Cave diving rescue in France

[yvonnedroms]

By Friday evening, rain had started, and by Saturday Nov 20, 1.4 inches of rain had fallen. The temporary stream in front of the command center was running. Access into the Puits de Ronze was prohibited. The cavers on site occupied themselves with digging at the insurgence. A tarp was set up over the dig site to protect from the rain, and the stream was diverted away from the entrance. Others on site spent the day organizing for the pumping of Sump 2 this coming week.

On Sunday Nov 21, the weather got better, and it rained very little. One team continued their work at the insurgence. Another team went into the Puits de Ronze to continue the digging efforts in the Bousier. A third team went to change the rigging in the 45-meter pit. By the end of the day, the insurgence dig was over 20 feet deep. The fissure is widening, and the continuation seems more evident. A number of shots are still needed in order to continue, but the way on seems clearer.

In the Bousier passage, the diggers progressed by a few meters, but were stopped at a narrow constriction. Through it, they could see a wider area with a puddle of water. The last team of the day was tasked with inserting a pole, equipped with a camera, through the fissure to try to see ahead. The camera revealed a larger passage towards the right, and some concretions. This info is very interesting and of course quite motivating for the next crews.

-Yvonne

[yvonnedroms]

On Monday Nov 22, work continued at the insurgence on the surface, and in the Bousier passage in the Puits de Ronze. On Sunday evening, the camera at the end of the pole showed that a larger passage lay ahead, so a team went down on Monday to continue opening up the passage. After three shots, it was possible to progress by a few meters. Unfortunately, the passage turned out to be a chimney, without any visible lead. On Tuesday, it will be checked again for a second opinion. If that is true, though, one of the main ways on towards the objective will have been eliminated.

At the insurgence, digging continued all day long. The fissure continues downwards. Hopefully a larger void will be found soon.

The organization of the pumping operation in Sump 2 is going well. Suppliers of pumping equipment were approached, and hoses, cables, accessories, and electric pannels were secured. All that equipment will arrive starting Wednesday, and its installation will begin then. The pump, which was specially built in Italy for this operation, will travel on Wednesday and Thursday towards Nice, then to Labastide de Virac. If all goes well, and the weather cooperates, it can be installed on Friday and pumping can begin on Saturday morning.

In anticipation of the missions of this coming weekend, more people will be needed on site. Regional caving groups can also start planning extra teams for the following two weeks, until Dec 12.

[yvonnedroms]

On Tuesday Nov 23, one team continued digging in the insurgence, following a strata joint. It looks good for finding a significant void soon. At the Puits de Ronze, a team went to retrieve the sensors that had been placed at Sump 2. Those values will allow to fine tune what's known on the hydraulic system in the cave. On the way out, this team had two missions. The first was to identify all the passages that would cause problems for the installation of the tubing for the pump, and the electric cable. These passages were flagged for being widened. The second mission was to verify that the Bousier passage is indeed not viable and that work should be stopped there.

On the surface, it was hard work. The tubing for the pump was delivered. There is about 1000 feet of it. The hardest part is to roll it out and to tension it, in order to straighten out the plastic. It’s imperative to do that before it goes down into the cave. Normally, this is done in a warm setting, but that was not the case on this day. Hopefully the tension will be sufficient for the tubing to be usable.

-Yvonne

[yvonnedroms]

On Wednesday, November 24, a team went down to the tight passage at -75 m in the Puits de Ronze in order to enlarge it so that the extra equipment that needs to be installed through there will have room. It was a delicate operation since the enlargement shots had to avoid harming the existing cables and sheath passing through there. By the end of the day, that had been accomplished, making that passage much more comfortable.

At the insurgence, enlarging continues and slowly the little hole is becoming bigger. The fissure is now 23 feet deep. At the end of the day, the digging crew was standing on a solid floor with two small passages continuing, one in each direction. A void is felt below, but how far is it?

At the surface, procuring the pumping equipment is continuing. The trailer with all the electrical equipment and accessories arrived in the afternoon. The pump, made in Italy, is finished and is being readied for transport. It will leave on Friday morning, cross the Maritime Alps, and it should arrive at the Puits de Ronze by evening on Friday.

-Yvonne
P.S. Great pictures of the long pieces of tubing being stretched out under tension on the dirt road on the plateau, at the Spéléo Secours site:
http://www.speleo-secours-francais.com/ ... Itemid=182
I’m still amazed at the amount of hard work and free labor donated towards retrieving Eric’s body and returning him to his family. Every day, many teams of qualified cavers take days off to come from all regions of France to help with this effort. Awesome solidarity, persistence and determination! My hat is off to the French cavers.

