BY ULF DANNENBERG

 

The memory is still very clear. When I was a kid about 9 years old, we played Cowboys and Indians in the ruins of bombed-out Hamburg in postwar Germany. We kids consumed the mandatory literature about Billy the Kid, the Lone Ranger, and the exploring of America’s Wild West. Sometimes we read with a flashlight under the bedspread, reading until deep into the night.

These stories had such an impact on me that my fantasies about America nearly became an obsession. The dream that formed in my mind at that time came true in 1965.

My first time in America and I was hooked. I spent the second half of the 60’s in Hollywood, California, became part of the Hippie crowd with all its good and bad things. While I survived all of that in pretty good shape, I was hopelessly spoiled. Unable to go back to the 9-to-5 routine in Germany, I became a world traveler with odd job opportunities that lay left and right along my way of life.

Mining for gold was one of the more adventurous tasks I took on in ’81. The last frontier–Alaska was calling me from afar. My old VW camper was shipped from Germany to Houston, Texas; and after four weeks, I picked it up and was on my way. I made a stop in Phoenix, Arizona and bought a 2″ dredge, together with all the other mining paraphernalia that was needed

The distance between Los Angeles and Fairbanks on a small scale map doesn’t look very far–but drive it and you’ll be surprised. It took me about a week to get there. Fantastic landscape and thrilling wildlife throughout the trip. Breathtaking, awesome, unbelievable, hard to put into words!!

My first mining experience was a bad one. Everywhere I went along the rivers and creeks, I saw huge signs with KEEP OUT, ACTIVE MINING CLAIM. After two days of looking, I ended up along the old Steese Highway some 30 miles out of Fairbanks, working the tailings of one of the old bucket-line dredges they used in the past. The outside temperature was 75 degrees by the end of June; but when I put my hands into the water -brrr – I pulled them out and checked for frostbite. The water temperature was barely above the freezing point, and it took all the fun out of the gold mining.

Disappointed, I left Alaska and went south. A short stop over in Auburn, California along the North Fork of the American River looked much more promising. I recovered two ounces of gold in six weeks – not bad for a beginner with my little dredge.

When I went back to Germany (I had run out of cash), I decided to become a belt-maker. For the next five years, I worked in Spain on the lovely island of Ibiza, making and selling my designer-belts with great success. In 1987, I tired and retired. I had enough funds to be on the road again for the rest of my life and could do whatever I wanted.

Shortly after my retirement, in Germany, I saw a TV special about the New 49’ers Gold Prospecting Association in Happy Camp, California. The impression I got was sound and solid. I was off to California in a jiffy and arrived in Happy Camp in July of 1989. I joined the New 49’ers and scouted out the miles and miles of claims along the Klamath River.

Because of my busted eardrum, deep diving was out of the question. I could only operate a gold dredge in shallow water, hoping to find bedrock in no more depth than five feet. For the rest of the summer, I was finding enough gold to show the folks back home.

I especially like the fringe benefits of mining, like the unspoiled nature, the abundance of wildlife, and the friendly, helpful people. That was something I had never experienced before. Socializing at the Saturday potlucks with raffles, stories and games, made my stay a happy one.

I have returned to Happy Camp multiple times in the preceding years. I can think of no other place where there is more active small-scale mining going on, and so many other people who have similar interests.
The very valuable training and assistance I received from the New 49’ers was thorough and founded on many years of experience. All I can say is – thank you – you’ve been a great help – and I’ll be back!

 

Let me end with a little poem that just crossed my mind:

The summer is gone,
Now is September,
And the end of your vacation is near.
You had a good time,
And you’ll remember –
Back home – frustrations you fear.
Then think of the Klamath,
Its gold and its fame,
Make plans for the upcoming year.
And maybe – who knows –
I’ll be seeing you again,
‘Cause part of my heart is left here.

 

It is getting pretty close to dredging time, and if you are anything like me and the many other dredgers I know, you are probably just itching to get started.

My partners and I, from past experience, now spend the necessary time and energy, before the dredging season starts, in getting all of our equipment repaired-to avoid the otherwise often confrontations with Murphy’s Law.

Some of the standard things we go through are as follows:

Engine and Pump: We always replace the spark plug, motor oil, points and condenser and air filter at the beginning of every season. We also pull the pump impeller to make sure it is not worn or damaged, and to make sure nothing is lodged in it. And we check the pump seal and replace it if it looks the least bit worn.

Air Compressor System: All of the compressors I have seen on gold dredges have reed valves. These are stainless steel plates which allow air to only flow one way through a chamber. These reed valves ought to be cleaned, polished and straightened at the beginning of every season. Some compressors have rubber diaphragms and some have piston rings. These ought to be checked and replaced if necessary. Rebuild kits are generally available for each type of compressor-usually from your local prospecting equipment dealer.

We always open up our regulators and blow them out with compressed air. You will want to check to make sure there are no holes in the rubber diaphragm, and make sure the rubber exhaust seal is working properly. If you have problems with water getting inside your regulator, it is almost always because of a worn out rubber exhaust valve. These are easy to obtain and replace.

It is especially important to open up and clean any check (one-way flow) valves in the air system. We also always soak our air lines in a very mild bleach-water solution before starting a season. We let the airline sink in a tub of the solution to allow the bleach to kill off any fungus which has grown inside the airline. This is to avoid potential respiratory problems from the fungus. The line needs to be thoroughly rinsed with fresh water afterwards.

We check all of our airlines and fittings to make sure everything is working properly-no leaks, and no weak connections!

We thoroughly clean out our air reserve tank to make sure there is no rust, fungus or other substances which could potentially cause problems.

Dredge (Structural): And, of course, we go over the sluice boxes, dredge frame and jets to make sure there are no holes, cracks or other structural problems. And if we find problems, we fix them on the spot. No need to wait until it becomes a more serious problem during the season.

We hit all of the steel with a wire brush and follow up with a fresh paint-job every spring. It’s nice to start the season off looking good!

We go through all of our rope and make sure all of the weak points are cut out and spliced back together, and all of the ends are spliced or melted so there are no frayed ends.

Diving Gear: We go through all of our diving gear, replacing anything that is worn out, patching holes in suits, etc. No need to be any colder than necessary during the early spring!

While fixing up the dredging equipment is not as good as using it, I personally gain a great deal of satisfaction getting it all prepared for the season. And, it’s always a good feeling when I do get out on the river when I have it all together the way it should be. And when “Mr. Murphy” comes knocking at my door, at least I know it wasn’t because I failed to plan ahead.

 

By Dave McCracken

It is common to find rich gold deposits in shallow streambed material out under the fast water where nobody has ever ventured before!

Dave Mack

Something we have known for quite some time is that pay-streaks, often very rich pay-streaks, exist in the fast water.

At first, this may seem contra­dictory to our general understanding that high-grade gold deposits form in areas of the waterway where the water slows down. However, we must keep in mind that pay-streaks are created during major floods. During a major flood, a sudden drop in the bedrock can cause a very good gold trap, like the riffles in a sluice box, but on a very large scale.

If you turn on a garden hose at slow speed, the fast-water area is found directly where the water flows out of the hose. But when you turn the water-pressure up, momentum forces the water farther out. This condition also occurs within the river during a major flood. Areas where the water runs fast during low-water periods are likely to be drop-zones for gold during high water. The heavy momentum/velocity area will be forced farther downstream, leaving a drop-zone for gold just below the bedrock drop. This explains why you can often find pay-streaks under rapids when the river is flowing at low-water levels. It also explains why you seldom find pay-streaks within the first slow-water area below a set of rapids when the river is running at low levels.

Another reason why you are likely to find gold in fast water is because dredging in fast water is more difficult. Therefore, others are less likely to have mined there before you – including the old-timers. For this reason, fast-water areas can often be virgin territory — meaning places where the original streambed material remains in place from thousands of years of natural geologic activity.

  

What exactly is “fast water?” This depends upon each individual person’s viewpoint. It is primarily a matter of the diver’s comfort level. To some people, if the water is moving at all, it is already too fast to dredge. Other dredgers are able to dredge in water moving so fast that the air bubbles created by the turbulence eliminate all visibility. After diving in really turbulent water, a person’s equilibrium can become so disoriented that he/she can hardly stand up without weaving around, as if intoxicated.

Several years ago, a friend and I were operating a five-inch dredge in some very fast, shallow water. Because of the extreme turbulence, one of us would work the nozzle, while the other would hold onto the dredge to keep it from flipping over. The water was so swift that my friend was swept out of the dredge hole time after time. Once, he was carried away so fast, he didn’t have time to untangle himself from his air line before he reached the end of it. The air line was tangled around his neck! There he was, flopping around in the current, like a flag snapping in a stiff breeze, tethered by the air line around his neck and struggling, unsuccessfully, to regain his footing in three feet of water. After he got safely to the bank, we both laughed so hard that tears were streaming down our faces. That was emotional stress blowing off. Fifteen minutes later, I was the one bouncing in the current behind the dredge, facing backwards at the end of an air line caught between my legs. Needless to say, my friend thought this was pretty funny, too! Dredging in fast water can be fun and exciting (not to mention the gold you can find). But, you must be aware of and prepared for the dangers involved. There is very little margin for error if you get into a situation that is beyond your ability to manage. We all have our limits!

SAFETY

Notwithstanding all the excitement and gold, safety should always be the most important personal consideration. You are the one out there in the field with the responsibility for using good judgment about what you can safely do, without cutting your margin for error too close. The river does not have any sympathy for people who “get in over their heads.” I’ve known several dredgers who lost their lives by over-stepping their personal safety boundaries. It only takes a single mistake. The rest can happen very quickly. Even I have come close to drowning on more than one occasion! All the gold in the world is not worth dying over!

For the sake of safety, it makes good sense for you to not dredge in water that is faster than you are comfortable with. You will have to decide what that is. It is best to practice first in slower water, to gain experience and confidence.

One important thing you should remember about working underwater: Everything may be calm and under control right now; but five seconds later, you can find yourself in the most life-threatening emergency you have ever experienced! This is even true in slow water. But, fast water gives you less margin for safety if you make an error or anything goes wrong. You should not dredge in fast water if you are unable to control the various problem-situations that could develop. You need to anticipate each problem that could possibly arise and work out your response, in advance.

Contrary to what many people believe, being swept down river by the current is not the major concern. This is a normal-happening in fast-water dredging. As long as you have your mask clear and your regulator in your mouth, being swept down river by the current is generally no big deal. That is, of course, unless you are dredging directly above a set of falls or extremely fast water.

In most cases, the “fast water” you are in is not a steady flow of current. It is usually turbulent, varying in direction and intensity. A swirl can hit you from the side and knock you off balance. Or, sometimes it can even hit you from underneath and lift you out of the dredge-hole and into the faster flow. If you get swept down river in fast water, you usually just need to grab hold of the river bottom and work your way over to the slower water, nearer to the stream bank. This movement is normally best-done by continuing to face upstream, into the current, while you point your head and upper-body towards the river-bottom. That posture will nearly always drive you to the bottom where you can get a handhold on rocks or cobbles to anchor yourself down. Then, you can work your way upstream, through the more slack current near the stream bank, and back out to your work-site again. This is all pretty routine in fast-water dredging.

Getting a hole started is one of the most difficult challenges in fast-water dredging. Once you even get just a small hole started into the surface of the streambed, the suction nozzle in the hole can serve as an anchor to help hold you there against the current. There will also be several cobbles behind you to use as footholds, which also make it easier to hold a position there. After the hole has been expanded to the point where you can get at least part of your body inside, you will find significant relief from the effects of the current’s flow. But, it can sometimes be a real challenge until you do get to that point! At times, you may find it necessary to start your hole in slower water, then gradually work your way out into the faster current.

One of the main concerns when dredging in fast water is having your mask and/or your regulator swept or knocked off your face. This situation is one that can cause a person to panic, especially when both mask (vision) and regulator (air) are lost at the same time.

PANIC

There is not a single a person among us who won’t panic, given the right (wrong) situation. People who say they will never panic under any circumstances are just not facing reality and, obviously, have never come close to drowning. I believe it is better to understand and acknowledge your limitations before you get into trouble. The closer you cut your safety margin on safety issues, the more aware of your limitations you should be. And, the more important it is to plan in advance how you will react to certain types of emergencies. It is already too late to make such plans the moment something bad happens!

For me, it takes a lot of personal discipline to stay under control when an unexpected rush of turbulent water jerks my mask off and drags me, blindly and chaotically, down river. This has happened to me on several occasions. I know that under those circumstances, it would not take much more confusion (e.g., air line getting snagged, my body being banged against something, losing my balance, getting a breath full of water from my regulator, etc…) for me to totally lose control and freak out (panic).

I have worked with several guys who have a higher tolerance from panic in the water than I do. And, I know others who feel panicky as soon as they put their heads underwater, even under perfectly-controlled conditions. We are all different, and we each have our own particular point at which we will panic in different circumstances. Everyone has a limit. These limits can actually change from day-to-day, depending upon what other things are happening in our lives. It is better that we not delude ourselves about this. If you allow yourself to get overly-confident, and continually put yourself into situations that can take you beyond your limit, sooner or later you will almost-certainly find yourself tested in a life or death situation.

Panic is a survival-mechanism that takes over when your mind is convinced that your life is in grave danger. At this point, your animal instincts take charge and deprive your intellect of the ability to reason things out. Panic tells you that there is no time left, that you are literally fighting for life just before unconsciousness. The situation demands that you spend your last/maximum physical effort to remove yourself from the danger that is about to mortally injure you or cause you to lose your life. Panic is a horrible, terrifying, and, sometimes, embarrassing experience that happens when your normal, rational self loses control, and the animal-part of you takes over.

There are milder versions of panic. Someone might “panic” and do something silly or foolish in a business or a personal setting. That is not the type of panic that I am talking about here. I’m talking about the raw physical panic that grips you at the moment you realize you may be at the point of losing your life.

There is always a chance of getting into serious trouble any time you are working under the water. Trouble underwater is serious because humans cannot breathe water. There is no margin. You are either breathing air or you are not. It is an immediate emergency when there is no air. Such emergencies can happen in a split second, any time you are in a dredging environment.

TAKING EXTRA PRECAUTIONS

Other types of underwater vulnerabilities are especially present during fast-water dredging activity. Some of this vulnerability is because it is sometimes necessary to weigh yourself down more-heavily with lead weights to stay on the river bottom. Extra weight is needed to give you the necessary stability and leverage to control the suction hose and nozzle and to move rocks and obstacles out of your way. The demands of dredging activity require divers to be so heavily weighted down, that it is impossible to swim at the surface without first discarding the weights that hold you to the bottom.

One of the most serious dangers to a dredger is the possibility of being pinned to the bottom by a heavy rock or boulder. All of the oversized rocks that cannot be sucked through the dredge nozzle must be moved out of the hole by hand or with the use of winching equipment. When undercutting the streambed, or taking apart the dredge hole, there is the possibility of larger rocks rolling in on top of you. This possibility increases when you are working in turbulent, fast water. The erratic changes in the pressure that the water exerts on the exposed streambed material, inside and around the dredge-hole, can cause boulders to loosen up and roll into the hole. These same boulders, if located in a streambed where the water is running more slowly, might not loosen up the same way, if at all. For this reason, a fast-water dredger must take extra precautions to remove all larger-sized rocks when they are exposed. One of our mottos is: “You have to get the boulders before they have a chance to get you!”

When working in fast water, all of your normal safety precautions, preventative maintenance measures, and common sense instincts must be scrupulously observed. Fast water may be thought of as a liquid flow of energy that is constantly challenging you and your equipment. Murphy’s Law (“anything that can go wrong, will go wrong”) is always at work in fast water. It is hard enough to deal with the things that you cannot anticipate will happen. You will have enough of these as it is. But, if you neglect to take action with respect to those things that you can reasonably expect to go wrong, you will almost certainly fail in your efforts to dredge in fast water. If it is wrong, fix it now, before it gets worse!

 

OPERATIONAL CONSIDERATIONS

My dredging partners and I have found that it is physically possible to dredge in water that is too fast for the safety of our dredge — even the kind of dredge that has been designed for fast water. Therefore, the need to operate in an environment that is safe for your dredge is one of the major limiting factors in fast-water dredging.

Most fast-water dredgers add more flotation to their dredge platforms to give more stability. This can be done in different ways, including additional pontoons, inflated tire inner tubes, PVC pipe material, Styrofoam, etc.

One of the main considerations when adding more flotation to a dredge is to avoid increasing the drag against the current. Additional drag causes problems in two ways:

1) The fast-water current puts more strain on your dredge, frame, and tie-off lines.

