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By Dave McCracken

“It is vital that you design your recovery systems from the beginning to make certain they will actually do the job!”

Dave Mack
 

 Rubies and sapphires from Cambodia.

Over the many years, my various partners and I have experimented a lot with secondary recovery systems to catch fine gold and gemstones that get sucked up the suction nozzle of a floating dredge. There are numerous issues involved, each which must be carefully resolved to make it all work out right. I strongly advise you to study these issues for yourself as much as possible before deciding how to acquire accurate samples, and what to do for a production dredge if you decide to move forward with a mining program.

If these problems are not carefully considered and resolved in the construction of the equipment, the problems will definitely have to be dealt with in the field, where it becomes much more difficult to fix them!

Since the purpose of sampling is to accurately determine the real value of gold (and/or gemstones) in the river gravels, it is important how you acquire the samples. And if the samples turn out well, it is vital that you design your production dredge and recovery system from the beginning, to make certain they will actually do the job. The reason I stress this point so strenuously is because my team has been called in so many times to help with projects that did not acquire equipment that would efficiently recover fine gold and/or gemstones in the first place.

I also advise you to please not take for granted that gemstone-dredges advertised by various dredge-builders within the industry will recover diamonds or other gemstones efficiently just because the builders advertise that they do. I encourage you to review the points that I will outline here. Then you will have a foundation of understanding from which to ask questions and make your own judgments at the time when you will need to make pivotal decisions.

Gemstones are not heavy like gold. Therefore, they are much more difficult to recover.

Conditions must be set up to near-perfection to effectively recover gemstones from the volume of sand and gravel which passes through a dredge nozzle. This is especially true of production dredges in the hands of experienced operators!

Any enquiry into gemstone-recovery on suction dredges should certainly lead you to the subject of “mineral jigs”. A mineral-jig is a mechanical device that can be adjusted to create a specific suspended medium inside. As raw material flows into a jig which has been set up properly, different minerals are separated according to their specific gravity. Minerals that are lighter than a specific weight-range are allowed to flow off the top of the jig as tailings. Minerals that are heavier are allowed to settle to the bed, or to the bottom of the jig. The heaviest finer-sized materials (mostly gold and iron) are allowed to (flow) bleed out the bottom of the jig to keep it from concentrating with heavy material. Heavier materials are then collected elsewhere, or are directed to even more finely-tuned recovery systems.

The following video segment will demonstrate a mechanical suspension medium that can be created by a mineral jig:

Any and every enquiry into suction dredges and jigs should prompt a series of important questions:

1) classify and separate the smaller-sized raw material that is sucked up through the dredge’s suction nozzle?

2) What size-classification and how much volume of material will feed the jig?

3) How much volume and velocity of water will be included with the feed to the jig?

4) What will you do with the heavier material that is bled from the bottom of the jig?

Let’s please take these important questions up one at a time:

1) Classification: You cannot direct large-sized materials (rocks) into a mineral jig and expect it to perform well. This is actually true of any recovery system being set up to recover gemstones or fine-sized gold. Some method of screening is necessary to “classify” the size-range of materials that you want to direct into each type of recovery system. The more that different size-fractions of material are separated from each other, the easier it is to separate gold or gemstones from the other materials by their differences in weight.

Since dredges have limited space to work with (usually on a floatation platform or two), classification systems must be kept reasonably simple and portable.

Most suction dredges are set up with a fixed (not mechanical) classification screen which material and water flow across inside the sluice box. Riffles and various types of traps are constructed below the screen to trap gold and other valuable minerals out of the flow of water. All of the material that passes over top of the classification screen, or that is not trapped by the riffles under the screen, is allowed to flow out of the box and be discarded as tailings. For lack of a better term, let’s call this a “hydraulic classification and recovery system,” because it depends entirely upon water-flow to move raw material across the classification screen and through the riffles. This is the type of system that you can expect to receive as standard dredging equipment on today’s market.

Hydraulic classification and recovery systems have evolved over the years to the point where they generally recover gold and platinum with a reasonable degree of efficiency down to size-fractions relatively small in size. How fine in size depends upon various factors, like the purity of the gold, its average shape (round, flat or crystalline), and the nature of the material (slurry) that is flowing through the recovery system along with the gold or platinum.

It is reasonably safe to say that any recovery system is efficient down to a certain size-fraction of gold or platinum in any given area. The size-fraction might vary from one place to another. The reason for this is that the specific gravity of gold and platinum is generally 5 to 6 times greater than the average of other materials which commonly exist within a streambed. This incredible difference in weight will generally allow pieces of the heavier metal to penetrate the screen and drop behind the riffles in a sluice box – even though there is a strong force of water present to wash larger-sized material (rocks) over top of the screen.

