Paper giant WestRock, formerly MeadWestvaco, unveiled final plans for the sprawling 72,000-acre East Edisto tract Thursday, saying 53,000 acres will be protected by the newly formed East Edisto Conservancy. Plans began nine years ago for the 19-mile stretch as landowners, community leaders and conservationist started to lay out a vision to develop portions of the rural tract and protect much of the rest as existing plantations, farmsteads and green space.