W8 PM Ecotoxicology of Agrochemicals and Pharmaceuticals
Wednesday, 16 November 2005: 1:50 PM - 5:30 PM in 337-338

(DUK-1117-466630) Field Verification of Responses of a Problematic Algal Species to Exposures of a Copper Formulation.

Duke, B¹, Rodgers, J¹, ¹ Clemson University, Clemson, SC, USA

ABSTRACT- Pond-based treatment systems (such as ash basins) can occasionally grow algae in concentrations or forms (species) that are problematic. Extensive algal growth can consume CO₂, resulting in a severely high pH (>10) and may cause elevation of total suspended solids. In order to regain control of pH and total suspended solids, the causative algal species must be controlled (loss of algae from the water column). Copper-containing algaecides are an alternative for controlling the growth of problematic algal species in these situations. It is important to understand the specific consequences of application of a copper-containing algaecide in these critical situations where National Pollutant Discharge Elimination System (NPDES) compliance must be achieved. This study was initiated at Lee Steam Station (LSS) near Pelzer, SC (Anderson County). LSS experienced high pH in their ash basin waters due to a bloom of Anabaena circinalis. Samples of ash basin water and associated algae were collected and treated in the laboratory with a series of concentrations of a copper-containing algaecide (Cutrine®-Plus). The results of this laboratory experiment indicated that 0.4-0.6 ppm Cu/L of Cutrine®--Plus should control the growth of this alga in the ash basin water at Lee Steam Station. This estimate was tested in a field study. The site water characteristics returned to background after treatment.

Key words: Anabaena circinalis, Toxicity, Copper, Algae