Cancord is proud to sponsor the US Deep Caving Team’s expedition of Cueva Cheve in Oaxaca, Mexico. Recently Bill Stone posted the following update on the expedition
On March 13 Marcin Gala and Phil Short cracked Sump 4 in J2. They had been underground for 15 days when the first exploration dive took place. Approximately 150 meters into the dive they had to repair a broken guide line laid by Jose Morales in 2009 but otherwise were able to use the 2009 dive line to the limit reached by Jose in the right hand tunnel at 300 meters penetration from dive base. There Phil Short led on laying a full 120 meter spool of Cortland dive line followed by 2/3 of a second spool before they were confronted with a travertine wall blocking the underwater tunnel. After some searching they discovered a small opening between a stalactite curtain that allowed them to get out of the water onto a travertine platform. They left their dive gear there and proceeded onward for 100 meters in a large air-filled tunnel which included travertine walls and large stalactites, and one significant swim that they did in their Santi drysuits. Ultimately they reached a large borehole tunnel where the river descended into a fractured vertical fissure. Lacking vertical gear they terminated the reconn effort there. The inbound swim had been 71 minutes in a very large tunnel (12 x 6 meters with crystal clear turquoise water with white sandy floor and no silt). The return dive was 40 minute continuous swimming. Phil Short estimated the length of the sump at 600 meters. We will post a more precise number when the survey data are processed. The maximum depth was 12 meters.
At the time of this report Marcin and Phil are scheduled to be transporting the Poseidon Mk6 rebreathers and carbon bailout tanks back to the downstream side of Sump 2 for a planned upstream return tomorrow mid-day. A team consisting of Nicholaus Vieira, Miko Harasimowicz, Sasha Deryuga, and Dmitry Kraev will meet them at the upstream side of Sump 2 for support back to Camp 3. We expect all parties out by this coming Sunday (March 17). Many, many others supported this dive with the hauling of equipment, food, rigging gear, and film gear over the past 5 weeks.
There will be a team meeting following the arrival of Phil and Marcin in basecamp that will center on the next steps to be taken in J2. The reconn did not locate a suitable site for Camp 5 and the length of the dive puts it beyond reasonable length for running a 9 mm haul line as we currently have installed in Sump 2 (which dramatically speeds transit and increases safety). We estimate 50 to 60 minute swim time with fins only and a large equipment bag. This range distance (600m) is currently at the hard limit of our sidemount bailout tanks so considerations will need to be made, possibly by staging bailout tanks down the length of the tunnel at 200 meter intervals. Considerations for a hanging (hammock) bivouack beyond Sump 4 will also be considered. We have the equipment to do this and will reach a strategy for moving forward within the next week.
Peripheral to the diving work, surface reconnaissance work up the upper Aguacate canyon by Pawel Skoworodko, Artur Novak, and David Rickel resulted in the discover of a karst capture zone approximately 1 kilometer west of the Last Bash entrance, in an area predicted to have a fault parallel to the J2 and Cheve faults. Reconn work in this area will be intensified over the next few weeks.
Meanwhile, a new shaft series has been discovered in Last Bash, leading off from the base of the first pitch. This was initially pushed by Mark Minton, Vonny Droms, Kasia Biernacka, Bill Stone, and Nico Escamilla. Today a fourth push is taking place with Matt Covington, Elliot Stahl, and David Rickel heading in with another 200 meters of rope to pick up at the -300 meter level. There is much conjecture as to where this is going. If it reconnects to the main shaft series then little is gained, but if it heads east and intersects the Jungle Series in J2 beyond the Surprise Sump, then it could result in a major fast new route to the lower levels. Currently all resupply operations are signficantly hampered due to the exceedingly tight constrictions between the -500 meter level bivouack on the Last Bash route and Camp 2A in J2.
We will post further clarifications as they become available. However, as of today the expedition is on track and on schedule and a major milestone accomplished with the cracking of Sump 4.