[yvonnedroms]

Thursday November 25 was an important day for the pumping operation. The high-pressure plastic tubing had to be brought down into the Puits de Ronze. The black plastic snake was very stiff and the outside temperature was not helping to make it more malleable. A team of seven cavers started down with a first length of tubing. The technique needed was the same as for rescues: braking techniques, good coordination amongst the team members and good communication. Bringing this first piece down all the way to the lake took over five hours. Finally, at the last turn in the passage, the tube could not make the turn. A prefabricated elbow will need to be installed since the tube is not flexible enough to pass through the tight curve.

The team returned to the surface for a well-deserved lunch then started bringing down the second piece. This work lasted until the evening. Friday will be a very long and hard day, since the rest of the tubing as well as cables, fittings and pump control panels will need to be delivered to the bottom of the cave.

At the surface, work continued at the insurgence. Small passages are going off horizontally now. Widening continues, and the teams persist to see what this entrance will offer.

The pump has arrived in the Alpes-Maritimes and is on its way to the Ardèche.

The firm Béal was thanked for supplying rope for the rigging of the cave.

[yvonnedroms]

On Friday Nov 26, a command post for the pumping operation was set up at the Puits de Ronze. The pump arrived on Thursday eve. All day Friday, plumbers, electricians, engineers worked at the surface to test and outfit the pump. The 380 volt power line was assembled at the surface and will be taken into the cave as one piece. A special telephone line dedicated to the pumping will also be installed at the same time as the power cable.

Work continued inside the cave as well. The pieces of tubing were taken down and connected together. The last junction is in the entrance pit. On Saturday, the tubing will be connected to the outside and extended away from the entrance.

Saturday will be a decisive day for the pumping operation. If all goes as planned, by end of the evening the pump will be in place and connected to the tubing, and the first tests will be done. Pumping could start that evening or at the latest on Sunday morning.

-Yvonne

[yvonnedroms]

On Saturday November 27, the pump was taken down in two pieces. The motor, sheathed for protection, was placed into a rescue stretcher, together with its electric connection box and a length of cable. Packaging this fragile but heaviest part of the pump (150 pounds not counting the weight of the stretcher) in that manner made it easier to transport, and risks of shock were minimized. The body of the pump, only 66 pounds, was placed into a sheath and lowered down just like the stretcher by using rescue safety techniques. Slowly the two packages made their way down the pits and through the narrow passages. It took a lot of effort to pass through the problematic sections, but all difficulties and obstacles were overcome, and the special convoys arrived at the dam unscathed.

After that, a new human chain was created at the entrance of the Puits de Ronze. Over 30 cavers were positioned in strategic places in the cave to help snake the 1000-foot-long aluminum cable (4x25²) in one piece all the way down to the dam at -140 m depth (-450 feet). The cable was marked every 60 feet to help the team members position it at the right locations in the cave. The special telephone wire (Océane) was also brought down as far as the pump.

Towards the end of the afternoon, a team tasked with the final set up of the pump and its electrical connections went underground. Their mission lasted about 8 hours. The pump was started for the first time just before midnight. After some testing it was operational and the water started gushing outside. The last team exited the cave.

Another team was at the resurgence to continue widening there. The way on is now more evident. Water is flowing down a small fissure, but the work ahead still seems hard.

-Yvonne

[yvonnedroms]

After a very intense Saturday full of preparations, it was time to start pumping. On Sunday Nov 28, the morning was spent tightening the connections to make them more waterproof and finishing the routing of all cables and tubing. One team checked the pump’s automatic start. By the end of the afternoon, everything was ready and water gushed out again on the plateau. All the pumps were operating. The pump at Sump 1 delivers water to the dam. (So will the extra pump in case of emergency.) The pump in Sump 2 also delivers its water to the dam. The dam’s water then gets pumped to the surface. It worked fine in principle, but all too soon, it was noticed that the water intake was larger than what could be pumped out, and so the level of the dam rose and overflowed. For about 3 hours, the seals were improved and the debits were calculated. It was evident that there was much more water underground than the previous day, even though it had not rained. After some thought, the conclusion was that it could have been the weather, which had been below freezing for a few days. The water had frozen in the upper layers, then melted when the temperature went up on Saturday. Finally towards the end of Sunday, the debit diminished and returned to the normal 2 liters per second. At last, the level of Sump 2 started going down. After about 1.5 hours of pumping, it went down by 32 inches. But by then, the team had been underground for too long, and needed to come out. Everyone is optimistic. If nature will allow it, it will be possible to remove the sand from Sump 2!

[FW]

Yvonne, thank you for keeping us informed.

