Work will begin soon on the first phase of the Dover-Sherborn Athletic Campus Master Plan, which involves replacing the stadium’s grass playing field with synthetic turf. The work will start after Tuesday, the last day of high school exams. The Dover-Sherborn Boosters has already raised more than $1 million for the first phase of the project, which will also include making minor drainage improvements at the track and regrading another field. Work should be complete by September, according to a the club’s website, www.dsboosters.com. The plan, approved the Dover-Sherborn School Committee in January, is being funded by private donations through the boosters organization. The next phase of the approximately $3 million project, to be done over the next three or four years, will include moving four tennis courts and adding two new ones, improving baseball and softball fields, and reconstructing the Junction Street field, according to the organization’s website. The final phase includes creating two new multipurpose fields on Farm Street.