2) More importantly, the surface-tension caused by all that additional water dragging around the dredge makes it difficult to work near the dredge when you are in the water (which can be a particular problem when you are trying to knock out plug-ups from the suction hose near the dredge).

Another goal when adding flotation is to keep the floats as narrow as possible. A wide set of floats is more likely to be tossed or dragged around by the turbulent flow of fast water.

Generally, when working in fast water, I try to find a location for the dredge where the water is a bit slower, just next to the fast water where I plan to work. This way, I can enter the river in slower water and work my way out underneath the faster water, adding suction hose as necessary.

Otherwise, if we position the dredge directly in the fast water, it will become necessary for the divers to contend with fast water when entering the water from the dredge. This can be done; but it makes the operation more difficult – especially, when the dredgers need to climb back onto the dredge.

Also, the buildup of cobbles and tailings near the dredge can add to the surface-tension and create an even faster current flow under and around the dredge.

When you are set up with the dredge positioned off to the side in some pocket of slower water, your suction hose will be running perpendicular, at least to some degree, to the flow of the fast water. That much hose exposed broadside to the current creates enormous drag, which can cause the suction hose to kink usually within a foot or so of where it attaches to your power jet. Hose-kinks will cause continuous plug-up problems, so they must be avoided. Therefore, you may find it necessary to disconnect the suction hose and cut off the section that has been kinked. However, you cannot shorten your suction hose very much before you lose the amount of operational flexibility you need for freedom of movement while dredging.

Suction-hose kinks can usually be avoided by setting up a special harness to support the hose in fast water. This is often done by rigging one or two extra ropes down from your main tie-off line. The ropes are fastened to the suction hose at points which will allow the hose to be flexed back by the current, but not to the critical kinking point. You must allow the hose to flex back. It is the bend in the suction hose which allows you the movement to expand the size of your dredge hole.

It is best, when rigging a fast-water harness, to rig it in conjunction with your main dredge tie-off line. This way, the entire dredge and suction-hose harness will move together, as a unit, when you need to move the equipment forward as your dredge-hole progresses.

Suction hose support booms are standard equipment on the commercial Pro-Mack dredges.

Larger and commercial dredges may be equipped with booms, which can be extended out in front and used to secure a suction-hose safety harness. In this manner, when the dredge moves forward, the suction-hose safety harness moves with it, as in the situation above.

Another concern in fast-water dredging is to keep your suction nozzle and hose from being swept out of your dredge hole. Sometimes, the current will put so much drag on the suction hose that it takes all of your strength and energy to get any nozzle-work done at all! In such a case, you can relieve the main strain of the drag by tying a section of the suction hose to a large rock at the rear of the dredge hole or some other anchor point further upstream. When doing this, always leave enough slack in the hose to allow you to move the suction nozzle forward as your dredge-hole progresses. Also, be sure to remember to untie the suction hose from the river-bottom before you move the dredge. Otherwise, you can damage the hose by causing kinks in the middle! If you kink the hose in the middle, you will have to replace the hose!

We have also worked out a way to extend the suction hose, swing it out on a pendulum line, and anchor it in place using a spare weight belt.  This method nearly eliminates all of the hose drag for the person managing the nozzle.

When you take a lunch-break or knock off for the day, you can anchor your hose and nozzle by either piling rocks on the suction nozzle or by tying the nozzle to a large rock in the bottom of the dredge hole. It is not any fun to start a production-dive by having to work against the current to get your suction hose back up into your dredge hole, because the fast water blew it out after your previous dive. But, of course, all fast-water dredgers get many chances to experience this. It is a normal part of the routine!

One important safety point: When using ropes underwater, it is a bad idea to use any more than is absolutely necessary. A lose rope is poison to divers underwater, especially in swift water! Always cut off any excess rope or pile rocks on top to hold it down. If there is a length of loose rope flopping around in the current, something (like your air line) always seems to get tangled in it. Loose rope under water is dangerous!

Your air line can be another source of problems when dredging in fast water. Always be sure to get all the loops out of your air line before starting your dive. Otherwise, the current can pull these loops into kinks, which can immediately cut off your air supply. Not fun!

When you turn around in your dredge hole to roll boulders, toss cobbles, or do any of the many other things associated with production dredging or sampling, get into the habit of exactly reversing your turn when you face forward again (turning back counterclockwise is “cancelled out” by turning forward clockwise). This practice will help prevent you from putting lots of loops in your air line during the course of the dive. Each loop is a potential kink that can cut off your air supply in fast water. Each loop also increases the amount of drag being brought to bear on your air line in fast water.

If you should get a kink in your air line that cuts off your air supply, you can usually get some immediate relief by pulling your air line in toward your body and letting it go. When you let it go, the pressure is temporarily removed from the kink, and you can usually get a single breath of air. I always try this once, quickly, when my own air is suddenly cut off. If that does not give me immediate relief, I crawl right over to the surface so I can properly correct the problem.

If you are experiencing any difficulty with a kinking air line, your best course of action is to immediately remove every single loop in the line. Getting rid of the loops will require you to rotate yourself in circles, going in the appropriate direction, until the air line is straight again.

Several years ago, I was dredging in fast water with a guy who had to repeatedly dive out of our dredge hole because of a kinking air line. After about the fifth time, I suggested that he take the time to straighten out his air line to fix this problem. This remedy only worked for a short time, because he had developed the habit of turning around and around in the dredge hole as he was moving rocks, which just created more and more loops in his line. Fifteen minutes later, he was diving right back out of the dredge hole again.

These days, you can buy a heavier-type of “safety” airline that will prevent kinking in all but the swiftest of fast water. I recommend this heavier air line to anyone who plans to dredge in swift current.

By the way, your air line is also your direct connection to the dredge and to safety. When you connect your air line to the dredge, even in slow water, it should be wrapped around the dredge frame several times before being attached to the air fitting on the dredge. Most air fittings are made of brass. If you should need to use your air line to pull yourself to the dredge in an emergency, it is better that you not have to depend solely upon the strength of a brass fitting!

Nearly all experienced dredgers are aware of the fact that their air lines are an extension of themselves while under water. Especially in fast water, it is very important that you not allow your air line to tangle around parts of the dredge, underwater obstacles, and/or the air lines of other divers in the dredge hole. If you cross over the top of another diver’s air line, keep that in mind, so you will be sure to cross back over it again when you return. Each time you go to the surface, to remove a plug-up or for whatever reason, take a moment to untangle your line from anything it may have wrapped around. As a standard practice, all dredgers should always untangle your air lines each time you return to the surface for any reason. I personally never end a dive without first freeing my airline completely, so it will be ready for the next dive.

One of the persistent problems of dredging in fast water is the heavy drag on your air line. This can normally be solved by pulling some slack-line into the dredge hole and anchoring it against the current with a single cobble placed on top. This will allow some slack air line between you and the cobble. You want to be sure that your cobble-anchor is not so large that you cannot quickly free your air line in an emergency. Also, when you leave the dredge hole, don’t forget to first disconnect your air line from your anchor.

Full face masks are generally not well-suited for diving in swift water. Since they are larger, with substantially more surface area, they are more likely to get accidentally dislodged from your face. This can happen when the mask is bumped on another diver, or an obstacle, or when turbulent water catches it, especially from the side. To further complicate matters, when a full face mask fills with water, the regulator usually does as well. Having to clear the water out of your mask and regulator at the same time can be more difficult and contribute to a panic situation. I personally find that I am more prone to feeling panicky when something goes wrong inside of a full face mask. If your reactions are similar to mine, you may want to avoid using a full face mask in fast water.

DO’S AND DON’TS!

In any kind of a dredging operation, fast or slow water, it is wise to become familiar with your surroundings as your first priority. Before you begin work, make sure you know the easiest and most direct route to crawl over to the surface in the case of an emergency. Don’t wait until an emergency happens before you think about this. By then, it is too late!

Here is some really good advice: Do not tie yourself into a dredge hole in fast water to keep from being swept down river. It is bad enough having a heavy load of lead attached to your body! If you have to tie something, tie the suction nozzle from a point further up river (with no loose rope flapping in your face). Then hold onto the nozzle to keep yourself steady and in place, while you get the hole started. Get rid of the rope as soon as you have a hole started!

Generally, the most effective way to maintain your position in fast water is to streamline your body properly, with your head and chest close to the river-bottom and your rear-end slightly elevated. This posture allows the water-flow to push you down, toward the bottom, so you can get a better footing. Begin creating your dredge hole as soon as you can. The hole will help anchor you in place. The larger you dredge the hole, the easier it gets.

Some dredgers try to solve their stability problem by putting a lot more lead on their weight belts. Sometimes in turbulent water, more lead can be a help. But, be extra careful when walking out of the water on the slippery bottom, so you don’t overload your ankles and knees and injure yourself.

Most importantly, it is very unwise to solve your fast-water buoyancy/stability problem by adding a bunch of additional weight belts. Take it from me; it is hard enough to get one belt off in a hurry, without compounding the emergency with three of them! Sometimes, you cannot manage the needed extra weight without 2 weight belts, but you must understand that a second belt substantially reduces safety margin in an emergency. Additional belts tend to shift around so that the quick releases are in different places, often behind you where it is more difficult to release them during an emergency. Difficulty in finding them in an emergency can contribute to a panic situation and put your life at risk.

Whatever else you do, early in your dredging career, it is wise to discipline yourself to never try and swim for the surface in an emergency while wearing your heavy weight belt. It just doesn’t work! In a panic situation, your body will want to go immediately for the surface instead of removing the weight belt. I have personally saved two people from drowning who were trying to ”swim for it” with their weight belts on. By the time they realized swimming was not going to work, they were in too much trouble (panic) to get their own belts off!

This does not mean you can’t get a good footing on the bottom and jump up to the surface for one quick breath of air. You can do that in an emergency, as long as the water is not too deep or fast. But, if you cannot crawl over to the surface quickly, your first priority should always be to get the lead weights off as soon as possible.

Keep in mind that you usually cannot see the quick-release buckle on your weight belt while underwater. This is because your face mask blocks your vision at that angle. So, it is important to practice locating the quick-release buckle by feeling for it. It is also very important to keep your belt from shifting around, so that the buckle always remains directly on the front of your body. One of the problems we already noted when wearing more than one belt, is that the top one tends to shift around. There is not much you can do about that. So with two belts, you should be prepared to find the top buckle behind your body!

You may also find that it is better to first remove your work glove before trying to release your buckle in an emergency. When I get in trouble, the first thing I do is get rid of the glove on my right hand!

These are all things you must be able to do quickly and instinctively before venturing into fast water. A wise skydiver would never jump out of an airplane without first receiving enough practice and instruction in how to find his rip cord. Similarly, a dredger’s life should be just as well protected by having a confident ability to release your weight belt quickly in an emergency.

Some of the weight belts on the market also include a suspender harness. The only ones I recommend are the ones that have a quick-release, D-ring on one of the suspenders that allows the shoulder harness to come loose on one side when you release a single waist belt buckle. Otherwise, in an emergency, you may find it too difficult to get out of the suspenders, even if the waist belt is released.

All this advice is coming from a guy that has devoted a large part of my life living on the edge. You can sit there in the comfort of your computer reading this stuff and feel quite certain that you can manage any or all of these things if they should come to pass when you are out dredging. But when the severe emergency happens, you are not the same person. You are a maniac!

You should always keep an eye on your diving buddy while dredging in fast water. When we dive with multiple dredgers on an operation, it is standard policy for us all to keep track of each other. If one person needs to leave the dredge-hole or go to the surface for some reason, he always lets someone know he is leaving. Otherwise, when a diver suddenly disappears, we immediately go looking for him. A person in serious trouble underwater only has about 30 seconds to get it together. This is not much time. What good is diving with someone else for the sake of safely, if you are not paying attention to what is happening with him/her, especially in fast water where there is so very little margin for error? A tender, or anyone else resting at the water’s surface, should be paying close attention without distraction when there are dredgers down working in fast water.

If all of this has frightened you, that’s good! That means I have accomplished my goal of alerting you to the dangers inherent in fast-water dredging. Being alert to, and fearful of, those dangers is the starting-point for making your own preparations and contingency plans for dealing with them – before you start working in fast water.

What is fast water? It depends upon the individual. An experienced dredger might be much safer in a typhoon of fast, turbulent water, than an inexperienced person would be in slow, shallow water near the bank. The key for each person is to begin learning in a safe and comfortable environment, gain valuable experience over time, and never attempt to do anything that you cannot easily manage, with safety.

 

 

BY ROBERT MILES

“Whenever I need some money, I tell my wife Karolyn that I’m going down to the bank to get some…the river bank that is. And so far, my belief that the gold is there, combined with hard work and good fortune, has never let me down.” … Jim Britton

 

Jim Britton’s the kind of man who will tell you right off that he’s doing exactly what he’s always dreamed of doing — that’s mining for gold. And even if he’s not pulling gold at the level he’d really like to at a particular point in time, he’s quick to say, “I’d rather be here beside the river enjoying the looking and anticipating the discovery than living in the city and breathing all that pollution and just working at some regular job.

“I was introduced to the Gold Bug at a very early age,” he says with a warm smile that turns quickly into a grin and makes one think that he may be about to spin a yarn. “Probably when I was six or seven years old. Back then, all us kids would watch adventure movies. I was hooked on the ones that had anything to do with gold. Then as I grew up I started reading about the old 49ers, and I just couldn’t seem to find out enough about where they mined and the methods they would use. Still it wasn’t till a few years later when I was out on my own with a shovel and a pan that I really got the ‘gold bite’. It was near a little town called Quartsville, just outside of Sweet Home, Oregon, where I actually found my first gold — about 1/2 pennyweight, and I’ve never been the same since.

“I’ve always believed you’ve got to do your homework, and that includes a lot of research. And in those days I had just began to discover all about underwater dredging, and I figured that since panning for gold was giving me such a kick, I would pull more gold and have a lot more fun if I had a dredge. So I went out and bought myself a two-inch suction dredge, and within no time at all I was pulling two to three pennyweight a day and just having a great time.

“That was really just the beginning,” recalled Jim, “because within a short time I had run into another guy who let me spend some time on his five-inch dredge. After a half an hour of pulling gold with it, I just couldn’t go back to working with my little two-inch. That’s when I had to get my entire family gold bitten,” he reflected. “My dad and mom had always been really supportive of the things I tried to do, but this time they just couldn’t believe that you could really just go out and find gold. Like most people, they figured all the gold was already found. However, within a short time I had them out there with me on the river bank, and by just getting them exposed to the gold I was bringing up with my two-inch, they were gold bitten real hard. Then within a short time, the entire family, including my older brother, was mining with our new five-inch, and we were pulling more gold than any of us had ever seen at one time.”

Like most successful gold miners, Jim Britton has tried working at a number of different jobs, but he says he just can’t get the river and the gold out of his mind. “It’s the thing I love to do,” he reports, “and besides, where could I ever get a job that pays as well as gold mining and has as much job security? There’s been gold miners since the dawn of recorded time, and there probably always will be. Some days I’ll make as much as $800 or even more, and I’ll do it in four hours. Of course, you gotta do your homework, and you gotta pay your dues.”

Jim’s formula for success still begins with a gold pan. “Before I put my dredge into a spot, I’ll pan up and down the bank, usually on both sides of the river looking for the point where the river’s deposited the most color during high water. I’ll have picked a particular stretch to check out, either because my knowledge and experience of how the gold is carried and pay-streaks are formed tells me that here should be good, or because someone else had been working there and either couldn’t locate the pay-streak, or had wandered off the mark and had decided to move on to a different area. By using my gold pan, I can usually get a good idea of where the river is ‘willing to payoff’ or at least where the pay dirt has hit the bank, and there’s where I’ll put my dredge in. I’ll first punch my hole and pay very close attention to the different pay layers. A lot of times I’ll find that the gold is lying four to five feet above the bedrock, and if I’d continue on down I’d just be wasting a lot of time and energy. Other times the bedrock’s where it’s gonna be, so I just have to keep on punching down till I hit bottom, and then I’ll begin a cut straight across the river channel.”

Jim has worked a lot of different areas of the Pacific Northwest, basically following up the different strikes of the old 49ers. He says he’s hit most of the hot spots in eastern and southern Oregon as well as spots in Idaho and California. Right now he’s mining the Klamath River in northern California, using a customized six-inch with a Keene power train and sluice box that is mounted on an R & R Mining frame and float bag kit.

“When I first saw the Klamath it looked mighty big, but within three days from the time I launched my 5-inch, I was into the gold and had enough money to cover my expenses and meet the bills for the next couple of months. I’ve dived this river for two years on a commercial basis, even in the winter when the dredge was white with a layer of ground frost, and the water temperature was probably 45°. Last summer in just three weeks I pulled one and a half pounds of gold in an area we call Glory Hole.”

