Changes

[[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 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.