U.S. Steel failed to test a Lake Michigan tributary for a potentially carcinogenic chemical after a spill from one of the company's plants in northwest Indiana, documents show.
The October spill was the second time this year that the company's Portage plant dumped chromium into Burns Waterway. Plant managers told an inspector in November that they had opted not to test for the most dangerous form of the metal after that spill, according to an inspection report posted online Tuesday by the Indiana Department of Environmental Management, the Chicago Tribune reported.
Steel mills are required to regularly administer two types of tests for chromium, which is used to make steel alloys rust-resistant. One test measures total chromium, including a significantly less toxic form known as trivalent chromium. The other tests for hexavalent chromium, which was made infamous by the movie "Erin Brockovich."