Jim is also quick to point out that while mining is right for him, it may not be right for everyone. A person’s got to work really hard and be mentally and financially able to stand the dry spells. “I’ve been able to make it work because I’ve got the full support of my wife Karolyn and our two daughters. Karolyn, who lives and works in Vancouver, Washington, makes the long trip up to the Klamath every two weeks, spending the weekend helping to tend the dredge, enjoying the beauty of the great outdoors, and picking nuggets out of the sluice box. My folks have also been behind us a hundred percent, spending ,time at the river as well.”

Everett Gene Britton, Jim’s father, who helped finance that first 5-inch dredge, remained an avid gold miner until his death early this spring, stating in no uncertain terms that some of his very best days were spent panning gold and tending dredge.

In the local area surrounding the Klamath, Jim Britton is known as a man who will lend a helping hand. The kind of person who will take time out of his own diving schedule to get a neophyte gold miner off to a little better start. And he’s an advocate of “miners helping miners” and the necessity of miners working and standing together to protect their rights as granted under the 1872 Mining Law.

“My life is gold,” he reports. “In fact whenever I’m back home and someone comes to visit, my wife will tell them not to mention gold, or I’ll never stop talking about it. I’ve even tried to stay away from the river and the dredge, but it’s in my blood, and I get withdrawal pains whenever I’m away from it. My life is like living an adventure, and if someone would offer me a job at say a $100,000 a year, I would just have to pass it up, because finding gold is what I love and it’s what I’m good at.”

 

BY MARCIE STUMPF/FOLEY

 

Bill StumpfMost miners have a season that is very special. Sometimes because they find a lot of gold, sometimes because of a very special nugget; but they all seem to have one year that stands apart from all the rest. We, too, have such a year, but not for any of the above reasons. Our year stands apart because it really put our love of mining to the test.

The year was 1979, and we were especially looking forward to it. We had a new motor- home; but more important to my husband, Bill, we were upgrading from a 2 1/2″ dredge to a brand new 4-incher. Our three teenage sons were staying home, and we were taking our first vacation alone, ever!

We tried to plan carefully, as usual; but due to our three sons, there was always an ever-present need to economize. We decided that we would carry our mining gear in our aluminum fishing boat on its trailer, which didn’t have really good tires. However, after looking them over, we decided they would make just one more trip. That was our first mistake.

Our second mistake was the date we picked to start our vacation. California was in the midst of a record heat wave, and we left home on the hottest day (anywhere in the State) in a decade. By late afternoon, heading up Interstate 5 near Red Bluff, the temperature was somewhere over 120 degrees. We were wilted; the left tire on the boat trailer had developed an alarming bulge; and the auto air-conditioning in our new motor-home had died. We pulled into a campground, showered, and collapsed under the rig’s air conditioner, too tired to even eat dinner.

A good night’s sleep helped, and we were at a tire store when they opened early the next morning. After they replaced the tire, we pulled out onto the main street and headed out of town-so we thought. We hadn’t gone a block when we heard a big “thunk!”, and our new tire went flying past us, up Main Street. I can still clearly see Bill slumping over the steering wheel, saying “Oh, no!..Oh, no!,” as cars and trucks swerved, trying to dodge the tire as it merrily sped down the street. It looked like something from the Keystone Kops ! Then, a glancing blow from a truck sent it spinning crazily off toward the sidewalk. And as I looked up, I saw that it was headed right for a beautiful little church with stained glass windows.

We could only watch and hold our breath as it jumped the curb, crossed the sidewalk, and started up the church steps. One big bounce, then two, and the next would send it over the top and right into the window! But the tire just didn’t have quite enough “oomph” to go over the top, and we gave a sigh of relief as it hit the edge of the top step to bounce back down and into the street where it finally came to rest.

Only then did we notice that traffic had completely stopped, and we had quite a large audience. Bill was really thrilled to have to get out and retrieve the tire and all the lug bolts, apologizing all along the way. Red Bluff was quite small, and the audience obliged by waiting and watching him.

The lug bolts were stripped, but he put it back together as best he could, and we made it back to the store. Bill had a few things to say the whole time he worked, but I wisely kept silent. In such a situation, I have found it is better to not even murmur sympathy.

Although they did not have what we needed to fix it, they managed to get it together well enough for us to limp along the shoulder to Redding, another 33 miles. There, they managed to make the necessary repairs, and Bill bought a replacement for the spare tire on the trailer.

By this time, we had lost what little coolness the early morning held, and we sped on our way in the heat. Our next stop, Yreka, came at about noon, and we quickly picked up groceries, gasoline and propane, and then headed on our way. About 15 miles further, we had to find a large open area back from the road to stop.

Our third mistake was in not making sure they did not overfill our propane tank. (We have found this is common, and can be very dangerous). By now, it was 114 degrees, and we were in the sun, of course. We gratefully climbed back into the rig to resume our journey. But unfortunately it was not for long. Soon, a passing motorist, by honking the horn and pointing back, signaled another problem. You guessed it! The other trailer tire was flat. There was no shade in sight, and I don’t exaggerate when I say that we sizzled each time we had to touch the hot metal of the boat to get what we needed. I stayed out to help as much as I could, but made sure I stayed out of the way, and behind Bill, in case he reached the stage of throwing things. He was seeing so much red by this time I was afraid he might not see me.

The tire-change went smoothly, however; and in another fifteen miles, we had reached our destination to join our friends, Ned and Dori. What a relief it was to relax in the shade, sip a cool drink, and visit.

When we’d finished our news, Ned told us theirs. They had made a deal for us to dredge on a private claim about 10 miles further up the mountain. We excitedly broke camp, and hauled everything up there, where we labored the rest of the day getting our rigs back into the thick trees, in the cool shade. We were going to be here a while, and we wanted it right.

There had been a cabin here at one time, and the cleared area where it had stood would be perfect for campfires at night. We also discovered, off a ways, a “Three- Holer .” For you city folks, that is an outhouse with three holes. Actually, I’d never heard of one, either. It had critters, and it was dirty; but was still sound. Dori and I decided we’d clean it up when we had time. That night, as we sat around a fire, the tension from our trip faded, and the wonderful peace that we always felt when we got away like this descended upon us. It was August, and the days were long. By bedtime, the guys had made plans to get going early in the morning, and be dredging by noon.

In the morning, Bill sprang from the bed, eager to get the day started. Unfortunately, his aim was off a little, and he smashed his knee into the cupboard next to the bed. Ignoring my offer of a band-aid, he quickly donned a pair of shorts and went out to get things ready. In an hour or so he was back. He had added a bee sting to his other knee, and a huge multi-colored goose egg to a shin. Now he was ready for band-aids and medicine.

After I’d done what I could, he put on his wetsuit. His fourth mistake was in not putting his wet suit on first thing in the morning. They are good protection! He then hobbled off to finish putting the dredges into the water with Ned’s help.

When they finished, we took a break for lunch; and as we finished, we had a visitor. It was the miner who had the next claim up the creek, and he was very nice about it, but…Ned and Bill had launched the dredges over the claim line. So they spent the rest of the day moving the dredges and setting up in a new location.

When we arose the next morning, Bill’s cut, sting, and goose egg were surrounded by rash and were inflamed. His fifth mistake was in not watching carefully enough for poison oak. From there, he proceeded right to his sixth mistake. He dredged anyway.

By the next morning it was obvious even to Bill that everything was infected, and his poison oak was rapidly spreading to cover his entire body. Reluctantly he stayed out of the water; we soaked and applied creams and ointments, as he stared at it all, willing it to go away.

Despite all of our efforts, Bill looked much worse the following day, and we were growing concerned. He still refused to see a doctor. Our seventh mistake was to use band-aids and tape, which Bill has always been allergic to. As I tried to remove them to put fresh ones on, each small tug of the tape caused Bill to say “~UGH!!!” The sound was approximately equivalent to the ones they make in a movie when having a leg sawn off without anesthetic. No matter how hard I tried to be careful, each tug brought forth another “~UGH!!!”. To make matters worse, I soon had tears flowing freely from laughing so hard.

Ned and Dori came running to see what had happened now, and when I answered the door with tears running, they were really concerned. As I tried to explain, they became very confused, since Bill had a huge scowl, and was at the same time telling them about the cruel and inhuman torture I was putting him through. Finally, I removed just a small piece to show them (and to shut Bill up), and his words changed to “~UGH!!!” Then they were laughing, too, and Ned insisted on staying to the end to get even for the many things Bill had done in the past.

We decided we’d better leave it the band-aids off, which meant that Bill had to stay indoors to keep dirt out. With that development, and the seriousness of the infection, Bill finally agreed to see a doctor. We went to the hospital in Medford (Oregon) the next morning. The doctor kept his hands in his pockets the entire time he looked at Bill, said he had severe staph infection along with the poison oak. He prescribed several medications, along with many restrictions to keep it from spreading. This really sent Bill into the depths of depression, and it took us several days to get all the soaking, etc., worked out in our small motorhome. But then we came up with a plan to ease his problem. I became Bill’s “surrogate dredger,” and this is how it worked: (Until then, I had always participated in his dredging, but only as a dredge-tender, or by shoveling tailings.) Bill would stand up on the bank, about 30 feet high, and tell me where to dredge, and shout directions, which I was to follow. In most places here, bedrock was extremely shallow, only 2 or 3 feet deep, and I soon found that working the nozzle was actually a lot of fun. It sucked up all the stuff, and then I could fan the crevices and cracks; and most of the time, there would be some gold that I could see and pick up with my tweezers.

It was hard to hear Bill over the dredge engine, and he was frustrated because he could not see very well what I was doing. More often than not, he said that the gold I was recovering wasn’t good enough, and that I should move to a different place. Now this was the very first gold that I personally had ever found on my own, and I had a very special feeling for it. I was most-often content to stay right where I was. Also, one of the things I am not known for is my muscles or athletic ability, and dragging (the water wasn’t deep enough to float the dredge in many places) a 4-inch dredge over rocks is not a fun thing to do. Besides, I always believed he did not sample thoroughly enough when testing.

Naturally, this led to much “discussion,” something we are experienced at, having been married a long time. At times, in fact, I was sorry that we were no longer using tape. I’d have really enjoyed ripping some off. However, I would eventually realize, or be reminded, that I was only a surrogate dredger, and remember that I was supposed to be helping him; so I would usually move. Eventually, however, I lost all my understanding, patience, energy, and enthusiasm, and we gave up that experiment.

The next week, when we weren’t snarling and snapping at each other, Bill read and listened to the radio, and I recruited Dori to help me refurbish the “Three-Holer,” when I needed to get away. We cleaned out the nests, put a spare piece of outdoor carpet on the floor and contact paper down the seats, hung a lantern and fixed the latch on the door. Then we cleaned the path and lined it with rocks. Ned helped me fix a metal poker we heated in the campfire, and I burned “3-Holer” into a piece of picturesque wood that pointed the way. Then finally, the day arrived when Bill could go back into the water. We had four days left for dredging.

We set the dredge up in a deeper pool that he wanted to try, but we developed a problem right away. In dragging the dredge around, one of the pontoons was taking in water, and Bill was too anxious to take the time to fix it right. That was a mistake.

He hit good gold right away, but we were using every bit of hose we had. Each time he’d tug on the hose, the pontoon would settle a little bit deeper in the water. Eventually, the dredge would be in danger of sinking, and he would have to come up to pump it out.

Bill worked a very long day; and when he came out, he did no more than shower, grab a sandwich, and fall into bed. He got up early the next morning, put his suit on immediately, and we went to the creek. By this time, the heat wave was long gone, and it didn’t climb above 45 degrees until the sun came over the mountain, late in the morning. I did not argue, however. He was doing some serious dredging, now; and he was even angrier each time he had to come up to pump the pontoon.

I tried to build a dam under the dredge. But each time he pulled the hose, the rocks would fall, and I had to start over. By early afternoon, I had given up; and when I signaled him to come up about the tenth time, he came up boiling mad. He broke water like a fish on a hook, ripped the regulator from his mouth, and told us all just what he thought of his pontoon, the manufacturers of the dredge, dredging, and life in general. The whole time he was talking, he was shedding his gear; and when he reached the bank, he started pulling in the dredge, and proceeded to break it down.

Our friends quietly faded away, and I found a rock to sit on a safe distance away. When Bill finished, he told me I could pan the concentrates or not, he didn’t care. I did pan them after he went back to camp; and as I took a break before panning the last pan, I sat on my rock in the middle of the creek, and the beauty of the scene struck me, again. I listened to the creek as I watched the rays of sunlight shining through the trees to dance on the water. The black-berry bushes twined among the trees and ripe with big, luscious fruit, hung low over the water, and the air smelled so fresh and sweet I could taste it. The image is as bright today in my mind as when I sat there, and with the image comes the feeling of peace and contentment I felt at that moment.

We packed up that night and started home the next morning. Bill was very silent through the packing and the drive home. About halfway home, I was beginning to get concerned that he was really finished with mining, when out of the blue he said, “Next year.”

 

BY MARCY STUMPF/FOLEY

 

Dredging below the chute

Bill Stumpf keeps a careful eye on dredging equipment while son David dredges 24 feet beneath a fast-water chute on the Yuba, River. The chute is out of sight to the left of current which can be seen at center-left of above photo. Bubbles at lower-left are from David’s hookah air supply, as he makes his way to the bottom of their hole.

As I sat in the sun on the bank of the North Fork of the Yuba River in California’s Mother Lode country, I basked in the warmth as I watched my 19-year-old son David swiftly cross the river on top of a small dam of rocks that someone had left below where we were dredging. Followed by his dog, Kona, he urged her on as she slipped and slithered her way across the slippery rocks. I didn’t know how he did it. I cursed and fell every time I ventured more than a few feet from the bank!

David was warming himself up by playing with Kona, preparing for the first dive of the day. My husband, Bill, gassed-up the dredge and made sure all was in running order.

We were working a “chute” where the river narrowed between bedrock dikes, pushing the water with tremendous force through the narrow opening, then dropping it into a large pool. We were set up in the pool, and had every inch of hose we owned on our 5-inch dredge to reach the bottom.

Bill began working in 18 feet of water, adding as much weight as he could to his weight belt to stay down. They had even fastened a chain to a piece of bedrock on the bank so Bill could “walk” down into the hole each day. They chopped, pried and levered their way through several feet of extremely hard hard-pack; and when they reached the bottom, they found a natural channel had been cut into the bedrock, about four feet across, and they weren’t sure how deep. Bill began suffering from nosebleeds at about 22 feet down, so David was continuing the dives on his own. We were giving him a couple of days to satisfy his curiosity as to what was at the bottom.

David and Kona ran back up to where I was sitting, and David laughed as Kona shook herself, spraying me with water and rubbing against me as I protested. He began adding all his gear for diving. This was a cold river, and he already had an acrylic bodysuit made for diving under his 1/4-inch wet suit.

David was thin and had a hard time staying warm any time of year in the Yuba, but this was springtime-the water was very cold. He wore boat shoes over his dive booties, work gloves on top of wetsuit gloves, and finally a hot water line to bring warm water inside his suit.

At last, he was ready, and I opened my mouth to complain about his weight belts, but could see that he could hardly move and decided to keep quiet. I had an ongoing thing about the weight belts. Being so thin, it was very difficult for him to keep the quick- release buckles in front; and wearing two belts compounded the problem. I knew from the past, that even if he had them on straight when he went down, he worked so fast and furious below that within 15 minutes, they would be working their way around his body. We’d “discussed” it often.

David adjusted his mask and descended; Bill went out to the dredge; and I settled back. It wasn’t often I had time to relax, and this was the last day we would be working here. We’d decided to pull out tonight. David was now diving at 24 feet; and as he started dredging, the dredge hose pulled the dredge out into the river a bit more–stretching to reach the entire length. Soon, material began flowing through the sluice box.

David finished the first dive, we had lunch, and he went down again. I was about to doze off when suddenly, a loud noise startled me. As I jumped up, I saw that David’s airline had blown off the air compressor. With a huge “whooshing” noise, it rapidly snaked across the river as air from the reserve tank rushed out of the open end.

I began to panic immediately. Bill did not have his wetsuit jacket or weight belt, and the swift current would force him downriver if he attempted to cross the current to David.

We waited for long moments on the bank for David to appear but, he didn’t.

Underwater, David gasped as he drew water instead of air into his mouth and quickly began fumbling through two pair of gloves for the quick-releases on his belts. He finally found one and dropped it but lost more precious moments looking for the other. He was fast running out of time and couldn’t find it!

