The Velsicol Chemical Plant, the source of extreme environmental contamination in the Michigan rural community of St. Louis, has been gone for nearly 40 years. Yet, the after-effects continue to impact the residents of Gratiot County.
Alma College student Grace Sutherland, a junior from Waterford, in summer research supervised by biology and environmental studies assistant professor Amanda Harwood, conducted a Pine River water and sediment study downstream from the former Velsicol site to determine if there is still evidence of industrial pollution present in the environment.
For her fieldwork, Sutherland collected macroinvertebrates — bottom-dwelling animals that include crustaceans and worms but mostly aquatic insects — at four sites along the river. The bugs and sediment are scooped in a net and transported to the lab for study.
“We are looking for pollution in the sediment, and macroinvertebrates live in the sediment,” says Harwood. “Unlike fish, these bugs don’t travel far; they basically live where they are found. They are brought back to the lab for identification.”
It’s important to identify what is living in the sediment, because some bugs are more tolerant of pollution, and some have different ecological functions, says Harwood. In the lab, Sutherland put healthy lab-grown animals into the collected river sediment and then observed to see if they survived and how fast they grew.
Fish Study: Testing for E. coli Concentrations
In another project, Alma College student Bonnie Hamilton, a junior from Harbor Springs, conducted a fish E. coli study. As evidence shows rising levels of E. coli in the Pine River, Hamilton sought to determine if fish caught upstream of the Alma dam could be safely consumed.
In her summer research project, Hamilton caught fish in areas of high E. coli counts, swabbed the fish specimens in places that humans might typically touch — like the mouth, gills, organs and fillet — and put the samples into an incubator to see if E. coli grows.
“Fish E. coli won’t grow in the incubator, but other animal or human-sourced E. coli will grow,” says Harwood. “Our goal is to determine if there are E. coli concentrations in the fish.”
In another component of this study, Hamilton tested and observed fish caught in cages in the Pine River. Do the fish, which normally have the ability to swim long distances, survive in the cages? If they die, then the evidence may suggest the presence of harmful pollution, says Harwood.