Construction on the town’s first synthetic-turf athletic field is scheduled to begin next month at Foxborough High School and wrap up in October. At a Special Town Meeting in December, voters approved the first phase of the $1.6 million project, which will use surplus funds from the high school construction project. Turfs Up, the all-volunteer local group behind the effort, has spent four years lobbying for the field in the town, which is one of the last in the area to get one. Current baseball and softball fields at the high school are to be moved to the back of the school so the new field can be constructed in the front. Along with the high school surplus funds, the field is being built with $200,000 from town and school funds, a $200,000 NFL grant, and donations of money and time, including all the engineering and design plans.