Water supply in rural northeast areas of India and neighbouring Bangladesh is usually a single source of water for each village. Rural villagers, often lacking electric power, rely on this common village well as their only source of drinking water. If this well has a high level of arsenic, the entire village suffers. Instances of disease related to long-term arsenic exposure are relatively common.
For many years, the typical village water source was surface water (generally a lake or river). The waterborne diseases typical of untreated surface water were common. In the 1970s and 1980s, with funding from a number of international aid groups, millions of tube wells (typically of the order 100 feet deep) were drilled to provide what was thought to be a clean water source for rural villagers. Unfortunately for the villagers, in many cases one type of illness was simply traded for another. By the 1990s, it was recognised that the aquifer underlying most of northeast areas of India and neighbouring Bangladesh is high in naturally occurring arsenic. Arsenic levels in excess of 100 ppb are relatively common. The result is that millions of people in this area now exhibit the symptoms of chronic arsenic poisoning: skin lesions, neurological disorders and cancers.
Governmental agencies and various aid groups have struggled to find an adequate solution to the problem for years. Drilling deeper wells (of about 1000 feet) will avoid the arsenic contaminated aquifer, but this is too expensive and time-consuming to be a universal solution. Most of the treatment technologies common in the US are not applicable because of their relatively sophisticated control systems and occasional backwashing requirement.
The Isolux Technologies Division of MEL Chemicals, Inc. has developed Isolux technology for arsenic removal using its patented zirconium hydroxide media. MEL Chemicals, Inc. has been producing zirconium chemicals at its facility in Flemington, NJ for over 50 years. In combination with its British affiliate, MEL Chemicals, Ltd, it is the world's largest producer of zirconium chemicals. In addition to being NSF Standard 61 certified, Isolux technology has a number of advantages that make it a possible solution for rural villages in India: (1) it does not require backwashing or ‘fluffing' of the media bed; (2) it does not use any external controls; (3) all of its systems are designed around a cartridge replacement concept (cartridges can easily be replaced by an unskilled person in less than an hour); and (4) Isolux's 20-gpm unit which holds four arsenic removal cartridges appears to be an ideal size for most village wells.
In late 2008, the Indian State of Bihar awarded a contract to DNA Infrastructure Pvt. Ltd (an Indian engineering company) for arsenic treatment systems for a number of rural villages. DNA Infrastructure approached Isolux to provide their 20-gpm units for this project. Between the end of 2008 and the beginning of 2009, a total of 39 rural villages in the Indian state of Bihar were provided with an arsenic-free drinking water source using Isolux technology combined with a solar-electric powered well pump.
Despite years of effort and many projects including that described here, the problem of arsenic contaminated groundwater in northeast India and Bangladesh remains one of the world's most severe public health crises. As a US company, MEL Chemicals has found that it is almost impossible to independently develop and implement projects in India or in most Asian countries. Differences in language, customs and business practices are very difficult to surmount, particularly when dealing with a relatively new technology such as arsenic adsorption. The key to success is to find a local partner such as DNA Infrastructure who can provide the bridge to successfully resolve the problem.