Category — Cave Diving Sites, Cenotes and Systems

Last week we returned to Ek Be for more cave exploration in Mexico. We decided to leave the west end for some time and focus more and more on the east end, trying to push it north and south.
At this point it was clear we needed one scooter per diver as the distance to the end of the line got bigger and bigger. The main issue though using a dpv is the restrictions and tight places that force us to stop and swim the dpv over and over again. Especially right after passing Cenote Ek Be, there is a restriction where the shroud of the scooter literally scrapes the ceiling and the bottom if you find the right place to pass.

But so far we continue to be lucky laying in average 2000ft+ per day. It is really an amazing place to dive as I hardly know any cave that is so intensely decorated. We need to move super slow and carefully to avoid damaging the cave. We cruise around at an average depth of 3ft and often end up in a dry cave and have to search for ways around it in very smallish cave. But its full of leads everywhere and often I feel like swimming through a sub level park garage in a huge supermarket. Using a compass while laying line is crucial in order not to swim in circles. The X1 dive computer is an incredible asset for this application.

Every once in a while we stumble upon massive flow riffles that are timeless indicators of the amount of water that used to run through these passages. It is a surreal and amazing trip though time.

Two days ago we did a double stage scooter dive with a two hour time laps between divers. The only way to pass the restrictions is to clip one stage between the legs while super-manning both the other stage as well as the scooter. Its a slow and painful process but beats the heck out of swimming for hours =)

The end of the line used to be 7000ft in, which took a bit more then an hour to travel. Once there two team members managed to lay together 2800ft of new line, not only adding this amount to the system but making important steps towards a connection with another system further north. The dives took a bit more then 4hours to complete but both explorers came to the surface with huge smiles, which were only slightly diminished by the thought of carrying 8 tanks and 2 scooter back out of the jungle.

Lastly yesterday an important discovery was made, a Cenote close to the end of line, a new starting point that would, at least for some time, save us the stages and dpvs and brought us to an arms reach close to a possible connection. Of course there is a little draw back, the Cenote is about 500mtrs away of anything that remotely resembles a road. So now we have to find it on land using our survey data and a GPS, then cutting a new 500mtr trail and start hauling our gear there for the first dives…We just can’t wait!!!

We will keep you posted!

We promised to keep you posted on the Ek Be exploration. Here comes the good news! We were finally able to dive Ek Be on April 8th and it was a very productive day with 3697 feet of the original lines resurveyed. We also added 244 feet of new exploration in just two dives!

The cenote we found and cut a trail to was named Cot Tunich. It is situated at the center of the cave system. It is a perfect starting point for our explorations. It has a wide cavern area that connects to cenote Ch’ul Nay. The distance between the two is around 200 feet. The cavern is a bit dark and has a ghostly hydrogen sulfide layer. Sunlight entering from a small window on the ceiling brightens the whole thing up and makes it really cool.

The cave runs mainly west to east and we can say that it looks like a branch of Dos Ojos running parallel to its downstream. We decided to resurvey the whole cave to have a uniform database to work with. While resurveying Ek Be, we would mark possible leads and push the end of lines when possible. The historical survey from QRSS showed 7189 feet of existing lines. It took us a few more dives to finish it all and then we really started to have fun, trying to go west towards Dos Ojos and east towards X’cacelito and Xel-Ha.

Westbound upstream explorations resulted in a connection with another small cenote. This is probably the cave reported as Scorpion Cave by Simon and Donna Richards in 2004, We also discovered a deeper cave level (50 feet) made of white flaky limestone, completely different from the upper level with wide bedding plains filled with cream color formations.

Over 3500 feet of new cave passage was added to the upstream alone, bringing it very close to Dos Ojos. The negative aspect is that it is becoming difficult to explore in this section of cave. We are finding a maze of narrow and unstable passages that connect a series of large collapse chambers. It won’t be easy exploration, but we will keep trying.

Going east beyond cenote Cot Tunich (Ek Be), we found a lead at the end of the original line that opened into an incredibly wide bedding plain. Much of the passage is very low, even for side mount configuration. Thousands of tiny stalactites cover the ceiling giving you the feeling of moving through a glass shop!

In a few days we extended the cave 350 meters eastbound towards the ocean, exploring almost 4000 feet of new cave. During the last dives we arrived at the pre-historic Plasticine Ridge where the old coast line used to be. As expected, the cave divides and turns north and south. The possibility of going through the ridge at this point is not known. There are a few cave systems where the tunnel is big enough to swim beneath the ridge. We will soon find out if this is the case at Ek Be.

Thanks for reading, more news will follow! Quiet Diver Team.

