New signs with an estimated 20-year life span and more readable will be installed along I-75 this summer on the 63-mile stretch of highway between St. Ignace and Sault Ste. Marie. Signs also will be replaced along business loop I-75 in St. Ignace.

The sign project is estimated to cost $1,610,000 and is scheduled to be completed by this October, said Karrie Abbitt, project engineer with Michigan Department of Transportation (MDOT) in Newberry.

The state's new minimum speed limits, which allow a fivemile per-hour increase for trucks, will also be posted this summer, she said.

The minimum speed has changed from 45 miles per hour up to 55 miles per hour. Also, truck speeds have been moved up to 60 miles per hour from 55 miles per hour, said Mrs. Abbitt.

She said shoulder closures would take place where crews are working and she does not anticipate any lane closures while I-75 signs between St. Ignace and Sault Ste. Marie are replaced. Action Traffic Maintenance of

Flint, the contractor on the job, began drilling holes for new sign posts last week.

The most notable difference for drivers is the new lettering style used on the signs, said Mrs. Abbitt. Lettering will be in a font called Clearview and signs will be 20 percent larger than their predecessors, she said.

David Deatrick, senior MDOT inspector from the Newberry office, said the new signs also will have new posts made either of steel or wood, depending on the size of the sign. The height, width, and wind load of a sign determines if wood or steel posts are used, he said.

The posts will be set in a breakaway foundation, allowing the sign to fall away from a vehicle if the sign is hit.

During the preparation work, Mr. Deatrick said that crews will dig new holes for the signs using an auger. Each sign will have two posts and the anchor hole will be two feet in diameter and seven feet deep. Once the hole is drilled, a metal circular form is dropped into the pit to keep the wall from collapsing before it is filled with reinforcing concrete,