Water and streambed-sediment samples were collected on March 9 and 10, 1987 from one site upstream and three sites downstream of the discharge from a municipal wastewater-treatment plant on Rowlett Creek. Purge-and-trap, closed-loop stripping, and ph-adjusted solvent extraction methods for water samples, and a Soxhlet-solvent extraction method for streambed sediment were used with gas chromatography/mass spectrometry for separation and identification of organic compounds. Results of the analyses confirm the persistence of many organic compounds in water as far as 13.5 kilometers down- stream from the wastewater-discharge point. These compounds include: (1) the volatile organic com- pounds chloroform, 1,2-dichlorobenzene, 1,4-dichlorobenzene, tetrachloroethene, and trichlo- roethene; (2) several linear alkylbenzene compounds, octyl phenol, and a tetramethylbutyl phenol isomer that are related to detergent use; (3) 9-phenyl- 9H-carbazole, a compound related to cal tars and coal compustion residues; and (4) caffeine. The only compound detected in water in concentrations greater than U.S. Environmental Protection Agency's maximum contamination levels for drinking water was tetra- chloroethene (6.0 micrograms per liter) in a sample collected 13.5 kilometers downstream from the dis- charge point. Compounds identified in the streambed- sediment samples include a xylene isomer at 7.7 kilometers and chrysene, fluoranthene, pyrene, and a xylene isomer at 13.5 kilometers downstream from the wastewater discharge.
Additional publication details
USGS Numbered Series
Organic compounds downstream from a treated-wastewater discharge near Dallas, Texas, March 1987
Water-Resources Investigations Report
U.S. Geological Survey ;
USGS ESIC, Open-File Reports Section [distributor],