TERRE HAUTE, Ind. (AP) — Indiana State University's plan to demolish two 45-year-old towers is expected to cost about $4 million and could begin by the end of the year.

The project to raze the 15-story Statesman Towers will require state approval because of its cost, according to the Tribune-Star. ISU Vice President for Business Affairs Diann McKee said she doesn't expect it to go out to bid until this fall.

The buildings were erected in 1968 and have been used as residence halls and academic buildings. They contain a total of 320,000 square feet of space, but ISU officials say they are expensive to maintain and aren't energy efficient.

The method of demolition hasn't been determined. ISU is working with Schmidt and Associates to determine the most cost-effective way to bring down the towers, according to McKee and Bryan Duncan, ISU's director of capital planning and improvements. Options include implosion or use of a crane and wrecking ball.

Floor tiles containing asbestos will be removed before demolition occurs. Metal, doors, electrical items and other materials will be recycled, and utilities running through the basement will be relocated.

"A lot of salvage work is involved," Duncan said. "It's kind of a complicated project."

Duncan said the demolition project will have to address the proximity of the Debs Museum. He said demolition crews likely will install a barrier and some sort of cover to protect the museum from flying debris.

Duncan said the demolition work could take four to six months once it begins.