The high school in Naugatuck closed for the second time on Friday due to an odor-related problem.
School officials told Eyewitness News that they do not the source of the smell, but that the closure was just a precaution.
The school was closed last Friday as well after a malfunction of some pumps caused a sewage backup in the kitchen grease traps.
A waste water treatment facility was brought in to clean it up, school officials said.
This week, they said they did not know if a back up in the kitchen is the same reason for the odor.
They also said they did not want to take any chances with students and staff.
All of the other schools in the borough are running on a normal schedule.
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