Why do I need a 3.04 General Permit: Non-Stormwater Impoundments at Mining Sites?

This permit is for discharges to lined surface impoundments, lined secondary containment structures, and associated lined conveyance systems at mining sites. Activities that prompt the need for this permit are: seepage from tailing impoundments, unleached rock piles, or process areas; process solution temporarily stored for short periods of time due to process upsets or rainfall; stormwater runoff not permitted under A.R.S. § 49- 245.01 because the facility does not receive solely stormwater or because the runoff is regulated but not considered stormwater under the Clean Water Act; wash water specific to sand and gravel operations not covered1 . This permit is valid for five years.