Joel Barlow High School will remain closed today after a contractor accidentally added fuel oil to the water storage tank, officials announced Thursday evening.

Superintendent Dr. Jason McKinnon said the school will remain closed Friday while companies clean up water storage tanks.

McKinnon said the goal is to reopen the school safely as soon as possible.

Officials said a contractor poured approximately 20 gallons of fuel oil into the school’s 20,000-gallon water storage tank on Tuesday.

Kitchen staff reported an odor on Wednesday morning, which prompted for class to be dismissed at around 12:30 p.m.

The school contacted environmental companies to develop a plan for cleaning, as well as the Department of Health.

McKinnon said most after-school activities have been canceled for Friday.

The high school administration will communicate to students and staff concerning special events and will continue to provide updates daily as the situation unfolds.