What percentage of us water sources are considered to be polluted?

As published in EPA's national water quality inventory report,
 
40 Percent of rivers and 46 % of lake are considered to be plluted. these sources, called the surface water are vulnerable to pollution discharged of pipesand runof pollutants washing off the lands.

These sources are extremely unsafe to drink and to swim in

Magma forms by partial melting of upper mantle and crust. partial melt means that only a fraction of the available material forms a melt, and that the remainder stays solid. the partial melt rises because of its lower density and ascends through he crust. this is so conclusive mean the answer would be magma igneous rocks or balistic magma.