Mitsui Chemicals issued the statement on April 22 that had some information about the depleted uranium catalyst stored at its petrochemical complex in Iwakuni City, Yamaguchi Prefecture:
Also, we store the spent catalysts that contain radioactive materials in the warehouse inside the plant complex in strict adherence to the related laws and regulations. The warehouse is about 500 meters away from where the accident started. The containers are intact, and the current levels of radiation is the same as before the accident.
Nippon Television News has a bit more details about the containers:
The spent catalysts containing radioactive materials were stored in the warehouse in double-walled containers made of stainless steel. Explosions at the complex broke window glass of the warehouse, but there was no unusual measurement in the vicinity of the warehouse.
Depleted uranium was used as catalysts in 1960s and 1970s.
Hardly anyone wants to believe the official (government, the guilty company, mass media) accounts these days, but the official accounts continue to say there has been no leak of toxic chemicals or depleted uranium.