Synthetic Water Development

Photo Credit: Tristan Weir

Prior to testing any alternative methods of water treatment, a source of water was identified. Actual well water could not be obtained from any of the Bennett Freeze Area (BFA) wells due to difficulty in securing permits and Navajo Nation Chapter House Resolutions for the sampling and removal of water from the Navajo Nation. For this reason, synthetic water was developed.  Water chemistry of three BFA wells was used for the purposes of designing a synthetic water for this project. The synthetic water goals are a pH of 7.8-8.4, a uranium concentration of 100 µg/L, an arsenic concentration of 70 µg/L. Additionally, a coliform count of less than 100 CFU/100mL is desired. Since the BFA water is groundwater, the synthetic water should ideally be sourced from a groundwater well to best attempt to model the water chemistry.

Creating the synthetic water involves several steps. These steps include:

1. Acquisition of a local water source containing coliforms
2. The acquisition of a local groundwater source with more characteristic water chemistry to better model the BFA groundwater
3. The determination of the ratio of groundwater to coliform-containing water
4. The creation of standard uranium and arsenic solutions from purchased stock solutions
6. Spiking of the locally sourced water with the uranium and arsenic standards

The results of the synthetic water creation are compared to the desired synthetic water goals in the table below. The uranium concentration in the synthetic water is less than desired, and may be due to human error in spiking the groundwater/surface water blend.

Project Details

• Design Constraints and Requirements
• Design Alternatives
• Synthetic Water Development
• Column Testing of Alternatives
• Modular Configuration Testing
• Final Design Recommendations
• Design Drawing