FARMINGTON — It’s official: The opening of all seven schools in the Mt. Blue Regional School District will be delayed until Sept. 6, Superintendent Michael Cormier announced late Thursday afternoon.

School had been scheduled to start Aug. 31 for students in pre-kindergarten to grade nine and on Sept. 1 for grades 10-12. Now, classes will begin on Tuesday, Sept. 6, for students in pre-kindergarten to grade nine, and Wednesday, Sept. 7, for students in grades 10-12.

Three student days will be added to the end of the school year. School is now scheduled to get out on June 13, with no snow days.

Cormier made the decision because work on the new Mt. Blue High School and the Foster Career & Education Center is behind schedule and the grounds are a fully active construction site.

Problems include demolition of parts of the old school still ongoing this week; 77 geothermal wells must be drilled; and the renovation and new construction at the new wing of the Foster Center that was set to open this fall is not ready, Cormier told the school board this week.

The extra time also will allow contractors to complete a “punch” list of uncompleted contract items at the new W.G. Mallett School. And it will give staff there more time to set up their rooms.

Cormier mentioned the carpeting for the library, for example, was en route from the South, so books could not be shelved.

At Tuesday’s school board meeting, directors authorized Cormier to make the decision by Friday on whether to delay opening day if he felt the high school was not ready for students.

“This gives me great peace of mind,” Director Betsy Hyde of Temple said Tuesday. “I drove by (the school) and did not feel it was going to be safe for the students.”

In an email sent to staff Thursday, Cormier announced the following schedule adjustments:

* The staff workshop set for Monday, Aug. 29, will be held but will be moved to Mt. Blue Middle School.

* Tuesday will remain the regularly scheduled staff workshop day.

* If there is extreme weather due to Hurricane Irene, Monday’s workshop will be moved to Tuesday and Tuesday’s workshop moved to Wednesday. The change would be announced on the district website, www.mtbluersd.org.

* It is anticipated teachers in the new wing at the Foster Center and in the 21 portable classrooms at the high school will be able to get into their classrooms by early next week.

“Furniture is arriving daily and is being set up,” Cormier wrote. “It will still not be completely finished, but I believe it will be very usable by Sept. 6.”