Dive Profile downloaded from a DiveRite Nitek3
The above is a screen shot of my last dive at Jackson Blue Springs. On this particular dive, I used a set of PST 121s with 27% Nitrox (this mix was filled for a different dive and never used), 1 AL80 stage bottle with 33% Nitrox (my normal blend for this cave), and 1 72cuft O2 bottle set at 20 feet for decompression.
As you can see, I ran the stage bottle in for 20 minutes, this put us at the first T (or better known as the "Y") which is approximately 1000 feet into the system. Here I dropped the stage bottle off, and secured it to the main line and continued on with my backgas. (In yellow) We negotiated Court's Squeeze (1300 feet) and checked air and time, 26 minutes. I doubled checked my timers at this point, as 26 minutes is the fastest run myself and Pete as a team have made it to this point. (Flow is down) We proceeded on, and once at the Stop Light (2100 feet) checked air and time again, 37 minutes into the dive. To date, the Stop Light had been my furthest penetration into JB. However, with the 121s I had plenty of gas left and we continued on. Within a couple hundred feet we were crossing over the Trash Pile, this area is littered with bottles, beer cans, clothes, you name it. It is believed that there was once a sink here or possibly a well that someone filled up with garbage. Another hundred feet or so, and we came to a sharp bend to the left. You can definately tell that this portion of this system does not get seen very often. It is beautiful and immense, rolling hills of sediment, undisturbed, reach as far as your light can penetrate, in either direction of the guide line. There is also some very interesting fossilized remains of sea biscuits, and such in this area.
We continued on for a total of 13 minutes after the stoplight, at this point we called the dive, not because of air supply (myself, I would have called it soon enough, I was 100 psi from 1/3s, however Pete had another 300 psi to go) but because of fatigue. A 3000 foot penetration into Jackson Blue without scooter is definately a work out in my book.
I
posted this as a aid for anyone planning on diving Jackson Blue, so you can have
an idea of the profile. Safe diving, and have fun!
David O'Daniel