Survey of Galveston Bay bottom sediments and benthic communities

The purpose of this study was to characterize the quality of sediments at key sites in the Galveston Bay Estuary (Table 1, Fig. 1). Synoptically collected sediment samples were taken for chemical and physical analyses, toxicity testing, and an assessment of benthic community structure in order to identify areas where sediment contamination is responsible for ecosystem degradation (Chapman, 1990). The chemical analyses included a suite of trace metals, petroleum aromatic hydrocarbons (PAHs), chlorinated hydrocarbons, total organic carbon (TOC), and acid volatile sulfides (AVS), in order to normalize the organic and inorganic constituents, respectively. Solid-phase sediment toxicity tests with the benthic amphipod Grandidierella japonica were conducted (ASTM, 1990). In addition, the U.S. Fish and Wildlife Service (USFWS) conducted a series of sediment porewater tests with gametes of the sea urchin, Arbacia puntulata (Carr and Chapman, 1992).