This repository contains data and findings for a collaboration between MuckRock and the Cicero Independiente called “The Air We Breathe.”
You can find our earlier work on Chicago's air quality in chicago-air-quality-automated. More data and analysis driving the investigations of MuckRock's news team are cataloged in news-team.
Several of the data files used in this analysis were too large to host on GitHub. You can download our data folder directly as zip file. If you have forked this repo, you can store the data folder in the root directory, cicero-koppers-air-pollution, to access the data files from our etl and analysis folders.
Through an open-records request to the Illinois Environmental Protection Agency, MuckRock and the Cicero Independiente received Illinois emissions inventory data from 2012 to 2021, for 141 pollutants released at more than 1,000 facilities in Cook County.
We copied the Illinois EPA pollutant codes and stored them in data/manual/pollutant_code_crosswalk.csv to use in analysis. The raw data from our request is in the file data/raw/foia_reported_emissions_2012-2021.csv and is used in analysis/findings_notebook.qmd to calculate the average annual pollution of Koppers compared to other polluters in Cook County from 2012 to 2021.
After analyzing the amount and types of emissions from Koppers in Cicero, we compared the plant to others nationally using the federal EPA’s Toxics Release Inventory. We pulled 10 years’ worth of the Basic Plus Data Files, from 2012 to 2022.
The raw data files are in data/raw/toxic_release_inventory/. In etl/prep_tri_data.R, we then concatenated the years together and filtered the data to focus on the column 115_total_air_emissions, which is the total air emissions for the facility, for several hazardous or cancer-linked chemicals, including those also emitted at Koppers: benzene, naphthalene, phthalic anhydride, maleic anhydride, quinoline, styrene and creosote.
We chose those pollutants after speaking with three environmental health experts and reviewing each pollutant that Koppers emits to check its carcinogenic classification in the file data/manual/koppers_pollutants_cancer_check.csv.
The filtered data was exported to data/koppers_tri_pollutants.csv and used in analysis/findings_notebook.qmd to assess how Koppers compares to other facilities across the country that report their emissions in the Toxics Release Inventory.
You can find a data dictionary for TRI's Basic Plus Files in data/dictionaries.
We used the federal EPA’s national air toxics risk assessment based on emissions inventories, now called AirToxScreen, to identify census tracts in Cicero that face an elevated risk of cancer from benzene and naphthalene. We downloaded the 2019 AirToxScreen National Cancer Risk by Pollutant (xlsx) file and stored it in data/raw/2019_National_CancerRisk_by_tract_poll.xlsx before loading it into etl/prep_tract_analysis.R to filter the data file and make it smaller, so it could be used in analysis/findings_notebook.qmd to compare the cancer risks from benzene and naphthalene in Cicero to census tracts across the country.
As a publicly-traded company, Koppers is required to report all stock transactions by its senior executives and large shareholders to the U.S. Securities and Exchange Commission in filings called a "Form 4."
We exported all SEC Form 4 filings for Koppers from Jan. 1, 2006, through Dec. 31, 2023, to identify trends in different types of transactions by these so-called "insiders."
- We then sorted the stock sales to the transaction code, "S," which is defined as the "open market or private sale of non-derivative or derivative security"
- Then we grouped these sales by month and quarter to look for trends, and referred to material disclosures and other public company information to determine if the transactions were related to changes in stock price or company leadership changes
- The data was then shared with several accounting experts who specialize in Form 4 reporting requirements, for analysis and interpretation
You can find the data in data/manual/insider_trades.csv and you can access all Koppers Form 4 filings, and other corporate documents, through the SEC's EDGAR portal.
In etl/geocode.R, we geocoded facility addresses from the Illinois EPA Air Emissions Inventory using Google's Geocoding API, which we then exported to data/processed/aer_lat_longs.csv and then used in analysis/map_eda to generate maps of polluters by pollutant that formed the basis for our illustrated map of Cook County's benzene and naphthalene polluters in the story.
Contact Dillon Bergin at dillon@muckrock.com.