[[Image:Treadle_pump_icon.png{{Language-box|right]][[Image:Emas0.jpg|thumb|right|150px|Emas well drilling]][[Image:Emas.jpg|thumb|right|150px|Drilling a well in Colombia with the english_link= Jetting - EMAS method.]][[Image:Emas1.png|thumbfrench_link= Coming soon |rightspanish_link= Coming soon |150pxhindi_link= Coming soon |All the equipment needed easily fits on a small hand-cart.]][[Image:Emas2.pngmalayalam_link= Coming soon |thumbtamil_link= Coming soon |right|150px|Setting up the light-weight drill tower.]][[Image:Emas4.png|thumb|right|150px|Installing the lever, used to move the drill stem up and down.]][[Image:Emas3.png|thumb|right|150px|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|150px|The mud pump in close-up.]][[Image:Emas6.png|thumb|right|150px|The well screen, slits cut with saw, end capped. Later, a sock is pulled around the screen.]][[Image:Emas9.png|thumb|right|150px|After the well screen is put in the well, the well is developed by a special tool.]][[Image:Emas8.png|thumb|right|150px|Putting in an EMAS flexi-pump.]][[Image:Emas7.pngswahili_link=coming soon |thumbkorean_link= Coming soon |rightchinese_link=水力噴射－EMAS方法 |150pxindonesian_link= Coming soon |Wetting the cement for the pump base.]]japanese_link= Coming soon }}
__NOTOC__[[Image:Icon_EMAS_drilling.png|right|80px]][[Image:Emas.jpg|thumb|right|200px|Drilling a well in Colombia with the EMAS method.]][[Image:Emas1.png|thumb|right|200px|All the equipment needed easily fits on a small hand-cart.]]
The EMAS method of manual drilling is a hybrid between [[Jetting - general|Jetting]], [[Percussion - general|percussion]], and [[Sludging - Rota Sludgesludge|rotary]] drilling. A manually powered mud pump is used, and the drill stem is turned through 90 degrees at the end of each stroke. It permits to drill through all kinds of loose soils, as well as consolidated materials and light rock. It will not, however, penetrate hard original rock or boulders (e.g. ancient river beds underground). The usual diameter of the tube well is 37 mm.
==History and social context==
The EMAS drilling method was developed by the Escuela Móvil de Agua y Saneamiento (Mobile School for Water and Sanitation, EMAS) in Bolivia. Project leader of EMAS in Bolivia is Wolfgang Eligius Buchner, born 1957 in Holzkirchen bei München.
EMAS is not only the name of the mobile school for water and sanitation, but also a whole technical and social concept of water and sanitation which includes rain water harvesting, solar water heaters, windpower, hydraulic rams, water treatment, small tanks and sinks, a variety of hand and foot pumps, and ferrocement tanks.
===Suitable conditions ===[[Image:Emas0.jpg|thumb|right|200px|Emas well drilling]]
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 a sludging techniquesuction 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 20 m well, one or two barrels are needed, or about 10-20 liters per meter.
{{procontable | proborder="1" cellpadding="5" cellspacing="0" align="center"|-! width="50%" style="background:#efefef;" | Advantages! style="background:#f0f8ff;" | Disadvantages|-| valign="top" | - Very quick in fine and medium sand formations.<br>
- Very simple and cheap equipment. <br>
- No need for machines. <br>
- Low cost (approx. US-$ 6 per meter of depth including hand pump). This is about 10 times more economical than the least expensive commercially available method.<br>
- Adaptable to other countries and regions with similar soil conditions.<br>
|convalign= "top" | - 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>
|}}
==Technical specification=Construction, operations and maintenance===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.
====Operation====
Drilling is continuous: the drill bit is normally not removed from the borehole until it is finished or work is interrupted. As a portion of the drill stem is entered, another length of ¾” (19 mm) metal pipe with reinforced threads is screwed on. Drilling fluid (mud, a suspension of ordinary clay or bentonite with an adequate density) is pumped down through the drill stem using a hand-operated mud pump. The drilling fluid comes back up around the drill stem, carrying broken-up material. Sand and small stones settle in a settling area dug in the ground, and the mud is recycled through the pump.
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).
====Maintenance====
====Manufacturing ====
The complete rig can be built locally in about any arc-welding workshop, using only materials found in ordinary hardware stores.
