MAY 2023 LUNCHEON MEETING
Mindy Faulkner
presents
Geochemical Characterization of Base Metals in Stream Water and Sediments in the Caddo Lake Watershed, Cass, Harrison and Marion Counties, Texas
11:30 AM Wednesday, May 17, 2023
at Hollytree Country Club
6700 Hollytree Dr
Tyler, TX 75703
Cost: $25
Abstract
Authors: Mindy Faulkner, Melanie L. Ertons, Joseph W. Watkins
The Caddo Lake watershed is located in northeastern Texas and encompasses much of Cass, Harrison, and Marion counties. The watershed is drained by major streams and tributaries flowing in an easterly direction over Eocene-aged rocks and sediments of the Wilcox and Claiborne groups, and empty into the western arm of Caddo Lake. Since 1995, Caddo Lake and some of its tributaries have been included on the State of Texas Clean Water Act 303(d) list by the Texas Commission on Environmental Quality (TCEQ) for impairment due to mercury content in edible tissue, depressed dissolved oxygen, base metal concentrations, and low pH values. The purpose of this multi-year study was to characterize base metal concentrations in stream water and sediments in the Caddo Lake watershed, and document the potential watershed transport and contribution to the impairment of Caddo Lake. Recent water (n = 58) and sediment (n = 116) sampling at 29 sites revealed copper, lead, and zinc concentrations within normal limits and below EPA actionable standards. Mercury concentrations were elevated at 21 of the 29 sampling sites, which could lead to methylation and bioavailability to organisms at all trophic levels.
Biography
Dr. Mindy Faulkner joined SFASU in 2005 after completing her B.S. and M.S. in Environmental Geology from Stephen F. Austin State University. In 2016, she completed her Ph.D. in Forestry from the Arthur Temple College of Forestry at SFA and was recently promoted to Associate Professor in the Department of Earth Sciences and Geologic Resources. Dr. Faulkner’s primary research interests include the geologic controls on the spatial distribution of natural resources in the earth’s crust, integrating the study of geoscience, hydrogeology, geochemistry, and ecological systems. Current research by Dr. Faulkner has focused on the various ways to characterize geologic and geochemical phenomena using a complement of field methods, instrumentation, and remote sensing techniques. Recent work by Dr. Faulkner has been in concert with graduate students in karst terrains of Central Texas, bauxite residues in Central Arkansas, the Martin Lake Ash Disposal Area near Tatum, and the Caddo Lake watershed.