NUTRIENT AND SURFACTANT ENHANCEMENT FOR THE BIODEGRADATION OF CHLORINATED HYDROCARBONS IN THE WASTE-WATER FROM A LOUISIANA SUPERFUND SITE

Surfactant based soil washing and flushing is an emerging technology f or Superfund site remediation in the United States. The presence of su rfactants in the wastewater, however, poses challenging problems for s ubsequent biological or physical-chemical processes. The objective of this research is to evaluate the potential effects of selected surfact ants on the biodegradation of chlorinated hydrocarbons in the wastewat er from the Petro Processors (PPI) Superfund site north of Baron Rouge , LA. Results from this study showed that biodegradation of a real wor ld waste containing a broad array of hazardous contaminants was signif icantly enhanced by the amendment of mineral nutrients and surfactants , especially a nonionic surfactant Witconol. The enhancement based on TOC reduction was 49% higher for the mixture of PPI wastewater with Wi tconol than the combined biodegradation of PPI wastewater and Witconol alone, whereas a similar enhancement was observed with an anionic sur factant sodium dodecylsulfate (SDS). The addition of mineral nutrients was also shown to further enhance the biodegradation of PPI wastewate r, with a 13% increase in TOC reduction as compared to the nutrient li mited controls. Nutrient addition significantly increased microbial gr owth, biodegradation, and foam degradation of surfactant-laden PPI was tewater. (C) 1998 Elsevier Science B.V. All rights reserved.