The maximum contaminant level (mcl) set by the epa of thallium in drinking water is 0.0020 mg/l . convert the mcl of thallium from milligrams per liter to parts per billion (ppb). converted mcl of thallium: ppb a farmer recently dug a new well for his property. he sends a 16.0 ml sample of the well water to the epa to be tested for the presence of thallium. what is the maximum amount of tl (in μg ) that can be present in this 16.0 ml sample based on its mcl? maximum amount of tl : μg suppose the farmer rethinks his plan and digs a new well on the other side of his property. he sends in a new 16.0 ml sample. after testing, the epa determines that the sample of water contains 0.00164 μg/ml tl . is the thallium level of the new well water safe to consume? yes not enough information no