Firefighters who took part in a rescue exercise at The Boring Company’s Las Vegas tunnel project suffered from chemical burns relating to materials used during excavation and lining, records and accounts reported by Fortune have shown. The accident has revived questions about the disclosure of hazards, training, and oversight at the high-profile tunneling venture founded by Elon Musk.
What Was Supposed To Happen During The Drill
Firefighters from Clark County, as part of a planned emergency drill to fine-tune tunnel rescue operations, ventured into the construction site. In the course of the drill, workers found pools of slurry — in common parlance, “muck” — created when groundwater and soil mingle with cementitious accelerants used to solidify tunnel liners. Several firefighters complained of skin irritation when muck that had soaked into their boots was rinsed out; they were taken to a hospital and found to have chemical burns. Fortune reported that some of the injuries left long-lasting scars and that tunnel workers had suffered similar burns in the past.
The Boring Company has said that its crews tried to clean up residue ahead of the training, but not all affected areas could be cleared. Company executives also insisted the fault lay with the fire department following its training plan. Nevada’s state workplace-safety agency opened an investigation in the wake of the drill.
The Chemicals Used and the Tunnel Construction Method
Tunnel projects often use accelerators and shotcrete — a slurry blasted against the tunnel wall — that help chirp the deadening sound of trains racing by, speeding up since they no longer have to contend with sharp curves. A lot of accelerators and wet cement products are highly alkaline and, when mixed with water or other soil, will produce a caustic material. According to NIOSH guidance, wet concrete has a pH value of 12–13 and is extremely caustic, capable of causing deep tissue burns with prolonged contact. Burns can continue to develop after exposure has ceased, if residue from phosphorus remains on the skin or is embedded in clothing (or boots).
Best practice also includes clear hazard communication; impervious PPE (e.g., boots and gaiters); regular decontamination; and flushing of exposed skin (ideally followed by thorough washing with soapy water). In multi-agency drills, ICs tend to brief participants on site-specific chemical dangers and will check beforehand whether known hazards have been recognized, controlled, or isolated. In the close quarters of tunnels, small failures in communication or cleanup can escalate into preventable injuries, experts say.
Citations Issued and Later Withdrawn by Nevada OSHA
In the wake of the incident, Nevada OSHA issued three “willful” violations — the most serious classification — and proposed $425,595 in fines against The Boring Company, according to documents cited by Fortune. A willful violation claims the employer knew it was violating requirements of law or that it was plainly indifferent to worker safety.
Records indicate the company’s top leadership wasted no time in reaching out to powerful state officials. Fortune said that The Boring Company’s president, Steve Davis, spoke with the governor’s infrastructure lead and later met with senior Nevada officials. The citations were subsequently vacated — an unusual move in the telling of former OSHA officials Fortune interviewed — outside of the standard appeals process. The state agency later admitted to documentation errors in the case file and reinstated mentions of those meetings after discrepancies were flagged.
Safety Culture and Accountability at The Boring Company
The Boring Company has faced repeated brushes with scrutiny over injuries on the Las Vegas project, including a recent severe crush injury that brought work to a temporary halt. Here are links to the reporting: Fortune’s story says employees have been complaining for years of accelerator-related burns. The pattern raises the stakes for uniform hazard communication under state-plan OSHA rules, as well as coordination with local responders such as the Clark County Fire Department.
Based on hazard communication standards, employers are to identify the risks associated with chemical exposure; train workers; and provide appropriate PPE and decontamination practices. Where public forces are engaged in on-site rehearsals, the same risk management procedures would usually apply to visitors and collaborating response organizations. Tunnel rescue guidelines from national safety groups call for joint pre-planning, for repositories of chemicals at points of entry, and physical exclusion areas around contaminated zones — especially where caustic slurry can settle.
What to Look for as the Vegas Loop Project Develops
The injuries — and the atypical treatment of citations for the accidents — could leave a bad taste in public confidence as The Boring Company pushes for approvals to expand its Vegas Loop beyond the convention center corridor.
And even with a withdrawal of state citations, project sponsors frequently encounter stricter permit conditions, more frequent inspections, and ordered safety improvements in the aftermath of high-profile accidents.
Signs to watch for include whether Nevada OSHA performs follow-up inspections, if Clark County insists on updated plans for rescuing workers and responding to chemical hazards at future drills, and how well emergency personnel are able to prepare for tunnel conditions. Simple measures — such as testing the pH on site before putting troops through exercises, pre-staging decontamination stations, and providing drill participants with sealed, over-the-boot protective wear — could significantly reduce risk, safety practitioners say.
For a project that prides itself on speed and spectacle, the way forward may depend not on the most glamorous work but on methodical documentation of all that has been done to date, transparent collaboration with regulators and first responders, and meticulous control of chemical exposures. If those fundamentals get stronger, then as the Vegas Loop grows and grows, it can do so more efficiently — and with the people who help keep them safe from harm protected.