He finally decided to force himself to the surface wearing one belt. But as he stepped out of the first weight belt, he stumbled and his boat shoe became entangled in the metal crate which he used to carry rocks out of the dredge hole! Now he had to fight panic as he worked quickly to extricate himself. It was dark and murky down there as he struggled to remove his foot from the shoe which was still caught in the metal crate. At last, he was free, but did he have enough air left after his struggles to make it to the top?

Up on top, I was already in tears. It seemed we’d waited hours, and Bill was rapidly descending the chain to see what he could do. He had to try something, even if it was wrong!

Just then, in a roar of water, air, coughing and shouting, David burst through the surface of the water and Bill dove for him, helping him out of the current and to the bank, where he lay a long time, coughing and spitting water.

We felt very lucky, and we were a sober and wiser group when we left that day. We’d learned several good lessons, and would like to re-emphasis them because they are important ones:

1) Always make sure your weight belt is tight and you can reach your quick-release buckle (and make sure it’s in good working order).

2) Make sure that any line connected to your air compressor is a “HEAT RESISTANT” line (usually red or black). Air coming out of the compressor is hot, and regular airline will NOT stand up to that heat. Remember: your life depends on the air from that line!

3) And, finally, we learned that curiosity that leads you into danger is best left to cats.

 

By Dave McCracken

This system combines two classification screens to more-effectively separate material-feed into three separate size-fractions, each which is directed into a different recovery system.

Dave Mack


Riffles in box Three sections of screen

Classification is the Key to Fine Gold Recovery

It is well-established that if you want to effectively recover finer particles of gold, you must first separate them from the larger-sized materials which are being washed through your recovery system by a higher-velocity flow of water. The small-sized material can then be directed to a milder-flow of water over a shorter set of riffles. The smaller you can classify the size of the material, which can be directed by and even milder flow of water over lower-profile riffles, the finer-sized gold that you can effectively recover.

This is all rather easy to accomplish with surface processing plants where earth-moving equipment can be used to feed a plant some distance above the ground. Feeding a plant well above the ground allows plenty of drop for water and gravity to direct material through multiple sizes of classification screens. Then, gravity can be used to direct the different size-factions of material to separate recovery systems with controlled water-flows and riffle sizes specifically designed to recover gold effectively from each size-fraction.

Conventional Suction Dredges do not allow for Much Classification

I am not sure what the exact formula is, but I know from long experience that every inch you lift the feed of a suction dredge above the surface of the water, you lose a considerable amount of suction-power at the dredge nozzle. Therefore, since we have to accomplish both classification and gold recovery from a feed that can only be effectively lifted about 4-to-6 inches above the surface, our options are pretty limited.

Dredge manufacturers have worked out different ways to direct classified materials into slower-moving recovery systems. Generally these methods fall into three categories:

1) Placing a classification screen over top of a set of riffles. This way, smaller-sized material can fall through the screen into a slower-moving flow of water over riffles that are more-protected from higher-velocity water-flow. You see screened-over riffles in common use today.

2) Placing a classification screen towards the head of the sluice box, and then directing the classified material to one or two completely separate sluices which have a slower-moving flow of water over lower-profile riffles. This was most commonly seen in the form of side-by-side triple sluices during the 80’s and early 90’s. While effective, the problem with the side-by-side sluices is that the side sluice(s) normally have to be placed on top of the dredge’s pontoons. Therefore, in order for gravity to make everything work right, the initial feed to the dredge has to be lifted higher out of the water. This causes a power-loss at the nozzle. So you do not see as many side-by-side recovery systems in production on suction dredges these days.

3) Placing a classification screen somewhere towards the upper-end of the recovery system, and directing the classified material to a slower-moving recovery system which is located directly below the main box. This is commonly referred to as an “over-under recovery system, and remains in popular use today. An over-under system is most commonly accomplished in the same basic sluice box, which is constructed with a removable false bottom. By this, I mean two separate recovery systems, one sitting over top of the other, in the same sluice box.

I cannot go into which of these systems are better or worse; because there are too many variables in play, and experienced prospectors can work it out to get the best recovery possible out of any of these designs, each which would likely be comparable to the other. That’s because all three of these system concepts depend upon a single classification screen to remove some portion of the smaller-sized material from the higher-velocity water-flow which is required in a dredge.

This particular discussion has more to do with the effectiveness and size of material-classification. Remember, with conventional suction dredges, we are using water-flow to move all our material across any classification screen(s) that we are using. The larger the dredge, the faster and more powerful the water-flow must be to wash larger-sized rocks and a larger volume of material through the sluice. The faster the flow, the less time that smaller-sized material has to drop through a classification screen. The smaller the openings in the screen, the less opportunity smaller-sized material has to drop through the screen. The shorter the screen, the less opportunity smaller-sized material has to drop through the screen.

Each of these factors combine into to the effectiveness of the dredge’s classification. For example, the substantial flow of water to move 5-inch sized material over 10 inches of 1/8th inch punch plate does not present much opportunity for minus-1/8th material to drop through the screen. So while a separate slower-moving recovery system might be doing a better job recovering smaller-sized gold, perhaps the classification system is only allowing 5% of the finer-sized gold to be directed into the slower-moving recovery system. In other words, the effectiveness of your recovery system is largely affected by how you are attempting to classify and separate the smaller-sized material.

Therefore, on the subject of fine gold recovery with suction dredges, our first challenge is to try and accomplish effective classification as best we can out of a strong flow of water (strong enough to move the largest rocks you are sucking up through the recovery system).

Years ago, we overcame this whole challenge on commercial dredges by working out a mechanized shaker screen at water level which provided 100% classification of the dredge feed. Minus-sized material from the screen was dropped into a sump where it was redirected by a gravel pump to an elevated feed on a surface-type recovery system either on the shore, or on a separate floating platform.

But it is impractical and too expensive to try and place a mechanized classification screen on smaller-sized dredges — which also must remain more portable for sampling. Therefore, on conventional dredges, until someone comes up with something different (if ever), we must continue to make due with a water-flow to wash material across our classification screen(s). With this in mind, here are a few principles which I believe to be true:

1) The faster the flow, the more difficult it is to drop finer-sized material through the openings of a screen in your sluice box.

2) The smaller the holes in the screen, the less finer-sized material you can expect to drop through the openings out of the high-velocity flow required to move larger material through your sluice box. Example: Using the same flow of water and material, you could expect more fine-size material to drop through a 3/8-mesh screen, than a 1/8-mesh screen. This is because the larger openings provide a bigger doorway for material to drop through.

3) The shorter the length of a classification screen, the less fine-sized material you can expect to drop though. Therefore, we want the classification screens to be as long as we can get away with. Longer screen means more opportunity for finder-sized material to drop through.

4) Effective classification of finer-sized material can be accomplished better in stages. For example, first drop 3/8-minus material out of the fastest flow in the box. Then, using a slower flow of water, direct the minus-3/8 material over a 1/8-inch screen.

5) Since we only have 4 or 5 inches of drop to work with from the feed of a conventional suction dredge, there is only room for two levels of classification screen before we must drop the finest-sized material into a recovery system. Otherwise, we will be underwater where reduced gravity is not going to allow water-flow to work for us, anymore.

What to use for a fine-gold recovery system?

material in rifflesAs I have explained elsewhere, I believe it is necessary to direct finer-sized material over lower-profile riffles that will continue to remain fluid under a mild flow of water, even when they are full of concentrated (heavy) material. If you have not reviewed the theory on this, I strongly suggest you read “The Size of Riffles.”

There are different kinds of low-profile fine gold recovery systems on the market. Just take a look around and make your own choice.

We have been using the green, plastic Le Trap sluices to reduce the volume of our dredge and high-banking concentrates all the way back to the early 90’s. I cannot overstate how effective these Le Trap Sluices are. When set up with the proper water-flow, a Le Trap will recover all the visible gold from a feed of minus-1/8th material with losses that are so minimal as to be meaningless. We know this from panning the tailings hundreds of times over the many years.

So when we needed something to recover overwhelming amounts of fine gold using a dredge on a river in Cambodia, I started giving a lot of thought to how we could more-effectively classify dredged material down to minus-1/8th, and direct the material in a controlled flow over Le Trap-type riffles.

Dredge 1Dredge 2

Several very experienced dredge-builders and I created the prototype several years ago from a Precision 6-inch dredge. To accomplish our objective, we assembled two layers of classification screen, each which could be independently raised or lowered, so that we could adjust the water-flow over the riffles, and over each of the screens. The top screen is 3/8-inch mesh. This is to allow the larger-sized material and strong water-flow to wash through the box without affecting the plastic riffles along the bottom. Minus-3/8ths material drops through the top screen onto a 1/8th-inch mesh screen, where the water flow is substantially reduced. Slower water-flow then allows finer-sized material more-extended contact with the 1/8th-inch screen.Double screens over riffles

Material that drops through the 1/8-inch screen is then carried over the Le-Trap sluice by a mild flow of water. By adjusting the height of the lower screen over the plastic riffles, and the slope of the sluice box, we are able to control the amount of water-flow over the lower-profile riffles.

Since the sluice box in the 6-inch Precision was much wider than a normal Le Trap sluice, the prototype required quite a lot of work in a cut and paste project (using of 4 or 5 Le Traps) to create the first underlay recovery system for a dredge.

Fine goldWe invested quite a lot of time and energy into the prototype. All you have to do is look at how much (very fine) gold we found on that river in Cambodia to understand why we did it. We were shipping this 6-incher over to resume (sampling) where we had left off on that earlier project.

 

During trials on the Klamath, I was amazed at how much (very) fine gold we recovered out of just a minute or so of dredging loose material off the surface!

Our trial run on the Klamath River near Happy Camp in March several years ago turned up so much fine gold out of the lose surface gravel, that I hesitated over sending the 6-inch prototype to Cambodia!

I have been told for 30 years that there is so much fine gold in the river that we are losing out of our conventional dredges, if we could just recover it, we could make the river pay just by pumping any gravel! This new system seemed to prove that theory may be true, especially with these higher gold prices. But it was March and the Klamath was cold; so we shipped the original prototype dredge to Cambodia.Cambodia Dredging

I devoted plenty of time in Cambodia (underwater) observing three separate flows of material coming off the back-end of the recovery system; and it was poetry in motion!

I have a non-disclosure agreement with our clients in Cambodia, so I cannot go into details or images of how well the new system performed over there. But I can say that I devoted a lot of time underwater watching water and material exit the sluice box in three separate flows; and the double-screen system is by far the best thing I have seen on a conventional dredge for effectively classifying material into three separate size-fractions.

Because of that, my experienced buddies and I invested quite a lot of time during the 2009 mining season to adapt the double-screen system to my 8-inch dredge. 8-inch dredge

Building double classification screens, so they can be adjusted up and down to allow you to set three separate water-flows through the sluice box, requires quite a lot of labor! But getting this right is the foundation of this whole concept.

Here are some video links which demonstrate the system being used on my 8-incher. These give you a much better look at how we created a double-screen classification system over top of the fine gold recovery: Take a look at the size of the gold we were recovering!

 

As (bad) luck would have it, the State of California imposed a temporary ban on suction dredging just as we completed the double-screen refit on my 8-inch dredge. This forced us up onto the Rogue River in Southern Oregon, where we are limited to smaller-sized dredges. So my 8-incher had to be set aside.

Picking up on the idea of my double-sluice conversion over a plastic sluice, one industry-fabricator was recently promoting the idea of refitting conventional sluices (using the plastic sluice underlay) which do not include the double-screen classification, and do not allow the screens to be adjusted. I would advise caution on short-cutting these concepts. That is what prompted me to write this article. Since these conversions must be accomplished through custom shop work, I wanted to provide you with some background so you can make your own decisions.

While there is still a lot to learn, for the reasons I outlined above in points 1 through 5, I personally do not believe that you can classify raw material effectively from a 4, 5 or 6-inch (or larger) dredge being washed across an 8-mesh screen by high-velocity water.

I believe effective classification must be accomplished in stages; first to drop the 3/8-minus material out of the higher-velocity flow which is needed to push the larger-sized material through the sluice. Then, drop the 1/8-minus out of the much slower flow necessary to wash 3/8-inch material across the lower screen.

I believe you have to be able to adjust the height of each screen (set the water velocity) in order to get a workable water-flow over the riffles and over the 1/8-mesh screen. The water-flow cannot be so much that you boil-out the riffles, and it cannot be so little that you load the riffles. You also must not pack up the space between the two screens!

Eric Bosch and I first experimented with this double-screen concept in the early 90’s. But we made the mistake of fixing both screens (welded them where we estimated they ought to be). Our estimate of how much water-flow was needed between the screens was incorrect; the space between the screens packed solid with material; and the whole system failed.

Also, if you cannot adjust the water-flow over the riffles, and between the screens, you cannot compensate for different conditions in different areas.

Dave's goldAs an example, there is an overwhelming amount of heavy black sand and small iron rocks (and lead) along the Rogue River in Southern Oregon. We do not encounter this magnitude of heavies on our properties along the Klamath River in northern California. The heavies along the Rogue completely overwhelmed my fixed recovery system (buried the riffles on my 5-inch conventional dredge) at the beginning of last season. This prompted me to place smaller riffles below my (fixed) screen, spaced further apart. That worked better, and I recovered a lot of gold. But I believe I lost most of the (very) fine gold (I could see it in the last riffle) that was fed into my sluice box. This has prompted me to refit the recovery system on one of my 5-inch dredges for the upcoming season.

The images at the beginning of this article show an early version of the double-screen system that was designed for deposits we located in Cambodia. We did not find a single particle of gold on that river that was larger than the size of a pinhead. Since larger-sized gold was not present, we did not want to waste the (very) limited amount of room we had to work with by installing riffles for larger gold. Those images are helpful in showing the plastic sluice underlays (there are two of them, one following the other).

The images at the beginning of this article show the Cambodian version of the double-screen refit. Those images are helpful in showing the initial plastic sluice underlays that we were using (there are two of them, one following the other).

Header areaHeader with screen and miners moss

The images in this article also show a header section near the upper-end of the box. My initial theory was that the initial impact of the water and material must bottom-out on something other than plastic sluice underlays. We experimented with a combination of different kinds of heavy screens over top of miners moss or ribbed rubber matting to absorb the initial force of the water and material where it bottoms-out at the head of the sluice box. Fortunately, nearly everything we have tried in the header section seemed to work really well. As you will read below, we have since evolved completely away from using plastic sluice underlays… Header area after running

This is what the header area looked like under the screens when we shut the dredge off while dredging at production speed. You can see how classified material kind of mounds up there before flowing onto the slick plate of the riffle system. We are finding that quite a lot of (very) fine gold also gets trapped in the header section!

We have noticed that while in production, material tends to mound on top of the header section under the 8-mesh screen, and then wash off the mound onto the first sluice underlay. This is really good, as long as the mound does not rise up and pack-up the whole space between the screens.

While we were still using them, the plastic sluice underlays followed just behind the header section. This allowed water-flow and material to settle out and slow down before being washed across the lower profile riffles.

 

 

 

Two kinds of rifflesriffle section

Notice that the shorter section of riffles (remains protected by the top screen) are present only to process classified material which washes across the 8-mesh (lower) screen in the box.

Adding larger riffles for bigger gold

We have since evolved the system, adding two sets of different-sized riffles to catch larger-sized gold. We accomplished this by replacing one of the 1/8-mesh (lower) screens with a solid bottom that supports both sets of the added riffles. The false bottom continues to allow an under current to wash minus 1/8th material across a low-profile underlay, just like in the Cambodia version.

The first set of riffles on top of the false bottom is designed to process the material that drops through the 3/8-inch screen, but is too large to drop through the 1/8th-inch screen (1/8th-to-3/8th size-fraction). This would be for small nugget-sized gold. That size-range of gold is very easy to recover.

As I discussed in The Size of Riffles, the height of a riffle necessary to recover a piece of gold normally does not need to be much taller than the size of the gold you are trying to trap. So the first set of riffles for larger gold can be rather short. Notice that the first set of riffles continues to be protected by an extension of the top screen.

Then we added a final set of open riffles (not covered by a classification screen) to catch any gold we might suck up that is larger than 3/8th-inch (larger nuggets). For example, depending upon where you dredge, the Rogue River in Southern Oregon can produce a lot of gold in these larger sizes. But the river is loaded with fine gold, as well.

It is kind of hard to see in the images; but if you look close, you can see the plastic sluice under the false bottom where we placed the riffles for larger gold.

