Usable water means an aquifer or its portion that:
(i) Supplies any public water system; or
(ii) Contains a sufficient quantity of ground water to supply a public water system and either:
(A) Currently supplies drinking water for human consumption; or
(B) Contains fewer than 10,000 mg/l total dissolved solids; and
(2) Is not an exempted aquifer under state law.
36 CFR § 9.40
In addition to the definitions in 36 CFR 1.4, the following definitions apply to this subpart: