09-14-2021

Arsenic Mobilization From Glacial Sediment Into Groundwater

Technical Webinar

A Technical Webinar Series

Background/Objectives

Monitored natural attenuation of petroleum hydrocarbons has become the remedy of choice
in the United States and internationally. This approach requires evidence of effective
retardation processes to address public and regulatory concerns. Less well-understood are
the secondary effects of these processes. Of particular concern is the release of trace metals
and arsenic from sediment into groundwater in aquifers affected by petroleum releases.

Approach/Activities

Working at an intensively studied site near Bemidji, Minnesota, United States Geological
Survey (USGS) scientists and collaborators focused on the question of whether naturally
occurring arsenic in the glacial aquifers might be mobilized in the presence of hydrocarbon
because of chemical interactions involving iron hydroxides, which also occur naturally. To
address this question, arsenic concentrations were measured and reactions modeled for
several years in groundwater and in sediment from the hydrocarbon plume at Bemidji.

Results/Lessons Learned

In this long-term field study, we found that changes in geochemistry from the natural
breakdown of petroleum hydrocarbons underground can promote the chemical release
(mobilization) of naturally occurring arsenic into groundwater. This geochemical outcome
can result in potentially significant arsenic groundwater contamination, predicted to last
for centuries.

About The Presenter

Isabelle Cozzarelli, PhD — Dr. Isabelle Cozzarelli received her PhD from the University of Virginia in 1993. As a geochemist in the USGS Water Mission Area, she conducts longterm interdisciplinary research on the environmental fate and effect of organic contaminants, such as fuels and fuel waste products. She has more than 100 published research papers. Throughout her career she has committed herself to mentoring students and junior scientists in the field and in her laboratory in Reston Virginia. She currently serves as Team Leader of the USGS Toxics Program project on Fate and Effects of Wastes from Unconventional Oil and Gas Development. Dr. Cozzarelli has an adjunct faculty position at Virginia Tech. In 2005, she was elected GSA Fellow by the Geological Society of America.

This webinar will take place on September 29th at 12:30 PM EST.
Join on your computer or mobile app: Click here to join the meeting.
Or call in (audio only): +1 951.465.7634
Phone Conference ID: 668 054 796#

Back to top
facebook-pixel linkedin-pixel linkedin pixel focused image