The picture shows one of several basins in a coffee processing facility („despulpadora“) in Guatemala.
Some small scale coffee farmers organized themselves in a „cooperativa“ to build the facility. The coffee beans will get rid of their pulp and fermented before drying.
Before the facility was build each farmer processed the beans in much simpler machinery on his own lands and the contaminated water (in spanish „agua miel“ meaning honey-water) just ran off over the surface and went directly into soil, river and ground water.
The new facility provides at least rudimentary water treatment for example by several storage reservoirs and the application of chalk. It is expected that the facility by now (2015) gained the farmers the investment cost!