RICHMOND, Ky. (AP) _ A storage facility holding TNT at the Blue Grass Army Depot exploded, setting off a small fire and ripping the bunker apart.

There were no injuries and obsolete nerve gas rockets stored at the base were not damaged in the explosion Thursday night, said Col. Robert A. Goodwin, the base commander.

The cause of the 7:05 p.m. blast was unknown. Three Army ordnance specialists from Fort Knox were to examine the above-ground bunker today, according to Lt. Col. Max Williams, deputy commander.

Another bunker containing conventional weapons about 385 feet away was not damaged by the blast. The closest bunker holding nerve gas was 2.4 miles south of the blast site, Goodwin said.

An unknown number of TNT charges and other detonators were stored in the bunker, Goodwin said.

The Army notified Madison County Civil Defense, Richmond police and state police to avert concern that the chemical weapons might have been involved, Goodwin said.

''We wanted people to know it was not chemical related. That was the thing we wanted to squash as soon as possible,'' Goodwin said.

No evacuation took place because chemical weapons were not involved, said Madison County Civil Defense coordinator Howard Colyer.

Nearly 70,000 nerve gas rockets, some of them leaking, are stored at the depot.

The Army has proposed building an incinerator there to dispose of the World War II-vintage rockets.

Some area residents have opposed such a plan, saying it could be hazardous. Others have opposed a proposal to move the rockets to another site for disposal.