I am back in Mexico for a short trip and I gotta tell you I miss living here.  Living in New Jersey and raising a family is pretty damn fulfilling, especially when you have the coolest wife, son, family and business in the world.  But I still miss it.  It is easy to fanaticize about how much easier life was when we were living here with very little responsibility beyond getting coffee, diving and working enough to get by.  I know the reality is that it would be radically different with family in tow and the long term commitments and responsibilities that come with them.  But I know that you are not reading to get insight into the life of a repatriated cave diver.  You want to know where I have been diving, how cool it was and if, by any chance, I learned anything at all?

Well, today I woke up on Patrick Widmann’s floor (I got to travel cheap with a growing family), tossed all my stuff in his truck and we made our best time for Akumal, where I was to meet with Mauro Bordignon so we could do some sidemount diving.  Unfortunately, Patrick had a Stage Multi-stage course to complete today for two fine Swedish students, so he couldn’t manage my checkout dive.  Luckily, Mauro, one of our cave exploration partners and an instructor himself, was free to dive.

Mauro and I elected to try out a new cave for my checkout dive.  After debating Mayan Blue and Naharon, we settled on Cenote Regina.  Cenote Regina is just past Naharon south of Tulum.  It is a pretty cenote with a resident duck.  Access to the water is very convenient; however the water was a nasty green color, which I suspect the duck contributed too.

I broke out my gear which had been in storage and discovered that I didn’t have my booties with me.  I guess this is why we inspect our gear and do checkout dives.  We did some critical thinking and problem solving; arriving at the idea of wearing socks and flip flops in my ‘flippers’.   Truth be told, I had done this once before on a recreational boat.  Well, it worked out.  As long as I didn’t drag my heals on the cave, the fin straps stayed on.  I did get a little blister on the end of my right big toe, but it was well worth it.

Regina is a relatively deep cave.  Our dive averaged 49ft and maxed out at 79ft.  We dove for about 85 minutes on a set of side mount 80cuft tanks.  It is very nicely decorated and provides plenty of entertainment because it undulates and changes direction often.  The section of cave we dove is backmount sized passage.   There are many marked jumps.  However, on the way in we elected to stay on the main line.  When we returned to the entrance we decided to re-entered the cave becuase  we had sufficient gas reserves.  Mauro and I checked the second jump and found a very beautiful passage, cause both of us to ‘give the horns’ in celebration when we saw the passage.  The cave dropped down and turned into what looked like a perfectly half round passage with a brown clay floor at about 60ft.  When we exhausted out gas reserves we turned the dive and exited.

Overall it was an excellent checkout dive.  We had about 4 minutes of decompression on my LiquiVision  X1, which was no problem and gave me some time to chill out and enjoy the serenity that diving provides.

Tomorrow, Patrick, Mauro and I are supposed to check some ‘new’ in the Tulum area.  I will be sure to check in and update you.

I am back in Mexico again!  Allie, Griffin and I came down for a wedding and some much needed relaxation.  Luckily, I have the best wife in the world and I am going to get to do some diving as well!

For the first dive of the trip, Mauro Bordignon and I decided to check out Cenote Chemuyil Sur.  This is a beautiful cenote to the south east of Xunaan Ha.  It is also the cenote that spurred Alessandro Reato and Mauro to join me in surveying the exploring the 5th longest cave system in the world (more on this later).  I was resurveying the downstream section of Xunaan Ha to join up with some dry cave survey Jim Coke was doing.  When I reached the end of my lines, we determined that Chemuyil Sur was only 1000ft away and after discussing it with Alessandro, he decided to start trying to connect the two.  After a couple of months of work, Mauro and Alessandro connected the two systems!  This connection ended up being fairly significant because it is one of the few known connections that traverse the Plasticine Ridge.  Mauro and I wanted to visit the connection.

Mauro and I met at his place, got our kit together and headed to the cenote.  The dive started out uneventful.  The cave is manageable in side-mount.  However, as we progressed I started to get an uneasy feeling.  I was anticipating a restriction that we would soon reach and was feeling fearful.  Well, by the time we reached the restriction I wasn’t feeling super comfortable.  I wiggled into the chimney and determined I could most likely pass it.  However, I just didn’t want to do it today.  I stayed in the restriction for 3-5 minutes just meditating and trying to get to a “mind like water” place.  I was unable to get there, so I backed out.  I let Mauro pass the restriction and then he returned.

Mauro and I used the remaining gas to check a bunch of jumps and just have some fun.  The return trip for this dive was in reduced visibility or no visibility because of percolation and halocline mixing.

I am glad to be back in Mexico doing some cave diving.  A couple of things have changed since I left.