Since you cannot buy these double-screen systems ready-made, you either have to refit your own sluice, or arrange with a capable fabricator to do it for you. With this in mind, I will follow with some basic directions which we have learned from building several of these systems:

Building the System

If you look at a Le Trap, you will see that it has 3 important sections: There is a slick plate at the top. This is vital; because it allows the water-flow to smooth out before material encounters the riffles. Then there are some short riffles. These capture all the gold unless you over-feed the box with too much material at once, or unless you completely fill the short riffles with gold. Then there are some deeper riffles which more-aggressively capture all the rest of the gold when you do over-feed the short riffles up front. “Overfeeding” has more to do with the amount of heavy iron material, than light sand or gravel. I will talk more about this down below.

Close-up of rifflesThis image shows two sluice underlays following the header section (with no screens on top)

When we planned these sluice underlay riffle-panels, we included the slick plate up front, and then went about 50/50 the rest of the way using short and deep riffles. We did this because I wanted more of the short-type riffles that work so well in the Le Trap. But I did not want to eliminate the deeper riffles which create such a strong back-flow, especially at times when lots of material is being fed across the box. But through extensive trial and error using the third evolution of this system this past season, we discovered that the higher velocity flows that are necessary to move volume-amounts of classified material across the plastic riffles were also causing some of the trapped fine gold to boil out of the system. Too bad! We then tried Keene’s new ribbed rubber matting (good stuff!) and ended up with the same result (we were losing some gold). So it appears that these plastic and rubber riffle systems are better suited for final concentrating work, rather than being used in the volume production setting inside of a dredge recovery system (more on this below).

Because the double-screen assemblies are heavy, in order to manage them, you have to divide your sluice box into several smaller sections. How many sections depends upon how long your sluice box is. You will notice in the images at the top of this article that we divided my 5-inch dredge into three separate sections. One section is over the header area. The other two sections are over top of two identical sluice underlays. It is wise to divide the sluice underlay sections into exactly the same sizes. This way, the parts can be interchanged when it is time to reassemble your recovery system.

We build the double-screen assemblies so they rest exactly upon the sluice underlays. This allows us to take apart one only portion of the sluice box if that is all we want to look at or clean-up.

The screen assemblies are built so the aluminum side supports slide down inside the sluice box and sit directly on top of the side rails of the sluice underlays. This pins everything down snuggly against the bottom of the sluice box. Then we snap the screen assemblies down tight to make sure everything stays in place when we are running the dredge or moving it around on land or in the river.

Sluice Underlays

Close-up of matting
Close-up of both

Through a very substantial amount of trial and error this past season, we discovered that both the plastic sluice material and also the new Keene rubber matting were losing gold from under the twin screens.

Expanded metalWe finally found the right combination by using a wide, raised expanded metal over top of deep ribbed rubber matting. The aggressive expanded metal was dropping the gold out of the classified feed. Once it was in the ribbed mat, the gold was not getting away. This combination was so effective, we even replaced our header section with the same expanded metal, though we used miners moss underneath, rather than ribbed rubber matting.

We did multiple checks; and we were never able to find a single speck of gold in the final 25% of our recovery system, even though we were mostly dredging in fine gold pay-streaks (loaded with fines in the front section of the recovery system) all season.

This is important: The width of the sluice underlays (and screen assemblies) have to be a bit narrower than the inside of your sluice box. Otherwise, it is too difficult to get them in and out when you want to perform a clean-up or reassemble the recovery system. I always allow a margin of around 1/8th or 3/16ths of an inch, maybe even ¼-inch on a wider sluice.

Note: We have since replaced the sluice underlay in the drawing above by welding some 3/4-inch angle iron on both sides of the expanded metal to create side rails that the double-screen assemblies can rest on top of.

The following video sequence should give you a better idea of what we have ended up with as a sluice underlay:

The width of your side rails needs to be greater than the margin you are allowing between the sluice underlay and the side of your sluice box. This is so you will be sure that the sides of the screen assembly are going to slide down and meet the rails of the sluice underlay.

Double-screen Assemblies

Sliding the second screen into the frameThese add up to some weight; so you have to plan how to divide your sluice box into small-enough sections that you can lift the screen assemblies out of your sluice box without too much trouble. On the other hand, you want to minimize how many sections you have to make, because these are very labor-intensive to build.

The length and width of the screen assembly should match the sluice underlay, so that they will marry-up exactly when you set the screen assembly down on top of the underlay.

 

Screen LatchYou have to use aluminum plate for the sides to keep the overall weight of the screen assembly from adding up too much. The height of the sides needs to be at least as tall as your sluice box. I build mine high enough that I have room to adapt a latch to snap everything down tight.

Once you have the aluminum sides of your screen assembly cut to size, bring them all to your local machinist, and ask him to mill slots so that you will be able to raise and lower your two screens. If you bring the machinist one of the lag bolts you are going to use, he can mill the slots just wide enough to allow the lags to slide up and down freely, but not so wide that the lag is allowed to turn in the slot when you are tightening or loosening the nuts that hold the screens in place. Just to make sure I will have the full range of adjustment, I have the slots milled nearly the full height of the sides, to within about ¾ inch of the edge, equally at the top and the bottom. Each aluminum side needs three slots; one on each end and another in the exact middle.

You can source thin-headed lag bolts from fastener supply outlets. If you look, I’ll bet you can find them on line. If you cannot find them, then you have to grind the heads down on regular lag bolts, because normal heads are too thick and will take up too much space between the screens and the sluice box.

Helpful hint: The head-thickness of lag bolts on both sides of the screen assembly need to be included when you are deciding how wide your screen assembly and sluice underlay need to be for everything to slide in and out of your sluice box without too much difficulty.

Another helpful hint: If you cut the side plates all the same size, and have the machinist mill the slots exactly the same on all the plates, all the pieces will be interchangeable, and then you can jig-up to drill standardized holes in the side rails to your classification screens.

The lag bolts need to be heavy enough to support the weight of your screens (perhaps 5/16ths or 3/8ths). Different boxes have different widths, meaning heavier screens. It is better to go a little heavy on the lag bolts. The bolts need to be long enough to extend through the aluminum side, through the side rail of the screen, and have enough room for a flat washer and self-locking nut.

Screen frameStacking screens

Ideally, you build all your screens exactly the same size, so they can be interchanged. We accomplish this by rigging up a jig to cut all the side rails exactly the same; then to weld the frames all the same; and then to drill all the bolt holes the same. We drill the bolt holes in the side rails a little large to allow some margin for error.

Side rails for the screens need to be heavy enough to support the weight of your screens with you standing on top of them. By heavy, I am discussing rail thickness. Because, if you go too wide, you will limit how close you can adjust the distance between the screens. Thicker 1.25-inch-wide strap has worked well on my refits for the screen side rails.

Unless you want to buy whole new sheets of screen (expensive), I suggest you source used screen at your local metal scrap yard. The one we go to in White City, Oregon nearly always has a large supply in all mesh sizes. I gather that commercial screening plants replace their screens pretty often – most of it still in good enough condition to meet our needs.

The top screen (around 3/8th-inch openings) needs to be heavy enough to span the length and width of your screen assemblies without needing additional support, and without bending or sagging when you stand on top of the finished screen.

The lower screen (around 1/8th-inch openings) needs to be heavy enough to span the length and width of your screen assemblies without needing additional support.

Helpful note: I experimented with a finer-mesh lower screen (about 1/10th-inch openings), and had trouble with small particles of rock plugging up all the holes. We call this “blinding.” It’s when the holes in a screen all become plugged-up (or overwhelmed by too much feed), preventing the screen from doing its job. So it would appear that you do not want to use a mesh on the lower screen much smaller than 1/8th-inch.

Cutting screenWe have had good luck cutting the screens to size using a cutoff wheel on a hand-held grinder. If your side rails are made of thick material, you should be able to cut the screen to size and weld it down directly on top of the side rail frame. Grind all the edges nice and smooth, so your hands are not getting cut up once you start working with these screens on your dredge.

Helpful note: If you weld the bottom screen on top of the side rails, and the top screen on the bottom of the side rails, you will be able to loosen or tighten the center bolts in the side plate much more easily. I am talking about the lag bolts which attach the screens to the aluminum side plates. If you end up with your center bolts between the screens, it is much more difficult to get at them!

Another helpful note: You might want to drill your holes just off center through the side rails. This way, you can still get a socket on the nuts after the screen is welded on.

These helpful notes are things I have learned the hard way!

When you assemble the screens, a good starting point would be so that the bottom screen rests maybe just a little more than an inch above the plastic sluice.

Helpful hint: If you make the side rails on your sluice underlay too tall, it will limit how far down you can slide your lower screen.

We have had pretty good results lifting the upper screen about 1.25 inches above the lower screen.

This is important: To add more flexibility, if not already present, we modify the sluice box supports on the dredge so that we can raise and lower the slope of the box. This creates a very helpful mechanism for adjusting flow rates.

Once in the field, you can make adjustments to sluice slope and height of each screen to work out the needed velocity in three separate water-flows: First, the water-flow across the sluice; then the water-flow between the screens; and finally, the water flow across the top screen.

I already discussed above how to replace the lower screen with a false flat bottom which you can place riffles on top of to recover the larger classifications of gold. In my view, it is more effective to do this in the lower section of the sluice box (though, I mounted the riffles for larger gold in the upper-end of the sluice on my 8-inch dredge). I know this viewpoint is not popular with some prospectors, because they do not want to chance losing a bigger piece of gold that is allowed to get so close to the end of the recovery system. My answer to this is that gold is really heavy stuff! If there is some anomaly (like the gold is attached to quartz rock which makes the piece lighter) that would keep it from trapping in a set of riffles in the back-end of the box, it probably will not drop out in the front portion of the box, either.

Other than in a very rare occasion, the vast majority of the gold you will recover is small enough to drop through an 8-mesh screen. Some important part of that gold is so fine as to be difficult to recover using the recovery system on a conventional suction dredge. The journey of fine gold through 20 feet of suction hose, and then up through a diffuser (flare jet) places most of this fine gold right on the bottom of the material as it first flows into the sluice – right where you want it; right where it is most likely to drop through the classification screens out of the higher-velocity flows, which otherwise can wash it through your box like sand. Better, I think, to get the minus-1/8th gold into a safe holding area as the first priority.

If you look closely at the diagram just above, you will see another reason to put the larger riffles towards the rear-end of a double-screen system. See how all or most of the fines are directed through an undercurrent below the larger riffles? This means the larger riffles will not be getting flooded and loaded up with fine-sized material. So, while fine material gets more exposure to low-profile riffles (where it belongs), the deeper riffles remain more open so that larger gold has a place to drop out of the flow.

But that is just my view. You guys can do it any way you decide to!Riffles just after shut-down

The reason you see rocks on top of the double-screens, is because we turned the dredge off while we were pumping at production speed. See how the riffles are working? They are not loading up, and they are not boiling- out. This means the system was working!

I do my classification and sluice flow adjustments when running the dredge at normal operating speed while I am feeding the nozzle at production speed in hard-packed streambed. I arrange for a second person to kill the motor without notice. Then, when I disassemble the system, I can see how the sluice and screens are performing while I am pumping gold and gravel into them at production speed.

Between these explanations, the drawings above, the images and the video segments, you guys (or the fabricator who will help you) should be able to see how these systems come together, and how they work. They provide you with a whole lot more than I started with!

Here follows a video segment we put together at the end of this last season which demonstrates the most recent evolution of this very effective dredge recovery system:

Other Considerations

Trial runPossible need for added floatation: As I mentioned above, these double-screen assemblies are heavy. So if you do a refit of your sluice, you may also consider adding some floatation to your dredge. When I refit the original 6-inch Precision dredge for Cambodia (image above), I also had new, larger aluminum pontoons made up to provide enough floatation so that I could also stand on the dredge while it was running. Nice!

Having enough water-flow to make double-screens work: Every dredge is a bit different. Before refitting your dredge with a double-screen system, you might turn the dredge up and watch the water-flow across your existing recovery system and estimate if you will have enough water volume to provide sufficient velocity to meet the needs of three separate flows.

Overfeeding the system: Every recovery system has its volume-limits! Since I find nearly all of my high-grade gold associated with hard-pack, I design my recovery systems to process average material which makes up normal hard-packed streambed that was put in place during the evolution of a major storm event. Normal streambed consists of rocks which are fitted together, with smaller rocks and pebbles in-between, with gravel, sand and silt filling the smaller spaces. When taking apart normal hard-packed streambeds, the smaller-sized material only comprises a small fraction of the overall volume. Therefore, I have yet to overwhelm one of these double-screen systems while production-dredging in hard-packed material.

On the other hand, if you go out on the river and just start pumping sand or loose, classified gravel (like tailings), a much-higher percentage of the material will penetrate the screens and you will almost certainly overload (blind) the sluice with too much material – and perhaps even pack-up the space between the sluice and the bottom screen. Let me be clear: This double-screen system is not designed to process sand or loose gravel deposits or tailings from some earlier mining activity!

This same concern is true for any type of recovery system used on a suction dredge. So it is important for you to be mindful of the material that you are feeding into your suction nozzle. If it is a layer of sand or loose gravel, you should either slow down; or you can speed up and pump it through as fast as you can; and then go up and make sure your system is no longer packed-up before you start feeding pay-dirt into your dredge.

The fine gold needs to be present: The only good place to test the effectiveness of your recovery system is when you are feeding high-grade into your dredge. The more gold you feed into the recovery system, the better you can see how well it is working.

Effectiveness cannot be discounted just because you see a speck or two of gold down towards the end of your box. The thing to look at is where most of the gold is stopping.

So many times, I have watched others decide their recovery system is not working, only because they are not recovering much gold. You cannot recover much gold if it is not present in the streambed that you are dredging! So I suggest you reserve judgment until you test your system in high-grade.

 

 
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By Dave McCracken

“A Preliminary Evaluation”

Dave Mack

Note: This is the non-proprietary portion of an initial report from a preliminary evaluation of a potential suction dredging project in Northern Sumatra (Indonesia). The opportunity to do something with this prospect still exists. The evaluation was done in April of 2005. The gold values have been modified to reflect gold prices in mid 2010.


This project is located on the island of Sumatra in Indonesia, directly to the west of Singapore. I arrived there by flying to Singapore, and then by taking a 1-hour boat-ride to Batam Island (Indonesia). From there, I caught a flight to Padang. Padang is the capital of Western Sumatra. At the time, this was a better connection than trying to fly directly to Padang from Singapore.

A representative from the company that hired me was waiting at the airport in Padang. We then drove 2 hours north to a place called Bukittinggi where they have a home and office. The company manager was already up at the base camp. They had arranged for a driver to bring me up there on the following day.

Bukittinggi is a lot like the towns we have in the West. In fact, as shown in the following video segment, if it were not for the different language on the signs, this city could easily be mistaken for almost any town in America.

The roads and other infrastructure in western Sumatra are pretty darn good. The people seem nice. Things are relatively inexpensive. English is not spoken very much, but the people are forgiving and do their best to help figure things out.

The location of this project was situated about a third of the way north to Medan (from Padang). Medan is the capital of northern Sumatra. It is the second-largest city in Indonesia.

There is a good road that leads to the project-area and follows alongside the river. So accessibility to the river is generally very good.The following video sequence was taken as we were driving north to the project site. You will notice that they drive on the left side of the road in Sumatra:

The river is about the same size as the Klamath River in northern California, but will reduce in size as the dry season progresses. The river is flowing with clear water. Although, visibility can be lost during the afternoons if local miners are sluicing upstream (more on this follows).

During my visit, the river was ideal to sample using a 5-inch dredge. Productiondredging or volume sampling could easily be accomplished using 8-inch dredges or larger.

There are regular access-points to the river from the road along the river. And there are small villages along the road where local miners and other laborers or helpers and various services and supplies are available at relative low cost. Power and land-line telephone appear to be present along the entire road.

As the speedometer was not working on the vehicle that we were using, I did not get an exact mileage-count on the amount of river that is available to this project. But it is safe to say that there is at least a 20-mile stretch of readily-accessible gold-bearing river where local small-scale miners are actively recovering gold.

Our client has hired a local administrator from the main town along the river. The local administrator has arranged permission to temporarily set up a base camp in a vacant house which is owned by the government. The house and property are ideal for a base until other arrangements can be made. There is a small store and restaurant on the property. There is some storage. The house has several comfortable bedrooms, electric power, bathrooms and a dining room. The local cook does a good job. It is a comfortable setting. The base camp contains all of the basic structure needed to support a gold dredging project.

  

Local communities are generally Muslim. Friendly. I did not detect a single bad feeling from anyone during the entire time that I was on the river. There was actually a lot of friendly interest, because white folks are not often seen in these parts.Here is a video sequence I captured in a nearby, larger-sized community:

  

It will be important to be mindful of possible cultural differences, though. Any westerners brought in to assist with this project will need to be careful to not disrupt local tranquility. Hiring a good, local administrator will be important so that we can facilitate communication in a positive way. Interpreters will be important in key places where local labor is being directed or managed by outsiders.

