Wes Slate, vice president of the Beverly City Council, has announced plans to run for mayor of Beverly. Slate, 63, grew up in New London, Conn., and holds a bachelor’s degree from the University of Connecticut and a master’s from Wesleyan University. Slate has lived in Beverly since 1982, and has served on the City Council for the last six years. He is the third candidate to join the mayoral race since Mayor William Scanlon announced he would not run for another term. In addition to Slate, Mike Cahill and Euplio Marciano are also running for mayor. If elected, Slate said the two biggest projects he would work on would be the proposed renovation/rebuilding of the Memorial Middle School and the reconstruction of the Brimbal Avenue interchange on Route 128.