Scott Alexander with Malcolm Crittenden and Robert Ryder, PA Department of Environmental Protection (DEP), “Instream Limestone Sand Dosing in the Allegheny Plateau” Attendees will learn of the successful recovery of trout populations in low-buffered, acidic streams by the use of alkaline treatments. Documented low-cost/long term trout restoration methods such as (ILS) may be useful for other watersheds dealing with stream acidification because several high cost alternatives have been proposed in Pennsylvania which on analysis may deliver far less stream-alkalinity per dollar.