Our client has done a great job putting the basic support structure in place.

My client is a mining engineer from Europe who settled in Sumatra and has devoted the past 20+ years locating and developing mineral opportunities there. We have worked together on several projects in the past, two which were located in Borneo (Indonesia), another in Cambodia.. He has been involved with numerous different types of projects which I will not go into here. He is very experienced at working in Sumatra. He understands the culture(s) and he speaks the languages.

One interesting thing at the moment is that my client has also recently located an important iron-ore discovery in the same area. He is in the process of quantifying the deposit with a company of consulting-geologists that are based out of Jakarta. I was fortunate to meet the Director of this consulting-group during my visit. They are doing exactly what we have in mind: They are mapping and certifying reserves of proven mineral deposits in a manner that the final documentation can be placed on a bankable balance sheet.

While pursuing the iron-ore program, my client observed that the locals along the river were actively sluicing for gold. So he asked me to come over for a look. This was my first trip to this particular area of Sumatra.

Local Mining Activity

I observed three different methods of active gold mining occurring along the river:

1. Panning gravels from the gravel bars alongside the river.

2. High-banking the river gravels from the gravel bars in and alongside the river (description follows).

3. Panning river gravels that are being extracted from the bottom of the active river by divers (referred to in this report as “dive-miners”).

I could also see the telltale signs of past high-banking activity in placer diggings alongside the river not far downstream of the main town. My client’s local administrator told me that he believes the richest area along the river is upstream of the main town. That portion of the river extends away from the main road. I did not get a look at it on this first visit. He says that gold nuggets as big as several kilograms in size have been found up there. But, because local miners have no means to deal with the larger boulders, they mostly do their mining further downriver where we saw them operating.

I observed a of dozen or so active panning operations along the edges of the river where locals are panning surface gravels.

  

I also observed around a dozen active high-banking projects. Most of these projects are being accomplished with the use of two motorized pumps. One pump is used to suck ground-water out of active excavations, lowering water levels so that workers can excavate bottom gravels. The other pump is used to create suction through a 4-inch PVC (plastic) suction pipe. Material is washed down to the intake-pipe at the bottom of the excavation, sucked up and directed through a primitive (very) sluice box that rests on stilts out of the water. These pumps allow gravel-material up to (approximately) 3-inches in size to be passed through the pump.

Local miners are building wing dams, which allow them access to gravel out in the active waterway.

Local miners are actively wing-damming (building a barrier to direct the water around an open excavation) around shallow places in the active river where they want to mine. They then pump the excess water out of open excavations, while processing gravels out of them. Whole teams of local miners (as many as 20+ people) are working together in these high-banking projects.

The downside is that tailings-water from some of the high-banking projects is allowed to flow back into the active waterway. This eliminates water visibility for some distance downstream. Depending upon where you go, underwater visibility can be lost by mid-afternoon. But even in those places, there remains an opportunity to do underwater work starting early in the morning – or possibly doing night operations with the use of flood lights from the surface. Or by dredging upstream from active high-banking operations.

Dive-miners on a floating platform

I also observed some mining activity where local divers are bringing up gravel from the bottom of the river and panning it at the surface. These divers do not have access to the right kind of air compressors for underwater breathing, so they are free-diving (holding their breath while diving down under the water) to excavate bottom-gravels from the active river. Because of this, their production-capability is severely limited. All of the dive-miners I observed were bringing gravels to the surface with the use of metal cooking pots.

As the purpose of my first visit to this river was to confirm the existence of potentially-viable gold deposits within the active river, these dive-miners are the ones we decided to spend some time with.

Local dive-miners carve their diving goggles out of hardwood or bone from some kind of big animal. Lenses are made from glass that is glued onto the goggles with epoxy. The goggles are attached to a diver’s face with a strap cut out of a piece of tire-inner tube rubber. There is no face-seal, and there is no way to equalize pressures inside the goggles. This creates a natural limit to how deep dive-miners can go beneath the water’s surface.

Nevertheless, local dive-miners are diving down to around three meters and bringing up gravel. And the gravel contains a lot of gold in proportion to the volume of gravel that is being processed. The local gold-buyer told us that around 5 kilograms of gold are being bought every day from local miners along this river. The going price is around $44 per gram. If the gold-buyer is telling the truth, that amounts to around $220,000 in gold.

To put this in perspective, a 10-inch dredge in experienced hands, with some underwater visibility, should be able to process about as much volume as all of the mining activity combined that I observed along the river.

All of the local miners we spoke with agreed that the richest gold is located in the deeper-water areas of the river where they are not able to reach using their methods. While divers can get underwater, they do not have the technology to excavate the deeper-gravel deposits that exist down there. A person can only get so much accomplished using a cooking pot on a breath of air!

So unless they are lucky enough to find rich deposits in the shallow spots along the edge of the river, existing technology available to local miners generally does not allow them access to the higher-grade areas located along the river-bottom. For the most part, local miners are working average gravels along the edges.

Confirmation

All of the images of the mining activity that were initially sent to me by my client showed high-banking activity that was taking place outside of the active river.

Sometimes, there can be high-grade deposits being mined alongside the river; but local conditions (deep gravel, dirty water, etc.) do not allow for a viable dredging opportunity within the active river. Therefore, the main purpose of my first visit to this area was to establish if there are high-grade gold deposits inside the active waterway, and to assesswhether or not we can perform a production dredging program there.

  

Approximately 5 miles downstream from the main town, we found a company of around ten local dive-miners who were swimming down to bring up gravel from an underwater excavation. We observed that they were recovering a substantial amount of gold in proportion to the small volume of gravel being processed. As this was an excavation project inside the active waterway, my client and I made a quick plan to complete our initial confirmation while working with this group of dive-miners.

After spending a little time getting to know these dive-miners, one of their leaders offered to take us on a short tour and show us some of the richer areas where they had done some dive-mining along the river. He showed us several places where he said their team-program had recovered as much as three ounces of gold per day at times. Each place he showed us was consistent with the types of areas where we find high-grade pay-streaks on the Klamath River in northern California.

According to our guide, the combinations of water-depth and/or gravel-depth usually prevent dive-miners from pursuing the richest deposits in the river.

  

This river is very similar to the rivers that we dredge in California. There are regular directional changes, a steady drop, and fast-water areas in the river, which create the natural diversity required to form high-grade pay-streaks. There is plenty of bedrock showing and deep water pools.

Our guide told us that the river gravels pay in gold-values starting from around a foot below the surface, all the way to the bedrock. He said the richest gold is often on the bedrock, and sometimes they can see gold inside the cracks when they are able to get down that far. He said that 1 and 2-gram gold nuggets are not uncommon. He said the biggest nugget he personally found was 10-grams (32.1 grams to the troy ounce).

In anticipation of the eventual need, several years ago, I shipped a T-80 air compressor, a dive-regulator and the required air-fittings over to this client in Sumatra from California. He arranged to mount the compressor with a small Honda motor. We brought that diving gear along with us on this trip.

So after getting to know our guide on the river, we volunteered to use the compressor to help his company of dive-miners excavate gravels from the deepest part of their ongoing excavation. I offered to allow them to keep all the gold we found, as long as we could buy it from them at the going price. They readily agreed. The purpose of this was to allow me the opportunity to get a direct look at the streambed conditions from which we would recover the gold, and to allow me to measure the amount of gravel that we would process so we could place a relative value on the raw material.

It did not take long to get me into the water, where with the use of a cooking pot as a digging tool, I started filling a wash-bucket with gravel from the bottom of their ongoing excavation. Filling up buckets with material underwater is a pretty slow process. It required three gold-panners to keep up with my progress.

The existing excavation from this company of dive-miners was pretty substantial, considering that progress was being accomplished using cooking pots while free-diving down to around three meters of water. They had worked down a face of bedrock along the edge of the river to around 6 or 7 feet into a semi-hard-packed streambed material. They had not yet reached where the bedrock bottomed-out (where the highest-grade material should be located). Even so, I did see some gold flakes in the bedrock along the face that they are following.

According to the dive-miners, they have been working that specific excavation for 2 months, and had so far recovered around 2 kilograms of gold ($80,000.00). To put the size in perspective, we could open an excavation that size in about half a day using a 10-inch dredge. Opening an excavation is much slower than continuing one that is already opened up. Conservatively, the local dive-miners had recovered 2 kilograms of gold in about 25% of a day’s ongoing production using a 10-inch suction dredge.

The local gold buyer weighed the gold recovered from our 20-bucket sample and offered to buy it for approximately $25.00 (US) in local currency based on the daily price of gold on April of 2005.

Since I was able to stay deep using the compressor, I extracted gravel from the bottom of the hole. I brought up 20 buckets of material, which were carefully panned by several helpers from the local mining team. In all, we recovered 1.1 grams (around $48.00) from my sample. This amounts to approximately $2.40 (US) per bucket at current gold prices. This was a typical medium-sized wash bucket. A single 5-inch dredge would excavate the volume of material contained in a wash-bucket in several seconds. A 10-inch dredge would scarf it up in the flash of an eye!

The thing that makes this so interesting is that the gravel I brought to the surface, for the most part, was material which had been sliding down into the bottom of the hole from the upper-side of the excavation. Although I did get some material that adjoined the bedrock on one side of the hole, I was forced mainly to extract gravel that was sliding down into the hole from further up in the excavation. The nature of scooping samples with a cooking pot underwater is that you take whatever you can get. Unlike dredging, you do not have an option to move top-material out of the way to get down to more productive stream layers located deeper in the river.

At the same time that I was taking samples from the deeper part of the excavation, the other dive-miners from the local company were bringing up samples from shallower streambed material. While I did not add it up, I did observe that their pans seemed to have just as much gold as we were getting from deeper in the hole. Most of the material I brought to the surface slid in from the shallower area where the other dive-miners were working.

While it still remains to be confirmed from a more organized sampling program using a suction dredge, this preliminary indication, along with the information given to us by these miners, indicates that the average gravels in this river almost certainly do contain commercial gold value.

More often, we are accustomed to finding that average river-bottom gravels carry non-commercial gold values, and that it is necessary to locate the high-grade gold deposits which usually form in the contact-zones between flood layers or on top of the bedrock. The existence of commercial gold-value in average gravels likely means that the pay-streaks will be even higher-grade.

We have confirmed that commercial gold deposits can potentially be dredged from this river. The next step is to follow up with a preliminary dredge sampling program.

Recommendations

First: I am suggesting to my client that he follow-up to see if exclusive commercial rights can be obtained for mining gold along this river. If so, I am advising him to arrange it as soon as possible. If the client is looking for a partner to develop the prospect, as long as the cost is reasonable, we can help arrange the financial resources to help pay for concession-rights.

Whether or not acquisition of exclusive rights (not excluding local mining activity) to develop the gold deposits along the river will affect the way we should proceed:

A. Quantification and marketing the proven reserves: If we can obtain the exclusive commercial rights, we should look hard at the concept of implementing a sampling program in concert with credible consulting-geologists to confirm and certify the existence of proven reserves. The purpose here would be to market the reserves to a larger public-traded mining company. In this event, we are prepared to help provide the funding and expertise to perform the sampling program. A good start would be to consider contracting with the same firm our client is using on the iron-ore project to perform the geological functions required to map and substantiate proven reserves.

B. Mining high-grade gold deposits: In the event that exclusive commercial rights on the river are not available, or a preliminary dredge-sampling survey convinces us that average reserves are not marketable, based upon what local miners are recovering from the river using primitive methods, it is a near certainty that money can be made using dredges to target high-grade gold deposits.

A preliminary dredge sampling program will be necessary whichever way we move forward with this project.

There would be several objectives in the preliminary dredge sampling program:
1. Determine if the average gold-values in the river will support a quantification program (outlined in A above) with the purpose of marketing proven reserves to a larger mining company.

2. Establish the value of high-grade deposits to get an idea how much money can be made from going right into commercial production.

3. Work out what recovery equipment will be needed to pursue either step A or B above.

4. Work out how we will harmonize a dredging program with local miners, general populations along the river, and others (government officials) who will take an interest in what we are doing.

It would be wise to allow no less than a month for the preliminary dredge sampling. To keep costs down until we confirm a commercial opportunity,if possible, I suggest we use the client’s existing structure as much as possible — meaning vehicles, local staff and the existing base camp.

To perform the preliminary sampling, we would need to hire several local dive-miners. I would like to choose them.

If possible, I would also like to hire an assistant/interpreter person who can stay with us throughout the project to help facilitate communication and coordination with locals. This might be someone that the existing geology-firm could provide. Having someone who is sincerely dedicated to projecting our intention and goodwill during the sampling project will go a long way to facilitate steady progress in the field.

Therefore, the next step is for us to find out:

A. Can we obtain exclusive commercial mining rights on the river? If so, at what cost?

B) Can we obtain permission to proceed with a suction dredge exploration program? If so, at what cost?

PumpsPumping systems used to support local high-banking operations.

If gaining permission to use a suction dredge is going to delay the project, we also have the option of proceeding with a system like what the locals are using in their high-banking operations. Just by adding an air compressor and an extended suction hose, we can adapt a sluicing operation (like what locals are using) to an underwater dredging program. In this case, we should allow a week to fabricate an improved recovery system. If we go this way, with just a little instruction, we can hire locals to do all or most of the work. So, for the most part, this would just be another local mining operation.

Having said that, using a floating dredge would be much more efficient for moving the gear around to each place that we want to sample. A 5-inch suction dredge in experienced hands will also out-produce one of those sluicing outfits about ten times over! Still, if necessary, we could get the preliminary sampling job accomplished using (for the most part) local equipment.

Dave McCracken
Underwater Mining Specialist

 

BY PAUL BADALI

Since we’re still in the mainstream of the dredging season, I’ve decided to share a few tricks I’ve picked up in my experiences with dredging over the past few years. Hopefully they will help to make your dredging a little easier.

After several seasons of use, dredge hose becomes cracked and needs to be replaced. I have tried to repair the cracks and holes in my 5-inch yellow hose with silicone R.T.V. glue, that didn’t work; so I knew I would be replacing it. The only 5-inch hose I could find in the dry desert state of Utah was a very light duct hose called Spirolite, which is used to blow insulation into attics. The hose is so light and thin that I decided both the first and second time I went in to purchase some it could not hold up under dredging conditions. But the price was so good (about $3.90/foot for 5-inch) that I finally bought a 10 foot length just to see how it would hold up in the Klamath River. I liked it so well that when Tony Dilmore, who had originally recommended it to me, showed up in Happy Camp with some, I bought another 20 foot length from him.

Spirolite has definite advantages in some dredging applications. First of all, it is extremely flexible. It is ideal for creek dredging where the hose often must be wrapped around boulders. Secondly, it is extremely lightweight weighing only about half what the yellow hose weighs, so it’s easier to pack down the bank or into remote dredging sights. It does not show excessive wear as I had feared it might. When I first looked at this hose, I pinched my thumb nail and finger nail together on the thin clear material between the spiraled ribs and was able to pinch a hole in it. But I can’t see any holes in my 20 foot section of hose after half a season’s use in the Klamath River. So, it seems to hold up well. It does develop small holes where it is clamped to the nozzle and the jet, but these areas are at the end of the hose and can easily be cut off when they get bad. And at $4/foot, you can afford to take this into account and buy five feet more than you need. And as for beating out plug-ups, you don’t have to. This hose is so flexible that it rarely plugs-up. If a rock does turn sideways and plug, you simply deform the hose with your hands, and the plug frees with no hammering on the hose!

There is one application where a heavier, stiffer hose is preferred over the Spirolite, and that is in deep or fast water. Because the hose is so light and flexible, the water can grab it and keep pulling it out of your hole. When I used this hose in the gut of the “Glory Hole” on the Klamath in about 15 feet of water, I had to keep the dredge near the edge of the river, use 30 feet of hose, and anchor it to the bottom at two points on the way out into the gut. The nozzle still washed out each time I went up to knock a plug out. But for calmer more shallow water, it’s the hose I prefer to use.

You should be able to get it at most large hose supply stores in larger cities. If they don’t recognize the brand name Spirolite, ask for the lightweight clear spiral duct hose they use to blow insulation into attics with, and get prices at three or four hose supplies. You may get it even cheaper than I did!

Has your swivel nozzle stopped swiveling after two seasons of use? Mine had. Sand and small rocks work their way down into the joint, and rust accumulates in there over the winter. But if you have access to an arc welder, the repair job is simple. Just cut or grind off the weld beads that hold the swivel joint to the nozzle, and remove the swivel joint. Inside you will find two rubber O-rings or pieces of rubber cord cut to work as O-rings. Pull the whole assembly apart, and use a wire brush to buff rust and sand off of all the metal parts. Clean the rubber cord or O-rings in water.

