On the recordJune 23, 2003
the latest is that reports are now circulating that instead of being used for biological or chemical laboratories, these two trucks were used to make hydrogen for the purpose of filling up the Iraqi weather balloons needed by Iraqi artillery and used by all artilleries to gauge wind and currents and so forth to make their artillery shooting accurate. It appears that the loose canvas covering on these trucks would not be conducive to their use as chemical or biological laboratories and that the equipment there is probably designed for hydrogen production.
Source
govinfo.gov
