Post date: Dec 2, 2019 11:52:33 PM

Team: Petie Barry, Matt Palmer

Time: 9 hours

Aim: Survey and push Mexican Passage.

It's now almost a decade since I was first in Mexican Passage, visiting with Artur Kozlowski, Tony Corcoran and Neil Tobin. In that trip we went as far as the end described in COFAC, a choke of calcited boulders. A few weeks I was back with Artur, and we hammered and crowbared the boulders until we were able to squeeze past into about 50m of tight sandy crawls. The farthest I got was a difficult squeeze into a bedding plane found at the top of a narrow rift. A few weeks later Éabha succeeded in passing this obstacle, crawling in for about 15m to another choke. With no-one able to follow her this remains unpushed.

I've had this spot on my mind for a while because

a) It was never properly surveyed.

b) It drafts very strongly.

c) It's heading into a big blank patch of limestone.

I managed to recruit Matt, mainly by not telling him too much about where we were going. We packed two bags with survey kit, capping kit, and a small crowbar. We went underground late in the day, at four on the button. An hour's caving brought us to the turn off for Mexican Passage. After calibrating the DistoX, we set off, with our first station on the wall of Legnabrocky Way opposite Mexican Passage. Here I found a nest of rather fine helectites, some of which were only a millimetre or two thick, and several centimetres long.

Mexican Passage begins as a large fossil passage with a misfit stream. It's quite grotty too - at one point I went in up to my knee in sloppy mud. Not far in you reach a 7m high slippery black flowstone wall - the Black Mass. I'd neglected to bring a rope to haul the bags up this, so getting the bags up was a bit of a challenge.

Beyond this some bouldery passage reaches the fun bit, over 100m of flat out crawling.The first bit is called Singing Despair, and is about .5m wide and .7m high for about 25m. I wasn't quite sure how we'd manage to survey and shift the bags, but we were able to do both, just about.

The dug-out squeeze was a bit more challenging, but once through we had sandy crawls alternated with mud crawls. At the end of these we reached a very tough flat-out section where we couldn't see each other despite being only a bodylength or two apart. This ended at the squeeze that Éabha passed. My worries about how difficult this would be to cap were confirmed on arrival. There was only room for one digger (and just about), and the squeeze was at the top of a narrow rift that you had to squeeze up to reach. I was clearly going to have to widen the approach first. After Matt wrapped up the survey I started the capping. First up was the snaggy squeeze up to the squeeze proper. The only way to cap this was to lie on my back and drill overhead, with drill flour trickling down onto my chest.

Firing the caps in this position was a bit tense, and exposed me to more of the blast than I'd like. The first cap fired but didn't remove any rock, however the second was quite successful, taking off a big chunk of the squeeze. After contorting myself into a kneeling position I could reach up and more holes drilled at the main squeeze, and painfully managed to position myself to fire them. The first pair didn't fire, but the second removed a lot of the edge.

I climbed up, removed the debris and tried the squeeze. Almost, but not quite. Could have forced it, but no guarantee of a return. Packing all the capping and surveying gear took a while in the coffin-sized space available to me, but eventually we were on the road, and crawling interminably back the way we came. By now much less fresher than on the way in, we became increasingly sluggish as we shoved and punched the bags ahead of us. Singing Despair was horrendous, with me effing and blinding and grunting almost the whole way along. Eventually we flopped out into the big passage, and stumbled about like new-born calves for a few moments, not used to this strange vertical position.

We got out just before 1am, pretty wrecked after a 9 hour trip. Unfortunately it looks like I’ll have to go back to the end of Mexican Passage with all the heavy gear since we didn’t make it through the squeeze. Despite the crawls only being just over 100m long, they’re quite exhausting, especially with bags. Once I forget how fucked I was in there I’ll be back.

We surveyed a total of 210m of passage, with 100m of big stuff to the start of the crawls and then the rest all tight and nasty. The crawling passage is surprisingly high, 15m above the level of the stream in Legnabrocky way. It drafts strongly, though this isn’t so strong at the capped squeeze. I wouldn’t be too worried about this however, since it’s a wide complex bedding plane area with numerous small cracks for the draft to vanish into. Where it’s going is interesting, generally trending to Monastir Cliff, 500m away. It may ultimately come from there, or Aghinrawn, or somewhere else on the on the surface in Legnabrocky.

- Petie