igr ams ▁per ▁liter ▁just ▁up stream ▁of ▁Lewis burg , ▁ 4 2 . 1 ▁mill igr ams ▁per ▁liter ▁in ▁Lewis burg , ▁and ▁ 4 1 . 8 ▁mill igr ams ▁per ▁liter ▁near ▁the ▁mouth . ▁The ▁concentration ▁on ▁the ▁stream ' s ▁trib ut aries ▁r anged ▁from ▁ 2 9 . 3 ▁to ▁ 3 6 . 2 ▁mill igr ams ▁per ▁liter . ▁ ▁The ▁concentration ▁of ▁sod ium ▁in ▁Lim estone ▁Run ▁ranges ▁from ▁ 3 . 4 7 ▁mill igr ams ▁per ▁liter ▁near ▁the ▁source ▁to ▁ 7 . 9 3 ▁mill igr ams ▁per ▁liter ▁near ▁the ▁mouth . ▁The ▁mag nes ium ▁concentration ▁ranges ▁from ▁ 1 9 . 2 ▁mill igr ams ▁per ▁liter ▁near ▁the ▁stream ' s ▁source ▁to ▁ 2 6 . 5 ▁mill igr ams ▁per ▁liter ▁in ▁the ▁middle ▁reaches ▁of ▁the ▁stream . ▁The ▁minimum ▁concentration ▁of ▁al umin um ▁is ▁ 8 ▁mill igr ams ▁per ▁liter ▁up stream ▁of ▁Lewis burg ▁and ▁the ▁maximum ▁concentration ▁is ▁ 1 5 ▁mill igr ams ▁per ▁liter ▁near ▁the ▁source . ▁The ▁pot ass ium ▁concentration ▁ranges ▁from ▁ 1 . 4 3 ▁mill igr ams ▁per ▁liter ▁up stream ▁of ▁Lewis burg ▁to ▁ 2 . 5 ▁mill igr ams ▁per ▁liter ▁near ▁the ▁source . ▁The ▁concentration ▁of ▁calci um ▁in ▁the ▁stream ' s ▁waters ▁ranges ▁from ▁ 4 8 . 4 0 ▁to ▁ 6 9 . 9 0 ▁mill igr