It Is Very Well Known That There Is Acute Shortage of Good Quality Drinking Water. the Quality of Water Which the Common Man Drinks Is Not at Par With the Indian Standard Specifications For Drinking Water I.E., Is-10500. the Mine Water Coming Out from Jharia Coal Fields, Raniganj Coal Field, Central Coal Field, Talcher Coalfield, Northern Coalfield, North Eastern Coal Field and Western Coalfield,When Characterized Revealed That In Most of the Cases, Higher Values of Tss, Tds, Fe, Mn, Cl, F, So4, Cu, As, Hg, Cn, Ni, Cr, Al, Zn, Nitrate, Hardness, Phenol, Oil Grease and Coliform Were Observed As Compared to the Respective Values Givenin Is-10500. When This Water Were Treated With Optimum Dose (Concentration and Time) of Ozone, the Results Were Encouraging and the Higher Values of the Above Parameters Were Reduced and Found to Be at Par With Is -10500. Since This Work Was Carried Out For a Private Party on Payment Basis, the Details of the Data Generated at Different Doses of Ozone (Concentration and Time) Cannot Be Provided. the Present Paper Deals With the Basic Principlesscience Behind Such a Reduction I.E., Conversion of Mine Water to Potable Water.