1. I have decided to add a z-knife on my right shoulder where both hands can reach it.  Previously, I wore one just on my wrist and in my pocket.  I am now carrying three.  This change was the result of watching Patrick and Mauro dive and setup their kit.
2. My level of confidence is way down from when I left.  And my skills/reflexes are off as well.  I am definitely a tourist again.  I am kind of bummed about this change, but to recognize it and obey it is satisfying.  Mauro, Alessandro and Patrick are all one percent-ers and I am glad they take the time to dive with me.  The work they are doing here is amazing and I am glad to call them my friends.

Beyond that, I am having fun diving again.  When I left Mexico, diving had lost some of the ‘fun’ factor for me.  Diving in NJ was a lot more work and I was overwhelmed by the rest of my life.  Now that Griffin is 6 months old and we seem to have things under control a little, diving has returned to being fun.  I am looking forward to a summer of diving in NJ!

Well… the last nine months have been pretty exciting!  My wife and I moved back to the US from Mexico during the height of Swine Flu scare.  We jump started our web design business, and had our son Hans Griffin.  As one might imagine all of the associated chaos put a pretty big crimp on my diving, however I was still able to get a bit of diving done. I made a couple of trips up to Thousand Islands and I did my first deep dive in the Mud Hole off of New Jersey.  But that is not why I am writing, I am writing because I am back in Mexico for a short trip to do some cave diving.

On Thursday I arrived full of anticipation and some anxiety.  Sol picked me up from the airport.  I had in tow a Silent Submersion DPV conversion kit, my side-mount gear and some other assorted dive goodies.  I was very glad to not have to ride the bus.   Sol dropped me off at Patrick´s apartment and I kicked back and started my wait.    As luck would have it, I came down with a cold two days before my flight.  The first two days here were spent waiting for my cold to pass and my sinuses to clear.  On Saturday, it finally cleared enough for me to dive.  I prepped my gear for a check out dive. 

Sunday dawned and Patrick of Protec blog fame and I decided to go diving.  We debated where to go for a while and decided to head to Cenote Azul.  I was told when I moved here that divers were not allowed to enter at Cenote Azul, so I never tried to get in there.  I said that to Patrick and he challenged me.  We decided to check it out and see if that was true. 

We pulled into the parking lot and spoke to the manager.  She was apprehensive but decided to allow us in, to my surprise.  She charged us each 100 Pesos.  She explained we could drive to the water, which was behind the shack.  Cenote Azul´s grounds are very nice and well maintained.  The walkways are manageable and the Cenote is gorgeous.  The water is about a 3 minute walk from the car.  The water is about 10-15 feet below the parking lot. 

You want to enter the water in the main cenote which is right in front of the wooden deck.  There are two lines at Cenote Azul.  One line runs to Kantun Ki and the other runs over to Cristolino.  You can swim to Ponderosa (Garden of Eden) by swimming towards Kantun Ki and taking a left. 

The main line to Kantun Chi is about 150ft from open water.  There are at least three viable options once you are in the cavern zone, however only the left one will lead you to the main line.  If you are looking for the line to Cristolino, you have to continue past the line to Kantun Chi.   The end of both lines are in the same general vicinity.

It took us about 4 minutes to get tied in.  We started up the line and stopped a number of times to make repairs.  One repair took the two of us to lift a 4 foot slab of collapsed lime stone  off the line to free it.  Another repair required us to cut a ball of line off the main line.  Lastly, we re-secured the line a number of times.  Every time I dive this area of the system I find numerous problems with the line.  In the past I have found the line slack numerous times and I find small collapses regularly here.   If you decide to dive here, make sure you pay attention to the line.  It is in the halocline and it isn´t in great condition, this is a relatively out of the way part of the system and the lack of traffic shows.

After about 45 minutes we reached Kantun Chi.   We turned the dive and headed back.  The swim home was uneventful and relaxing.  We surfaced at 100 minutes.  Overall it was an awesome dive.  I am really glad to be back here.   Diving in Mexico is much more relaxing then diving in New Jersey, there is no drive to the boat, no boat, and warm water.

The lesson this trip is to check out those old possibilities.  There are management changes, line changes and changes in perspective.

The advantages of a closed circuit rebreather in a shallow cave.

I have to admit that I recently neglected rebreather diving and instead spend most of my time off sidemounting. I pretty much used my rebreather for deep diving only. But recently that changed, I finished crossover training on the Poseidon Cis Luna Mk6 and right after that was with Howard, aka Scubadadmiami for a week of CCR Cave diving. And I am hooked on CCRs again.

