I got this information off of the global security website - All through the Vietnam War PACCOM was in charge of the logistics including the movement of tactical herbicide.
PACCOM was reorganized in 1972 at the end of the war. It gives the chain of command under the re-organization. 267th Chemical Command at Camp Carroll at the same time they had platoons or detachments on Johnston Island and in Okinawa during Operation Red Hat and Operation Chico in which the 267th was in charge. It also puts the these two operations involved the movement of all tactical herbicide to Johnston Island for final disposal by dumping at sea or incineration. This ties all three locations to gather with the 267th during these operations. And all three locations are know to be dump sites. Camp Carrol, Korea - Taegu Storage Unit