Massachusetts Land Court Judge Gordon H. Piper ruled last month that Tabor Academy must obtain a special permit from the town to put up 90-foot-tall light poles on the athletic fields constructed last year by the private school. The fields were built despite objections and cease-and-desist orders from the town, which had cited environmental concerns over the materials used to build the fields, and their proximity to Sippican Harbor. Tabor contended the project is covered by the so-called Dover Amendment, a state law that allows schools to circumvent local zoning restrictions for education-related projects. Piper ruled the proposed light towers are not exempt from the town’s requirements for a site plan review and special permit for their installation.