The Mk6 exceeded my expectations but this is not what this article is about. What I want to share here is my recent experience diving Ponderosa, Taj Maha, Nohoch Nah Chich, Grand Cenote, Carwash and Naharon. Generally all the dive sites have an average depth of about 30ft and Nohoch even being shallower with Naharon being the exception at 60ft.

In many posts on CCR forums, the Mexican caves are described as CCR “unfriendly” and honestly I do not understand why? Our recent experience illustrated that CCRs can be used effectively in these caves and enabled us to get to know whole sections of systems in only one dive.

Normally when I guide people open circuit I choose a cenote and then guide two dives to the most famous or pretty parts of the system. The dives are usually turned either on time or gas which results in returning to open water. The option to recalculate thirds does exist, however, my opinion is that it should be reserved for experienced divers with experience in the particular system. When divers elect to recalculate thirds, eventually the gas reserve becomes to small to be safe.

The advantage of the CCR is that you have a bail out radius which enables you to spend as much time as the scrubber will allow, normally about 3 hours which is a huge opportunity here in the Riviera Maya.

The cave systems here are like Swiss cheese with many different side tunnels and passages. They are also very shallow. These two characteristics combine to create a situation where divers have a very long range on an 80cuft cylinder. Depending on you gas consumption while bailing out and conservatism factor you want to build in you will have a radius of at least 40min in most places. There are other benefits worth mentioning:

1. Once you come of the frequent traveled passages you will often encounter quiet significant amount of percolation that can seriously affect the visibility.
2. Thinking about the lost line or lost diver scenario, imagine how your chance of survival or the chance of finding your dive partner will increase with an hours long supply of breathing gas.
3. How many accident reports have we seen that speak about people drowning only minutes away from an exit, what would have happened if they would have been on a rebreather.
4. Taking pictures on the way, on a CCR you penetration distance is not going to change because you stop at a place to take some pictures or simply take a brake.
5. Think about a reverse block way back in a cave, how much more relaxed are you going to be, knowing you can stay there fro hours.
6. No time or gas pressure to go to a certain part in the cave and therefore reduced chance of pushing limits due to being goal oriented.
7. And many more

Of course this is a double edged sword and there are as well some negative aspects:

1. Buoyancy is definitely more difficult.
2. It is the perfect tool to bring people that where before limited by their air consumption far into the overhead environment and by that outside of their comfort and experience zone.
3. With most units together with the bail out your overall size in the water column is bigger and therefore you need more effort to travel.
4. Many ups and downs consume Oxygen and Diluent volume.
5. Getting overconfident due to the feeling of having unlimited gas supply.
6. Proper bail out gas and volume is never an issue until it becomes an issue.
7. And many more

To have a real advantage with the CCR we have to change the way we dive in the cave. Instead of using it to go for that record braking long distance penetration why not stay closer to the entrance but get to know all the lines that are in that area.

For example, at Naharon we dove up the main line and did the Jump towards the double domes. We swam up that line until we reached 40min, or bail out distance. On the way we stopped several times to take pictures and simply stopped the timer while we did not go further in the cave. On the way we marked the double set of line arrows that mark the jump towards south western sac be. On our return we arrived back at the arrows and new that from this point on we had 30min for further penetration so now we did the jump and enjoyed the really unreal beautiful sac be section.

On the way there we pass yet another set of double arrows marking the jump that lead down towards Cenote Mayan Blue and again marked it. We continued in the sac be tunnel until we had reached 30min from the jump and turned our dive. On the way back we stopped again a couple of times to take pictures. We didn’t even have to take care about the time since we were well inside our bail out range.

As we arrived back at the Arrows we decided to make yet another jump and check out the line that leads towards Mayan Blue. After some time we turned from there and now did the entire return trip back to Cenote Naharon.

As you can see, we did in one dive what, in conventional OC cave diving style would need three dives. We had an average depth of close to 60ft with a 180min runtime, me carrying an 80cuf and Howard 2 40cuf bail out tanks.

Another example would be Carwash where we could use Lukes Hope to restart the 40min bail out range and therefore had plenty of time to visit the room of tears and all the different Ts in the back. On the way out we did the jump that leads to the back of the room and stayed there for like 30min just doing pictures and enjoying the decorations.

In Grand cenote we went down to the Cuza Nah Loop and could restart the 40 min each time we past a cenote which was awesome since this gave us the possibility to do the jump at the mid way of the loop and take our time while swimming down that line again taking pictures and having a great time. On the way back we continued the loop on the other way since we were still easy inside our bail out range.
And the same was done in all the other places.

All in all I really enjoyed this week especially the possibility to visit lines I have not been too in a long time. I really love to do complex navigation, see different lines and go back and forth and all around.