It is also reasonably safe to say that the smaller a piece of heavy metal is (gold or platinum), the more it will be influenced by the fast, turbulent flow of water that is required to wash larger-sized material through a sluice box. For example, it requires a violent force of water to wash 9-inch rocks over top of a screen in the recovery system of a 10-inch dredge. So the smaller it is, the less likely that a piece of gold will drop through a hydraulic screen and get trapped behind a fixed riffle. Therefore, hydraulic classification and recovery systems lose efficiency as the particle-size of a heavy metal becomes smaller.


It is important to understand this: Because gemstones are only slightly heavier than quartz, and are within a similar weight-range as the average materials generally found in a streambed, hydraulic classification systems on dredges are not an efficient method of sizing raw material. This means that probably more gemstones wash across the top of a stationary classification screen (into tailings), than drop through it into the recovery system.

Furthermore, hydraulic recovery systems (fixed riffles and baffles) are actually designed to discard gemstones.

Because gemstones are light, it is unreasonable to expect them to drop through a classification screen that has a torrent of water passing over top. And then, because riffles will quickly accumulate a concentrate of material behind them that is heavier than the average specific gravity of a gemstone, you should not expect to recover gemstones efficiently using fixed riffles.

As far as I know, Pro-Mack is the only dredge-builder that has accomplished mechanical classification on a suction dredge. We do it by placing a shaker-screen (powered by a hydraulic pump) in place of the sluice box. Raw material from the suction nozzle is directed onto the shaker-screen. Minus-size raw streambed materials drop into a hopper under the screen and are then pumped to a recovery system – usually on a second platform. The following two video segments demonstrate this very important principle:

Summary: On suction dredges, there are basically 2 kinds of classification systems:

(A) A fixed screen which a flow of raw material is washed across by the force of water, with some portion of minus-sized raw streambed material dropping through. This system works relatively well on heavy metals down to a certain size-fraction. Efficiency is lost below that size, and there is poor efficiency on gemstones (they are too light).

(B) Mechanical classification, when set up properly, can be depended-upon to provide nearly 100% of the size-fraction that you want to separate out from the raw material, then to be directed into a recovery system. Please take a look at the following free video segment to see how we recently worked this out on a Pro-Mack commercial dredge system that is being used on a diamond recovery project in India:

Since it is impractical to refit smaller-sized dredges (which must remain portable for sampling) with mechanical classification, here is a substantial explanation of the system which we have developed to effectively recover more fine gold on our conventional suction dredges. It combines two classification screens to more-effectively separate material-feed into three size-fractions, each which is directed into a different recovery system. The smallest gold particles (which are most difficult to recover) are directed into low-profile riffles along the bottom of the sluice box which have long been proven to be very effective at trapping fine gold.

2) Size and volume: Jigs are available in different types and sizes. Generally, a certain size of jig is designed to process a given volume of material. Each manufacturer will have their own set of guidelines.

I say “guidelines” because there are variables that will change from one location to the next. The main consideration is the difference in weight between the mineral you are trying to save, and the medium that it is mixed with.

For example, because the weight-difference is so great, it is relatively easy to drop a particle of gold (19.6 times heavier than water) through a suspended medium of pre-sized quartz crystals (only 3 times heavier than water), because the difference in weight is more than 6 times. Therefore, with heavy metals, there is greater margin to introduce a larger variation of size-fraction (different sized material) into the jig, or a larger volume of pre-sized raw material, without forfeiting recovery.

If you are trying to drop gold particles through a raw material made up of iron (8 times heavier than water), you will be required to tighten-up the sizing and slow down the feed to the jig. This is because the weight-difference between what you want to retain and what you want to discard is only around 2 ½ times.

Sizing and volume are critical in the recovery of gemstones (usually only around 3.5 times heavier than water), because there will be only the smallest weight-difference between the valued material and the other streambed materials which must be rejected by the recovery system.

Summary: Sizing and volume requirements for jigs are largely affected by the difference in weight between the type of material you are trying to recover, and the raw material you want to discard as tailings. This becomes critical as you try and recover gemstones with efficiency.

3) Water feed: Most suction dredges operate on a “venturi” system, where a stream of high-pressure water is pumped into a power-jet at an angle to create a vacuum through the suction hose and nozzle. In this way, gravel and rocks can be sucked up from the bottom of the river and directed to a screening or recovery system floating at the surface, without having to pass them through a water pump. This allows a suction dredge to be manufactured at a small fraction of the cost to produce a dredge of the same size which must pass rocks and material through a pump.

