The Municipality of Chatham-Kent announced that contractors who were drilling for new monitoring wells in Wheatley struck a pocket of hydrogen sulphide gas 85 feet below the surface at 11:05 a.m. on Sunday.
"A mobile vent stack system at the site of the well drilling was successfully deployed which allowed the gas to vent to the atmosphere without incident," said Chatham-Kent’s General Manager of Infrastructure and Engineering Services, Thomas Kelly.
Kelly said this is the first of two monitoring wells to be installed.
"One well will reside inside the investigation area and the second just outside the evacuation zone. These wells will allow the investigation team to obtain groundwater and gas samples to support the chemical modelling work," he added.
Chris Case, the Fire and Emergency Service Chief credited a well-designed and practised safety plan with ensuring the incident was handled successfully.
It's reported that drilling was stopped and the crew moved out of the hot zone after connecting the well. On-site hazmat and technicians then moved in to check that the area was safe while fire crews and technicians began mobile monitoring around the area.
No injuries were reported.
"We were advised that the event had concluded and that apart from the detectors close to the drill site no gas had travelled creating a risk to the community. All response teams were stood down around midday and the engineers have returned to work. I am pleased to advise that the plans, which are practiced and drilled regularly, worked," Case said.
Case added that the incident demonstrates the unpredictable and potentially dangerous conditions that can occur.
He said that he supports the cautious approach taken to only allow access to properties when work is not underway.
