In response to a request from Baltimore District, five members of the Committee on Water-Quality met with NAB personnel on 14-15 June 1983 to assist the District in evaluation of water quality problems at the Tioga - Hammond Lakes project. The Tioga - Hammond Lakes project is located in northeastern Pennsylvania. The project consists of two lakes, Tioga Lake on the Tioga River and Hammond Lake on Crooked Creek, which are connected by means of a channel with a control structure. Runoff from the Crooked Creek watershed above Hammond Lake is of good quality and is mildly alkaline in nature. Runoff from the Tioga River watershed above Tioga Lake is adversely impacted at times by acid mine drainage. This acid inflow is believed to have been the cause of minor fish kills in Tioga Lake, following ice formation, during each winter season since the project was completed. The groups initial efforts to evaluate the causes of the fish kills included a review of the existing water quality data base. It was determined that insufficient data were available to firmly establish causes of the problem or make recommendations for specific solutions. The remaining discussion then was devoted to general causes and effects, evaluation of data and study needs, as well as possible remedial measures after additional information was developed.