The contamination of groundwater by arsenic is one of the major problems in Nepal. This study was conducted in 20 deep groundwater (>200m) samples of Kathmandu valley to assess the arsenic content of different groundwater zones and to determine the relationship of arsenic with physico-chemical parameters. Samples were collected in the post-monsoon season of 2016. The random sampling method was applied to the collection of water samples.Standard methods as APHA 2005 was followed for the analysis of the water sample.Arsenic concentration showed spatial variation. The maximum concentration of arsenic was found in Central Groundwater Zone at Patan (27040’07.3” and 85019’14”). Karl Pearson’s correlation coefficient revealed that moderate positive correlation of arsenic concentration withelectrical conductivity (μS/cm) (r = 0.58and p =0.01) and turbidity (NTU)(r = 0.67 and p = 0.01). Groundwater consumers of the central zone of the valley are at risk of arsenic-based health issues.

Bhaktapur Municipality has been performing better to keep the city clean. However, scarcity of space for the land filling of the solid waste and proper segregation of waste at the source has been a hurdle for the Municipality. This paper aims to determine solid waste generation rate and to analyze overall situation of solid waste management of Bhaktapur Municipality. However, the data will not represent the seasonal and occasional variations. Additionally, waste from street-sweeping and large-scale institutional and commercial components of the Municipality has not been assessed. Arkin and Colton (1963) was referred for the sample size determination. Sample of 376 households were taken accordingly. Twenty representative samples each for commercial and institutional establishments were selected, and one each for special cases such as hospital, slaughter house and poultry has been assessed. Municipal household waste generation was found to be 0.093kg per capita per day which was chiefly composed of 77% organic, 18% plastic and 3% paper. Organic waste has been a major waste for institutions such as schools whereas at governmental and public offices, paper is the predominantly generated waste. Among commercial establishments, shops and restaurants mostly generate organic waste and that for departmental stores has been paper. Though collection system was found to be satisfactory, treatment and final disposal have been unsustainable. Available treatment facilities have been shut down whereas other infrastructural components have been lacking.

Arsenic contamination in water is well noted public health issue in Nepal and elsewhere. Adsorbents are important chemical means to purify the arsenic contaminated water. In this study the adsorption of As(III) on iron manganese oxide has been investigated as a function of different parameters. Herein, two iron based adsorbents, iron-manganese oxide-1 (Fe-Mn oxide-1) and iron-manganese oxide-2 (Fe-Mn oxide-2) were prepared by oxidation and co-precipitation methods. Adsorbents were characterized by powder X-ray diffraction (XRD) and scanning electron microscope (SEM). Within 4 hours of reaction time, 90% of the arsenic was removed by both Fe-Mn oxides and removal efficiency of the Fe-Mn oxide-1 was obtained higher than that of Fe-Mn oxide-2. Pseudo-second order model was well fitted to describe adsorption kinetic (R2 =0.99) for both adsorbents. Removal efficiency of the absorbents decreased with increase in the pH value and increased with increase in the concentration of adsorbent in the suspension. Based on the result, the synthesized Fe-Mn oxides have significant potential applications in the inorganic arsenic treatment in the water.