[[Image:Rota_sludge_well_drilling_icon.png{{Language-box|right]]english_link= Jetting - EMAS well drilling is a method for drilling small-diameter tube wells by hand, up to 100 m deep. The 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 not, however, penetrate hard original rock or boulders (e.g. ancient river beds underground). The usual diameter of the tube well is 37 mm.| french_link= Coming soon | spanish_link= Coming soon | hindi_link= Coming soon | malayalam_link= Coming soon | tamil_link= Coming soon | swahili_link=coming soon | korean_link= Coming soon | chinese_link=水力噴射－EMAS方法 | indonesian_link= Coming soon | japanese_link= Coming soon }}
[[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.]]
__NOTOC__The EMAS method of manual drilling is a hybrid between [[Jetting - general|Jetting]], [[Percussion - general|percussion]], and [[Sludging - Rota sludge|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.
[[Image:Emas.jpg|thumb|right|150px|Drilling a well in Colombia with the The EMAS drilling method.]][[Image:Emas1.png|thumb|right|150px|All was developed by the equipment needed easily fits on a small hand-cart.]][[Image:Emas2.png|thumb|right|150px|Setting up the light-weight drill tower.]][[Image:Emas4.png|thumb|right|150px|Installing the leverEscuela Móvil de Agua y Saneamiento (Mobile School for Water and Sanitation, used to move the drill stem up and down.]][[Image:Emas3.png|thumb|right|150px|Drilling EMAS) in process: one person operates the lever, one person guides the drill stem and rotates it, the third person operates the mud pumpBolivia.]][[Image:Emas5.png|thumb|right|150px|The mud pump Project leader of EMAS 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 Bolivia is put in the wellWolfgang Eligius Buchner, the well is developed by a special tool.]][[Image:Emas8.png|thumb|right|150px|Putting born 1957 in an EMAS flexi-pump.]][[Image:Emas7.png|thumb|right|150px|Wetting the cement for the pump baseHolzkirchen bei München.]]
EMAS was established in 1993, and has provided training for about 130 independent well builders in its branches in San Julian (1994) and in Puerto Pérez (1997). 20 students have been able to graduate from the licensed craftsman course. The well builders in Bolivia have founded a well builder organization.
During a three-month education, agricultural workers are trained to independently drill wells, build sanitary installations and market their skills in their local area depending on demand.
The need for large financial investments for well drilling and the building of line systems has traditionally prohibited the construction of large scale potable water systems in rural areas. Wolfgang Buchner adapted already accepted suction - and rinsing drilling methods to local conditions.
==History and social context==The EMAS drilling method was developed by is not only the name of the Escuela Móvil de Agua y Saneamiento (Mobile School mobile school for Water water and Sanitationsanitation, EMAS) in Bolivia. Project leader 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 EMAS in Bolivia is Wolfgang Eligius Buchnerhand and foot pumps, born 1957 in Holzkirchen bei Münchenand 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 was established in 1993, method. Most regions of South America (loam and has provided training sandy soils) are geologically suitable for about 130 independent well builders in its branches in San Julian this drilling method (1994predominantly 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 pure coarse sands, progress may be slow when only washing is used: the space between the drill stem and the well walls is relatively large, in Puerto Pérez (1997)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. 20 students have been able In such conditions, it is easy to graduate change from washing to suction drilling, by changing the licensed craftsman coursehandle. The well builders An example is shown in Bolivia have founded a well builder organization[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.
During 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 three-month education20 m well, agricultural workers one or two barrels are trained to independently drill wellsneeded, build sanitary installations and market their skills in their local area depending on demandor about 10-20 liters per meter.
The need for large financial investments for well drilling and the building of line systems has traditionally prohibited the construction of large scale potable water systems in rural areas. Wolfgang Buchner adapted already accepted suction - and rinsing drilling methods to local conditions.
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.{| border="1" cellpadding="5" cellspacing="0" align="center" |-! width="50%" style=Suitable conditions ="background:#efefef;" | Advantages! style="background:#f0f8ff;" | Disadvantages{{procontable | -pro| valign="top" | - Very quick in fine and medium sand formations.<br>
- Very simple and cheap equipment. <br>
- No need for machines. <br>
- No need for motor-powered mud pump and tower.<br>
- Can work below the groundwater table. <br>
- uses Uses non-corrosive, easily accessible and processable materials (PE and PVC). <br>- less endangerment of the workers than when digging an open well shaft. <br>- low Low maintenance costs <br>- low Low cost (approx. US-$ 6 per meter of depth inclusive including hand pump) allows for a surface covering potable water supply in the rural area. This is approx. about 10 times more economical than the least expensive existing commercially available method. <br>- adaptable Adaptable to other countries and regions with similar soil conditions.<br>| convalign="top" | - Generally limited to sandy soils and soft clay. - Enough working water needs to be available on the drilling location. <br>- Does not penetrate rockLeaving the borehole open during the night has a risk of collapsing.<br>- slower Slower than motorized drilling<br>}|}
Wells as deep as 90 ===Construction, operations and maintenance===Soft Clay is the easiest to drill, is suitable conditions 40 meters (approx.270 feet) can be drilled within 3-4 days without any machine employment in this material in one single day. For every meter, between 10 and exclusively through the use 20 litre of manual laborwater is needed, inlcuding washing. Depths up to 100 m have been reached with the EMAS method. Most regions For a 20 meter well, one or two barrels of South America (loam and sandy soils) water are geologically suitable for this drilling method (predominantly rinsing or suction drilling)enough.
