find leak, convert to water or repipe returns

tim smith

Got a 33 unit condo, underground steam returns leaking. Board has known about this for 5 months at least and just now getting closer to decision. We could have leak detection company come in and try and locate source(s) of leaks. Also boiler is shot. Boiler to be replaced, still pending decision. We could repipe floors above basement with overhead returns at ceiling of basement and then maybe do a steam to water heat x and to a hot water zone for basement units. Or, which i am ?? of. They are talking about repipe all the returns in bldg and convert to water, but that still leaves possible leaky steam mains now that water would be in them. Looking for what you all think, really can't repipe underground as the finished basement units are occupied. Any input appreciated all. Tim