The U.S. Department of Labor’s Occupational Safety and Health Administration has cited three companies after its investigation determined workers died after exposure to hazardous gas at Prospect Ranch in Weld County, Colorado.
OSHA’s investigation found that on August 20, 2025, a pipe in the manure management system at Prospect Ranch LLC disconnected, releasing manure water and hydrogen sulfide gas. Contractors Fiske Inc. and HD Builders LLC were hired to perform work on the system. A Fiske employee and a Prospect Ranch employee attempted to stop the flow but were overcome by the gas. Subsequently, three more Fiske employees and one Prospect Ranch employee entered the pump room, which led to the loss of a total of six workers. HD Builders employees were present but unharmed.
OSHA cited Prospect Ranch LLC for serious violations including failure to protect workers from atmospheric hazards, have a written hazard communication program and train workers on methods to detect hazardous gases. The company faces $132,406 in proposed penalties.
The agency also cited Fiske Inc. for serious violations including failure to protect employees from hazardous atmospheres, and failure to provide hydrogen sulfide detection training. OSHA proposed $99,306 in penalties. HD Builders was cited for violations including failure to have a written hazard communication program and failure to provide training on detecting hydrogen sulfide for which OSHA proposed a $14,897 penalty.
The companies have 15 business days from receipt of their citations and penalties to comply, request an informal conference with OSHA, or contest the findings before the independent Occupational Safety and Health Review Commission. Penalties and citations may be adjusted throughout the course of the case. Please check the OSHA establishment search page periodically for any changes in the inspection or penalty status.
Employers can also contact the agency for information about OSHA’s compliance assistance resources and for free help on complying with OSHA standards.