Another bonus, so to speak, was to get more experience on the Kiss Classic which I really start to like more and more for its simplicity, the 20min prep in the morning and the 5min tear down in the evening, the free chest, constant O2 flow which facilitates buoyancy and the general possibility to keep the same configuration than with a set of doubles.

For Howard it was great too because he really got to know quiet a bit of each system we dove at, although he only did ONE dive there.

Considering all of the above, I would call the caves here perfectly suited for CCR diving if you bring the right set of skills, a good attitude and some creativity to the table.

Of course there are always people that say OC backmount is the only way to go and others believe that OC sidemount is the best, then there are some that believe in multiple stages or scooters or I don’t know what else; Me, I think it all has its use and its just what you do with it that makes it valuable. Try to get the most advantages out of whatever equipment you use and try to work with the right tool for the job!

Keep the loop closed but your mind open!!!

Patrick

I posted a link to my article Last Dive at The Pit – Bailing Out at Depth over on Rebreatherworld.com.  One of the users, zzzzzzzz, commented on it and I thought his comment was worthwhile reposting here with my response.  The indented copy is zzzzzzzz’s comment.

Good article.

WRT keeping on schedule, OC trimix should be running a set of schedules, allowing for aborted dive, short, long and maximum schedules. This provides all the needed flexibility in an emergency. Running a single schedule is not great.

Thank you! I write the articles for people to learn from and enjoy as entertainment.

The diver had the appropriate schedules. I am not sure where you read that we didn’t have the schedules. Seems like you made a bit of an assumption to the negative. Our desire was to stay on the nominal schedule. As you might imagine, the switch to the next schedule at depth can add an unnecessary amount of decompression and gas usage. Every minute at that depth translates into about 5 minutes of deco. A switch to the next schedule brings a 30 minute penalty, something neither of us wanted to be obliged too. A close reading of the article reveals that my one minute to make the switch was built in to our nominal schedules. We left the switch on schedule.

This is to distinguish the need for time to solve problems versus making an expeditious exit. Since you experienced issues, it is astounding that the OC diver’s schedules did not allow flexibility in running schedules. Certainly, a diver targets a nominal run time for a dive, however, not carrying contingency schedules is a fundamental training issue. Recommending that someone executes faster when encountering problems is not constructive since one cannot predict how long problem solving can take, especially in an emergency.

See above.

It is also quite okay to encourage better skills integration for enhanced performance, however, not because it is an inconvenience for the OC diver.

I see his recommendation in a different light. Optimally, I would like to be able to be swimming towards the exit while making the switch. That ability would cut at least 1 minute at depth and 5 minutes off of deco saving a little less then 18cuft of gas. Additionally, it would put me closer to the exit if there were another emergency, which out of respect to Murphy isn’t completely unlikely. I can’t remember a time when only one thing went wrong when things started to go really wrong. I think Santiago’s critic is correct in that I need to work towards the ability to swim and make this switch at depth. I can do it in 100ft, why not in 280ft? That is a valid question and needs to be figured into bail out planning and needs to be trained further to develop better muscle memory. I don’t think either of my CCR instructors would have let me walk without being able to do that skill while making an exit. I shouldn’t accept it either.

On deploying and stowing regulators, especially on the fly, an added option is to set hose lengths such that the regs drape around the neck to staggered positions. This can allow maintaining several regulators in a deployed condition, allowing more time and options for stowage.

This is not a bad recommendation though going back onto the loop and doing 2.5 hours of deco this way wouldn’t have been very comfortable. Again, this is a training and equipment issue and was only identified because I took the time to actually try it out.  I wrote that I have a similar problem when I dive OC with stages.  That should have been a warning to me that it would manifest itself when I dive CCR.  It is interesting that the problems we have in the shallows are magnified under the time pressure that comes with depth.

Thanks for taking the time to read my article and provide feedback! Your ideas help me to better flush out my ideas. Keep them coming

If you have been following Quiet Diver, you know that I left Mexico a couple of days ago.  And while I was in transit, I was torturing you with stories that were unrelated to diving.  Well, this story gets us back to writing about diving!

A month or so ago Santiago and I made a dive at The Pit down the Lins/Walten tunnel.  It was a nice dive to 238ft (73m).   Santiago was diving OC and I was on the Megalodon.   After the dive we had some helium left over and we enjoyed diving together so much we decided it would be cool to do a dive to the back of Wakulla Room as a team.  Additionally,  we needed to pick up some tanks that were staged from the last project and I still needed to do my at depth bailout.   So, we got another tank of helium and decided to do the dive in a couple of days.  Well, as the date approached I was too overwhelmed with work and had to call the dive.  These dives require a lot of preparation and mental focus and if my mind is on other issues, then I can’t do the dive.

