Arsenic Polluted Groundwater and Its Countermeasures in the Middle Basin of the Ganges, Uttar Pradesh State, India ()
1. Introduction
Arsenic contamination of groundwater, in Asia, is seen in the basins of the great rivers, originating in the Himalayan Mountains and the Tibetan Plateau, such as the Ganges River, the Indus River, the Mekong River, the Haw River, and the Yellow River [1], where people depend on the drinking water for groundwater. A thermally altered metamorphic zone in the Higher Himalaya, containing various types of minerals, is considered as the source of arsenic [2].
Arsenic pollution of groundwater in Ganges River basin, West Bengal, India, and Bangladesh is known for long. The detection of the arsenic pollution is in 1982 and 1993, respectively. The investigations and countermeasures have been performed [3-6].
On the other hand, in Mekong River basin, Vietnam, Cambodia and Laos, arsenic pollution was first confirmed around 2000 and countermeasures just began under help such as UNICEF and GIST (Gwangju Institute of Science and Technology) [7,8].
The authors have elucidated the mechanism for arsenic contamination and developed the safe water devices in Bangladesh since 1997 together with the NGO “Asia Arsenic Network” (AAN) [9]. AAN has implemented the Arsenic Mitigation Project with Japan International Cooperation Agency (JICA) in Bangladesh from 1999 until now. The University of Miyazaki has conducted activities for arsenic mitigation in Uttar Pradesh State, India, under a JICA technical cooperation project from 2008 until now, in collaboration with AAN.
Uttar Pradesh State (abbreviated as UP State hereafter) is located at north of India bordering on Nepal, Geographical area of which is about 4700 km2, where two big rivers are running from the northwest to the southeast. The former is the Ghaghara River flowing down from the arsenic affected Terrai plane, and the latter is the Ganges River as shown in Figure 1. The arsenic contamination in UP State was first recognized in 2003 at Ballia District, where both of the Ghaghara and the Ganges are joining.
(a) (b)
Figure 1. (a) Location of Uttar Pradesh; (b) location of project area, Bahraich district.
Arsenic-contaminated tubewell water is detected in the 20 Districts out of 70 Districts in UP State by UP government under the assistance of UNICEF. The government survey was, however, performed only for the government tubewells (GTWs), and private tubewells (PTWs), numerous compared with GTW, were not checked at all. In regard to arsenocosis patients, the number of patient is unknown yet, because the medical examination has not been executed until now.
Our project area is in Bahraich District (See Figure 1(b)), severely arsenic affected one in the above-mentioned 20 Districts. The project is an integrated arsenic mitigation with 3 activities: 1) Raising awareness of villagers for poison of arsenic through a street play, etc.; 2) Identification of arsenocosis patients after training local medical doctors for diagnosis of chronic arsenic poisoning; 3) Installation of arsenic removal unit after checking all tubewells used in the villages.
Though the groundwater of the Ganges medium basin is contaminated with arsenic, few reports [10-12] are obtained. We will, therefore, introduce the situation and mechanism of arsenic contamination of groundwater, obtained from the 1st phase of JICA arsenic mitigation project (2008-2011) as an interim report.
This paper mainly shows the data obtained in the activity (3) mentioned above.
2. Situations of Arsenic Contamination in UP State
Figure 2 shows the ratio of arsenic polluted GTW (As > 50 ppb) in the 20 Districts obtained from the above mentioned government survey. There are 3 severe con taminated Districts: Kehri, Ballia, and Bahraich. The detection of arsenic contamination in Kehri was right after that in Ballia, and 500 of deep wells were installed in Ballia and