Cave Diving, Cave Exploration and Cave Mapping in Yucatan, Mexico
A bathing bird at the Zoo in Sydney

Three More Trips to The Pit

Learning to lift an unconscious diver, confirming an alternate route to Jill’s Chamber and a DCS incident.

After a long brake it was time to go back.  This time we started different; with the success of the previous dives in mind we decided to go full scale this time. The main idea was to make the whole project as safe as possible. We quickly understood that being just the two of us would not cut it anymore. Analyzing scenarios including an unconscious diver, a growing number of tanks, and increasingly complex logistics led us to the fact that we would need more support, at least two more divers.

The search was difficult because we were looking for people who like to spend their days off carrying numerous tanks, being eaten by mosquito’s, spending hours out of the water just waiting to later jump in and shuttle tanks around. They also need to understand their role in the team and why we can’t have them fun dive or risk anything even remotely dangerous.  Plus, the idea of trusting your life with somebody else is quiet disturbing. With Hans continually supporting deeper and deeper we needed somebody to fill his spot and somebody out of the water. After many discussions, Hans and I finally called Alain Pocobelli and Etienne Rousseau.  After we explained the criteria for participation they were super stoked and happy to join…awesome.

We all met at Pro Tec for our first meeting.  We discussed protocols, procedures, and set some goals. Specifically, we developed an idea to build a system to lift an unconscious diver from the water up to the trucks, an emergency and evacuation plan, and the parameters for 5 progressive dives the last of which would be a push dive to the end of the line in the Next Generation Tunnel.  We also agreed to document our experiences, procedures and protocols in a manual.  The manual would be used to educate new team members, in the event of an emergency as well as guide our decisions.

The plan for the first day was to setup the unconscious diver system and dive to the Wakulla Room supported by Alain and Etienne. For the support divers, it would be their first opportunity to learn the descent lines and the start of the main line.  For Hans, it would be his first deep mixed gas cave dive.  I would use the opportunity to execute a practice bailout at 300ft while swimming a horizontal distance through the bypass; the primary objective was to confirm my numbers.

As with all complex plans it was bound to change. Constructing a system for lifting a 235lbs (106kilo) diver with equipment 20ft (6m) from the surface of the water and then swinging him on to a platform was more difficult then anticipated. We wanted the system to be simple enough that a single person could operate it in high stress conditions. With limited climbing gear and other resources it seemed almost impossible. Through trial and error it took us some 5 hours to construct and test a nearly working system.  I write, “Nearly” because it still required two people to operate.

After the enormous effort, Hans and I called our dive.  We were exhausted, stressed and it was late in the afternoon.   With the roles reversed, Hans and I played support and cleaned up while Alain and Etienne made a reconnaissance dive.

That evening, I left with a slight feeling of defeat.   It was the first time I went through the effort of blending, putting everything together, waking up early, paying the entrance fee and then not diving.

Three days later I was back at The Pit with a similar plan, this time with Hans and Chris.  Chris is a professional Cave Rescue Expert from Poland. He and I had been diving the week before and when I heard of his profession, I knew I had to get him out there and learn from him.  He quickly came up with 3 different lift systems. Unbelievable!  To our relief, he thought our system wasn’t bad at all; we were just missing one critical improvement that would facilitate single person operation and swinging the body onto the platform.

Unfortunately, rigging and testing took a lot of time and required considerable heavy lifting.  Just like the day before, we finished setting up late.  As I prepared for our dive, I contemplated calling the dive; however I wasn’t able to leave The Pit again without trying my suit inflation system, my new helmet and the bailout plan. Mistake #1.

It is funny how we can feel pressure where there is none. As we prepared for the dive we were feeling time pressure; therefore we decided to shorten the bottom time. Without my normal pre-dive meditation we hurried into the dive. I laid line and Hans staged his intermediate mix.

Cruising through the bacteria cloud at 190ft (57m) I was super happy to finally be back. At the T before the Bypass Hans and I split, he swam through the Bypass at 281ft (85m) and I took the deeper “Main Tunnel” at 305ft (93m). Surprisingly, it is quiet narrow and more difficult to pass.  Two minutes later we met at the second T where the lines join again; it was time to turn the dive and start the bailout drill.

I signaled Hans and bailed out. I chose a bailout gas with a deeper END than I normally use to make it more difficult and more realistic.  To add to the realism, we planned to exit the cave with haste to simulate the highest possible gas consumption due to stress or CO2 poisoning.  For precaution, Hans closely monitored me ready to donate a shallower END bailout gas or I could go back on the loop in the event the Inert Gas Narcosis was too strong.

The first three breathes brought on the strong narcotic effect and it became difficult to focus on my objectives. Complicating the situation was the fact that my weighting in saltwater was neutral with my wing totally deflated. So being off the loop with gas remaining in the counter lungs made buoyancy management more challenging.