Well, it took me more then a month to reschedule the dive between work and social engagements.  But once we got the dive scheduled everything fell into place.  All the gases were blended, regulators prepared and dive plans cut.

The plan was to stage gas at 20ft (6m) and 70ft (21m) on a down line.  Then set the primary reel and stage gas at 150ft.  For bottom gas Santiago took double 80’s and a deep stage.  I took two 80’s of deep bailout and the CCR.  Normally, I would carry one deep bailout for this dive, however since I was going to purposefully bail out, I thought it would be wise to carry extra gas.  As well, I was diving with an OC buddy and I wanted to be able to donate gas in the event of a lost gas situation.  After staging all the gas, we planned to swim to Paul’s Rock, which takes about 16 minutes.  Paul’s rock is about 800-900 (274 – 278) linear feet (meters) from the surface at a depth of 280ft (86m).  Upon reaching Paul’s Rock, I would signal Santiago that I was bailing out.  We would spend one minute sorting out the situation and then make for the exit with haste.  After exiting the Bypass, I planned to switch back onto the loop to conserve gas and do a normal CCR decompression schedule.

I had a several reasons for bailing out at depth:

1. Switch from a rich HE mix to a lighter mix and experience a change in END and confirm our choice of deep bailout.
2. Go through all the steps of bailing out under the effects of depth.
3. Confirm my SAC rate in that configuration and under the environment stresses.
4. Practice bailing out under the supervision of a trusted dive buddy at depth and get critical feedback.
5. Complete the drill because I made Patrick complete the drill and he was riding me about it.
6. Feel the tanks as they get really light with HE in them.
7. Breath open circuit gas at depth while hustling.  (I never dove Trimix OC.)
8. Practice, practice, practice!

The dive went nearly as planned.  We reached our way point at 150ft (46m) a little late, through a little effort we were able to make up the time and we reached Paul’s Rock on time.  I turned to Santiago and gave him an okay.  He replied.  I then gave him the bailout signal.  I reached up and turned the knob on my BOV.  I breathed out a little to clear the regulator of water and took a breath.  As I completed the breath I was immediately hit with a case of nerves.  I felt a shot of anxiety and adrenaline wash over me.  It was totally unexpected because I had mentally rehearsed the drill a pile of times and had executed it in shallower water many times.  My brain went a little mushy.  I reached around and opened the bailout tank valve.  For reference, I have my bailout tank and diluent tank plumbed into a manifold, so I now had access to both.  I had switched from an END of 67ft (20m) to an END of 92ft (29m).  Plus I went from an “unlimited” gas supply to a very limited gas supply.

After opening the bailout tank, I pulled my regulator out to replace my BOV.  As I pulled the regulator to my face, I reached up and pulled the BOV out of my mouth and thought to myself, “Don’t flood your unit – close the BOV.”  I reached around and switched the knob, opening the loop!  Dur! I heard the bubbles and quickly stuck the loop in my mouth.  I switched the loop closed and cleared the regulator.  I thought to myself, “You idiot!  That is exactly what you needed to not do.”  I took the BOV out of my mouth put the regulator in my mouth.  Confirmed I was breathing the right gas and looked at my set point controller.  I needed to set the set point down to manual.  It took my four tries to get it right.  I kept setting it to 1.4 instead of manual.   Finally, I got it set and then switched my X1 over to bailout, which I achieved on the first try.  I opened the OPV and started to swim.  The whole switch over took about 1 minute.  However, it really felt like a life time.  We swam for 5 minutes exiting the Bypass.  I switched back to CCR and made all the appropriate adjustments.

As we ascended, I picked up the staged tank at 220ft (68m).  The tank had been there for almost two months.  It was covered in billowing clouds of bacteria.  All the hoses were slimy and I was very glad I didn’t have to breathe from it.

The rest of deco went smoothly and was without incident.  Santiago and I had very similar schedules and exited the water pain-free.

As I hovered in deco, I had a lot of time to reflect about the dive.  The first thing that came to mind was how glad I was that I took the time to do the drill!  I wish I had done the drill last fall, when we first agreed that we would do it.  There is no harm in practicing this stuff, except to your wallet!  There is only benefit and experience.  Because my Meg is so reliable, I do not often get the opportunity to bail in a stressful situation.

