RIDGEFIELD PARK, N.J. — Hartz Mountain has begun construction on the 140-room Hilton Garden Inn at Overpeck Centre in Ridgefield Park. The five-story hotel, located at 70 Challenger Rd., will feature a business center, a workout facility, and a restaurant and bar. Construction is set to be complete fall 2008. Overpeck Centre is a mixed-use development set on 60 acres along the waterfront. It contains more than 1 million square feet of office space and a 12-screen theater.