Abstract
The “spotlight” column draws attention to selected articles in Environmental Engineering Science (EES), the official journal of the Association of Environmental Engineering and Science Professors (AEESP). Spotlight articles appear regularly in the journal as an Editor's Note, as well as in the AEESP newsletter. Through publication of high-quality peer-reviewed research, the EES journal helps AEESP achieve its mission of developing and disseminating knowledge in environmental engineering and science. In this entry, we shine the spotlight on selected articles from the April 2019 issue through the July 2019 issue of EES. Congratulations to all whose work is highlighted.
Fluorine is the most widespread contaminant in surface water and groundwater in western United States, Mexico, Argentina and several countries in Asia and Africa. Adsorption is one of the cost-effective water treatment methods for removing fluoride. However, there remains a need to identify and develop a new generation of more cost-effective adsorbents for removing fluoride. A study by Wallace et al. (2019) demonstrated the efficacy of 11 (hydro)oxide nanomaterials for removing fluoride from water using both batch and fixed bed continuous flow through column systems. These nanomaterials include hematite, magnetite, ferrihydrite, goethite, hematite-alpha, hydroxyapatite (HAP), brucite, and four different titanium dioxides. Among the 11 nanomaterials, ferrihydrite, HAP, and brucite were found to demonstrate potential for remediating fluoride-polluted water. The authors indicated the need for pilot scale studies to assess the performance of the three nanomaterials for large-scale applications, especially for treating fluoride in complex industrial wastewaters. They also highlighted the need to evaluate the regeneration and reuse capacity of these three nanomaterials.
Hydraulic fracturing uses a range of chemicals (i.e., “fracturing fluids”) to break open impermeable pores and release the previously inaccessible oil and natural gas in shale formations. This technology generates voluminous amounts of oil and gas wastewater that is characterized by unusual high levels of total dissolved solids and a range of toxic and radioactive chemicals. Improper disposal or the accidental release of the fracturing fluids from oil and gas wastewater threatens ecological health of the subsurface environment. Thus, it is important to understand the biodegradation patterns of the fracturing fluids in soil environments. Lozano et al. (2019) studied the ability of six representative fracturing fluids to enrich indigenous microbial communities in a typical surface soil for nearly 78 days. As expected, the chemical oxygen demand exerted by all the fluids decreased over time; however, a significant recalcitrant fraction was observed for four of the six amended fluids. Their Illumina MiSeq sequencing of a 16S ribosomal RNA gene amplification and polymerase chain reaction studies revealed that 24 bacterial taxa were closely related to known species, specifically to well-known xenobiotic degraders. The composition of the enrichment was unique for each of the six fluids. Their study implied that the composition of fracturing fluids exerts a critical influence over the design of bioremediation efforts.
Harmful algal blooms in Utah Lake have been reported to be influenced by both the internal and external sources of nutrients (nitrogen and phosphorus). The shallow nature of Utah Lake renders it vulnerable to rapid evaporation and sediment disturbance during windstorms and summer seasons, resulting in internal nutrient release from sediments. Externally, the lake receives continuous treated discharges from seven wastewater treatment plants. Hogsett et al. (2019) studied the impacts of internal phosphorus loading on eutrophication of the Utah Lake. Their study was focused on understanding the internal nutrient recycling and its triggering factors by determining three major factors, namely the oxygen demand associated with the water column and sediment, nutrient fluxes under ambient conditions and changing dissolved oxygen and pH scenarios, and sediment characteristics and their effects on sediment oxygen demand and nutrient flux. Their study highlighted the importance of implementing nutrient reduction strategies that are capable of decreasing sediment nutrient content, nutrient flux, and water column phytoplankton biomass.
As the world population is approaching 8 billion, there is an ever-increasing need to develop conscious stewardship of the three vital resources, food, energy, and water (FEW). Considering the critical need to secure future for the next generation, it is important to recognize that water security, energy security, and food security are closely linked with one another. Simply put, the negative actions in one particular area often can significantly degrade one or both of the other areas. The past decade has witnessed the evolution of FEW nexus as a separate field of study, especially to understand intricate dependencies among these three resources. The introductory article (Grady et al., 2019) in a special issue of EES provides an excellent overview of how environmental engineering and science interdisciplinary efforts play a critical role in understanding and protecting food security, water resources, and sustainable energy. The entire issue focuses on new methodological approaches for FEW modeling, theoretical dialogue, and ways to transition theory into practice.