Bailing out at depth in the back of a cave is different then bailing out in the first 1000ft (309m) of Ginnie, any shallow cave in Mexico or on the Jodrey.  I had bailed out repeatedly in those environments and never felt the anxiety or lack of coordination that doing it in The Pit caused.  I was definitely noticeably more impaired at that depth, even with a 96ft (29m) END.  I was glad to learn that my SAC rate held even at depth with a shot of adrenaline and a hasty exit.  I was also glad that I was able to get all the required tasks completed.  After the dive, I checked my loop for water and there was very little.  The towels in the bottom of the can were just a little wet.  So the open look fiasco wasn’t too detrimental.  I was glad that I identified that problem quickly and resolved it.

Santiago was concerned with how long it took me to bailout.  As he was on OC and run time tables the whole dive, he really needed to stay on schedule.  He suggested that I might have been better off starting to swim earlier.  I don’t know that I agree.  I think it is critical, even if I waste 1 minute, to get everything set and then start to swim.  I can only do one thing at a time in a situation like that, especially if my lizard brain starts to emerge.  In past situations, I really fumbled things by trying to do more then one thing at a time.  I have learned I need to complete one task then move on.

In response to his remarks and my performance, I would like to go through the drill again at depth a couple of times and maybe a couple more times in mid-range water.  I think when I get back to Q. Roo, I will schedule another bailout before I start deep diving activities at The Pit.  I may have the opportunity to give it a try this summer here in NJ.

Santiago said I looked somewhat impaired as I tried to set the handset.  I agree with his observation, I was.  Either it was anxiety or being narced.  I think it was an insidious mixture of both.  I know that when I get scared or nervous, even in shallow water, my cognitive abilities diminish.  Mix that with some depth and you have a nice cocktail.

Lastly, he was unhappy with how long it took me to get back on the loop and the distance I swam off the line when I switched back to the loop.  Both are valid concerns.  I swam off the line to avoid getting entangled.  As the line exits the By-pass it splits in two and ends up above you and below you in ugly spots.  So, I swam away from it.  As for taking too long, he was right.  I had a lot of trouble stuffing the hose back on the tank and as I was about to pick up another tank I needed to sort the bailout first. I think I need to get looser hose retainers and practice with them a bit.  I have a similar problem when I am dealing with my OC stages.

I am very happy with the dive.  It didn’t go perfectly, but I learned a lot and we had a ton of fun.  I am grateful to for my friend’s observations.  When you are in the moment, you miss things sometimes and a neutral observer can add a lot of depth to the discussion.  Santiago is an excellent diver and I look forward to my next opportunity to spend time with him.  I am sad because that was my last dive at The Pit for a while!  I really enjoyed diving at The Pit, especially the deep dives.  The Pit is a spiritual place for me.  I see it as a cathedral of diving.  The spaces are so big and beyond normal scale that it inspires me.  Until next time, I will dream of diving at The Pit.  To be honest, I am going to miss all my friends: Patrick, Solomon, Alain, Steve, Etienne, Ross, Katie and Santiago just to name a few.  The last year and a half of diving has been amazing and I have many fond memories.  Thanks to all of you, my life is forever enriched!

Patrick and I decided that we needed to go for a nice easy dive, one that wouldn’t include a huge pile of tanks or the mixing of exotic gases.  The answer seemed clear, go looking for Cenote Pabilany in Sistema Sac Actun (Grand Cenote).

The journey to this decision started last year or the year before. Patrick was diving his Megalodon in the western end of the Sistema Sac Actun.  He was near the Pabilany section but he was on the Paso de Los Pozos side.  He wanted to continue but found the restrictions a bit tight in the rebreather.  He finally retreated and decided to return in sidemount.  As time passed, the idea of diving this section of cave stayed with him, I moved into town and then we both got scooters.

With all the requisite gear and skills, we decided to scooter up there in sidemount with a single stage to check things out.  We sat down on Tuesday night and spent a couple of hours debating the best gas management rules for a scooter dive of this nature, finally settling on what we believe to be an innovative approach.  Secure in our planning we decided to dive on Thursday.

The dive plan was as follows: scooter up the main line jumping to the Paso de Lagarto. Continue scootering eventually jumping to the line to Lithium Sunset. When we reached our stage pressure or the T at Lithium Sunset we would stage the scooters and the tanks.  We would swim north on the Lithium Sunset line looking for the jump into Pabilany.  Once we found it, we would make the jump and a short foray into that section of cave.

The dive went almost according to plan.  The first obstacle was planning the dive.  Looking at the cave map and estimating the depths it looked like we might get into some deco with air.  Therefore, we decided to take O2, luckily the average depth was much shallower then we anticipated and the O2 was unneeded, which brings us to the irony of this dive.  Patrick and I wanted to make a simple relaxed dive.  Instead we ended up needing 4 tanks and a scooter each.  I guess when you compare that to needing 6 people and 35 tanks, this was a relatively simple and easy dive, but it was still not a no-brainer.

