By Ron Smith, Kentucky Public RadioWorkers at the Bluegrass Army Depot near Richmond are searching for the source of a mustard gas leak.Monitoring personnel Tuesday detected trace amounts of the vapor inside a concrete igloo that houses mustard gas. Once the leaking munition is located, Depot spokesman Dick Sloan says they’ll follow a time-tested procedure.“When we find it, we pack it in a leakproof container and it goes into a special igloo that only has mustard leakers in it," he said. “Unfortunately, with vapor leaks there’s not a puddle or anything to tip you off to where it is, so then we have to isolate all of the rounds in there and by process of elimination try to figure out which pallet has the leaking munition,” said Sloan.It’s a process that’s been undertaken 144 times at the Depot over the past 27 years. But Sloan insists the response is not considered routine.“I would never say that. A leaking chemical weapon is never routine no matter how many times you’ve done it. The fact that we do have that long history of it tells me that the toxic chemical workers are well practiced in how to take care of it, but we don’t consider anything in that stockpile to be routine,” said Sloan.Chemical weapons have been stored at Bluegrass since 1944. So Sloan wouldn’t be surprised if more leakers show up. In his words, “Unlike wine and women, explosives and chemical agent do not get better with age.”