BRECKENRIDGE, CO – The owner of a Vail construction company facing felony manslaughter charges has surrendered to local law enforcement after the Summit County Sheriff's Office in Breckenridge, Colorado, issued an arrest warrant on Jan. 24, 2023, related to the findings of a federal safety investigation into a deadly trench collapse in November 2021.

In May 2022, the U.S. Department of Labor's Occupational Safety and Health Administration cited Peter Dillon, owner of the now-defunct A4S LLC, after a worker installing residential sewer pipes suffered fatal injuries when the trench around him caved in. The collapse resulted from deteriorating conditions at the project, which A4S LLC could have prevented by using legally required trench protection systems.

OSHA issued three willful citations to A4S LLC 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 protective system in place. 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.

The agency proposed penalties of $449,583 and placed the company in OSHA's Severe Violator Enforcement Program.

The department referred the case to the 5th Judicial District Attorney's office recommending criminal charges for A4S LLC's refusal to require safety protection, despite worsening trench conditions that included at least one trench collapse.

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