Rescue of Trapped Cavers at Bungonia

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ANDREW BAKER and MICHAEL FRASER NSW Cave Rescue Squad Inc. | On Monday 17th February 2014 three missing cavers were rescued from a flooded passage in Bungonia Caves, south of Sydney.

This is an overview of the NSW Cave Rescue Squad’s involvement in the rescue and notes lessons learned.

Just prior to midnight on 16th February 2014, members of the NSW Cave Rescue Squad (CRS) were made aware of a possible callout involving a search for a small group of cavers who were reported overdue in Bungonia Caves.

An hour later a CRS first response team, consisting of seven CRS personnel, was dispatched in response to a request for assistance from the Goulburn Police Rescue Squad (PRS).

Initial details of the incident were scarce, with reports of a group of three cavers overdue in the well-known Fossil Cave-Hogans Hole cave system, B4-5, possibly as a result of flooding.

A fourth member of the group, who remained above ground as the emergency contact person, reported a large volume of water flowing in the B5 entrance.

Goulburn PRS had established a command post and performed a preliminary search of the popular route through the cave prior to CRS arrival.

First on the scene

Three of the first CRS members on the scene were then tasked with conducting a thorough search of B4-5 to rule out any possibility that the missing group were in this section of the cave.

During this search, three cave packs were located in Junction Chamber near the start of the B4-5 Extension, which was completely filled with water, indicating the missing group had probably entered the B4-5 Extension.

Meanwhile, a second team consisting of two CRS personnel and two Special Casualty Access Team (SCAT) paramedics entered Flying Fortress Cave (B17), a cave that has a locked gate and restricted access due to its scientific significance.

B17 provides downstream access in the B4-5 Extension with rescuers aiming to head upstream in the Extension, with the expectation of locating the missing group. Adjacent to B17 is Shaduf Cave (B15); however there is no access to the B4-5 Extension via this cave due to the unstable nature of the entrance series.

Blocked by sump

As planned prior to entering the cave, one SCAT paramedic on the rescue team waited at the junction of B17 and the B4-5 Extension, with the remaining three of the rescue team making their way upstream in the B4-5 Extension.

This section of the cave is relatively small and requires an extensive amount of crawling on one’s stomach. Unfortunately, after a considerable effort, progress was blocked by a sump and the rescuers were forced to turn back.

On returning to the B17 junction, they were met by a third CRS team, some of whom had conducted the earlier search of B4-5.

This third team had begun the process of setting up the Michie phone (a single wire communications system) by running a wire down B17 to the B4-5 Extension junction to keep the surface command informed of the situation.

A chilling thought

News of the sump complicated the rescue effort substantially as there was now a very real possibility (as turned out to be the case) that the missing cavers were trapped in a flooded section of cave.

This was a chilling thought and everyone hoped they were in an air pocket with sufficient air supply.

A further implication was the realisation that this rescue could take days to complete, so one of the SCAT paramedics exited the cave to organise additional paramedic resources.

Above ground, the CRS surface coordinator advised the PRS command post of the possibility that using cave divers might be the only way of locating the missing cavers.

As a result, four highly skilled and experienced cave divers were notified and immediately made their way to Bungonia. Additional resources were also sought from other squads within the NSW Volunteer Rescue Association (VRA), with members of the Bushwalkers Wilderness Rescue Squad (BWRS) called to attend.

Downstream rescue

In consultation with members of the team who had seen the flooded passage in Junction Chamber, the CRS underground controller determined that rescue from the downstream side of the B4-5 Extension was more feasible than from the upstream (Junction Chamber) side.

Accordingly, two CRS personnel extended the Michie phone wire from B17 up the B4-5 Extension to the upstream sump, in preparation for either lowering the water level using pumps or siphons, or using cave divers.

Meanwhile, another team of two CRS personnel performed a search from the B17 junction downstream into the B4-5 Extension in the unlikely event that the missing group would be located further downstream.

Upon completion of laying the Michie phone wire to the upstream sump, the two CRS personnel enlarged the natural drainage line, using rocks and their hands to dig a deeper channel.

