Jackson Blue 12/24/11

[Unregistered User]

I left Lake Geneva at 7:45am and made the trek up to NW Florida to meet KarsticGator-who was already in the area- for a dive in Jackson Blue. After getting fills and buying all sorts of new gear at Cave Adventurers, we then headed to the park entrance. We arrived at around noon and began unloading gear. During the setup, we met Edd Sorenson who gave us some good info regarding the numerous line tees within the system.

Adam then remarked to Edd that he saw a Shearwater DC in his shop and was interested in seeing it in action. Edd just conveniently had a spare one with him and showed Adam and I all the functions and offered to let Adam use it for our dive for testing purposes. Edd then went back in the water to continue a class he was teaching while Adam and I continued setting up our gear and hauling DPVs and stage bottles to the water. We also met another diver named Vince who gave me detailed descriptions of the two goldline tees and which direction would be the ideal one to take, considering that we would have a lot of gear.
I have done less than a dozen dives in JB and the furthest I had ever been was just past the trash room. We decided that we would each stage 1 AL80 and then drop that and then continue on with back gas. I would carry an additional AL80 for a bailout along with towing my Mako DPV as a backup. I was hoping that we would reach 3000' but it didn't really matter, so long as I got to get underwater after driving 4 hours in the morning.

After suiting up, we entered the water where Adam managed to tear a nice hole in his drysuit wrist seal. We brainstormed for a while and found there was no way the dive could made in its current plan. Adam would have to cancel the long DPV dive. That truly sucked for him...not so much for me.

I modified my plan to allow me a safe solo dive: I still carried the two AL80s and my steel 72 for deco along with the backup Mako. I would just breath my back gas (double PST 120s) using only a 1/4 of the fill pressure and then turn the dive, never factoring in the 2 stage (now deemed bailout) tanks into the dive plan. I then took the shearwater DC from Adam to compare it to my Cochran EMC-20h during the dive.

I dropped the deco bottle well inside the cavern and then continued on. The goldline was in excellent shape all the way to the 1st tee with arrows preceding the tees by about 25' and the tees themselves marked with line arrows as well.

After dropping the Mako backup DPV and one of the AL80s, I continued on while breathing back gas and carrying my last bailout bottle. The stretch past the last goldline tee was scootering heaven and I noticed that there were distance arrows well-marked throughout. All the subsequent white-line tees were well-marked as well. I believe there were 4 of them in all. I still had tons of gas available when I reached 3000, which came very quickly. I thought "well, I'll just go a little further until the next bend or if it becomes small). The 3300' marker came and went and yet more borehole stretched out in front of me, beckoning me to come in farther. I obliged the cave, and held the trigger down...3500...3700...this cave just stayed big and the DPV made it effortless. Then the cave narrowed a little around 3800 and I saw a lot of 'elephant tracks' in the clayey floor. I stopped at a slight bend at the 3900' marker and still saw scooterable cave beyond. But I had already burned through 800 psi of my original 3700 psi fill so I felt that I had gone far enough and should head back and gloat to Adam the great peaceful dive I had. My bottom time was now at 31 minutes and both DCs I was wearing showed about :11 of NDC time left.

Going out was a blast and I only stopped once in a large area just outbound from the trash room to try out a new Intova LED light I bought. The light used 6 AA batteries but was still small enough to fit inside my drysuit pocket. I hovered and let my primary light head hang below me so to not illuminate the cave. Then I turned on the Intova and was taken aback at how much light it threw out. The beam was focused to a laser-like point and would make a great signalling and alternate backup primary light. It did not emit much scatter so any illumination more than 10-15 feet from the hotspot was minimal. I stowed it and continued my way out, eventually grabbing my Mako and last AL80.
I passed a solo rebreather diver around the 700' marker and then a single cavern student with instructor near the entrance. Both computers showed a :06 stop @ 20' so the deco was almost non-existent. I hung around the 20' stop for about 8 minutes breathing my O2 before exiting the cavern. What a phenomenal dive!

[nefiii]

Great report! Thx for posting.