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California Gold Country Caverns

April 18 2017

A few of us at are exploring a locations in the Sierra Nevada foothills in Jackson County, California - and sending the first Trident ROV off the production line deep into flooded caverns. First location is a flooded / abandoned gold mine. The second is a deep, expansive cave in the same region as the mine. The third location will be improvised.

April 18 2017


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Debriefing Stage

We may visit mine again in future when some ROV issues are worked out and push the depth limits of this flooded hole in the ground. Until further notice there are no plans however.

Mission Underway

May 27, 2017

Second visit to Kennedy mine. Having visited 4 weeks prior with some success, and arguably more failure, we were better prepared this time.

This trip was a day trip, pretty focused on just the mine itself unlike our last visit. One considerable difference to note, is that in the 4 week span between these dives, Trident software, firmware, as well as some key pieces of hardware had been drastically improved upon. We had no technical issues on this dive.

This being the case, and our desire for positive results having had some time to ferment, we really effectively executed on a quick and efficient deployment of the ROV. Less than 10 minutes after pulling up in our car, we were a few meters deep. It was such a good feeling.

The water visibility was not as good on this second dive. We got about 25 meters deep, and determined that it would be best if we come back when visibility had improved to go deeper. There seemed to be a few timbers and logs, and the last thing we wanted was to get tangled up down there. The prototype units are very expensive, and we didn't want to lose one in such a clumsy way.

The uncut version: The honest way that it actually unfolded, I (Nima) was a tad bit irate as I wanted to go deeper than 25 meters, especially having driven a few hours to be out there in Jackson in the first place. My colleague was hesitant and more conservative than I with regards to pushing our limits and takings risks, and in the name of diplomacy we concluded the dive to avoid a quarrel out in the field. The bottom of this shaft is still a complete mystery. We do know what the walls look like.

There will be a dive video and many photos coming soon. Don't have the external hard drive at the time of this post. First and foremost I am an adventurer. The storytelling part of it usually trails behind, especially given how demanding my calendar is during this era of life.

This region is teeming with caves, caverns and flooded mines. We have a personal resource that has agreed to show us around, and we will be back sometime in the future. Hopefully with spelunking gear!

I'd be a liar if I claimed that I post expedition logs on here promptly after trips. Nevertheless, here is a run-down of our trip down the mine-shaft.

There were two separate trips, about 4 weeks apart from each other.

April 21, 2017:

First time visiting Kennedy mine. Quick tour of the premises, which consisted of all the old buildings and processing facilities used until 1946 or so. From mid-1940's through mid 2000's, the premises have been vacant, with much of the old equipment, office documents, etc left completely intact and unmoved. Many of the flooded mines in the area became popular destinations for local residents and workers to dump their garbage into what seemed to them to be a blackhole, a void. Only in the mid-2000's was it fenced off for concern of safety. This means that there is 60+ years of unknown activity. We were mentally prepared to find something grisly after being told this.

We were escorted to the big flooded hole beneath the mine's head frame (tall building from which the mine's elevator is deployed). Short walk down. Very much a neglected hole. Until we contacted them with interest in the flooded cavern the site operators had hardly paid any attention to it, if at all.

We deployed our Trident ROV prototype unit. We had some issues this first dive. While it initially worked out alright, within 20 minutes we were having connectivity issues, camera stream dropping, and video files being lost. We had about 30-40 minutes of diving within 5 meters. on top of all that, we had gotten the tether wedged in a crack in a redwood timber that had floated up to the surface of the shaft from the bottom. It was quite precarious, as the tether had to be wrangled out from the crack it was stuck in with a 6 meter long piece of wood, while standing on a rusty cat-walk over the shaft.

This first dive was honestly pretty underwhelming. We wrapped up our dive, cleaned up, gave the ROV a bleach-bath to kill anything that may have gotten itself stuck to the ROV, and went on to the rest our day. We had tried to dive Trident in Black Chasm cave, which is a national monument, however is it privately operated and the gift shop manager didn't seem to be moved by our proposition to investigate the bottom of their cave for them via robot. Well, they actually were interested however they insisted we rent the entire cave out for $400 / hour. We ended up taking the tour anyway, which was bittersweet because the cave was incredible but our real intentions were stifled by lust for profit. Slept at a nearby campground that night.

