State officials said as much as 6,000 gallons of oil was spilled at the Somers Thin Strip Company.
The NBC Connecticut Troubleshooters dug into public records and discovered that over the years, the same Waterbury factory has had other issues.
In 2010, a worker at the facility was killed while working on a furnace, according to the U.S. Occupational Safety and Health Administration (OSHA).
Eight years earlier, the agency said another worker suffered fractures when his arm got caught in a machine.
The company was fined $7,000 by the feds for what they labeled a "serious violation" and the company settled for $4,000.
Over the years, according to U.S. Environmental Protection Agency records, the company was non-compliant at times with the law regulating the proper management of solid waste.
NBC Connecticut asked the company to comment on these problems but we have not heard back. They did say they "take this situation extremely seriously" and are working tirelessly to address it.