps and Treatment Fundamentals
This page comes from the course. It covers aquifers and wells, wellhead protection, well pumps and controls, water levels and well performance, groundwater quality, treatment and disinfection, sampling and troubleshooting, one step at a time, with short knowledge checks and a certificate of completion.
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