The following information was extracted from the book `United and Undaunted’ by Ross Blue. The book is a complete history of the RAN Clearance Diving Branch and Ross was the CO of one of the Teams that served in Vietnam.
Clearance Diving Team 3 was formed in late 1966 comprising one officer and five sailors and after passing through a rigorous refresher programme in EOD, small arms and Army jungle training at Canungra they landed in Saigon in February, 1967.
At this time the Free World Forces acting in support of the SVN Government had experienced continuing and increasing losses from enemy forces skilled in guerilla warfare, in particular the teams of sappers and swimmers who specialised in clandestine operations against riverine traffic, harbour anchorages and areas of high population density. To counter these units the USN had established a network of Harbour Entrance Control Posts along the coastline of SVN and manned them with patrol forces and supporting EOD Teams. This operation was known as `Stable Door’ and it complemented the seaward Operation Market Time which aimed to prevent the illegal entry of munitions.
The Team was initially employed near Saigon with the local EOD unit to settle in and undergo ‘in country’ indoctrination courses. At the end of February they were despatched to Vung Tau where they set up their HECP atop Nui Lon mountain or VC Hill as it became known. From this vantage point the harbour from Vung Tau to Long Son island could be observed. The basic accommodation was an old gun emplacement and bunkers built by the French in bygone days. They were bare but solid and over the three years that the Teams operated out of them they were progressively developed until it had become famous for their comparatively luxurious appointments.
The Team’s primary task involved the checking of shipping in the anchorage for swimmer laid mines and secondly, as the Team was the only EOD Team in Phouc Tuy province, reacting to calls for EOD assistance from any allied authority.
Shipping checks were carried out from the Team boat at periods of favourable tide and sea state. In the open anchorage, fed by the Saigon River, tidal streams often reached 6 knots which, combined with monsoon wind and rains, made the area a difficult place to work.
When not working in the harbour, the Team ranged wide in Phouc Tuy, clearing booby traps, disposing of damaged ordnance at Vung Tau airfield and the local military bases, providing demolition support for allied forces, and diving to recover weapons, equipment, downed aircraft and human casualties.
In August the first Team returned to Australia and shortly thereafter the US Government announced the award of Meritorious Unit Commendation for CDT3 in recognition of their most professional work in such hazardous conditions.
The second Team were soon hard at work and late in August they suffered the first CD casualty when a member was wounded by a sniper during an opposed amphibious insertion north of Vung Tau.
In October CDT3 was officially designated an EOD Mobile Unit (Pacific) and its responsibility was widened to include a part of the Mekong Delta. This change was brought about by the fact that CDT3 comprised 6 men compared to 3 borne in USN EOD Teams.
During the year an impressive array of ordnance was rendered inert and displayed for training purposes. The work was dangerous as one Team member found when a fuze exploded in his hand – fortunately the wound was slight.
January 1968 brought the first Tet offensive and although no major increase in activity occurred in Vung Tau, security was tightened. The Cat Lo Naval Base was rocketed from Long Son Island across the Bay.
The third Team took over in March 1968. Shipping movements were down numerically after Tet but EOD calls and riverine operations increased. The Team took part in Coastguard action against a gun running trawler which resulted in the destruction by detonation of the latter after accurate 5″ gun fire from the Cutter.
In April, Vung Tau was again rocketed from Long Son and the team was required to clean up the remains. Dud fired rockets were added to the training collection.