These titles and more can be found in the Reference Collection on the first floor of Foley Library.
Encyclopedia of Earth Science - REF QE5.K85 2005
Encyclopedia of Environmental Pollution and Cleanup - REF TD173.E53 1999
Environmental Crime: A Sourcebook - REF HV6403.B87 2004
Environmental Encyclopedia - REF GE10.E38 2003
Encyclopedia of Global Change - REF GE149.E445 2002
Environmental Guidebook: A Selective Reference Guide to Environmental Organizations and Entities - REF TD171.S76 2002
Handbook of Environmental Data on Organic Chemicals - REF TD196.O73 V47 2001
New Atlas of Planet Management - REF HC79.E5N46 2005
Water Encyclopedia - REF TD345.W26 2005
World Atlas of Biodiversity: Earth's Living Resources in the 21st Century - REF QH541.15.B56 G76 2002
Not sure which encyclopedia or dictionary will have coverage of your topic? Search Reference Universe, a cumulative index to electronic and print reference works at Foley Center Library.