Lower Thunder River
Kohl Mitchell, Cathleen Yung, and Myself were the first crew of many to enter Carroll Cave at about 9:30am
on 8-29-2022. I rappelled down first to check that the rope we rigged the night before had made it to the bottom.
After successfully reaching the bottom, Kohl came down, and then Cathleen. As we were taking off our vertical
gear, Chad McCain had entered the cave and was waiting for the rest of his team.
Our objective was the DL2 lead along Lower Thunder River, just past the Little Lake Room. The trip down was
uneventful. Having been the first time for Cathleen and Kohl being in that part of the cave, we made some quick
sightseeing stops, but ultimately we kept a pretty good pace swimming down “The Forevers”. We reached DL2
at about 11:10.
We left Thunder River and started getting out our survey gear. I had with me my two personal DistoX2s and a
CRF DistoX2. All of which agreed well when tested on the surface the night before. Kohl took point on the
survey while Cathleen was on frontsights. We had to first recover a tie in station from the Thunder River
survey. Dan Lamping gave me a map cut with survey line that showed station BR2 at the start of DL2. We
found a conspicuous looking mud pyramid atop a mud bank in the area that the map showed. It had no flagging
on it, but we took a chance and started survey there. Weu re-marked the station in white out and we headed
into DL2. We kept our fullbody wetsuits on.
As in most cases in Carroll, we immediately found ourselves in sloppy, boot sucking mud. DL2 is basically a
series of mud banks with a small meandering stream that cut down several feet in between them. Kohl took a
spill as he made his first steps into the slop, but he did well in keeping the Disto clean.
Kohl placed the first station, DL2-1, just inside the start of the lead. Cathleen setup at BR2 and they took the
shot. It came back something around 219.9 / 37.8…. first shot of the day, a solid 2 degrees off…. so we started
troubleshooting. We tried just about every trick with the distos and could not get a better agreement. Finally I
got up and took the frontsight myself and immediately got a number that agreed within 1 degree. At this point I
set the disto on the ground with the laser on and asked Cathleen to slowly walk towards it. As she got within a
foot or so, the azimuth changed by a few tenths of a degree. I then asked her to crouch down where she was. As
she did, the azimuth jumped several degrees. I asked to see her helmet and quickly found the culprit. She had a
Fenix 18650 headlight with an integrated neodymium magnet in the cap. That magnet was nuking the magnet
field around her. So we yeeted that thing and I gave her my spare Zebra light then all was right with the world.
Kohl and Cathleen quickly found their stride and were working well together in placing stations and taking
shots while I sketched the measly passage at 1:50 scale. Soon enough I heard Kohl say “I see why we brought
the shovel”. At Station DR2-8 is the known “end” of DL2. Tony Schmitt and I had checked out DL2 while
heading out of the cave on a previous trip. I knew the dig was there and was prepared to dig it open this trip.
The team decided to go back to Thunder River where we left our packs and eat lunch before starting the dig. We
all had freeze dried meals and shared a single stove. We used a sawyer filter to collect water out of Thunder
River for Kohl’s meal. Cathleen and I lit some large candles for some warmth while we ate. During this, Kohl
found that his boots were starting to fall apart. Cathleen had a roll of tape that he used to wrap his boots a few
times. We made our way back to the dig soon after finishing eating.
I got to the dig first and got to work. To my surprise the mud was hard packed and was coming out in dense
chunks. I dug down to set the height of the dig and got about 1 foot in before handing the shovel off to
Cathleen. She went head long into digging and easily tripled the size of the dig. She handed the shovel off to
Kohl and he did about the same amount of work. He just about broke through before handing the shovel back to
me. I crawled in and started stabbing at the end of the dig. Finally a chunk broke off and the dark void at the end
grew bigger. I worked on it a bit more, but handed the shovel off to Cathleen as she was next in line and had yet
to experience breaking into virgin cave. She crawled in and quickly disappeared. The sounds of her excitement
indicated she was through. Kohl made his way through after her, then I followed.
About this time, I unfortunately had a headache setting in that was slowing me down. We looked ahead to see if
the passage continued. Immediately passed the dig was another room with two ways on. One to the left went up
into another room with no continuation. To the right was a small rock opening that lead to a corridor about 5
foot in diameter and 50 feet long before it turned right. It had a mostly flat, unmolested mud floor. The mud was
firm as well. At the end of the corridor was another room. Here there was a small, decorated dome that was
dripping water. At this point my headache was getting stronger. I laid down and asked Cathleen to go a bit
further to see what the passage did. She found that the passage continued the same and then we headed back.
When we got back to the virgin side of the dig. Cathleen and Kohl started working on opening up that side
more. Cathleen suggested that I head back to my pack at the main passage where I had some tylenol. I did this
while they dug.
While I had intentions of pushing survey into the virgin passage, my headache wasn’t allowing for much focus.
I got back to my stuff, took tylonel, and hydrated. Kohl and Cathleen showed up a little while later and brought
all the survey gear with them. We opted to pack up and start heading out given my condition.
On the way out I began feeling better and we stopped at a high lead just below Black Rock Riffles to try to see
what it did. We first tried to get to the lead from a bit upstream where there was a sloped ledge up to a ceiling
dome. We spotted Cathleen as she climbed up and looked around. Unfortunately, there was no connection.
After this I took a shovel and skirted my way along a sloped ledge above the stream till I was right below the
lead. I lost my footing once ans nearly went for a swim, but caught myself. Looking at the lead up close, it was
obvious that there was no safe way up into it without bolting or a ladder. I returned to the stream and we headed
When we arrived at the backdoor entrance, Bob Lerch was getting ready to start his profile sketch of entrance.
Bob gave us the opportunity to make our way out before he got started. Cathleen was feeling rather chilled so
we sent her up first. Kohl followed, then myself. We exited at about 8pm.