In soil and sludge soil is acid. Arsenic is caught with iron oxide, but is spotted to catch with limestone and neutral conditions to match with clay-minerals.
In soil and sediment that is acidic. Arsenic binds to the iron oxide But in an alkaline condition to grips with limestone. And in neutral to grips with. clay-minerals
In soil and sediment with acidity. Arsenic will catch up with iron oxide. But in alkaline will catch up with limestone. Under the condition of neutral and will catch up with clay-minerals.