This technique adapts best to loamy soils, consolidated materials and light rock. In sticky clays, Drilling is continuous: the mud injection orifices in drill bit is normally not removed from the bit can get blockedborehole until it is finished or work is interrupted. In pure coarse sands, progress may be slow: the space between As a portion of the drill stem and the well walls is relatively largeentered, another length of ¾” (19 mm) metal pipe with reinforced threads is screwed on. Drilling fluid (mud, in relation to a suspension of ordinary clay or bentonite with an adequate density) is pumped down through the slender drill stem, which makes for using a slow upward flowhand-operated mud pump. Sand may sink faster than it can be lifted out with the The drilling fluidcomes back up around the drill stem, carrying broken-up material. In such conditionsSand and small stones settle in a settling area dug in the ground, it may be beneficial to (temporarily) switch to a sludging techniqueand the mud is recycled through the pump.
Percussion action is performed by lifting the drill with a lever, mounted on the drilling tower, and letting it fall down. Moreover, the drill is rotated half-turns in both directions, enhancing the grinding action of the bit.
==Technical specification==The resulting hole diameter is about two inches, and wells are cased with cheap 1 1/2” (39 mm) PVC pipe. This can accommodate a 1 1/4” PVC piston pump, but if required, the upper portion of the well (down to about 1 m below the lowest expected water table) can be reamed to accommodate larger diameter pumps.
====Operation====Drilling is continuous: As the entire drill bit stem is normally not removed from metallic, the borehole until it is finished or work is interrupted. As a portion weight of the drill stem is entered, another length of ¾” (19 mm) metal pipe increases linearly with reinforced threads is screwed on. Drilling fluid (muddepth, a suspension of ordinary clay or bentonite with an adequate density) is pumped down through so the drill stem using a hand-operated mud pump. The drilling fluid comes back up around deeper the drill stemwell, carrying broken-up material. Sand and small stones settle in a settling area dug in the groundheavier the stroke, and the mud but stroke length is recycled through limited to about 30 cm by the pumplever.
Percussion action No temporary casing is performed by lifting used. Upon reaching the drill with a leverdesired depth, mounted on drilling fluid is removed from the drilling towerhole by injecting progressively lower density mud. If unstable layers are present, however, and letting this diluting can make the well collapse before it fall downcan be cased. Moreover, In such cases it may be better to case the drill is rotated half-turns well with mud in both directions, enhancing it and evacuate the grinding action of mud afterwards by pouring or injecting water into the bitcasing (backwashing).
The resulting hole diameter is about two inches, and wells are cased with cheap 1 1/2” (39 mm) PVC pipe. This can accommodate a 1 1/4” PVC piston pump, but if required, the upper portion of the well (down to about 1 m below the lowest expected water table) complete rig can be reamed to accommodate larger diameter pumps. As the entire drill stem is metallic, the weight of the drill increases linearly with depth, so the deeper the well, the heavier the stroke, but stroke length is limited to built locally in about 30 cm by the lever. 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, howeverany arc-welding workshop, 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 using only materials found in it and evacuate the mud afterwards by pouring or injecting water into the casing (backwashing)ordinary hardware stores.
====Maintenance====
{|style="border-style: solid; border-width: 1px 1px 1px 1px; text-align: center; background-color: #efefef" align="center" width="70%" |-! scope=Manufacturing ="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.]]|}
The complete rig can be built locally in about any arc-welding workshop, using only materials found in ordinary hardware stores. ==Cost=Costs===
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.
That price is calculated in 3 parts. Taking 6$ as basis, 2$ are for the material and hand pump (a hand pump is normally included in a well deeper than 20 meters), 2$ are for the wage of the two drillers (including also the maintenance of the equipment) and 2$ in the creation of
a reserve fund in case there is no water or not enough water found, salty water found or a drilling mistake is made such as a broken drill stem, the wrong filter sleeve, etc.
Normally, for the price of 5$ a 1 year warrantee is given in case that the sand remains after 4 weeks use.
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 has produced a set of DVDs which cover, among others, EMAS drilling and other low cost water supply techniques. Contact Wolfgang Buchner in Bolivia at [email protected] or [email protected] 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 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 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 by Wolfgang Buchner.==Manuals==* Collection of [https://vimeo.com/emas EMAS movies] on different EMAS subjects.
{|style==Movies=="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>}}|}
==External links==Other resources====* The Technology Demonstration Center EMAS works with EMAS Jetting. See [[Technology Demonstration Centers]]* [http://www.emas-international.de/englishindex.php?id=51&L=3 EMAS] on well drilling. * [http://index_epaulcloesen.htm www50webs.emascom/In-internationalEN.dehtm EMAS drilling by Paul Cloesen] .* General info on well drilling Rural Water Supply Network, [http://www.rwsnrural-water-supply.org wwwnet/en/implementation/manual-drilling/emas-drilling article on EMAS drilling].rwsn.org*[[Solution_of_the_week_10|Akvo solution of the week 10]]*[[Solution_of_the_week_11|Akvo solution of the week 11]]
==References=Acknowledgements===* This article is based on an [http://www.paulcloesen.50webs.com/In-EN.htm article ] by [http://www.paulcloesen.50webs.com/ Paul Cloesen], and on material from [http://www.emas-international.de/english/index_e.htm wwwindex.php?id=51&L=3 emas-international.de]
