Description: We are rehabilitating an existing lifeless pond fed by an old mine drain, the primary source of water during dry weather. The acid mine drainage in this area has pH 3.3 and is contaminated with aluminum (Al). We installed a passive treatment system for the mine drainage, which restored the pond. An Eagle Scout project funded in part in 2011 by the FPW, installed flow measurement structures. The data collected resulted in a treatment system plan that involved a passive drainable limestone bed, containing 450 tons of limestone aggregate in a bed that is 4 ft deep. The AMD flows through the limestone and discharges to the existing pond. The bed is drained weekly into a settling basin to maintain its permeability. In order to minimize the footprint of the treatment system and thus lessen impact to the Woodland Garden, the drainable limestone bed was built within a concrete tank. The entire project is carefully ensconced in the Woodlands Garden, a very public area of the Botanic Garden. It is aesthetically integrated into the landscape. The top of the limestone bed is developed as a walking path with a boardwalk on top - the scene of yoga classes. The system is designed to facilitate maintenance that has not yet been necessary but is expected in a couple years. The impact of the overall Pittsburgh Botanic Garden’s Woodlands AMD Passive Treatment System includes the restoration of a pond and the stream below the pond. The pond is planted with aquatic plants and stocked with fish. The project is one of the centerpieces of the Woodlands Gardens and was viewed by at least 15,000 people as of December 2015. The system removes 2.5 lbs. of aluminum per day, 76 lbs. per month and 912 lbs. per year as it treats 11,520 gallons of the polluted water each day, 4.2 million gallons per year. The pH has improved from 2.9 to 7.1. The system adds 21.9 lbs. per day or 4 tons per year of alkalinity (as calcium carbonate) to the water which helps to neutralize other acidic inputs in the watershed.