Well rounded sand or gravel that is placed between the formation and the screen.
Monitoring well filter sand.
Well pack gravel is used for deep bed in ground wells to form a barrier between the screens and the natural deposit of the land which in turn allows for the well to provide very clean water.
Previous versions of the document are.
The annular space above the sand pack is then sealed to prevent surface.
Selecting the appropriate sand pack can be a challenge.
Piezometer 4 2 1 1 2 6 bentonite seal filter pack of sand figure 1.
If the well is completed with a screen as opposed to an open hole finish in hard rock then the screen usually is surrounded by a sand pack placed by the driller.
Installation of a filter pack and screen may not be necessary for wells completed in competent bedrock.
The most recent version is presented in the top row of the table.
Thomas kwader presents some guidelines for making your choice.
The space between the screened section and borehole is backfilled with filter sand typically fraction silica sand.
This table shows changes to this controlled document over time.
Mounded bentonite soil mixture well screen well cap riser or stand pipe unslotted soil surface unlined bore hole lined bore hole.
Generally a well functions as a monitor or as a pumping or production well.
Wells designed to monitor groundwater to evaluate the changes in the physical chemical and biological properties of water.
It helps to prevent sediment from entering the well.
January 29 2013 revision history.