You want to catch any sand that falls out, and pan it. I found one nice flake of gold inside my nozzle when I cleaned it. You may wish to use some type of non-oil lubricant in the swivel joint before you reassemble it, such as graphite or silicone. I haven’t done this yet, but I suspect graphite is the way to go.

To reassemble, simply match the old ground-off beads back up, and tack it in the same spots with an arc-welder. I would not gas weld these beads, as I suspect it would get the rubber O-rings too hot and damage them. When you are done, your nozzle should swivel as good as new. While you have the welder in hand, touch up any wear you see elsewhere on the nozzle.

This last winter, I got about 26 feet of 36-inch-wide miner’s moss free! You may be able to do the same. I noticed that miner’s moss was used on the floor as mats in every entrance at a local high school. I found the janitor and asked if he would keep me in mind, and give me any old pieces he might be throwing out in the future. He was curious as to why I would want old mats, and we got into an hour’s discussion about dredging for gold. At the end of our chat, he said, “You know, I think we have a few old pieces we’re throwing out in a store room right now.”

We went to look, and he helped me wheel out three six-foot pieces, and one eight-foot piece of miner’s moss. They needed some cleaning up, but hanging the carpets on the kid’s swing set and using the garden hose soon took care of that.

The moral of this story is ASK. If you want something, ask. If you think people will say no, nine times out of 10, then just ask 10 people, and you’ll get what you want. Everyone has seen miner’s moss being used for foot mats. The U.S. Postal Department uses it, supermarkets do, banks do, etc. They all have to throw out the old and replace it with new. So ask for the old mats, and chances are you will get some!

I would also like to give some advice on moving your small-size dredge around on a big river like the Klamath. If you are not a good swimmer, and you are scared to death to swim across; then listen to your intuition, and stay on the side you’re already on. Know your own limits, and don’t get yourself into trouble. But, if you’re an average swimmer, and just a little apprehensive, then here are some tips on getting yourself, the dredge, gas supplies, and concentrates back and forth across the river without a boat.

Number one, buy a good set of fins. Good fins fit over your wet suit booties and are fairly stiff. They are not so stiff that they feel like cedar shingles, nor so soft that you can touch the tip of the fin to the heel, but somewhere in between. With a good set of fins, you have about as much power in your legs as a 2-hp outboard motor, and you can really cruise across that river! Always wear your wet suit without weights when crossing, and take it easy. If you’re not used to pumping fins, you can quickly get a leg cramp from over exertion.

The current will pull you downstream as you swim. Pick a calm stretch of river to swim across, and start way up stream from where you want to end up. Don’t choose a calm spot immediately above bad rapids, because if you don’t make it, you will be going for a very bouncy ride. If you are crazy like I am, this can be lots of fun, but it can also freak out your wife who watches the ride from shore!

To swim across, just float on your back, point yourself towards the other shore, and pump your legs. Don’t try to head up- stream and fight the current! Just start way upstream from where you want to land on the other side, and take a relaxed ride. The fins do all the pushing, just let your arms dangle. With fins and a wet suit on, it’s easy as swimming in a lake.

To take my dredge across, I load everything onto it, and push on the tail-end of the sluice box while kicking with my fins. I do not like a rope tied from the dredge to the shore. I do not swim a rope across first, and let that rope pull the dredge in. I play outboard motor with my fins, and I propel the dredge to the other bank. I lie on my stomach if pushing, or on my back if pulling. I feel much more in control of the dredge this way. I do choose a very calm stretch of river to do this, and I give myself twice the distance upstream that I think it will take to get across. It’s easy this way for one guy to get a dredge across by himself, and it’s a breeze if you have a helper also wearing fins.

Supplies and concentrates are also easy to get across. If you use a large 30-gallon tub to dump your concentrates into, you already own a small boat. You can put your weight belts, winch, tools, towels, etc. into the tub, and pull it with you as you lie on your back and kick across. It will sink if you tip it, and an inflated inner tube around the tub adds safety and more buoyancy. You can pull people in dry clothing across in a small rubber raft as fast or faster than they can paddle. You can also very easily swim a motorized sluice (high-banker) across the river in a small raft or an inner tube. You can fit lots more cargo in a rubber raft if there is no one in the boat! Obviously, when you want to come back across the river, you have to walk upstream; because you will be washed downstream as you swim back across.

There really isn’t much to fear from a big river if you are careful. You float like a cork in a wet suit. Don’t fight the current! The current is stronger than you are, so “go with the flow,” and let it work for you. Get good fins, so you have some push, and have a good time with it. In most cases, there has been less prospecting and mining done on the other side, so you may reap great rewards for your investment in a pair of good fins!

Good luck, and see you out there!

 
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This story first appeared in Gold & Treasure Hunter Magazine
Sep/Oct, 1996 on Page 14. This issue is still available! Click here.

By Dave McCracken

“Having the Gold Mining Adventure of a Lifetime!”

Dave & Alley

Author’s note: This story is dedicated to Alan Norton (Alley), the lead underwater mining specialist who participated in this project. Under very difficult conditions, Alan made most of the key dives which enabled us to make this a very successful venture. Alan lost part of his ear to a hungry fish one day; and the following day, Alan was making a key sampling dive again because we needed him to. There are very few people I know, if any, with more courage, dedication and enthusiasm to successfully complete a difficult mission than Alan.First came several Toyota Land Cruisers. Then, a couple of Isuzu Troopers, followed by a number of small pickup trucks. These were just in front of two large Russian troop carriers, all filled with armed troops. They came in on us fast, carrying along a big cloud of dust from the dirt road. Even before the vehicles came to a stop, soldiers were jumping out of trucks and running out to secure perimeter positions. They were carrying AK-47 machine guns, M-79 grenade launchers and Chinese rockets. I had seen these guys before. I had fought with them, and I had fought against them. They had that unmistakable look in their eyes. They would kill with little or no provocation.

Once the perimeter was secured, three generals stepped out of their Land Cruisers and enthusiastically approached us, their personal bodyguards close behind. The generals looked friendly. Their bodyguards looked seriously unfriendly! The generals, whom we had not met until now, hurried right up to me and each of my men and gave us big hugs, hand shakes and slaps on the back, like we were long lost sons. The bodyguards stood there with machine guns pointed in our general direction, doing what they were supposed to do to ward off any potential menacing threat to their leaders–which, by the way, never crossed our minds. We did the natural thing; we acted like long lost sons!

We had not been in Cambodia even for one hour before we were packed into Land Cruisers of our own and driven to Kampong Saom on the coast–which was almost half way across Cambodia. The end of the dry season had caused the water levels in the Mekong River to drop so low that deep-water ships were no longer delivering cargo to Cambodia’s capital, Phnom Penh. Therefore, it was necessary for us to go to Cambodia’s only other deep-water port in Kampong Saom to take delivery of five full ocean shipping containers of mining and additional equipment, supplies, boats and vehicles that had been shipped over there from America to support our project.

Since nothing happens immediately in Cambodia, we ended up spending about a week at a gorgeous beach while waiting for the shipping containers to be released by Cambodian Customs. Our hosts were taking good care of us. The hotel was comfortable, the beer was cold and the crab meat was freshly cooked on the beach–and it was all we could eat. In fact, we were just about getting bored. That’s when the generals showed up.

Isn’t it amazing how fast boredom can turn to fear? After hugs and handshakes, the generals agreed it was time for target practice. They had their bodyguards throwing beer cans out into the water so they could shoot at the cans. Pretty soon, lots of people were shooting at them. The few civilians that had been enjoying the beach scurried off quickly and respectfully. Everyone was laughing and having a good time except us. We were laughing, but not sure if we were going to be the next targets! It was all too much at once. We didn’t even know these people and they were all enthusiastically shooting their guns off. We were surrounded!

Pretty soon, one of the generals handed me some kind of machine gun I had never seen before and challenged me to shoot a fresh beer can. It was the only beer can remaining on the beach! This was a tough position for me to be in; those guys were not the best shots. I calculated whether I should try to out-shoot them, which might cause the generals a loss of face in front of their men, or to miss the can and perhaps lose their respect? On an impulse, I clicked the machine gun over to full automatic and fired a short burst to find a mark, adjusted slightly, and hit the can, knocking it up into the air on the second burst. No one had used automatic fire–probably to conserve bullets. All the generals burst out in a roar of laughter, followed by all their men. Deciding to quit while I was ahead, I handed the machine gun back to the general with the clip still half-full of bullets. That was the end of target practice and the beginning of my very warm friendship with that general. About a week later in Phnom Penh, this general and his very kind family, with great ceremony, adopted me as their number-one son.

The beach was just the beginning of 60 days of non-stop adventure which took me and three of my men from one end of Cambodia to the other in search of gold and valuable gems.

As it turned out, the generals were directly involved with this exploration project–which, by the way, was the first precious metal exploration project in Cambodia since the United Nations returned control of the country to a Cambodian coalition government in late 1991. During the course of the project, it became abundantly clear that our presence, and our successful venture, was very important to these generals and the Cambodian government. Cambodia is just getting back on its feet after decades of war and agony. The country is hungry for capital investment from the east and west. Successful ventures such as ours would help facilitate that.

Our project took place in northeastern Cambodia on one of the three main tributaries of the Mekong River. We were hired to help this operation put its suction dredging equipment into production and to help find high-grade mineral deposits.

The area is remote. In fact, it is the same area America bombed in the early 1970’s (with B-52’s) to prevent the Viet Cong from moving supplies on that portion of the Ho Chi Minh Trail. You just would not believe the number of bomb craters; I have never seen anything like it. In fact, up until the time of our project, I don’t believe a single bulldozer had visited that section of Cambodia since we bombed it! While these conditions probably never did slow down the Viet Cong very much, they certainly did slow us Americans down a lot! It took literally weeks for us to transport our equipment to the work-site. Trucks and trailers would disappear into craters and then come back out, one after the other, like a big roller coaster ride–only in slow motion–for hundreds of miles! It was one of the most amazing things I have ever seen!

All the while, our security troops were worried about being ambushed by Khmer Rouge rebels–roving bands which were still occasionally shooting up taxis, burning bridges, robbing various business establishments and causing other acts of terror around the countryside. Our generals were very concerned to make sure there were no embarrassments on this operation. Therefore, they sent along a 300-man military force to provide security. Each of us was also assigned several personal body guards. They also issued each of my men and me our own machine guns–which we gladly took. You kind of feel naked without a weapon when everyone else is walking around with some kind of heavy fire power! Here follows some video segments that I captured of our interaction with our bodyguards and some of the troops that were assigned to our project:

By the way, the people of Cambodia are the kindest-natured people I have ever associated with. Everyone is very polite and friendly. Unless it is worth dying over, you never see an argument in Cambodia! During the entire 60 days of our project, there was not a single person I smiled at that I did not receive a heartfelt and sincere smile in return. They seem to genuinely like Americans. In fact, any product or item that says Made in America is in great demand in Cambodia–especially hats and insignia which carry American flags and symbols.

One night, we had to make an emergency dash through rebel-held territory so that we could meet a production deadline. We were driving like madmen through bomb craters, up and down, with grenade launchers and machine guns hanging out windows. Our security people were very concerned we would be ambushed. Better to be safe than sorry, I suppose. But, I never saw any direct sign of danger. Even so, the eminent concern–with guns and grenades pointed out windows, with everyone on moment-to-moment alert–created a charged atmosphere which we usually only experience on television in America.

We received incredible hospitality from native villagers in every community that we passed through or stopped to visit. Many villagers had never seen white men before. You have to remember that Cambodia, for the most part, lost an entire generation of people to the Khmer Rouge regime. Locals told us the ratio of women to men in Cambodia is five to one, because the men were either killed in war or murdered. That ratio is about how it appeared to me.

The equipment we sent there to use for sampling took a very heavy beating during the trip across Cambodia. The axles we mounted on the dredge platforms were badly bent from being dragged through hundreds of craters, and there was quite a lot of other damage, too. So we found ourselves staged for about a week in the last town before we would reach the river. This was a place where various supplies and services were still available. There, my men and I supervised final repairs and preparations for our sampling program. It is very challenging to do this sort of thing in an environment where most of your helpers do not think the same as you do, and do not speak any of your language:

Between the delays at Customs, the painstaking trip across war-torn Cambodia with the equipment, and the time we had to spend repairing gear at the final staging area, we only had about 2 weeks remaining to accomplish what we went to Cambodia for in the first place. A final distance to the river of 35 kilometers does not sound like very far; but in Cambodia, where anything and everything can go wrong; this last 22 miles still seemed like a long way to go. Even so, there was a lot of excitement when we had everything ready and began our final journey to the river from the last bit of civilization that we would see. The following video segments demonstrate the excitement that we were all feeling to finally get started on our dredge sampling program:

Along the way to the river, we started seeing lots of diggings alongside the road. We thought the holes were water wells at first, because they were perfectly round and uniformly about 2 ½ feet in diameter. Then we realized they must have been something else, because there were so many, and they were positioned so closely together. We stopped to take a look as soon as we saw some locals actively working inside one of the holes. These turned out to be sapphire miners! They were digging about 10 meters down to bedrock and recovering handfuls of pretty blue stones from the bottom gravels. These miners were selling their gemstones for mere pennies (Me and my guys were buying!). We found out these miners were from the Cambodian hill tribes; jungle dwellers that pretty-much are the same as they have been for hundreds or thousands of years. A number of humanitarian groups are now present in Cambodia attempting to prevent the modern world from impacting too dramatically upon these ancient tribal people. The following video segment captured some dialog that we had with a few of the sapphire miners. It presents a good example of how simple and kind the people are from the Cambodian hill tribes:

Immediately upon our arrival at the river, we realized that we had 2 serious problems to overcome. The first was that there was about a 10-meter drop from the bank down to the active river. There was no ramp or other simple way to launch the 10-inch dredge and special recovery platform that we brought with us for this job. Not wanting to use our security force for this, we immediately set out to hire around 30 men from the local hill tribe village to dig a ramp. That exercise took about 6 days to accomplish. So we were not going to have use of the big dredge until the final week of our project.

Our second serious problem was that the (sizable) river water was running mud-brown. We did not know it at the time, but there was some active dam construction happening upstream in Vietnam. The ongoing construction was turning the river to mud-water. That meant that we were not going to have any visibility underwater. There is a way to get the work done in dirty water; but besides the serious safety problems associated with dredging blind on the bottom of deep tropical rivers, you have to do everything by feel. This slows you down to just a fraction of what you can accomplish with some underwater visibility. This was going to be a difficult mission to accomplish!

All travel on the river from our base camp had to be accomplished by boat. The boat that we arranged broke down on our first trip downriver to survey the area. As it was just before dark on our return to camp, and the mechanical problem seemed pretty serious, we actually started making plans to sleep on a sand bar that was located out in the middle of the river, maybe 5 miles away from our camp. With no dinner and no shelter from the mosquitoes, it was a pretty bleak feeling out there. I captured the following video segment just as our guide was suggesting that we spend the night there on the sand bar. Fortunately, they got the boat motor operating just as darkness was almost complete. It sure felt good to finally arrive back at camp that night where there was a hot meal and perfectly good tent waiting for each of us:

While we were doing our initial survey downriver, we came upon a local river mining operation that was using a long-handled (about 15 feet long) shovel, suspended by a floating platform made of bamboo. This dredge was being used to excavate sand off the bottom of the river. The locals called this a “Vietnam dredge,” because the river mining technology had been imported by miners across the border in Vietnam. Almost the entire dredge was made out of materials from the jungle. Even the lines being used to tie off the dredge out in the river were made from jungle vines. The only part of the dredge we could see that was from our modern world was the head of the shovel. That looked to be fashioned from the car hood of a bombed-out jeep. This river location was part of the Ho Chi Minh trail. So there were plenty of bombed-out jeeps around, and some ruined Vietnamese tanks, too. In fact, there was a lot of painful history here!

Author and several team-members trying out a “Vietnam Dredge,” made from bamboo, which local miners use to bring gold off the bottom of the river.

Upon discovery of the local river mining program, we immediately took the opportunity to make friends with the local miners and the elders of their village. This is standard procedure anytime we are performing an preliminary evaluation in a new area. While their methods might sometimes be somewhat primitive compared to ours, I have found more often than not that hundreds (or thousands) of years of local mining experience has given the miners who occupy an area a strong perception of where the richest gold areas are located. We did not have much time remaining to make a rich discovery for our clients. Any head start the locals could give us would surely be a welcome development! Ultimately, the locals told us that their dredge was positioned along the strongest line of gold that they knew of in the river. That was a big help!