Next day after having a privately operated natural feature not be available to explore, we were intent on finding someone local who could tell us where some NON-privately operated caves might be. So we went to a gold mining museum, where this gentleman (whose name I cannot recall) fully dressed in gold miner regalia was exactly the person we were hoping to find. Having been in the region since the 1970's, after our inquiry he proceeded to tell us of all the caves, quarries, other abandoned mines, where he personally goes to look for gold, where he goes to smoke joints and where the local freemasons meet weekly. My notebook has at least 3 pages of information acquired from our new friend. Got his phone number - landline only, as he refuses to adopt cellular technology. I applaud him being steadfast in his own way of life.

We then determined that this trip was more of a reconnaissance mission and that it was to be continued.

Preparation Stage

We packed up our gear and did a full equipment test, made sure everything was charged on Thursday night, Apr 20. As we were driving to the dive location, and knew there wasn't going to be a huge amount of hiking involved, we had the luxury of packing excess.

Our packing list included the following (excluding camping gear and food, which was an afterthought):

  • Trident ROV
  • Laptop computer
  • Computer and ROV charger
  • Game controller
  • Lighing rigs (we built 4 of them using ROV battery tubes and external light cubes)
  • Multiple battery sets
  • Headlamps
  • Spool of string
  • Headlamps
  • Camera for still shots
  • Tripod
  • x2 GoPro cameras for video
  • Pelican case full of bleach-solution water (for cleaning equipment exposed to water with unknown qualities)
  • Glass vial (for taking a water sample / trophy)
  • Basic electronics tool kit (multimeter, battery-powered soldering iron, needle nose pliers)
  • Gloves and respirators
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Expedition Background

Who knows why we get the urge to explore, or why we perpetually expand upon what is accessible. The long-pondered allure of subterranean waterways came to mind once again, as it has for years.

On Friday, April 21- A small team of engineers, ROV enthusiasts and explorers are taking an OpenROV Trident to a flooded and shut down mine shaft in Jackson, California. Nobody on this trip has sent an ROV into a labyrinth of tunnels before. The excitement is childlike.

Located at the foothills of the Sierra Nevada Mts, Kennedy Goldmine is tapped into the 'Mother Lode', a mineral-intense region from 1.5 to 6 kilometres (0.93 to 3.73 mi) wide and 190 kilometres (120 mi) long, extending from El Dorado County on the north, south to Mariposa County.

I called and talked to the operator of the historic landmark: It is currently flooded all the way up to its entryway, at ground level. Operational gold mine between 1848 and 1942. During wartime conservation the gov't mandated all single-ore mines shut down to conserve labor for more productive multi-ore mines. While it was running, they had to pump out 1,000 gallons per hour, 24/7 to keep the shafts from flooding. Maximum depth is 1500 meters. Nothing is known of its layout, there are no records available that would help us extrapolate what it is like inside. Total mine output was 1.7 million ounces of gold. Above the mine, they used to smelt gold ore into bars, that would be transported to San Francisco via Wells Fargo.

Using the ROV, we are going to try to get a good sense of the layout of the tunnels. The goal of this dive beyond scratching a curious itch is to learn how to best navigate in an underwater labyrinth environment. The tunnels are [assumed] very small, not always level or straight, with many forks and branches. This is going to be a good challenge. Using visual cues from the camera feed, depth and gyro position, we are going to employ our geospatial visualization skills to form an idea of a day in the life of the working mine.

This first excursion will likely only take up the first half of the day, leaving plenty of energy left to explore other caves in the region, of which there are plenty. One nearby cave with an underground lake, that had inspired a great deal of ambition and excitement around it, is run by a private tour company that requires we rent the entire premises to explore its waters, which is unfortunately beyond our means. It is part of the Calaveras cave network - Black Chasm Cave, California Cavern and Moaning Cavern.

As none of us on this trip are acquainted with the cavernous foothills, and non-commercial cave openings are not easy to find online, we may simply ask locals where we can find what we are looking for - which is a deep mysterious hole, preferably with water.

Part 1: Mine shaft -> Planned out very concisely, ready to execute.

Part 2: We don't know yet. We will most likely end up just taking a regular cave tour (which definitely won't suck) and hoping that they will let us carry that Pelican case in after all.

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