[yvonnedroms]

On Monday morning, Nov 29, a small team went down to the bottom of the Puits de Ronze to check on the pumps, to position the phones, and to rearrange a few tubes before starting to pump Sump 2. They arrived at the dam, which was overflowing. After some rearranging, the team started the pump and water again flowed up to the surface. The level of the water at the dam went down, then stabilized with the influx of the water from Sump 1. The team then headed to Sump 2 to start the pump there. All seemed well, and the level at the dam remained stable after both sumps were flowing into it. At Sump 2, the water level slowly went down, and the team was able to start digging out the sand from the sump. Bucket after bucket, large bags were filled. After digging down to -48 inches, the team was still digging out sediment and sand. Unfortunately, nature was still not cooperating. The floor in front of the sump is made of flowstone, and it’s undermined by sediments. The vacuum created by the removal of the water was taking those sediments towards the intake of the pump. Therefore that area also needed to be cleared. By the end of the day, more than 2 cubic meters or 4.4 US tons (4000 kg) of sand, water and sediments had been removed from Sump 2. The level of the sump had been lowered by about 5 feet. The results of Monday’s work were very motivating. Maybe on Tuesday, Sump 2 will reveal its secret.

-Yvonne

(I edited the ton figure)

[jharman2]

This effort is nothing short of phenomenal. Please keep up the posts Vonny!

[yvonnedroms]

If you'd like to get a feel for what the Puits de Ronze looks like at Sump 1, Sump 2 or at the dam, check out the photos and short video clips posted on Sunday Nov 28 on this French site:
http://mascdu26.blogspot.com/
Amazing how much stuff goes through those narrow passages. Ventilation hose, electrical cables, telephone and video cables, tubing for the pumps, etc. etc. In order to pass through the constantly emptied Sump 1, you have to crawl over all those lines... Incredible work. I'm so hopeful that soon the teams will be able to emerge in the Dragonniere, where Eric is patiently waiting to be returned to his family.
-Yvonne

[PYoungbaer]

This is such an incredible undertaking. My helmet's off to the commitment of these cavers/rescuers. Thank you for this stream of posts, Vonny.

[yvonnedroms]

On Tuesday November 30, various issues slowed down the operation. The 1-cubic-meter woven Big-Bag bags used at the bottom to store the sand and sediments are causing problems. The bags are not stiff enough and are too waterproof, and therefore they fold up and tend to lie down on their sides, and once that happens they can’t be straightened out because of the weight. So the first order of business was to go buy different bags. Finally at the beginning of the afternoon, the team headed down. They were carrying a different pump for Sump 2, which meant using another 100 meters of electric cable to connect it to the electric panel, and rearranging the tubing from one pump to the other. Another setback was that the pump in the dam stopped working. It took over an hour to finally realize that the problem was in the electric panel: under the tarp protecting the panel from the drips, the emergency-stop lever is not very visible, but it had been depressed by mistake while installing the new pump...

Finally all the pumps were functioning, and the water level dropped or stabilized. For hours, bucket by bucket, the sand was removed from Sump 2. It’s a struggle: the sediments stay glued to the bucket, and it’s almost harder to empty it than to fill it. And again, same as in previous days, the water started flowing faster because of the thawing of the surface water, and in addition, a hard rain had fallen on the plateau. The teams perseveres in removing the sand. At the end of their mission, they could see a good distance into the passage, about 17 feet, which is what the divers had seen previously. It’s not passable yet, but hope is growing for the next few days, if only the weather cooperates.

The Spéléo Secours Français thanks the maker of the Italian pump ITT LOWARA, as well as some of their personnel who took it upon themselves to respond to the urgent request.

-Yvonne

[yvonnedroms]

There is still no official report for Wednesday Dec 1 on the Spéléo Secours site, but I was able to glean some info from someone who is helping at the Puits de Ronze, who posted on a French forum, and so, unofficially, here is what's been happening. In the last couple of days, one major issue was that the sand was collecting in the tubes in the lower sections of the passages. So an idea was to cut the tube at the dam, and put in a T-junction with a tap that would allow to clean out the sand and make the pump more efficient.

On Thursday Dec 2, two of the pumps failed almost at the same time, and Sump 2 filled up again. Issue after issue came up after that. One pump started again, so pumping restarted in Sump 2, but after only a bit of digging was achieved, the pump got clogged with sand. That pump was traded for one from Sump 1, but the extension cord wasn't working. A bad plug got identified and fixed. Another pump was on its way down, but when it arrived, the plug did not match the extension cord. After taking apart the plug, the pump was connected and miracle, it worked. By then it was late and the team returned to the surface, ready to start work in earnest on Friday.

The plan for the next couple of days is to acquire another pump, 1.5 to 2 times more powerful, which will be used at the dam, and to use an electric dredging pump capable of sucking up the water/sand mixture at the rate of 30 cubic meters per hour, which was generously loaned to the operation. The T-junction will also be installed at the dam on Friday since no one got to it on Wednesday.

Other details: In every nook and cranny, at every level of the cave, huge bags filled with sediments and sand are piling up, sometimes covered with wire fencing to keep them in place, or bolted to the walls.

Again, this was a non-official account by one of the participants.

-Yvonne