The first U.S./U.S.S.R. Joint Conference on Environmental Hydrology and Hydrogeology was held in Leningrad, U.S.S.R., June 18–21, 1990. The conference was a significant event in the hydrological sciences because it opened communications between the Soviet and American scientific communities.

The meeting brought together 188 American and 200 Soviet scientists, engineers, government officials and policymakers, who exchanged information and discussed major issues in hydrology and hydrogeology. Topics included emerging issues in hydrology and hydrogeology, the human impact on the global hydroenvironment, regional and global groundwater issues, flow and transport modeling, groundwater protection and monitoring, hazardous and radioactive waste disposal, rural and urban contamination, and techniques of investigation and remediation.