Editor’s Note: This article has been updated to correct the year that the trench collapse occurred.

Before 20-year-old Marlon Diaz died in a trench collapse at a construction site in Breckenridge on Nov. 16, 2021, the project manager reportedly voiced safety concerns to the owner of A4S Construction, the company doing the work.

Employees working in the site’s trenches complained to the owner that they did not feel safe after dirt and rocks kept falling on them. Two weeks before the fatal collapse, a trench at the same worksite partially collapsed. 

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About two hours before the walls caved in, the owner of the Vail-based company, Peter Dillon, entered the trench himself, but reportedly failed to note that it was improperly dug and lacked the required safety equipment. 

Then, even after the workplace death, employees worked in the trenches without proper safety precautions for at least another month.

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All that is according to an affidavit in support of an arrest warrant filed in Summit County Court when prosecutors charged Dillon with manslaughter late last month. Written by an investigator for the 5th Judicial District Attorney’s Office, the affidavit draws from a death investigation completed by the Summit County Sheriff’s Office and reports from the U.S. Department of Labor’s Occupational Safety and Health Administration.

“Employee testimony, photographs, and video obtained by OSHA portray a pattern of unsafe behavior on the Project in the months leading up to the fatal incident,” the document states.

After turning himself into authorities on a warrant issued Jan. 24, Dillon posted a $7,500 cash bond and was released. He appeared in court for the first time on Tuesday, Feb. 14. Judge Edward Casias set a dispositional hearing in the case for March 22.

Before Dillon’s arrest, OSHA issued three willful citations and a serious citation to A4S Construction for safety failures and proposed about $450,000 in fines. Dillon accepted the citations and eventually settled for reduced penalties totaling $100,000. 

A lawyer representing Dillon declined to comment Wednesday.

Three workers buried

The construction crew was nearing the end of their day Nov. 16, 2021, according to the affidavit, when the lead excavator for A4S Construction, who was operating machinery near the trench where three employees were installing pipe, saw the trench wall crack — then collapse.

The lead excavator reportedly started honking his horn to draw attention before jumping from the vehicle and running to the trench, followed by another employee. As they entered the south end of the trench by ladder, the affidavit states, the two were knocked down by a secondary collapse.

Once again on his feet, the lead excavator ran toward the location of the crew and began digging, according to the affidavit, which states that Dillon joined him a short time later. The two reportedly freed one employee right away and learned that two others were buried above their head.

As Dillon dug, the buried employees squeezed the lead excavator’s hand — indicating that they were responsive under the dirt — but ultimately only one employee was freed, according to the affidavit. 

The trench collapsed around 4 p.m. and rescuers did not recover Diaz’s body until about 6:30 p.m. Dillon had been on site that day and had entered the trench around 2 p.m. without commenting on the lack of proper sloping or safety equipment, according to the affidavit.

The trench where workers had been installing pipe was reportedly about 115 feet in length and between 10 and 13 feet deep. According to court documents, A4S Construction had about 10 employees and had been contracted to install water and sewer lines at the residential project at 84 Berlin Placer Road in Breckenridge.

Investigators say A4S Construction began work at the site on Nov. 16, 2020, exactly one year before the fatal incident. Weekly reports provided by A4S indicate employees first entered trenches on Aug. 31, 2021, and worked for at least four months in unprotected trenches, according to the affidavit.

Dillon had hired a project manager and a lead excavator operator — who he said were in charge of training the crew and communicating and enforcing safety requirements —  to help oversee the worksite, according to the court document. 

Investigators say the project manager and lead excavator, however, offered them a different account of their responsibilities. Court documents claim that the project manager and lead excavator had never received formal training on trenching and excavation regulations, had little to no familiarity with trench protective systems and were sometimes unable to explain fundamental trenching concepts such as soil typing.

The project manager did hold daily safety meetings, according to the affidavit, but the company kept no records of topics discussed. The project manager reportedly told investigators he didn’t think the crew understood the hazards of trenching and “didn’t seem to take it seriously.”

A4S Construction did not have a written safety and health program, never conducted audits or inspections on worksites, did not offer formal, written training, or maintain any records documenting which employees had received training, according to the affidavit. Dillon reportedly told investigators that most employees “acted like they had been trained before.”

The project manager told investigators, according to the court documents, that it was not his job to be the “daily safety monitor” and claimed that he had raised concerns early on with Dillon that the project’s lead excavator operator did not know much about trench safety, including the proper way to slope trench walls.

The lead excavator, meanwhile, told investigators he was never advised that he was in charge of trench safety and that he had no prior experience digging or working in trenches, never received any training related to trench safety, and was not familiar with related regulations, according to the affidavit.

Dillon did not provide a trench box — a piece of safety equipment often required for trench work — until early September 2021, the lead excavator reportedly told investigators. Even then, the lead excavator said the box — which was too small for most of the trench work being done and too heavy to move with most of the equipment on site — was used only for about a week, mostly after employees complained they did not feel safe because of falling dirt and rocks, according to the affidavit.

Many of the crew members primarily spoke Spanish and were unable to communicate directly with Dillon or the project manager, court documents state, leaving the lead excavator — who is reportedly bilingual — to translate. 

Investigators say the lead excavator disputed Dillon’s claim that workers had received prior training at other jobs and told investigators that “pretty much everyone that went in the trench complained” but the crew felt like they had no choice to work in unsafe conditions “because they had to feed their families.”

Diaz — who had moved to the United States from Honduras just 10 months before the fatal trench collapse — had left his home not only to make a better life for himself, but to send money home to support his parents and pay for treatment of his mother’s epilepsy symptoms, his family previously told Summit Daily.

At the time of his death, the trench box was located outside another trench a few hundred feet away and had never been used in the trench that collapsed, the affidavit states. In a news release announcing the manslaughter charge against Dillon, the Department of Labor described Diaz’s death as “preventable.”

After the collapse

Throughout construction, the project manager provided weekly reports to Dillon that included photographs showing at least 10 different employees working in trenches over 10 feet deep without safety measures on 14 different occasions, according to the affidavit.

At least four of those reports contained photographs of unsafe conditions — including on Dec. 4, Dec. 8, Dec. 21, and Dec. 23 in 2021 — that occurred after the fatal trench collapse. Another photograph taken Nov. 30, 2021, shows improper placement and use of the trench box, the court document states.

As part of his legal settlement with the Department of Labor, Dillon agreed not to directly or indirectly own or perform management or supervisory roles at any construction or excavation business. If he does resume activities in the construction industry, he will be required to notify the department and complete extensive training related to trenching and excavation standards.

“Based on his 30 years of experience and training in the construction industry, Dillon knew that conditions did not comply with OSHA regulations,” the affidavit states. “And he took no steps to correct conditions, or remove employees from unsafe conditions before the trench collapse and even after the trench collapse.”