WALES — Officials in Regional School Unit 4 are considering three plans for the new school year: all virtual, all in-person or a mix, possibly with certain grades going to school virtually and others going in person.

The plan will depend on guidance from the Maine Department of Education. The department has said it will create a three-tiered health advisory system to help schools decide whether or not to bring students back to classrooms. The system will be color coded — red, yellow and green — and will take into account public health by county. Red school systems might want to go all virtual, while green school systems might hold all in-person classes. Color codes are expected to be regularly updated and changed.

The Maine Department of Education is expected to present the color codes at the end of July.

RSU 4 includes three towns in two counties. It is unclear how it will be color coded.

“Student and staff safety are our No. 1 priorities,” Superintendent Andrew Carlton said. “It really is going to depend on what the color comes out, what the guidance is and what do we have the capacity to do.”

Carlton’s biggest concern at the moment: busing. The school system has just over 1,400 students from prekindergarten through grade 12 and it will have to keep students spread out not only in classrooms but also on their way to school.

“What do we have for busing capacity? And come the end of the month, early August, what’s that going to be?” Carlton said.

RSU 4 has formed ad hoc committees and teams to help craft plans for the new school year. While all plans are still tentative and based on guidance from the state, one potential plan would have students prekindergarten through grade 5, and possibly students in grades 6 and 9, going to school buildings while students in other grades would learn remotely.

School system officials hope to announce a firm plan the second week of August.

School is slated to begin at the end of August, but Carlton said that is subject to change.

RSU 4 includes Sabattus, Litchfield and Wales.