Event Title

Determining Lead Speciation and Mobility in Soil from an American Civil War Battlefield by Potentiometric Stripping Analysis

Mentor 1

Joseph Aldstadt

Location

Union Wisconsin Room

Start Date

29-4-2016 1:30 PM

End Date

29-4-2016 3:30 PM

Description

The Manassas National Battlefield was the site of a climactic battle during the American Civil War. The area has been apparently undisturbed by agricultural practices and other potential contaminants since 1862, thereby making it an ideal place to examine long-term pollutant movement in a soil matrix. Lead from bullets dropped along the infantry firing lines is readily measured in the soil, and its migration in the sub-surface can be evaluated. A standard Sequential Extraction method was used to separate the different lead compounds present in the soil. A method based upon Potentiometric Stripping Analysis (PSA) with a mercury film electrode was developed and optimized to determine the concentration of lead present in various environmental "compartments". In this method a potential is applied to a sample cell causing the Pb2+ ions to be reduced onto the mercury film surface. The potential is then turned off allowing the accumulated lead to be oxidized from the working electrode back into solution. The resulting response is a plot of the change in potential measured versus time. Results using the PSA method will be compared to Atomic Absorption Spectroscopy (AAS) data. Knowing the species of lead present within a soil matrix can help researchers understand how much of the total lead present is bioavailable. This information can also help to establish more accurate estimates of the rate of transport in the sub-surface. Having a robust method for lead speciation at trace levels in soil can help to more accurately identify areas of concern for remediation as well.

This document is currently not available here.

Share

COinS
 
Apr 29th, 1:30 PM Apr 29th, 3:30 PM

Determining Lead Speciation and Mobility in Soil from an American Civil War Battlefield by Potentiometric Stripping Analysis

Union Wisconsin Room

The Manassas National Battlefield was the site of a climactic battle during the American Civil War. The area has been apparently undisturbed by agricultural practices and other potential contaminants since 1862, thereby making it an ideal place to examine long-term pollutant movement in a soil matrix. Lead from bullets dropped along the infantry firing lines is readily measured in the soil, and its migration in the sub-surface can be evaluated. A standard Sequential Extraction method was used to separate the different lead compounds present in the soil. A method based upon Potentiometric Stripping Analysis (PSA) with a mercury film electrode was developed and optimized to determine the concentration of lead present in various environmental "compartments". In this method a potential is applied to a sample cell causing the Pb2+ ions to be reduced onto the mercury film surface. The potential is then turned off allowing the accumulated lead to be oxidized from the working electrode back into solution. The resulting response is a plot of the change in potential measured versus time. Results using the PSA method will be compared to Atomic Absorption Spectroscopy (AAS) data. Knowing the species of lead present within a soil matrix can help researchers understand how much of the total lead present is bioavailable. This information can also help to establish more accurate estimates of the rate of transport in the sub-surface. Having a robust method for lead speciation at trace levels in soil can help to more accurately identify areas of concern for remediation as well.