The second small obstacle was an exiting team.  When we got to the jump off the main line, there was a team of three exiting in backmount swimming with double stages.  We gave them the courtesy of waiting for them to completely exit the area before installing our jump.  This ended up taking 4-5 minutes as they lumbered through.  Not a huge deal, but hanging out and waiting, cuts into your stage and scooter time.

When Patrick and I scootered up to the T, our run time was about 23 minutes and we were both nearing our stage drop pressure.  It was serendipity.  We dropped our scooters and then our stage tanks.  In those 23 minutes, we coved about 2300ft, installed two jumps and a primary reel.  It was awesome.  The last time I swam to this spot it took us about 55-60 minutes to reach it.  I felt like we made pretty good time!

We started heading north looking for the jump.  We came to an arrow and decided to make the jump left.  We swam past a T, taking it to the left.  At this point the cave got tight with an aggressive saw tooth shape.  Then the line doubled back on itself and disappeared into a no-mount restriction.  Well, the truth is Patrick made it through with both tanks on and I had to remove one tank to pass.  The line through the restriction was on the ceiling in an awkward position.  Patrick squeezed through first with a lot of silting.  I followed him using the brail method.  The restriction required angling the body and ascending.  It was challenging and doing it in zero visibility made me nervous.

On the other side the cave opens up a bit and then pinches down.  I started to follow Patrick up, but the silting was just too much and my nerves were starting to fray.  Add to that the line was slack when we first entered the room and Patrick was actively fixing it as I followed.  Finally, I ran into his fins and decided I had enough.  I backed out and into the bigger room.  I decided to wait for him and meditate a bit.  When he returned a couple of minutes later I gave him the “Turn the Dive” sign.  By this time I had calmed down however he could tell I was a bit scared by the look on my face.  I hovered for a minute more and meditated.  I wanted to relax and prepare myself for passing the restriction a second time in zero visibility.

I descended back into the restriction and got a little stuck.  After a couple of seconds of fidgeting I popped out the other side and a wave of relief washed over me.

There is something exponentially more terrifying about following someone in extremely restricted silty cave then leading into that same environment.  All I could see was waves of silt coming down the slope, I had no idea where we were heading.  It ends up that Patrick surfaced just ahead of me in Cenote Azteca.  The last jump we made wasn’t to Pabilany at all.  We had missed the jump to Pabilany.

Once Patrick came through the restriction we gave each other the fist and started our return swim.  Our short stint up to Cenote Azteca didn’t use much gas, maybe a couple hundred PSI out of each tank.  So when we arrived at the T, we decided to check it out.  We swam north at a leisurely pass.  The cave was bigger and relaxing.  We passed over at least one jump and finally turned the dive at a single tank no-mount restriction.  We were nearing our turn pressures so we didn’t attempt the restriction.  When we reviewed the map we discovered we were in First Hope.

The trip home was flawless and we used less gas then on the trip in.  When we reached the O2 we had 90min of NDL, which was a comforting discovery.  Patrick and I both found the dive very satisfying.  It included sidemount cave, scootering, no-mount restrictions, and some very beautiful cave.  Our gas planning worked like a charm and gave us additional flexibility in the execution of the dive.  The only shortcoming was that we didn’t find Pabilany, though it did result in the happy accident of finding Azteca.

Patrick and I are happy to announce a HUGE success at The Pit.  After a lot of deliberation yesterday morning and discussions with our partners, we decided to make a single alpine attempt at pushing the end of the line at The Pit.  We came to the conclusion that using the habitat and support was too much of a burden and elected to go to the end of the line with one scooter each, no support, zero VPM-B conservatism and limited bailout.  We decided to not use bailout after we realized that loading 35 tanks into the jungle was more of a risk then the possibility of bailing out.  Additionally, we recently perfected the team skill of CCR buddy breathing.

On Tuesday morning, we packed up our gear and headed to the dive site about noon and were in the water at 1PM.   The decision netted a significant addition to the end of the line.  We are still tabulating our survey data but it looks like we added more then 1500ft of line.  The dive took us about 7.5 hours using 7/70 for diluent.

I want to thank our significant others for supporting our effort and the rest of the team for not standing in the way.  The dive was a huge success and will serve as a model for future dives at The Pit.

If you are interested in learning CCR Buddy Breathing, I can make a video of it available to you directly for $4USD per copy.  In a couple of weeks, we will write a full article on our recent success and we will be posting our raw survey data on line in the name of safety and future dive planning.  We expect Jill’s Chamber and Next Generation Tunnel to be a popular dive site with the launch of the new Mark 6 Technical CCR.

Note: This was an April Fools Day post…..  Your milage may vary.