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Wells as deep as 90 meters can be drilled within 3-4 days without any machine employment and exclusively through the use of manual labor. Depths up to 100 m have been reached with the EMAS method. Most regions of South America (loam and sandy soils) are geologically suitable for this drilling method (predominantly rinsing or suction drilling).
This technique is suitable for weakly cohesive sands and silts. It adapts best to loamy soils, consolidated materials and light rock. In sticky clays, the mud injection orifices in the bit can get blocked. In pure coarse sands, progress may be slowwhen only washing is used: the space between the drill stem and the well walls is relatively large, in relation to the slender drill stem, which makes for a slow upward flow. Sand may sink faster than it can be lifted out with the drilling fluid. In such conditions, it may be beneficial is easy to (temporarily) switch change from washing to suction drilling, by changing the handle. An example is shown in [http://blip.tv/file/2445078 this movie]. A universal drill bit was designed which is very good for washing and suction, and which cannot get plugged by stones. The borehole stays open by water pressure. To prevent collapsing fluid-drilled boreholes must be kept full of water during the entire drilling and well installation process. For a sludging technique20 m well, one or two barrels are needed, or about 10-20 liters per meter.
- Adaptable to other countries and regions with similar soil conditions.<br>
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- Generally limited to sandy soils. Soft and soft clay will be penetrated only very slowly and coarse gravel and other highly permeable materials (cracks in the formation) cause loss of working water and cannot be drilled. The borehole stays open by water pressure. To prevent collapsing fluid-drilled boreholes must be kept full of water during the entire drilling and well installation process.<br>
- Enough working water needs to be available on the drilling location. <br>- Leaving the borehole open during the night has a risk of collapsing.<br>
- Slower than motorized drilling<br>
[[Image:Emas4.png|thumb|right|150px|Installing the lever, used to move the drill stem up and down.]]
Soft Clay is the easiest to drill, sometimes we drill in this material 40 meters in one single day. It is true that when we hit a cave some drill liquid runs away. But that happens In 100 well one time and never made drilling impossible. We need for every meter between 10 and 20 Liters of water, including washing. For a 20 meter well 1 or two barrels are enough. Is that much?
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