A half-dozen Regional School Unit 71 buses were taken off the road March 6 after a surprise inspection by Maine State Police troopers, who deemed the vehicles "unsafe to drive."

Less than a week later, the district had replaced its transportation director and mechanic with interim appointees and was conducting an investigation into the failed inspections.

Speaking March 11, Superintendent Mary Alice McLean said RSU 71 Director of Transportation and Maintenance Kevin McAvoy is on leave "pending the investigation." She declined to give additional details, including the status of the mechanic, whom she did not identify, but said the three interim appointments are related to the investigation.

Christine Stevens is currently the interim transportation director, Scott Packer is interim maintenance director and Tim Nesbit is interim mechanic. McLean said all three appointees were previously employed by the district.

After the surprise inspection March 6, McLean posted a letter to the district's website cancelling after-school activities and temporarily consolidating bus routes. The change, she wrote, affected students in Searsmont, Belmont, Morrill and Swanville.

She went on to say that she will be proposing structural changes in the areas of transportation and maintenance in the school district. In a later message, she said she plans to propose additional staff in the transportation department.

"The safety of our all of students is my highest priority as well as the the timely and reliable transportation of students to and from school and school activities," McLean wrote.

The failed inspections are the second bus-related problem in the district in recent months. In January, McLean closed Nickerson school in Swanville for a day because the district did not have enough substitute drivers to cover the daily bus routes.

Reporter Fran Gonzalez contributed to this story.