The life of the drill is due to many factors, as well as the problems it may present during its operation.

The main factors are the construction of the drilling, the quality of the aquifer and the correct choice of the pump. During the construction, the drilling technique, the quality of the construction materials (pipes, gravel filter), the correct placement of the filters, the good development of the drilling and the selection of the appropriate pumping unit for the correct exploitation of the drilling should be taken into consideration.

E.g. if the pipes are not resistant to the composition of the aquifer, the filters are placed at the wrong depth, no suitable or no gravel filter is used, the pump supply is greater than the capacity of the aquifer, etc.

The problems that drilling can present are:

  • Reduction of pumping supply due to clogging of the filters, by mechanical (clay, sand, etc.) or chemical (salts) causes.
  • The blockage of gravel filters from fine sand or clay.
  • The regular destruction of the submersible pump, due to its malfunction.
  • Corrosion or destruction of piping due to acidic aquifers.
  • Another cause that can clog filters and aquifer pores are iron bacteria and manganese bacteria.

The construction of a drilling according to the rules of science and technology, reduces the adverse effect of the above actions and prolongs its life.

For older drillings that present a problem during their use, we suggest the following tasks, from which a selection will be made for the best and safest result.

After the assessment of the problem, the method of improving the drilling efficiency will be selected,

  1. Check the existing submersible pump by an electrician.
  2. Submersible drainage sump pump.
  3. Submersible pump test in laboratory.
  4. Drilling control with level gauge for resting level and drilling bottom depth
  5. Check the drilling with an underwater camera to determine the condition of the pipes.
  6. Cleaning drilling development by mechanical and chemical means. (work permit)
  7. Drilling pipeline of smaller diameter than the existing one. (work permit)
  8. Test pumping to determine the exploitable flow and loss of drilling load.
  9. Results report.

In many years of drilling, it is possible for a cleaning to be fatal, not improve its performance and, worst of all, destroy it.

Some ways to clean and develop the drill are:

  • Clean the filters inside the drill with brushes to remove the salts inside the filters.
  • Wash by spraying water perpendicular to the filters at a pressure of up to 10 atm.
  • Dry washing with hydrochloric acid content 25-35%.
  • Cleaning using a plunger.
  • Use of sulfanilic acid solution to remove organic or aluminous material in the blockage of filters.
  • Use of polyphosphates to dissolve crust of sludge, clay and compounds of iron and manganese. Airlift washing should follow.
  • Use of chlorine for washing from gelatinous deposits of iron bacteria.

The use of all mechanical and especially chemical treatments must be done by specialized personnel, with the appropriate clothing and precautions, so as not to suffer burns or poisoning from the acids and toxic gases that emerge from the drilling.

If the results of cleaning the filters are not satisfactory or are required to be done frequently, then the drilling is abandoned and a new one is opened at a distance of not less than 10m.