John, my preliminary research indicates that 29 crew members of the USS CHENANGO died from the effects of the explosion. I have perused three different sources for this information, namely the deck log of the CHENANGO, General Order No. 38, and the weekly lists of deaths in the Union Navy, as published in the pages of the [Washington, D.C.] newspaper, the DAILY NATIONAL INTELLIGENCER. Another crew member died after the publication of GO 38, so is not listed in that source.