writing abstract just now ABSTRACT Arsenic contamination of groundwater is a major concern on a global scale. It is the most challenging health hazard in Bengal delta plain including Bangladesh, India and Nepal. Arsenic is present in groundwater mainly in inorganic forms, arsenate,H2AsO4- [As(V)] and Arsenite, H3AsO3[As(III)]. Arsenic is assumed to desorb from the surface of Fe(OH)3 when the reducing environment exists in the aquifer. The objective of this study is to emphasize the application of mass transport equation to simulate transport processes of arsenic and other background species by coupling with groundwater flow equation and conceptual model assumed above. The case studies of chemical analysis of arsenic in spring water was carried out to know the behavior of arsenic species to test the validity of conceptual model. Arsenic detection technique by using Hironaka’s Kit was employed for the chemical analysis. Arsenic is liberated as arsine, AsH3, by NaBH4 and Vitamin-C in a Test tube type Gutzeit generator. The generated arsine is passed through 10 mm I.D.-disk test paper. The generated arsine produces a yellow-brown stain on test paper impregnated with mercuric bromide or silver nitrate. The developed color of the stain is roughly proportional to the amount of arsenic (III) present.