The carcinogenic compound trichloroethylene (TCE) is a byproduct of many manufacturing processes, and it is difficult to clean up when spilled. In the summer of 2018, residents of a Milwaukee apartment building were evacuated when inspections revealed unsafe levels of the chemical were still present from the site’s previous industrial occupants.
A Milwaukee Journal Sentinel investigation revealed over 800 other current and former cleanup sites in Milwaukee County, including almost 300 residential addresses. In order to help residents make informed choices about their health, we mapped these properties using a custom browser application.
To get a full picture of the scope of the problem, I wrote and ran a web scraper that gathered a clean data dataset from the state Department of Natural Resources’s public records about industrial waste cleanup sites. I analyzed these sites using QGIS to give summary statistics and clustering information to the reporting team working on the investigation.
Finally, we visualized these sites using MapBox, allowing users to view the latest DNR records for each affected property.
Completed: August 2023
Published by: The Milwaukee Journal Sentinel
Technologies used: HTML, CSS, & JavaScript (MapBoxGL.js) / MapBox Studio / Python (BeautifulSoup, Pandas) / QGIS
Andrew Steven Hahn 