MOUNT PLEASANT, Wis.—Six miles west of Lake Michigan lies a cleared building site half again as big as Central Park, ready for .

Contractors have bulldozed about 75 homes in Mount Pleasant and cleared hundreds of farmland acres. Crews are widening Interstate 94 from Milwaukee to the Illinois state line to accommodate driverless trucks and thousands of employees. Village and county taxpayers have borrowed around $350 million so far to buy land and make infrastructure improvements, from burying sewer pipes to laying storm drains.

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