TribLIVE's Daily and Weekly email newsletters deliver the news you want and information you need, right to your inbox. Westmoreland County officials say more than 15,400 mail-in ballots have been sent out to voters ahead of the May 18 primary. Another batch of more than 800 ballots is ready to go out, Elections Bureau Director JoAnn Sebastiani said. The deadline to apply for mail-in ballots is May 11. They must be received at the courthouse by 8 p.m. May 18 to be counted. The county’s Elections Board on Wednesday approved the use of one additional drop box at the Westmoreland County Community College location on Mellon Road in Murrysville. That box will be open from 9 a.m. to 2 p.m. Saturday and May 15.