Solving Groundwater Contamination: Another Piece of the Puzzle

Posted by on Apr 25, 2018 in Blog | 0 comments

In explaining how you go about solving complex soil and groundwater problems, we’ve used various analogies over the years, including putting together pieces of a jigsaw puzzle and assembling building blocks to develop a robust conceptual site model.

The point being, soil and groundwater assessment and remediation can be complex, and in order to find the best solution, you will often need more than one tool and/or one discipline to get you to your end point.

Dr. Fatemeh Vakili, who joined Dragun in December 2017, talked about one of the available tools at the recent Battelle Chlorinated and Recalcitrant Compounds Conference in Palm Springs, CA.

Poster Presentation

Dr. Fatemeh Vakili explaining her research to an attendee at a recent conference.

Factors that May Affect the Transport of Chlorinated Ethenes in Groundwater

Below is a short Question and Answer session with Fatemeh:

Q:  What was the title of your presentation?

A:  Chlorine and Hydrogen Isotope Fractionations in Chlorinated Ethenes during Physical Processes

Q:  What is the practical application of your work?

A:  My work can help to identify whether physical processes (such as sorption, diffusion, and back diffusion) affect the transport of chlorinated ethenes, such as TCE, in the subsurface.  The sorption process slows the transport of solvent contaminants in groundwater and is one of the key elements in consideration of natural attenuation.  Back diffusion of the previously-diffused contaminants from low permeability materials, such as clay layers or bedrock, is a slow process and can act as a secondary source of contamination for decades.  Therefore, the back diffusion process needs to be considered when evaluating remedial approaches.

Q:  Where do you think your expertise will be most helpful (types of contamination or challenges)?

A:  At sites where low concentrations of chlorinated solvents exist and monitored natural attenuation is considered as a remedial option.  Also at those sites where there is a possibility of back diffusion from impacted low permeability zones.

Q:  What were some of the questions that were asked of you during the poster presentation?

A:  Could you explain your experiments?  Have you calculated fractionation factors for your experiments?  Did you investigate the effect of biodegradation on hydrogen isotope fractionation?

Q:  Anything else you would like to add?

A:  I would like to thank Isotope Tracer Technologies, Inc. (IT2) for the opportunity to analyze my samples at their lab and Dragun Corporation for the support to present my work at Battelle Chlorinated 2018.

Fatemeh is working closely with our senior staff (Dr. Michael Sklash, in particular) and learning the practical application of her educational training at the University of Waterloo.  She is also gaining valuable field experience as she learns firsthand the “nuts and bolts” of site investigation and remediation.

Whether jigsaw pieces or building blocks, Fatemeh’s expertise will most certainly be useful as we continue to focus on solving complex soil and groundwater issues.

If you have questions for Fatemeh, feel free to contact her directly at 519-979-7300, Ext. 123.  If you have questions about assessment/remediation or litigation support on a groundwater issue, contact Michael Sklash, Ph.D., P. Eng., at 519-979-7300, Ext. 120.