EM-MM- Percentage of mine sites where acid rock drainage is: 1) predicted to occur, 2) actively mitigated, and 3) under treatment or remediation 1) One of ten actively managed sites (10%) (Greens Creek Mine) has long-term potential for acid generation (decades into the future) and these materials are being actively managed through selective handling and ultimate placement within lined containment with covers to minimize and control any potential seepage.