To get an idea of how much gold they were talking about, we accepted their invitation to go down and operate their Vietnamese dredge for a little while. The following video segment captured my guys running the local production equipment. It worked by pushing the shovel down into the sand, and then using a make-shift windless to raise the river-bottom material to the surface. There, local wooden gold pans were used to process the material:

While the local miners were recovering a fair amount of gold from the river-bottom sand deposits, their success did not appear to help us very much. This was because we wanted to sample for the high-grade gold deposits which are almost always located at the bottom of hard-packed streambed layers. In working their Vietnamese dredge for awhile, it did not take very long for us to realize that the long-handled shovel would not penetrate the hard-packed streambed material that was under the sand. Too bad!

5″ Pro-Mack Sampling Dredge

Still, knowing where local miners were supporting their villages with gold from the river gave us a starting point. The following day, we moved two 5-inch special sampling dredges onto the river some distance downstream from where the locals were mining, but directly in line with them so that we had a better chance of sampling on the strongest path of gold in the river

My guys were initially quite challenged by going down into the pitch blackness along the bottom of a muddy, tropical river. Because there is zero visibility down there, everything must be done by feel. This is not easy to do, because your imagination cranks up into overdrive about what might be lingering around down there to bite or eat you in the dark. Remember those horrific nightmares you had when you were a kid? That stuff doesn’t ever go away. The terror is still present; it is just buried. Going by yourself down to the bottom of a tropical river in total darkness, and having to feel your way around to figure out what is down there, energizes all you nightmarish fears right back to the surface. It is difficult to do what you are supposed to do down there with all this internal fear playing out inside of you! It takes courage and a lot of discipline.

So my guys challenged themselves with acquiring some preliminary sample results using the 5-inch dredges, while I was pulling the 10-inch dredge together and installing a special shaker table in the base camp that we would be needing to process large samples. The table needed to be anchored in concrete. All of this took several days. Time was running out!

On the second day of sampling, our lead diver, Alley Norton, touched down in some hard-pack and came up with a pretty good showing of gold. The following day, I encouraged Ally to go back down and open up the hole (get a bigger sample). We had to keep dredgers separated while sampling, to avoid someone getting smacked with a cobble being tossed in the dark. There simply is no way to tell where anyone else is when you are dredging in muddy water. Alley’s hard work and enthusiasm paid off. Considering how small his sample actually was because of the dirty water, he recovered a lot of gold! We had located high-grade!

I captured these following video segments towards the end of the third day of sampling:

As we had less than a week remaining to accomplish our mission, we all focused the next several days placing the 10-inch dredge and platform into the water. The local help had completed our launch ramp according to plan. Wow, was that a lot of work! Once the big dredge and recovery system were floating in the river, we still had to dial it all in to get it working right. This was particularly important with the sophisticated recovery system that we had brought along for this job.

Before opening up Alley’s discovery with a production sample, we needed to make sure the recovery system was working right. This all took another two days, because the large volume of sand from the bottom of the river was overwhelming the gravel pump that was supposed to transfer classified material to the recovery system. This problem required us to get very creative in the middle of the jungle. Through some trial and error, we constructed several water blasters to inject water into the feed of the gravel pump. This made sure that enough water was going into the feed to keep sand from packing up in there. While all of this took up valuable time, we had to get the big dredging system fully functioning before using it to perform the final production samples in Alley’s rich discovery

We only had 2 days remaining on the project when we finally floated the big dredge over Alley’s rich discovery. Talking about racing against the clock! So while Alley went down in 6 meters of underwater darkness to suck up the sample, I stayed up on deck to fine tune the dredge’s recovery system. You can only put one diver down on a big, powerful dredge in dark water. So our other guys helped where it was needed. Alley spent several hours opening up a large hole through about 2 meters of loose sand. Our plan was to first pump most of the sand off the hard-packed streambed material where Alley had found the gold. Then we were planning to flush the sand completely out of the recovery system before dredging up the pay-dirt. This was to minimize gold losses because of too much sand overwhelming the system at once.

We were making good progress on our plan. But about half way through the day, Alley climbed back onto the dredge with a lot of blood flowing down the right side of his head and face. A pretty sizable chunk of his right ear was missing and it was bleeding profusely! Blood was actually squirting out with the pulse of his heart! He said while operating the dredge’s suction nozzle on the bottom of the river, it felt like a submerged log with rough bark brushed by his head, scraping his ear. When he reached up to touch where the pain was coming from, he could feel that a part of his ear was gone. That’s when he came to the surface. Seeing all that blood and the bite out of Alley’s ear was very dramatic for everyone that was present.

Back at camp, we bandaged Alley up as best we could. We always bring a substantial medical kit with us on these projects. We applied antibiotics just to be safe. Alley said the pain was not too bad. He was mostly worried about how ugly it was all going to look later. I would have been worried about that, too! There wasn’t anything else we were going to do about that situation out in the jungle, though. So we decided to set aside that problem for another time. We were going to depart Cambodia in a few days, anyway.

Collectively, my guys and I decided it was wise to not do any more diving in the river until we found out what bit Alley. Whatever it was, there was a chance that we could still salvage the sampling project by wearing more protective gear while underwater. We still had one more day available to perform a final production sample!

As none of our bodyguards or the other military guys in camp seemed to have any idea what bit Alley, we decided to drive the motor boat up to the hill tribe village where the Vietnamese dredge was operating. We had already made friends with the villagers and elders there. Once there, we removed the bandage from Alley’s ear to show the elders, and they immediately knew what bit him. They told us that there is a fresh water blow fish that lives on clams at the bottom of the river. Apparently, this type of fish must have come alongside Alan’s head; and in the very poor visibility, thought his ear was a clam. One bite and there it went. The villagers assured us we would have no further problem with that fish if we started wearing hoods, gloves and full face helmets in the river while it was muddy.

Afterwards, we heard the story of one of our military men bathing naked in the river and losing his vital organ. Apparently, the man had just been married several weeks before. Luckily, we had been taking our showers up on the bank!

When we arrived at their village, the local people were busy preparing for a “grand celebration” that was to take place that evening. All of us were invited to attend, and it would have been impolite for us to decline their kind hospitality. The celebration turned out to be a funeral ceremony for one of their important elders who had died 3 years before. I have seen similar traditions in Madagascar, where the big celebration of someone’s life happens by the whole village several years after the person dies. These hill tribe people were busy decorating a whole shrine that would be dedicated to the person, carving all sorts of symbols relating to the important things the person lived through. Interestingly, the biggest symbols I recognized were American military helicopters and B-52 bombers. No doubt, the later part of the Vietnam war must have been a very traumatic time for these very simple hill tribe villages, with the Viet Cong using their river for a highway, and the Americans dropping thousands of tons of bombs all around.

These people seemed nothing but pleased to have us Americans present, so we accepted their invitation to participate in their party that evening. Indeed, the party turned out to be one of the most interesting events I have ever been part of. A center covered circle had been built for the people who wanted to express their grief over the loss of a loved one. Inside that area, there were around 20 people who were crying and almost howling in deep grief. Outside the circle, the rest of the village paraded round and round in a dance in joyous celebration of the person’s life.

My guys and I jumped in with the outer group. They were beating on different-sounding chimes to make their traditional music. The sound was so interesting that I captured it on tape. The occasion was something I am sure that none of us will ever forget. We were honored that they allowed us to participate in such an important tribal event. They were honored that we joined in with them. It was a wonderful bonding experience between us and remote villagers of the deep jungles of Cambodia. The following video segment and audio segment capture some of our hill tribe friends as they were preparing for the party, and then capture some of the music and feelings that we shared together that evening:

Hill Tribe Music:

The following morning found our team back on the 10-inch dredge, preparing to perform one last production sample. This was our last day to accomplish what we went there to do. So much effort and money had been invested to transport this fantastic equipment halfway across the world, through some of the most difficult circumstances on the planet; only to finally arrive on our last day right over top of what appeared to be a very rich gold deposit.

It was so important that we get the best possible production sample, Alley insisted that he take the first dive. He had started the sample on the previous morning, so he knew the layout of the hole in the total darkness of the river bottom. Total darkness down there would have required either of my other two guys to spend valuable time figuring out what Ally had already done. As this gold deposit was really Ally’s personal discovery, we agreed that he would take the first dive of the day to open up his hole. I would spend that time dialing in the recovery system as well as I could. Then I would finish the sample during the afternoon with a second long dive. My other two guys were content to support us from the surface. I don’t think they were quite over the emotional shock of Alley’s blood and guts from the day before. Who could blame them?

As I knew this would be a memorable occasion that none of us would ever forget, I captured some video of Alley bravely overcoming his fears and going back down into the deep black hole that attacked him on the previous day, something very few people would do. You will see from the following video segments how good the production dredging equipment was that we managed to place on top of that rich gold deposit. I believe the recovery system was the most sophisticated that had ever been used with a suction dredge up until that time. It was truly a miracle that we ever got the equipment there, or that we found such a high-grade gold deposit under those difficult conditions. With all that we had been through, in my world, there was no other choice but to perform that final production sample:

After a few hours of diving, Alley came to the surface; because his ear was throbbing in so much pain, that he said he could no longer focus on what needed to be done on the bottom of the river. By then, the recovery system was dialed in as well as we were going to get it. So I suited-up and went down into Alley’s deep, black hole. This was actually my first dive on this entire project. During the week or so that we had been on the river, there were just too many other things that needed to be accomplished which only I could do to bring everything together in time for this final production sample. So there I was, taking the last and most important dive of the whole project!

I will never forget in military jump school, the first time I bailed out of an airplane. It was one of those situations where I really did not have much of a choice. But looking way down there at the ground made jumping feel totally wrong. My body did not want to do it. So it was necessary for me to flick some internal emotional switch, override my natural instincts, and just force the body to make the jump. Going down into deep muddy water is much the same; the body does not want to do it!

I have actually done quite a few dredging projects where it has been necessary to perform the underwater work in muddy water. It is never easy! Especially when the water is deep! It was around 6 meters just to the bottom of this dirty river. That is a long way to go down in the dark. I worked my way down there slowly by following the suction hose, which is where I knew that Alley had left off. When I reached the suction nozzle, I rotated my body around it in a circle, feeling around with my legs and feet to try and find Alley’s dredge hole. Letting go of the nozzle was something I was not prepared to do, because it was the only thing that gave me a reference point down there in the total darkness. Also, feeling around tentatively with steel-tipped work boots felt safer than reaching out in the dark with my hands!

I soon found that Alley’s hole was just off to one side of the nozzle. Experienced dredger that he is, Alley knew better than to leave an unattended suction nozzle down inside of a dredge hole in the sand. The walls never stop sliding in on sand-excavations or loose gravel. If you leave a suction nozzle down inside of one, within just a short time, the suction nozzle and hose will be overwhelmed and buried. That would have been the end of this project. There was not enough time remaining to dig a hose out of the sand in the dark!

Once I found Alley’s hole, I memorized where the suction nozzle was positioned several feet away, and then I followed the edge of the hole all the way around to get some idea how big it was. This was the hard part, because it meant that I had to reach out and feel everything with my hands. All that blood pouring down the side of Alley’s face the day before was vividly on my mind! There were creatures down there with serious teeth! Here is where I had to flick another fear-switch off and just do the work. These fear switches are not really turned off. They are just suspended. I speak from bad experience. Depending upon how many of your internal fear-switches are in suspension, it just takes one small event to turn them all back on into nightmarish panic and terror. I have been there. It is not fun!

Reaching out meant feeling out as far as I could outside the outer edge of Alley’s hole to make sure there were no boulders up there that would roll in on me in the dark. I did not find any. Slowly but surely, I explored all of Alley’s hole by feel. It was pretty big; maybe 30 feet in diameter at the surface, funneling down to a center point about 2 meters deep. Alley had pumped a lot of sand! Before I went down, he told me that he touched down on the hard-pack streambed at the bottom of his hole, but that the sand kept sliding in on him. So he had not been able to get a sample of the hard-pack, yet. This was for me to do!

I invested about 2 hours into taking a sizable cut off the front and one side of Alley’s hole, working the sand back step-by-step in the darkness. I wanted to uncover enough surface area of the hard-pack as possible. This was so that further sand-slides would not prevent me from getting a good sample of the hard-pack. With time, I started uncovering the hard-pack. This is where the loose sand met the cobbles, boulders and gravel that were tightly compacted together. Though I could not see it, it felt just like the hard-pack we dredge along our properties in California.

While the dredge was plenty powerful enough to pull apart the compacted streambed material, my progress was slow. This is because I could not see the oversized rocks that had to be moved out of the way, and I could not put my hands out in front of the nozzle in the dark without getting them hurtfully banged up. Mainly, I just poked around down there in the dark to suck up anything that would go up the nozzle. Each time a loose cobble would block the nozzle opening, I would wrestle it off and put it behind me. It was not long before I had more loose cobbles behind me than I could manage. It was too far to throw them out of the hole, and trying to pack them out would have caused more sand to slide in. So I just juggled everything around down there the best I could, determined to get as much of that hard-pack up the nozzle as possible. Ultimately, my progress became overwhelmed by loose cobbles in the hole and sand sliding in from the sides. I had not reached bedrock, but I did get a fair sample of the material that Alley had touched down upon with the 5-inch dredge several days before. By my measurements in the dark, I estimate that I sampled less than a cubic meter of hard-packed material. That was all we were going to get under those difficult circumstances. It was a good feeling to finish what we had traveled so far to do.

The guys turned the dredge down when I reached the surface. I had to wait at the ladder for the longest time to allow my eyes to adjust to the bright sunny day. As I was waiting, my guys were making a lot of enthusiastic noise about visible gold in the recovery system. When I finally was able to see again, I climbed up onto the dredge to see that the entire recovery system was inundated with a thick layer of small golden flakes. It was, by far, the most gold I have ever seen recovered out of such a small volume of gravel. This place was rich!

We had just enough time before dark to run our concentrates over the shaker table back at camp. Everyone there experienced an incredible feeling of pride. Under very difficult circumstances, against all odds, we stuck it out right until the last hour to make this project a success. Watching all that rich gold flow across the shaker table had all of us in awe about how rich this river is. Who would have ever guessed? Right there on the Ho Chi Minh trail! While I am sorry to have missed capturing the gold-laden recovery system on the dredge, I was able to recover myself enough to capture the following video segment of the final clean-up. To put it in perspective, our small sample caused that shaker table to flow gold like that for a full 15 minutes!

We returned to civilization the following morning, and departed Cambodia a few days later.

Follow ups:

A short time later, our clients met with some serious misfortune by aligning themselves with the losing side in a power struggle over who would control the government in Cambodia. While they survived the events, they have been banned from the country forever.

Shortly after my clients found themselves in big trouble, all of the equipment and supplies we sent over (that they paid for in advance) were taken away. The only thing remaining there today that shows we were ever even present is part of a steel frame from one of the large floatation platforms. Everything else is long gone.

The wars in Cambodia are now long over. The people there are very friendly. You do not see guns there anymore. People are focused on getting ahead in business. They want to be like America. The government is trying hard to attract foreign investment.

Nothing since our project has been done to develop the deposit that we located. Although the government of Cambodia has offered to make an exploration license available, I have yet to raise the high-risk capital necessary to go back over and do something about what we found

I made a special trip back to the site of our discovery 2 years ago. The bad roads have been replaced with a highway! Schools have been built in the village communities. The people out there were happy to see me. Most importantly, dam construction in Viet Nam was finished and the river was running clear!

While I was out there, I hired a local boat to take me downriver to see if anyone was doing anything with our deposit. Nobody was there. Even the Viet Nam dredges were gone! It appears that my guys and I were the only ones whoever really understood the significance of what we found there. Local miners cannot access the rich material using their technology. With clear water, we could process hundreds of times more hard-pack in a day than what I sampled down there in the dark.

The following video segment was taken in the very place where the earlier segment showed us operating the dredge:

Alley and his brother are now managing a successful concrete business in Phoenix, Arizona. He never did anything to fix the bite out of his ear. Now he says the tattered look gives him personality and character. Since nobody will believe he had his ear nearly bitten off by a clam-eating fish while prospecting for gold at the bottom of a muddy river in the jungles of Cambodia in the middle of a war along the ancient Ho Chi Minh trail, he now just tells people that his ear was bitten off by someone while fighting in a bar on the north side of Phoenix. That’s already more adventure than most people can handle!

Note: This story was pulled together from the non-proprietary portion of an initial report from a preliminary evaluation of a potential production dredging project in Northeastern Cambodia. The opportunity to do something with this prospect still exists.

 

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