Evaporation Pond Groundwater Control

Trihydro provided hydrogeologic and engineering services to address groundwater impacts at a mine and mineral processing site in Wyoming. The high total dissolved solids (TDS) wastewater produced during processing was disposed of in large evaporation ponds located along a nearby drainage. Leakage from these ponds resulted in groundwater impacts. Trihydro assessed the extent and migration pathways of high TDS groundwater plumes at the site, developed defensible calculations of salt loading to an adjacent river, and designed and implemented engineering improvements to two groundwater capture systems to enhance their effectiveness and reliability.  

The geologic and hydrogeologic environment was investigated near operating evaporation ponds used by the facility to manage high TDS groundwater. Trihydro developed a conceptual site model (CSM) for the leakage and migration of high TDS groundwater water and conducted plume mapping to define the downgradient extent of high TDS groundwater. This work demonstrated that the shallow plume downgradient of the facility’s evaporation ponds in one drainage did not extend to the river.  

Trihydro also supported a re-evaluation of the sitewide groundwater monitoring network to eliminate monitoring wells that may be resulting in the collection of misleading or erroneous groundwater data. In addition, Trihydro guided a revision in the groundwater monitoring program that reduced costs through the use of an inexpensive field parameter measurement in place of collecting groundwater samples for laboratory analysis.