Imagine me swimming at full speed while squeezing through the Bypass, switching the set point down to avoid O2 injection, opening the OPV and rolling to get as much gas out of the loop as possible and I was becoming positive, all under the effect of Inert Gas Narcosis…what a blast. I am happy I couldn’t see myself.

By the time I arrived at the turn at 213ft (65m) I had regained composure and everything went “pretty” smoothly from there.

The main goal of simulating a realistic bailout scenario at depth was absolutely accomplished, I learned A LOT.  The old saying: “Slow is smooth and smooth is fast” confirmed itself once more, thanks Steve. I use this line like a thousand times per course, maybe I should listen to myself once in a while.

After the dive, we truncated our normal 2 hour break because it was getting dark. As I climbed out to hoist and load the tanks, I felt a slight pain in my left shoulder and right ankle; it subsided quickly.  However, it was definitely an indication we worked too hard before and during the dive and that we needed more conservatism.

As we loaded the truck, I got a phone call from Alain who had taken off the next day to join us at The Pit. Since support was available and we agreed to not do anymore push dives without support, we felt obliged to dive.  We agreed to dive the next day, mistake #2.

Again, it is funny how we feel pressure where there is none.
We didn’t anticipate that our desire to increase safety by having more support onsite would pressure us into something we knew from the beginning was a bad idea?!?

After blending and prepping the rebreathers, I arrived home at about 2200h. I ate, hydrated and went to bed. The next day we started even earlier to hedge against time pressure. However, we left Playa late because we had to reassemble the CCRs, analyze gases and leak check everything in the pool. Once on site we reinstalled the evacuation system and instructed Alain on the improved version.

For a second day in a row, I was late into the water due to Hans calling his dive because of technical difficulties with his Meg and Alain bruising his leg when he slipped and trapped it between the platform and the rock wall.  Calling the dive crossed my mind, however everything was in place and I felt confident it was safe.  Once the dive started, I was slower then normal as I had to swim all my tanks and stage them.  Mistake #3.

My goal was to explore the other passage into Jill’s Chamber and see if it would be easier to navigate with a scooter then the horrible chimney I passed last time. I hoped to find the origin of the line that was paralleling the main line through Jill’s Chamber into the Next Generation Tunnel. To add conservatism, I selected the VPM B/E algorithm.  I wanted to accommodate for the back-to-back days of deep diving, the strenuous pre-dive work and as a response to the way I felt the day before.

I arrived at the end of Wakulla Room only a minute slower then planned, even though I had to stage all my tanks.  As I swam through the BMB, I started to get a little nervous again, anxious to see the size of the restriction.  Before the T, I crossed sides to get a peak up the restriction. Fortunately, it was a little bigger and did not ascend vertically like the chimney.  It’s slope was more manageable as it ascended to 328ft (100m), instead of 314ft (96m).  There it led to a canyon depicted cave, which headed towards Jill’s Chamber.

After a short distance there is another T. Well actually it is a Jump that is “T”ed into the main line. The main line ends about two body lengths after. So I took the T to the left and further ascended into an even narrower canyon, which further ascends towards Jill’s Chamber.

I was stoked because I was nearly 100% sure that I had found the origin of the paralleling line and passed the chimney. About 1 minute later I was in Jill’s chamber and it was confirmed. It is pretty hard for me to explain my emotions; I felt unbelievably awesome! I think it took me like 30sec to gain control over my euphoria. I was 20min into the dive and I had fulfilled my objectives; it was time to turn.

The way out was relaxed since I did not have to pass upside down through a tight restriction. My decompression obligation was substantial due to the more conservative VPM B/E algorithm. I stopped at every waypoint to keep track of exit times, picked up the tanks and did a couple of short deco stops in between the levels.  Forty-five minutes into the dive I could see the open water in the distance and my Time to Surface was about 160min.

At 131ft (40m) Alain greeted me, took my tanks and left me with one 80cf.  I swam around the huge dome to stay warm and to help the time pass a little bit faster. Even though I was warmer then past dives, I decided that this would be my last long dive at The Pit without a habitat.

When I arrived at 40ft (12m) the dive had been going perfectly and I was very happy.  I swam around and moved my upper body a little bit to warm up and increase blood flow. Suddenly, I felt an unbelievably sharp pain in my left shoulder. At first I was shocked but I was hopeful because I still had almost 2 hours of deco ahead. The pain faded about 15 minutes later; however, I decided to extend all the remaining stops.

When I arrived at 20ft (6m) I extend my 65min stop to 75min. The pain was almost completely gone and I started to surface. At 10ft (3m) I added a stop even though the urge to surface after 4h almost drove me crazy. After 5 min I started a super slow final ascent. Almost immediately upon surfacing the pain in my shoulder returned at full intensity accompanied by pain in both ankles.

