Editor’s note: This story was updated with new information and to correct errors about who issued and served the arrest warrant and the number of charges filed in the case.

The owner of a Vail construction company is facing a felony manslaughter charge related to a trench collapse in Summit County that killed a construction worker in 2021.

Peter Dillon, the owner of the now-defunct A4S LLC, surrendered to law enforcement after a warrant was issued for his arrest Jan. 24, the U.S. Department of Labor stated in a news release.

“There is no excuse for Peter Dillon’s failures to protect workers when federal requirements clearly outline and require safety measures proven to save lives,” Regional Solicitor of Labor John Rainwater said in the news release. “Today’s arrest … cannot recover a life lost in this senseless tragedy but it is a step toward seeking justice for the family.”

In May 2022, the Department of Labor’s Occupational Safety and Health Administration cited Dillon after a worker installing residential sewer pipes suffered fatal injuries when the trench around him caved in, the release states. The construction worker who died was 20-year-old Marlon Diaz. 

Diaz’s family, many of whom live in Honduras, remembered him as a calm, quiet young man who loved to play soccer, according to past Summit Daily reporting. He had moved to the United States not only to create a better life for himself but also to pay for better treatments for his mother, Diana, who suffers from symptoms similar to epilepsy.

The collapse resulted from deteriorating conditions at the project, which A4S LLC could have prevented by using legally required trench-protection systems, according to the Department of Labor. After the incident, other construction workers who worked at the site told Summit Daily that they felt they didn’t receive proper training and that they had safety concerns before Diaz’s death.

The department referred the case to the 5th Judicial District Attorney’s office recommending criminal charges for A4S’s refusal to require safety protection, despite worsening trench conditions, the release states.

OSHA issued three willful citations to A4S for not ensuring the excavation was inspected by a competent person, failing to instruct employees on the recognition and avoidance of unsafe conditions and not having a trench-protection system in place, the release states. Investigators also issued an additional serious citation for not having a safe means of egress within 25 lateral feet of employees working in a trench.

According to OSHA’s report, Dillon said A4S did not have a written safety and health program, and he never conducted safety audits or inspections at his worksites, including the one near Breckenridge where Diaz died.

The agency proposed penalties of about $450,000 and placed the company in OSHA’s Severe Violator Enforcement Program, according to the Department of Labor. A spokesperson for the department said Dillon has paid the penalties, which were reduced to $100,000 as part of a settlement agreement he came to with the agency.

A4S has since shuttered, and Dillon agreed to forfeit any future ownership, leadership or management position that involves trenching, excavation or the oversight of workplace safety and health, the release states.

Collapse and cave-ins pose the greatest threat to trenching and excavation workers, according to the Department of Labor. In 2022, OSHA reported that at least 39 industry workers died, 22 of them in the first six months of the year. Between 2011 and 2018, 166 workers died in trench collapses, the Bureau of Labor Statistics reports.

Trenching standards require protective systems on trenches deeper than 5 feet, and OSHA has a National Emphasis Program on trenching and excavations, according to the Department of Labor.

Dillon was released after posting a $7,500 cash bond Wednesday, Jan. 25, according to the 5th Judicial District Attorney’s Office. His next court date is Feb. 15 at the Summit County Combined Courts in Breckenridge.

OSHA Regional Administrator Jennifer Rouse in Denver said in the release that the tragedy should serve as a reminder to other employers who willingly fail their responsibilities to keep workers safe that the Department of Labor will exhaust every resource to hold employers accountable.

“OSHA has pledged to work with state prosecutors to raise the stakes in appropriate trench death cases,” Rouse said in the release. “And this is an example.”