ity ▁units , ▁ranges ▁from ▁ 4 . 2 ▁in ▁the ▁upper ▁reaches ▁of ▁Lim estone ▁Run ▁and ▁ 6 . 2 ▁on ▁a ▁trib ut ary ▁in ▁the ▁middle ▁reaches ▁of ▁the ▁waters hed ▁to ▁ 1 2 . 6 ▁in ▁Lewis burg ▁to ▁ 2 5 . 3 ▁in ▁the ▁middle ▁reaches ▁of ▁Lim estone ▁Run . ▁ ▁The ▁concentration ▁of ▁total ▁dissol ved ▁sol ids ▁in ▁the ▁waters hed ▁of ▁Lim estone ▁Run ▁is ▁approximately ▁ 0 . 2 8 9 ▁to ▁ 0 . 2 9 ▁mill igr ams ▁per ▁liter ▁near ▁its ▁head w aters . ▁In ▁the ▁middle ▁reaches ▁of ▁the ▁stream , ▁the ▁total ▁dissol ved ▁solid ▁concentration ▁is ▁approximately ▁ 0 . 3 8 ▁to ▁ 0 . 3 8 8 ▁mill igr ams ▁per ▁liter . ▁S light ly ▁up stream ▁of ▁Lewis burg , ▁the ▁concentration ▁is ▁about ▁ 0 . 3 7 ▁or ▁ 0 . 3 8 ▁mill igr ams ▁per ▁liter . ▁The ▁concentration ▁of ▁total ▁dissol ved ▁sol ids ▁in ▁Lewis burg ▁is ▁also ▁ 0 . 3 7 ▁or ▁ 0 . 3 8 ▁mill igr ams ▁per ▁liter . ▁Near ▁the ▁mouth , ▁the ▁concentration ▁is ▁ 0 . 3 6 4 ▁mill igr ams ▁per ▁liter . ▁The ▁total ▁dissol ved ▁sol ids ▁concentration ▁on ▁Lim estone ▁Run ' s ▁trib ut aries ▁ranges ▁from ▁ 0 . 2 6 2 ▁to ▁ 0 . 3 7 8 ▁mill igr ams ▁per ▁liter . ▁ ▁The