Sydne Spinella and Jacques Smith to Present at Clemson Hydrogeology Symposium

Sydne Spinella will present “Evaluation of Different Sorption Amendments to Remove Nickel and Vanadium from Surface and Groundwater,” and Jacques Smith, PhD, will present “Evaluation of a Multi-Step Treatment Train for PFAS-Contaminated Groundwater” at the Clemson Hydrogeology Symposium at Clemson University in Clemson, South Carolina.

Sydne’s coauthors are Geosyntec’s Rachel Klinger, and SiREM’s Jacques Smith, PhD, and Rosemary Le, PhD. Jaques’s coauthors are Geosyntec’s Balaji Seshasayee, and SiREM’s Broquell Wong and Whitney Waters.

Sydne is a senior staff professional in the treatability division of SiREM. She brings expertise working in the environmental services industry, with experience in above- and below-ground community responses to warming in alpine ecosystems.

Jacques is a laboratory manager at SiREM. He has over five years of experience in environmental laboratory testing and now manages the SiREM Knoxville laboratory. His areas of expertise include next generation sequencing, coal combustion residuals (CCR) waste reclamation, leaching studies, settling and dewatering, and wastewater treatment processes.

With over 40 presentations on topics such as groundwater remediation and modeling, site characterization, geophysics, and geomechanics, the annual David S. Snipes/Clemson Hydrogeology Symposium will draw scientists and engineers from universities, government, and industry to the Madren Conference Center at Clemson University. The presentations will cover a wide assortment of topics, from hydrogeology to contaminated site remediation to geophysics.

Abstracts

Evaluation of Different Sorption Amendments to Remove Nickel and Vanadium from Surface and Groundwater

To be presented by Sydne Spinella

A site in Jacksonville, Florida, has historically recorded exceedances of surface water criteria for nickel (Ni). The Ni source has been identified as impacted groundwater that mixes with site stormwater runoff in a drainage ditch at a solid waste management unit. Geologic material in the site drainage ditch also contains impacted sediment that may contribute to exceedances. Although future remedial action includes removal of impacted sediment, there is a requirement to reduce Ni and vanadium (V) levels as soon as possible in both the groundwater and groundwater/surface water mixes. Treatment goals of 8.3 micrograms per liter (µg/L) for Ni and 50 µg/L for V were selected based on Florida’s surface and groundwater water criteria.

SiREM was tasked to evaluate multiple amendment materials that included magnesium oxide (MgO), magnesium hydroxide in the mineralized form of brucite (Mg(OH)2), pulverized concrete, biogenic apatite (Carpatite™), and chitosan flakes (ChitoVan™) for their ability to sorb Ni and V in site water. Although sorption capability was an important factor in evaluating these amendments, maintaining levels of other key dissolved metals, anions, and redox conditions were also considered. SiREM performed batch reactor tests to evaluate the five amendments.

After a five-day incubation, the data indicated that the best treatment options for both the groundwater and groundwater-surface water composite were 1% w/w ChitoVan™ or 1% w/w MgO. In the groundwater, reduction of Ni and V concentrations was observed to be as high as 10% and 99%, respectively, and when evaluated in the groundwater-surface water composite, the reduction in concentrations was similar at 11.5% and 99%, respectively.

Final analytical data of the groundwater reactors for ChitoVan™ and MgO both indicated that not only was Ni and V reduced to below the required treatment criteria, other metals of concern including aluminum (Al) and chromium (Cr) were also removed to below detection. Treatment using MgO also resulted in nondetect concentrations of dissolved iron and manganese. Both ChitoVan™ and MgO met the project treatment goals and are being considered for future field testing.

Evaluation of a Multi-Step Treatment Train for PFAS-Contaminated Groundwater

To be presented by Jacques Smith, PhD

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are a group of human-made organic compounds with a carbon backbone bonded to fluorine atoms with various functional groups at the terminal ends. Due to their useful properties such as oil and water repellence, and high thermal and chemical stability, PFAS have been used in a wide variety of industrial processes and commercial products for over six decades. These compounds are widely recognized as environmental contaminants, due to their persistence, mobility, and bio-accumulative properties.

The accepted removal of PFAS from ground- and process water typically involves filtration through granular activated carbon (GAC) or ion exchange (IX) resin. Although very effective, co-contaminants such as metals or organic carbon at certain concentrations, can limit the effectiveness of GAC and IX resins or necessitate multi-step treatments.

For a large industrial client in the Midwest, SiREM assisted Geosyntec in designing and constructing a large groundwater extraction and treatment system (GETS) to remedy PFAS impacts to groundwater. SiREM’s role was to perform bench-scale testing to evaluate chemical oxidation to remove iron (Fe), manganese (Mn), and total organic carbon (TOC) to improve PFAS removal through GAC and IX resin. Sodium permanganate in combination with a commercial coagulant was used as part of a treatment train to remove Fe, Mn, and TOC. SiREM optimized the dosage of sodium permanganate to remove the dissolved Fe to below detection and lower dissolved Mn substantially. Additional optimization using the coagulant achieved removal of the dissolved TOC to approximately 5 parts per million (ppm). In addition, the sludge generated from the pre-treatment was also analyzed for Resource Conservation and Recovery Act (RCRA) 8 metals and PFAS to evaluate solids disposal options. As a polishing step, the cleared supernatant was filtered using greensand to remove residual dissolved Mn to below detection.

More Information

About the event: David S. Snipes – Clemson Hydrogology Symposium

Event registration details: Clemson Symposium Registration

For consultation regarding presentations at this event, contact Jacques Smith at JSmith@siremlab.com