==Construction, operations and maintenance==
[[Image:Emas2.png|thumb|right|250px|Setting up the light-weight drill tower.]]
[[Image:Emas4.png|thumb|right|250px|Installing the lever, used to move the drill stem up and down.]]
Soft Clay is the easiest to drill, is suitable conditions 40 meters can be drilled in this material in one single day. For every meter, between 10 and 20 litre of water is needed, inlcuding washing. For a 20 meter well, one or two barrels of water are enough.
No temporary casing is used. Upon reaching the desired depth, drilling fluid is removed from the hole by injecting progressively lower density mud. If unstable layers are present, however, this diluting can make the well collapse before it can be cased. In such cases it may be better to case the well with mud in it and evacuate the mud afterwards by pouring or injecting water into the casing (backwashing).
The complete rig can be built locally in about any arc-welding workshop, using only materials found in ordinary hardware stores.
{|border="1" cellspacing="0"
|-
! scope="col" |[[Image:Emas2.png|thumb|right|250px|Setting up the light-weight drill tower.]]
! scope="col" |[[Image:Emas4.png|thumb|right|250px|Installing the lever, used to move the drill stem up and down.]]
! scope="col" |[[Image:Emas3.png|thumb|right|250px|Drilling in process: one person operates the lever, one person guides the drill stem and rotates it, the third person operates the mud pump.]]
|-
|[[Image:Emas5.png|thumb|right|250px|The mud pump in close-up.]]
|[[Image:Emas6.png|thumb|right|250px|The well screen, slits cut with saw, end capped. Later, a sock is pulled around the screen.]]
|[[Image:Emas9.png|thumb|right|250px|After the well screen is put in the well, the well is developed by a special tool.]]
|}
The complete rig can be built locally in about any arc-welding workshop, using only materials found in ordinary hardware stores.
[[Image:Emas3.png|thumb|right|250px|Drilling in process: one person operates the lever, one person guides the drill stem and rotates it, the third person operates the mud pump.]]
[[Image:Emas5.png|thumb|right|250px|The mud pump in close-up.]]
==Costs==
[[Image:Emas6.png|thumb|right|250px|The well screen, slits cut with saw, end capped. Later, a sock is pulled around the screen.]]
[[Image:Emas9.png|thumb|right|250px|After the well screen is put in the well, the well is developed by a special tool.]]
An EMAS drilling rig, fit to drill holes up to 30 m deep, can be built in Bolivia for about US$ 600 - 800. This includes the tower, mud pump and all essential non-common tools to operate and maintain it.
