Tag: Matt Polizzotto

Evaluating Sources of Zinc Contamination within Eugene-Springfield Waterways

Presenter: Charlotte Klein − Environmental Science, Spatial Data Science and Technology

Faculty Mentor(s): Matt Polizzotto

Session: (In-Person) Poster Presentation

Stormwater runoff occurs when rainfall encounters impervious surfaces such as pavement and rooftops, instead of being absorbed into the ground. As runoff travels over these surfaces, pollutants are picked up and eventually make their way into natural waterways. In the Eugene-Springfield metro area, a specific stormwater pollutant of concern is zinc, which has been notably rising in local ambient water quality measurements taken by the city of Eugene over the past 20 years. As such, the causes and extent of elevated zinc levels within waterways in the Eugene-Springfield metro area are the focus of this study. Using 2019 as a case study year, data aggregation revealed similar zinc concentration patterns within the waterways of Springfield and Eugene. Literature review and spatial analysis identified zinc-based moss control products, tire and brake wear, and industrial discharges, as likely sources of zinc to the environment. This work adds to the understanding of municipal stormwater pollution in the Pacific Northwest and can lead to informed strategies for minimizing zinc loading to the environment.

Arsenic and Fluoride Contamination Analysis of Agricultural Topsoil in Guanajuato, Mexico

Presenter(s): Katie Fischer

Faculty Mentor(s): Matt Polizzotto

Poster 33

Session: Sciences

Groundwater from Guanajuato, Mexico’s Independence Basin has recently been documented to contain elevated levels of arsenic (As) and fluoride (F) from past volcanic activity within the region. Guanajuato’s groundwater poses a potential health risk to residents that utilize the groundwater as drinking water, resulting in chronic exposure to toxic levels of As and F. Although contaminated groundwater is extensively used for irrigation, it remains unclear as to whether contaminants are accumulating in agricultural soils and threatening the quality of crops. Therefore, the primary objective of this work was to understand the scale of contaminant accumulation within the region’s topsoil. To do this, we analyzed fifteen batch soil samples from four farms within Guanajuato using inductively coupled plasma mass spectrometry (ICP-MS) for initial levels of arsenic in topsoil, then analyzed sixteen soil core samples from three farms using a fluoride ion selective electrode to form depth profiles for F accumulation within topsoil. We found that As in agricultural topsoil is currently below the EPA standard of 0.39 parts per million (ppm) for arsenic contamination in soils, ranging from 0.018 ppm to 0.059 ppm. Ongoing work is seeking to define the loading limits of As and F, which influences how much As and F the soil can retain. Ultimately, understanding how As and F accumulate within the region’s agricultural topsoil contributes towards creating a management plan in regards to how much and for how long local farmers can irrigate with contaminated groundwater before As and F levels in topsoil become potentially hazardous.