A motorist fatally struck an 85-year-old pedestrian in Spring Lake Heights on Saturday, authorities said. It was about 1:20 p.m. when the 70-year-old male motorist turned left from the southbound lane of Old Mill Road onto Allaire Avenue eastbound, fatally striking the female pedestrian as she walked across Allaire, authorities said. The woman was pronounced dead at 1:56 p.m., the Monmouth County Prosecutor’s Office and Spring Lake Heights Police Department said in a joint statement. Neither the victim nor the motorist was identified. Authorities said the motorist remained at the scene and no …