BAGHDAD — The Pentagon is seeking to declassify strike targets in Mosul where American bombs did not explode, Defense Department officials say. That information would be used as part of a long and potentially dangerous effort to make the city, the site of eight months of fierce fighting between the Islamic State and an American-led coalition, livable again.

Lt. Gen. Stephen J. Townsend, the commander of the campaign against the Islamic State in Iraq and Syria, said Thursday that he was looking for a way to lift longstanding rules that keep secret, for 25 years, the exact coordinates of unexploded ordnance.

Humanitarian groups and ordnance removal specialists on the ground in West Mosul have reported that the city is littered with booby traps and improvised explosive devices left by Islamic State fighters, in addition to dozens, and possibly hundreds, of so-called dud bombs that were dropped by United States warplanes but never exploded.

“ISIS used the planting of I.E.D.s as literally a weapons system to make it as difficult as they could for Iraqis to return home,” said David T. Johnson, vice president for strategic development and Washington operations with Janus Global Operations, which works with the United States on ordnance removal. Islamic State fighters booby-trapped West Mosul “to a degree that people in our business have not seen before,” Mr. Johnson said in an interview.