{|style="border-style: solid; border-width: 1px 1px 1px 1px; text-align: center; background-color: #efefef" align="center" width="70%" |-! scope="col" |[[Image:Emas2.png|thumb|center|200px|Setting up the light-weight drill tower.]]! scope="col" |[[Image:Emas4.png|thumb|center|200px|Installing the lever, used to move the drill stem up and down.]]! scope="col" |[[Image:Emas3.png|thumb|center|200px|Drilling in process: one person operates the lever, one person guides the drill stem and rotates it, the third person operates the mud pump.]]! scope="col" |[[Image:Emas8.png|thumb|center|200px|Putting in an EMAS flexi-pump.]]|-|[[Image:Emas7.png|thumb|center|200px|Wetting the cement for the pump base.]]|[[Image:Emas5.png|thumb|center|200px|The mud pump in close-up.]]|[[Image:Emas6.png|thumb|center|200px|The well screen, slits cut with saw, end capped. Later, a sock is pulled around the screen.]]|[[Image:Emas9.png|thumb|center|200px|After the well screen is put in the well, the well is developed by a special tool.]]|} ===Costs=Cost==
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.
The average well depth in Bolivia is around 27 meters, and costs approx. US$ 180 including an [[EMAS pump|EMAS hand pump]]. This makes a surface covering supply of drinking water possible for municipalities and families in rural areas.
==Country =Field experiences===
The EMAS method is mainly used in Bolivia, Panama, Ecuador, Paraguay, Brazil, Peru, Honduras, Nicaragua, El Salvador, Guatemala, Eritrea and Sri Lanka.
===Manuals
, videos and links===
* EMAS
have has produced a set of DVDs which cover, among others
, EMAS drilling and other low cost water supply techniques. Contact Wolfgang Buchner
on in Bolivia at [email protected] or emas@
ceibo.entelnet.bo if you would like to order a copy
of the movies on DVD. EMAS manual well drilling is a method for drilling small-diameter tube wells by hand. The
movies drilling method is a hybrid between washboring, percussion and rotary drilling. It permits to drill through all kinds of loose soils, as well as consolidated materials and light rock. It will
also be not, however, penetrate hard original rock or boulders (e.g. ancient river beds underground). The usual diameter of the tube well is 37 mm. Movies made
available by Wolfgang Buchner. * Collection of [https://vimeo.com/emas EMAS movies] on
the webdifferent EMAS subjects.
{|style="font-size: 120%"|-|{{#ev:youtube|B9zXHIrsdiw|200|auto|<center>Well drilling - standard <br>EMAS method - part 1</center>}}|{{#ev:youtube|T8SivxJ8LWg|200|auto|<center>Well drilling - standard <br>EMAS method - part 2</center>}}|{{#ev:youtube|mPz4WxQ245c|200|auto|<center>Suction variant to standard EMAS method - part 1</center>}}|-|{{#ev:youtube|qHwReBdKkr8|200|auto|<center>Well drilling - sludging with <br>temporary casing - part 1</center>}}|{{#ev:youtube|EIjSb7-z5fU|200|auto|<center>Well drilling - sludging with <br>temporary casing - part 2</center>}}|{{#ev:youtube|EmB9EFFNKc0|200|auto|<center>Well drilling - sludging with <br>temporary casing - part 3</center>}}|}
==Movies==Other resources====* [http://blipThe Technology Demonstration Center EMAS works with EMAS Jetting.tv/file/2445011 Standard EMAS well drilling, by Wolfgang Buchner]* See [http://www.youtube.com/watch?v=nYNQt36VayM EMAS well drilling, by Wolfgang Buchner, Part 1] (same movie as above)* [http://www.youtube.com/watch?v=7jw1ZY1ccmo EMAS well drilling, by Wolfgang Buchner, Part 2Technology Demonstration Centers]* [http://emas.blip.tv/ Large collection of EMAS movies on different subjects.]==External Links==* EMAS - [http://www.emas-international.de/english/index_eindex.htm Website of php?id=51&L=3 EMAS ] on EMAS well drilling]. * Article on [http://wwwpaulcloesen.rwsn50webs.chcom/documentation/skatdocumentation.2008In-05-28EN.6936214484 htm EMAS drilling by Paul Cloesen].* Rural Water Supply Network, [http://www.rwsn.ch/prarticle.2005rural-10water-25supply.9856177177net/prarticle.2005-10-26.7220595116en/prarticle.2005-11-15.6127855822implementation/prarticle.2009manual-05-11.3051371225drilling/prarticle.2009emas-05-11.7567765725/prarticle_view drilling article on EMAS drilling]. General *[[http://www.rwsn.ch/prarticle.2005-Solution_of_the_week_10|Akvo solution of the week 10-25.9856177177/prarticle.2005-10-26.7220595116/prarticle.2005-]]*[[Solution_of_the_week_11|Akvo solution of the week 11-15.6127855822/prarticle.2009-05-11.3051371225 manual drilling section of RWSN website].]
==References=Acknowledgements===* This article is based on an [http://www.rwsnpaulcloesen.50webs.chcom/documentation/skatdocumentation.2008In-05-28EN.6936214484 htm article] by [http://geocitieswww.paulcloesen.50webs.com/paulcloesen/ Paul Cloesen], and on material from [http://www.emas-international.de/english/index_e.htm wwwindex.php?id=51&L=3 emas-international.de]