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Most of the drinking water supply in rural Bangladesh comes from groundwater collected using shallow tubewells. The tubewells, usually shallow because of the increased cost involved in deeper tubewells, have been installed by local drillers. A Sediment Color Tool was developed, with input from local drillers, that associated the arsenic concentration with specific sediment colors, in order to help the drillers install safe tubewells. This tool was digitized into the phone application, ASMITAS, to reduce subjectivity in sediment color determination due to human error or surrounding conditions, when used with a color sensor. The purpose of this study was to carry out a preliminary assessment of the application performance and usability, and the results provided by the application for color identification. 35 sediments were used and assigned into 4 different data sets to allow for comparison. Two data sets were assigned a Munsell color manually, while two were assigned the Munsell Soil Color (or Red-Green-Blue color) through use of the digital app. The sensor, the Nix Color Sensor Pro 2, was validated through a literature review and is considered accurate in identifying the color of the soil sediments. The data sets were compared based on the Delta E 2000 formula to determine the color difference between the data sets. The most relevant result of this method was between the Red-Green-Blue that the Nix Sensor originally provided to the application versus the closest matching Munsell code that the application could provide. It showed that the library from which the Munsell color was drawn was not yet expansive enough to accurately identify all sediments that may be scanned. Cyan-Magenta-Yellow-Black color comparisons were made to ascertain which aspects of the color are the most difficult to identify. It was found that both the sensor and the human eye had difficulties in identifying differences in the yellow percentage of several of the samples. The results showed that, Största delen av dricksvattenförsörjningen i lantlig Bangladesh kommer från grundvatten som samlas in med rörbrunnar. Rörbrunnarna, som vanligtvis är grunda som en följd av kostnaderna, har installerats av lokala borrare. Under 2007 antogs det att färgen på sedimentet i vilket rörbrunnarna placeras ger en indikation på arsenikens koncentration. Därför utvecklades Sediment Color Tool med input från de lokala borrarna. Verktyget vidareutvecklades till en digital app, ASMITAS, för att minska subjektiviteten i markfärgbestämning på grund av mänskliga fel eller omgivande förhållanden. Syftet med denna studie var att utvärdera applikationens prestanda i detta stadie av dess utveckling och färgidentifiering som genomförts av applikationen. 35 sediment användes i första bedömningen och klassificerades fyra gånger i fyra olika datamängder för att möjliggöra jämförelse. Två datamängder tilldelades en Munsell Soil Color manuellt, medan två tilldelades sin färg genom användning av den digitala appen. Sensorn som användes, Nix Color Sensor Pro 2, validerades genom en litteraturöversikt och anses vara korrekt när det gäller att identifiera färgen på sediment. De fyra datamängderna jämfördes visuellt med användning av färgbrickor. De jämfördes baserat på DE2000-formeln för att bestämma färgskillnaden mellan datamängden. Det mest avslöjande resultatet med denna metod var mellan dem två digitalt förvärvade datamängderna. Resultatet föreslår att referensbiblioteket i ASMITAS, från vilket matchen togs, ännu inte var tillräckligt stort för att identifiera alla sedimentprover noggrant för att ej vara märkbar för det mänskliga ögat. Cyan-Magenta-Gul-Svart jämförelser gjordes för att se vilka aspekter av färgen som är svårast att identifiera. Resultaten visade att både sensorn och det mänskliga ögat hade svårigheter att identifiera skillnader i den gula procentandelen av flera av proverna och sedimentfärg

Nearly 90% of the estimated 10 million tubewells in Bangladesh are installed privately by local drillers for rural drinking water supplies in Bangladesh. The awareness of local drillers on elevated Arsenic (As) concentrations in tubewell water at shallow depths have made them change their practice of installation of tubewells. Using the visual color attributes of the shallow sediments (<100 m) and content of dissolved iron, generally associated with high As concentrations, the local drillers presently install community tubewells at depths targeting red/brownish or off-white sediments. This study recognizes the local tubewell drillers as important stakeholder in the business of tubewell installation. A Sediment Color Tool has been developed to enhance the local driller’s capacity to identify the As-safe aquifers that would bring significant change to reduce As exposure and scale-up safe water access in rural Bangladesh., Part of proceedings: ISBN 978-1-138-02941-5 QC 20170531QC 20221220

Tubewells installed by local drillers, provide access of drinking water in rural Bangladesh. Significant proportion of these wells contains arsenic (As) above the WHO guideline and the Bangladesh Drinking Water Standard. Various attempts for mitigation at household and community scale have resulted in limited success, but through the local driller's initiatives, the tubewells are the source of priority drinking water supply. We have developed a concept of Sustainable Arsenic Mitigation (SASMIT) to identify and target the safe aquifers through detailed hydrogeological studies for scientific validation of the water quality with respect to the color of the shallow sediments as perceived by local drillers. Together with water quality monitoring, we have also targeted the Intermediate Depth Aquifers (IDA) for providing As-safe and low manganese (Mn) water. SASMIT intervention logic also considered the relevant socio-economic scenario, such as household distribution, poverty issues and available safe water access for prioritizing safe well installation., QC 20141217

Arsenic (As) poses the greatest hazard towards drinking water quality in Bangladesh. Tubewell drinking water is one of the main sources for household based water options in rural Bangladesh. Our study area is in Matlab Upazila, in Bangladesh. The overall objective of this research and the SASMIT project is to develop a community based initiative for sustainable As mitigation by developing a sediment color based tool for the local drillers prioritizing on the hydrogeological and biogeochemical investigations. For this purpose we analyzed different depth colored sediments and water for find out the sustainable low Arsenic contaminated aquifer., QC 20150604