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This paper gives step-by-step instructions for assessing aquatic selenium hazards associated with mining.

The present study is an attempt to investigate the impact of intensive agriculture and horticulture activities on the hydrogeological and hydrochemical regime in a watershed in Central India. The study area covers 137 km2 and the land use land cover (LULC) study shows that 39.72% area is agri-horticulture land, and 29.78% of the land is covered with other vegetation. Groundwater budgeting is aimed to estimate stage of groundwater development and to examine the contribution of different competing users (domestic, agriculture and industries) on groundwater usage. The groundwater budgeting results show that the stage of groundwater development is 100.26%, thus the study area falls under the over-exploited category as per GEC 2015 norms. The groundwater quality indicates the elevated concentration of nitrate (>45 mg/L) in 41% samples of pre-monsoon season and 80% samples in the post-monsoon season. The elevated concentration of nitrate in groundwater samples of the post-monsoon season indicates the contamination due to the non-point sources like excessive use of fertilizers in horti-agriculture. The sodium adsorption ratio (SAR) values indicate that groundwater is suitable for irrigation. However, physico-chemical water quality results show that 74% samples of pre-monsoon and 85% samples of the post-monsoon season are found unsuitable for drinking as compared to acceptable limits of drinking water specification BIS 10500:2012. The study area needs intervention measures both on the supply side and demand side to bring the development stage and water quality to safer limits. Long term mitigation strategies for the revival of the natural streams should also be adopted to increase water availability in the study area. Precision agriculture, promotion of organic farming, minimization of water use, soil amendments for soil moisture retention and prevention of the runoff must be included in the management practices to improve the health of the watershed and for the long term sustainability.

High concentrations of arsenic in ground waters in West Bengal and Bangladesh have become a major cause for concern in recent years. Given the enormity and the severity of the problem of arsenic poisoning, a task of evaluating the commercially available arsenic detection field kits for their capabilities was undertaken. In the light of the findings, generic specifications were recommended which could form the basis for indigenous manufacture of these kits in the arsenic affected countries. This article presents the results of the laboratory and field evaluation conducted in Bangladesh and West Bengal of five arsenic testing field kits. The salient features of the kits, their merits and limitations have been brought out. Based on the criteria of kit design, quality of chemicals used, colour comparator charts, detection range, time required for analysis, cost etc., a comparative ranking of the kits has been made to facilitate the choice of the kit to meet specific requirements.