Washington ( CNN ) -- U.S. Defense Department officials debated how to dispose of more than 1,000 fragments that could have included human remains from the September 11 attack on the Pentagon before they ended up in a Delaware landfill , according to newly released internal documents . The internal discussion about what to do with the `` biological '' material was released Friday as part of an investigation into the workings of the mortuary at Dover Air Force Base . In a 2002 e-mail discussion among Defense Department officials , one official identified in the redacted documents as a colonel suggests scattering the material at sea . `` I do like the idea of spreading the ashes at sea in that it is a neutral arena ; it should represent an area readily agreeable to all parties , '' the official wrote . A civilian official suggests that it might be appropriate to witness the scattering at sea and to have a chaplain present . Another official , however , expressed concern that an at-sea disposal might `` send a message to the next of kin that we are disposing human remains , and that is not the case . '' That official asked that the powder and ashes be disposed of `` immediately '' and as `` normal waste . '' The colonel responded by saying that disposal would be based on that guidance , but reminded the official that the material was not `` normal . '' `` My point , as you are aware of , is that Group F is not your normal set of medical waste , '' the colonel said . The material is referred to in the documents as `` Group F '' and `` special . '' Officials at the Pentagon explained that this group included material that was biological in nature , but it could not be determined that it was human or whether any terrorist remains were mixed in . `` That was at the heart of the debate first because we did not know whether these were human remains to begin with , '' said Jo Ann Rooney , acting under secretary of defense for personnel and readiness . `` We knew that they were biological , but they were mixed in with pieces from the building , from the airplane . '' Even something from someone 's lunch would show up as being biological in nature , according to Rooney , who said that the internal debate went on throughout the Defense Department and reached into very senior positions . Dover Port Mortuary has been engulfed in scandal since November , when it was discovered that some remains of deceased U.S. troops were discarded in landfills until 2008 .
NEW : Defense official : `` We did not know whether these were human remains to begin with '' Defense officials debated how to dispose of more than 1,000 fragments of material . The material was from the September 11 terrorist attacks on the Pentagon . The material was `` not your normal set of medical waste , '' a colonel says .