A hazardous materials incident occurred Thursday evening on Oil Field Road in Brenham when a water well drilling operation struck an unexpected oil pocket, releasing a dangerous hydrogen sulfide gas leak—alongside an unexpected oil pocket.
The incident occurred around 6:40 PM at 9920 Oil Field Rd. when crews hit the volatile gas during drilling. In response, the City of Brenham Fire Department, Washington County Office of Emergency Management (OEM), and multiple agencies quickly mobilized to assess and contain the threat. HazMat teams from College Station were also dispatched to assist. As a precaution, after the release of the hydrogen sulfide leak, authorities issued a shelter-in-place order for residents in the immediate area, guided by a plume model tracking gas dispersion. Officials closely monitored the air quality to determine whether evacuation would be necessary. By 7:20 PM, crews successfully plugged the wellhead, and gas levels returned to zero. Officials then lifted the shelter-in-place order, and the area was declared safe for residents.
What is Hydrogen Sulfide (H₂S)?
Hydrogen Sulfide is a colorless, flammable gas known for its distinct rotten egg odor at low concentrations. It is commonly found in natural gas, petroleum, and in areas with decaying organic matter—such as sewers or oil fields.
While low levels may cause irritation to the eyes, nose, and throat, exposure to higher concentrations can be extremely dangerous and even fatal. Symptoms of H₂S exposure include:
- Headache and dizziness
- Nausea and vomiting
- Breathing difficulty
- Confusion
- Loss of consciousness
- At very high levels, exposure can result in instant respiratory failure
Officials urged residents to always take shelter-in-place and evacuation orders seriously due to the rapid and severe health risks associated with hydrogen sulfide exposure. The Washington County OEM thanked residents for their cooperation and confirmed that ongoing monitoring would continue to ensure public safety.