I stayed in the water on the loop breathing O2 for 20min contemplating what I should do.  Should I get out of the water or go back down?  Eventually, I decided against going back down because of my body temperature, general physical state and a 100%+ CNS clock.

As soon as I surfaced and didn’t come off the loop, Hans was nearby with an 80cf of O2.  When I decided to exit the water, he helped me strip my gear and I pulled myself up onto the wooden platform. I lay there breathing open circuit O2, hydrating and scanning my body for neurological symptoms. After 30min the intensity of the pain hadn’t changed. I decided it was time to evacuate. I climbed up to the trucks and sat down for a moment.   The pain disappeared and the general fatigue vanished.  Coming off the long period of high PO2 it seemed plausible, but I didn’t trust the situation since something felt strange.

As we left The Pit, I continued to scan myself for pain or neurological symptoms related to DCS. I felt great and honestly a bit relieved. The entire drive back I tried to figure out what happened.  I wanted an explanation for the weird sensations I had at 40ft (12m), on my final ascent and shortly after the dive. Why did I feel that way and what can I do different next time?  Arriving home I felt unchanged: no pain, no extreme fatigue, and no other symptoms. A long day had passed and I was happy to be home and ready for dinner and bed.

I am really happy about our progress and our understanding of the cave.  I am also happy that our team is growing and we are taking a more conservative approach to diving and the project’s logistics.  The project is remains very exciting and we are learning so much from each dive.

Looking back it is easy to identify many of the mistakes.  Many of you will ask why I made them? I can only answer that I am human, this is a learning experience and mistakes are inevitable.  Sometimes the cost for a mistake is small, sometimes it is huge.  Life it seems is a hard teacher, many times you get the test first and the lesson later. There was a time when I read articles like this and said: “Ha, I would never make mistakes like that.” But this was also a time when I didn’t do dives like this.

I want to thank Chris for his invaluable input on our rescue system, Alain and Etienne for supporting us and joining the team and Hans for letting me post on his blog.

Unfortunately, as you may have guessed, I suffered a DCS incident.  I am going to follow this story up with another about the DCS.

This is my story about the Pit and it is to be continued.

Edited By Hans

7 comments

1 Steve Bogaerts { 11.06.08 at 2:20 am }

Hi Patrick,
I have great respect for you for posting this report.
It is always easy to tell everyone about our successes but much harder to talk about our failures.
I am sure that you, Hans and the rest of the team have learned many valuable lessons from this incident and by posting this you have given others who aspire to this type of diving that chance as well.
I wish you a speedy and full recovery and good luck with your future exploration at The Pit
Regards
Steve
Steve Bogaerts

2 Patrick { 11.06.08 at 11:29 am }

Hey Steve,

Is all your fault!!! If you would not have laid that line so far back…hahahahah

I felt like I had finally revealed to the world that I am a fraud and that all my accomplishments were done by mere luck. When you called me and we spent like an hour on the phone you changed that and I was/am really thankful for that.

You are a true inspiration and I am very happy to call you a friend.

Cheers
Bentrick

3 lilo-mama { 11.07.08 at 12:50 pm }

Dein Bericht ist der Hammer, obwohl ich einiges nicht verstehe, habe ich doch verstanden, dass es sehr gefährlich war und du ein bisschen leichtsinnig warst. Ich hoffe, du bist bald kein Bentrick mehr! Bussi und ich bin stolz, deine Mama zu sein!!!!!!!

4 Etienne { 11.07.08 at 11:53 pm }

Been in that project is amazing. It’s a increadible opportunity to learn and by posting here you give the chance to other to be part of it in a way. Im prood to be in and I will support on the best way that I can.

5 John K { 11.09.08 at 6:35 am }

Hans

Thanks for sharing your experiences. Hope you are fully recovered. A question and a suggestion.

Question: Did you consider taking a trip to the chamber or getting yourself check for a PFO?

Comment: After finishing my CCR Trimix class I took a day of CCR Rescue training and it was very eye opening how difficult a CCR Rescue is in Open Water. This would be absolutely much more difficult in a Cave enviroment. I suggest in addition to the lifting device that you construct and practise several actual CCR rescues fully from inside the Cave including deco stops.

From your comments it seems you and the team need to break things up into smaller pieces. I suspect you thought you had already but maybe still smaller daily goals might make for a better result over time.

John

6 Jason { 11.23.08 at 5:52 pm }

Patrick and Hans,
hope Patrick is doing fine, hope to see some progress into the deep lines of The Pit.
UFC fights, only on TV, wait for full recovery before jumping in again!
Respect for being so humble.
See you guys around and hope to do some dives with you one of this days.

Jason

7 NT { 12.22.08 at 11:51 am }

Hi thanks for linking us and sending people to my website, I am glad you like it and hope it is useful.

In gratitude here you go have a grade 3 map of the Pit, hope it helps plan pit dives easier.

http://www.nick-toussaint.com/Projects/EJPP/ejppnews.html