Question 1

How do you know when a well is developed?

Accepted Answer

Development is a continual process that improves the well yield and clarity with time.  The length of time to develop a well depends on many factors, including the method – percussion, augering, jetting, mud rotary, etc.  Well development is the process of restoring the formation to the pre-drilling conditions – which is the ideal condition.  If the compaction can be relieved, if the smearing can be removed and the fines adjacent to the well bore removed, the well will achieve near 100 percent efficiency and development.

Other factors include the physical nature of the formation itself.  Poorly sorted, fine-grained materials take much longer than well-sorted granular sediments. The size of the screen slots compared to the size of the grains adjacent to the screen is an important factor. If a large percentage of the grains (clays and silts) near the borehole will fit through the screen slots, the well will take longer to develop.  Ideally, the amount of material that settles out of the development water in a 5-gallon bucket should be less than a teaspoon per gallon.

Question 2

Do rock wells need to be developed?

Accepted Answer

Yes.  Particles of rock and sediments will smear and plug the permeable parts of the borehole.  Layers of silts and clays need to be removed from the borehole wall to achieve development.  Generally, rock wells, with or without smears, will develop faster than unconsolidated sediments.

Question 3

How often does the check valve ball become sand locked during development?

Accepted Answer

Rarely. If you take a break from surging, the check valve will hold the water in the riser pipe until stroking resumes.  Sand will become suspended at the next fast downstroke as new water enters the bottom of the tool. If the check valve appears to be leaking there may be something in the ball seat that is preventing the ball from seating (e.g., grass or leaves). The inventor of the QWD once had a small frog in the check valve.

Question 4

How long will the Qwater Well Developer wiper last?

Accepted Answer

We do not know. We have never worn out a polyurethane wiper.  Some are more than five years old. The Qwater Well Developer tool is priced to be disposable so that contamination would not be carried from well to well.

Question 5

Can the Qwater Well Developer be used with well redevelopment chemicals such as acids and chlorine?

Accepted Answer

Technically, yes.  All the parts are made of PVC, polyurethane or stainless steel, and should not be affected by redevelopment chemicals such as acids or chlorine.  However, pure organic solvents (fuels, TCE, PCE, etc.) may soften the PVC parts if they are in contact for an extended period of time.

FAQ