On Friday, Dec 17, maintenance tasks needed to be done. Fuel filters were replaced on the big generator (70 kva). That’s what is powering the pump at the dam, since the grid is not powerful enough. The other generator (10 kva) was also tested. A new pump, kindly loaned by a dealer, was delivered to the site. This one is much more powerful, approximately 25 cubic meters per hour, in comparison with 12 currently. All electric adaptations for this new equipment were worked on during the day, and the installation will be done on Saturday. This added efficiency will allow to again pump Sump 2 and continue to work downstream of it.
Since it is not possible to dive Sump 3, there is one chance left to continue onward: through a passage 50 feet up above the sump. To do this, Sump 2 will need to be emptied, and a team of cavers will need to be able to cross it safely. In order to do that, the following must be accomplished:
1. Enlarging Sump 2
2. Installing a sump pump in Sump 2 while repositioning the discharge tube that connects Sump 2 to Sump 3.
3. Installing a large-diameter tube to divert the main stream directly from the dam into Sump 3, so that Sump 2 will not be fed by the stream anymore.
Of course, these goals will be affected by the weather of the next few days.
On Friday evening, a very motivated team was going to bring the electric motor of the pump down to the dam. This load, weighing more than 175 pounds, would be transported the same way as the first pump: in a rescue litter. But before the transport occurred, a template of the body of the pump was created and brought down. At every corner where it would not fit, diggers enlarged the passage. This operation lasted a large part of the night. Another team took apart the first pump, which will be kept as a back up near the new one.
On Saturday, Dec 18, the real pump, which measures over 7.8 feet long, was carried into the Puits de Ronze. The transport worked relatively smoothly until Sump 1 was reached. Since a tight corner had not yet been enlarged the night before, more widening had to be done to accommodate the length of the pump body.
Towards the beginning of the afternoon, the pump had arrived near the dam. All sorts of tasks, including modifying the control panel, were then necessary for installation, and those tasks lasted a few hours. Then the discharge tube and the power cable had to be connected. Finally, towards evening, after a series of tests, the pump was operational.
The plan for the night crew was as follows: empty Sump 2 into the dam; once empty, enlarge the sump by using explosives, until it is easy to cross; reposition the tube between Sumps 2 and 3; divert the main stream directly from the dam into Sump 3. If all that can be accomplished during the night, then the bolt climb can be done on Sunday…
On Sunday Dec 19, the entire pumping system was functioning. The new pump in the dam was bringing out the water to the surface, and the dam was not overflowing anymore. The water from Sumps 1 and 2 were being pumped into the dam. Some fine tuning even improved the debit. Sump 2 was empty by end of morning. The diggers were able to open up the narrow part of the sump. However, the configuration of the sumps had slightly changed. The ubiquitous sand in this flooded passage had moved and had partially clogged the passage that was open just a few days previously. And so it was necessary to again start removing sand, bucket by bucket. After a few hours, the passage was again open and the way was free to reach Sump 3.
The tube was repositioned into Sump 3 and finally, the terminal sump was absorbing all the water sent into it. The safety of cavers beyond Sump 2 is now ensured, and the climb above Sump 3 can start. The climbers started bolting up the wall while another team installed the diversion tube between the main stream and Sump 3. Yet another team did a dye-trace of the stream at the level of Sump 3, and surveyed the new part of the cave.
By the end of Sunday, the climbers had reached more than 33 feet up a chimney. They entered a meander and about 50 feet later were stopped by a piece of breakdown that needed to be removed. Behind it, they could see the passage continuing. In the chimney, 16 feet higher than the start of the meander, the climbers also saw an enlarged area that could be the start of a new passage. However, they had run out of bolting equipment. In spite of all the efforts expended on this weekend, it is still not known if it’s possible to access the flooded area of the Dragonnière. One thing is for certain: the chances are diminishing rapidly.
In order to allow all the participants to spend Christmas with their families, it was decided to stop all work for three days between December 24 and 26, no matter what the results of the climb will be.
(There are two more updates, for Monday and Tuesday, which I will translate later. Short version: the way on is still being worked on, and a passage with good air was found. The weather interfered, and the teams had to get back out.)