Effects of Wastewater Irrigation on Aqueous Geochemistry

Tedaldi, Dante J.; ,

Effects of Wastewater Irrigation on Aqueous Geochemistry

by Dante J. Tedaldi, Bechtel Environmental, Inc, San Francisco, United States,

Document Type: Proceeding Paper

Part of: Structures for Enhanced Safety and Physical Security

Abstract:

A comprehensive assessment of the environmental impact of a full-scale, operating overland flow (OLF) land treatment system was made of the Campbell Soup, Inc. OLF system in Paris, Texas. Field samples of soil, wastewater, OLF runoff, and ground water collected during the study and detailed long-term process records maintained by Campbell Soup were used as part of the evaluation. A leaky-confined aquifer of moderate salinity was found below the site. Field data and calculations indicated that the evapotranspirative concentration of salts in the applied wastewater would be insufficient to produce the measured concentrations in the ground water. A pattern of increasing ionic concentration over time (1968 to 1989) with relatively small changes in ionic ratios suggested a trend toward the dissolution and concentration of naturally present minerals (such as gypsum and sodium chloride) in the relatively slow moving ground water. The development of the slightly saline, semiconfined aquifer was strongly suggested by the ground water geochemical data, soil data, the estimated rate of infiltration, field hydraulic conductivity and water level measurements, and the magnitude of the volume of wastewater applied.

Return to search