This quickly started a reasonable flow of water out of the sump and down the formerly dry streambed. As the water continued to flow, other rescuers assisted in the effort to channel the water further downstream.

By this stage the majority of the rescue team had been up all night, followed by considerable effort underground for at least four hours.

Since the missing cavers had not yet been located, Goulburn PRS surface command requested all personnel, with the exception of the Michie phone operators, to exit the cave for a break and to reassess the situation.

However, by this stage the upstream sump was now a passable ‘roof sniff’, and given the best time to get wet and cold is just before exiting the cave, the two CRS personnel at the upstream sump proposed and were given permission to conduct a quick reconnaissance beyond the sump prior to exiting.

In the meantime, two other CRS rescuers moved upstream to man the Michie phone and ensure the outflow from the sump remained open.

After passing the sump, the two CRS reconnaissance personnel crawled along the stream passage until a much larger sump was encountered.

This situation appeared grim, but then suddenly, and much to their relief, voice contact with the missing group was established.

They confirmed that all three members of the missing group were present, uninjured, dry and relatively warm in Coffin Chamber, but trapped by flooded passage either side of them.

This message was relayed back to the Michie phone operator, who then notified the surface.

In the space of a few minutes everything had changed.

The search was now over and the exact situation was known. The focus could now shift to the actual rescue and the more immediate challenge of draining a much larger sump.

Fortunately, although a lot more effort was required to dig through the considerable gravel bank that was holding back the water, the gradient was steeper, and ultimately a much higher flow could be achieved here than at the first sump. In many places, access was very tight and awkward.

This required pushing the gravel on the floor to one side, then squeezing themselves into the channel until firmly wedged, then digging to allow water to drain out of the sump.

Initial attempts to ‘roof sniff’ through the sump were unsuccessful due to insufficient air space, but eventually, and with considerable digging, shivering and patiently waiting for the water level to drop, one CRS rescuer was able to negotiate the sump and reach the missing party.

After being provided with a soggy muesli bar each, the relieved missing party were rather keen to exit and crossed the now somewhat smaller sump successfully.

The CRS rescue team continued to escort the group through the second sump and along the long, and now very wet, crawl back down the B4-5 Extension to the B17 junction.

Two SCAT personnel were staged at the B17 junction and kindly provided everyone with large quantities of chocolate and lollies. It was around this time that the cave divers arrived on scene to the news that the cavers had been found safe and well.

Rescuers facilitated the ascent of three cavers up the short pitch in B17 by way of an assisted prusik.

Each of the three cavers prusiked up the access line but were also clipped to a counter balance haul line to assist their ascent. This dramatically increased the efficiency of ascent, given they were using unfamiliar gear and were fatigued, having been underground for more than a day.

Finally, they emerged from the cave and were reunited with their eagerly awaiting families.


Lessons learned

Reports of the situation were widely broadcast on news and media, with the rescued party widely praised for their experience and actions. This included their basic actions of devising an effective emergency action plan and appointing a reliable person on the surface.

Furthermore, they retreated to a safe place within the cave when it unexpectedly flooded.

While waiting, the group huddled to stay warm and conserved resources such as the batteries for their lights, which meant that later on they were in a position to exit the cave ‘under their own steam’, making for a much simpler, quicker and easier rescue.

Moving a stretcher-bound casualty along the low crawls of the B4-5 Extension would have been an incredibly difficult, strenuous and slow task, which thankfully was not required.

Throughout the operation, CRS members displayed a high degree of professionalism in their conduct. This included the way they worked as a team and with other agencies.

It is a credit to the effort and dedication that has gone into the squad’s training in recent years. In this respect, turning up to the scene and being greeted by familiar faces in other agencies that have participated in CRS training exercises, was invaluable for establishing great rapport and effective working relationships both under and above ground.

CRS wishes to acknowledge the invaluable multi agency collaborations, in particular Goulburn Police Rescue Squad and the Ambulance Service of NSW, which enabled the successful search and rescue of the three missing cavers at Bungonia.

For more information on the NSW Cave Rescue Squad, please email the secretary or visit Cave Rescue web site.