After the breakthrough into big going river passage on June 14th, everyone in the ISS was eager to return and see where the big river went. ISS members realized the 40-mile milestone for Binkley cave system was within reach. After their grueling 15+hour trip, everyone needed a week or two to rest and allow their bruised bodies to mend. With the 4th of July holiday upcoming, the return trip was finally scheduled for July 12th.
Many of the key ISS members intended to go; so Rand and Dave made plans for four survey teams of three cavers each. One person became ill at the last minute so eleven people left Frederick’s after a hearty pre-cave breakfast around 10am on Saturday morning. It was hot, but with no chance of rain, so the cavers needn’t be concerned about the weather with a long trip ahead of them.
Excitement was in the air as they walked beside the rapidly growing corn to the Miller’s entrance sink. It took about five hours at a steady pace with a couple of short breaks to reach the frontier. Most of the participants had never seen the new river before. Brad, Shane and Chris had arrived first and already started the survey upstream. The other three teams caught up, split up and started leapfrogging each other up the river. The passage was large and travel was quite easy- totally different than the passages they had traveled through to reach this point. Survey progress was rapid. It seemed like no time and they had charted over a half-mile of new virgin survey where no one had ever set foot before.
About ¾’s of a mile upstream, they entered a huge room – possibly the biggest in the entire system (depending on how you measured). The breakdown room was enormous by Indiana standards with a broad perfectly flat gray ceiling overhead. Certainly the rock had to be either St. Genevieve limestone contact or the thick beds surrounding the Lost River chert. The generally thin-bedded St. Louis limestone most of Binkley was formed in would never support such a broad expanse. The breakdown collapse was apparently quite old. It appeared that the floodwaters of the large river forming the passage had either dissolved or transported downstream much of the collapse making the open area of the room abnormally large and open. The room was about 250-300 feet long and averaged close to 100 feet wide. The ceiling height rose to 50-60 feet above the stream.
They all agreed that it was worthy of being named “The McLain Mountain Room” in honor of ISS stalwart Tim McLain who died of a heart attack last November in another part of the cave. They also decided the passage should called “The McLain River”. Tim would have been proud!
They knew their time was limited so they hurried their survey up the river for nearly another half mile where the passage opened up into another large room with a somewhat larger mountain of rock.
It was getting late so they decided this would be a good place to stop work and pick up the survey on the next trip. Several decided to recon ahead a short distance from the upstream side of the room. As they climbed down the backside, they saw themselves peering down into a beautiful clear rise pool. The McLain River passage flowed up and out of a 12-foot in diameter deep blue-green pool. Only divers would be able to follow the river further upstream. Chris Parks, one of Indiana’s few cave divers, was on the trip so he plunged into the water to see what the dimensions of underwater conduit might be. He thought the prospects for diving the rise of the McLain appeared excellent. The problem was, they were 6+ hours from the nearest entrance beyond 3,000 feet of crawling passage. No group of Sherpa’s was going to drag diving gear that far into the cave and back out. Any dive would have to wait until a new entrance was found closer or drilled into the big borehole.
Reluctantly, one team agreed to place a few more survey shots to finish the survey to the actual sump. Then they started the long slog out. It would be after 3 am Sunday morning before the last cavers emerged from the Miller’s entrance after a 17+ hour trip. They had surveyed over 7,200 feet of virgin passage bringing the length of the Binkley Cave system to 40.61 miles. They are now only a couple hundred feet from 8th place on the US Long Cave List.
Lots of potential remains in the area. Explorers saw several large side passages leading of into darkness the river downstream from where they entered has barely been explored. The strong breeze flowing in the McLain River passage indicates there is much more cave to be found.