For the first time in Washington state history, an employer faces felony charges for a workplace fatality.

Harold Felton, 36, died in a January 2016 trench collapse at a West Seattle residential sewer-line project. Phillip Numrich, 40, then-owner of Alki Construction, now faces second-degree manslaughter charges, filed on Jan. 5 by the King County Prosecuting Attorney’s Office.

The Washington Dept. of Labor & Industries’ investigation into the death led to $51,500 in fines and citations for safety violations, including a willful violation, considered the most severe.

“There are times when a monetary penalty isn’t enough,” Joel Sacks, the department’s director, said in a statement. “This company knew what the safety risks and requirements were and ignored them. The felony charges show that employers can be held criminally accountable.”

Felton was working in a 7- to 10-ft-tall, nearly 2-ft-wide trench when the dirt walls collapsed and buried him, but rescuers were unable to dig him out in time. There was no system in place to prevent the walls from caving in, department documents say. Alki Construction received one willful, five serious and one general violation in connection with the incident. The charges state that Numrich identified the soil as Type C, the most unstable, and that the trench was left open for 10 days, during which it rained multiple times. Further, Felton used handheld vibration tools inside the trench.

Alki’s willful violation was for not ensuring that a 4-ft-deep or deeper trench had a protective system in place to prevent the dirt sides from caving in. “Numrich’s conduct substantially deviated from any known or recognized safety standard and from the standard of care that any reasonable person would exercise in the same situation,” according to the Dept. of Labor & Industries’ investigation, cited in the charges.

Records show Numrich’s Alki Construction has gone out of business; he now owns Alki Sewer. Messages seeking comment were unanswered by Alki Sewer.