United States v. Didion Milling, Inc., et al.

On March 19, 2024, a court sentenced Didion Milling, Inc., (DMI) Supervisor Nicholas Booker to serve three years’ probation. Brooker pleaded guilty to one count of falsifying cleaning records and one count of falsifying environmental records (18 U.S.C. 1001(a)(3)). Booker is the final defendant to be sentenced in this case involving a catastrophic explosion that killed and wounded several DMI employees.

DMI owned and operated a corn mill in Cambria, Wisconsin. Corn dust is combustible and can fuel explosions if exposed to an ignition source and mixed with a sufficient concentration of air. Regulators required the company to operate “baghouses,” equipment designed to prevent particulate matter, such as corn dust, from being released into the environment from the corn mill. From at least 2015 to May 2017, DMI employees, including shift workers and shift superintendents, made false entries in the mill’s “baghouse logs,” disguising data meant to monitor and document whether the mill’s baghouse equipment was working properly to filter particulates from the air. DMI environmental manager provided baghouse logs for 2015, 2016, and 2017 to environmental inspectors, knowing that they contained false entries.

 The company was also required under Occupational Safety and Health Act safety standards to develop and implement a housekeeping program to reduce the accumulation of fugitive grain dust within its corn mill. DMI maintained a “master sanitation schedule” logbook listing each of the required dust cleanings and the specific dates by which the cleanings were supposed to be completed. The sanitation logbook contained spaces for employees to record that the dust cleanings had been performed and that documentations procedures had been followed.

On May 19, 2017, employees falsely initialed, signed, and dated entries in the sanitation logbook for the week of May 1 through May 7, 2017, giving the appearance that the required dust cleanings were performed when they had not been. The company provided the sanitation logbook containing the false May 2017 dust cleaning entries to the Occupational Safety and Health Administration (OSHA) during its investigation of the explosion.

A court sentenced DMI on January 25, 2024, to pay a $1,000,000 fine, complete a five-year term of probation, and pay $10,250,00 in restitution. The company pleaded guilty to falsifying OSHA and EPA records (18 U.S.C. § 1001(a)(3)).

The following employees were sentenced between February 15 – 16, 2024: Former Environmental Manager Joseph Winch was sentenced to two years’ incarceration, followed by two years of supervised release. Winch also will pay a $10,000 fine. Former Shift Superintendent Joel Niemeyer was sentenced to pay a $1,000 fine and complete a one-year term of probation. Supervisor Michael Bright was sentenced to complete a one-year term of probation. Vice President Shawn Mesner was ordered to serve 24 months’ incarceration, followed by one year of supervised release, and pay a $5,000 fine. Food Safety Superintendent Derrick Clark will also serve 24 months’ incarceration, followed by one year of supervised release. Shift Supervisor Anthony Hess was ordered to pay a $5,000 fine and complete a one-year term of probation.

A jury convicted Mesner and Clark in October 2023 for their role in a catastrophic explosion in May 2017 at the DMI corn milling facility in Cambria, Wisconsin, that killed five employees and wounded others. Specifically, Mesner was convicted of a fraud conspiracy and conspiracy to commit federal offenses (18 U.S.C §§ 1349, 371). Clark was convicted of conspiracy to commit federal offenses, document falsification in contemplation of a federal investigation, false entries in a record within the U.S. EPA jurisdiction, and obstruction of an agency proceeding (18 U.S.C. §§ 371, 1519, 1001 (a)(3), 1505). Niemeyer and Winch pleaded guilty to conspiring to falsifying documents in matters under the jurisdiction of OSHA and EPA (18 U.S.C. § 371). Hess pleaded guilty to obstructing an OSHA proceeding by making false statements to OSHA and the Department of Labor (18 U.S.C. § 1505). Bright and Booker pleaded guilty to making false statements (18 U.S.C. § 1001(a)(3)).

The U.S. Environmental Protection Agency Criminal Investigation Division and the Wisconsin Department of Natural Resources conducted the investigation.