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Chris Rollins gravatar image

David -

I am unable to find the reasons for failure often, it is not common (in my limited experience) for Malian consultants to determine the cause of failure or even the precise part that has failed. I struggle with this on all my projects, including vertical construction (inspection and supervision) and PV systems too. I have developed a new inspection sheet format so that they answer what I need to know, instead of me sifting through a 30-page document for 2-3 relevant sections necessary for project progress.

I am working in areas of Gao, Timbuktu, and Douentza, specifically N'kahaka, Kaji, Gouma Rharous, Gossi, Andongo, Niafunke, Araoune. These are conflict areas so I am unable to travel there my self to do a full diagnostic + yield test. Some southern Malians (i.e. Bambara) are also reluctant, so we are limited in our consultant list sometimes.

I am in Bamako today but I travel tomorrow for a week, Douentza and Timbuktu.

Typically I am getting what may be reliable dynamic water level and maximum yield, they are elaborate and done by a hydrologist (or at least with a spreadsheet they got from a hydrologist), but sometimes I wonder if the consultants have even been to the site at all... It is very common for consultant to write 'replace well head with same diameter,' without providing a photo, telling me the diameter, the existing material, the components, etc. I am burning through consultants, not happy with any engineering reports or CAD from 5+ firms so far, if you have recommendations please please provide.

Pumps are often specified (by the consultant in their recommendations) at about 25-50m depth, even on deeper holes (80-100m), so I assume that pump depth is not the problem. Though, it may be a reason for failure in previous installations, where again the consultant does not tell me the reason for the failure.

Unfortunately we (AECOM) installed two Grundfos pumps recently and they failed <6 months. Believe me I have tried to find the reason but I have not uncovered it yet (and I have $2m work right now with one assistant and sites are almost all remote and difficult to access).

Note that we are only drilling holes on a few projects, most of the systems are replacement of existing.