But venturi-dredges are limited, in that they cannot lift streambed material and water more than about a foot (or less) above the water’s surface. Therefore, anything that is going to initially be done to raw material excavated by a suction dredge must be accomplished directly at the water’s surface. This is the reason why almost all standard suction dredges are equipped with hydraulic classification and recovery systems; because there is very little room at the water’s surface to do much else.


Men installing the Catch-hopper which mounts under the shaker-screen on a 10-inch commercial Pro-Mack dredge.

 

Classification systems used on a suction dredge almost always drop the minus-sized gravels into a sump or hopper that is located below the water’s surface. Therefore, to get the classified material up into a recovery system, it will need to be pumped.

Any jig is designed to allow only so much water-flow with the feed. The reason is that too much water velocity can wash sized-material across the top of the jig before the suspended medium has an opportunity to place particles where they should go.

Water-flow through a jig is highly critical in the recovery of gemstones because they are so light.

Therefore, important consideration must be given to how classified materials will be directed into the feed of a jig. We use hydraulic-powered gravel pumps on the Pro-Mack design, because we have found that venturi-elevators (using a high-pressure water flow) usually deliver too much water volume with the feed. For example, check out the water and raw material feed into the rougher jig (Preliminary jig) on one of the commercial dredges we were operating in the following video segment:

4) Bleeding off the heavy material: One of the reasons why jigs work so well, is that they are allowed to keep bleeding off the heaviest materials from the bottom. These otherwise would accumulate inside the jig and alter the suspended medium which creates the desired separation of your target-mineral from the other streambed materials. For example, if your target mineral is an average weight of 3.5 (times the weight of water), you must bleed enough heavy material from the bottom of the jig to maintain a suspended medium that is lighter than 3.5. Get the idea? If the suspended medium in the recovery system is heavier than your target mineral, the system will then be set up to discharge your target mineral along with tailings.

What you should do with the heavy materials from the bottom of a jig depends entirely upon what they contain.

On the production dredges we build at Pro-Mack, it is common to have a series of three jigs. The first (called a “rougher”) accepts the classified raw material from the sump under the dredge’s screen. The rougher accepts a larger classification of material at volume speed. Its purpose is just to make an initial classification and trap the largest gemstones and heavy metals on top of a bed (smaller classification screen) inside the jig. Large materials and the lightest small materials flow off the top of the rougher-jig as tailings. Heavier, classified materials are bled off the bottom and directed into a “secondary-jig.”

The secondary-jig can be more finely-tuned to further separate a finer-classified, slightly-heavier material at a slower speed. Then the finer-classified, heavier material from the bottom of the secondary jig is fed into a “finishing-jig” – which can be tuned to complete a final separation.

The following video sequence demonstrates how these systems harmonize together:

Most or all of the gemstones will become trapped on top of the jig-beds (classification screens) inside of the jigs. If there are fine-sized heavy metals present, the bleed from the bottom of the finishing-jig usually is directed into a final concentrating device – commonly a centrifugal bowl. The final concentrate is then separated in camp, often with the use of a mechanical shaker table. This final step is demonstrated by a video segment included in an article that I wrote about a sampling project we performed in Cambodia.

As all of these mechanical recovery systems are very sensitive to sudden jerking movements, changes in water pressure and other factors, we have found that it is much better to set up the recovery system for a production dredging operation on its own independent flotation platform. This includes the water pumping system that supports the recovery system(s). Here are a few reasons why we have found this works better:

1) Dredge platforms jerk around a lot as the suction nozzle is managed underwater. The suction hose is flexible, so there is an accordion-affect when varying amounts of suction are used at the nozzle. This causes the dredge to bounce around. The bouncing can throw off critical settings on mechanical recovery equipment.

2) Demands made upon the dredge’s main water pump fluctuate widely, depending upon how much suction is being used at the nozzle. If the dredge’s water pump is being used to supply water to mechanical recovery systems, the pressure-fluctuations can throw off the criticle suspended mediums that make the systems work.

3) A production gold dredging platform has a constant parade of divers, managers and tenders moving about while doing their various jobs. Most recovery systems are designed to be fastened down to a level, stable platform. The movement of numerous people around a dredge platform can throw off important settings.

4) Security: The final product(s) on a commercial mining operation should accumulate in a safe location where traffic can be carefully controlled.

5) These mechanical recovery systems have a lot of moving parts. It is better to keep wet, slippery divers and all their gear clear of the machinery.

In my view, the best way to do it is to set up two platforms:
A) A dredge platform that you can move around, put divers and tenders on, pump raw material to; and pump classified materials from.

B) A recovery platform that receives the classified materials and processes them. This system needs to be carefully engineered, and large enough to manage the volume of raw, classified material that is directed to it from the dredge. You only need to have one or two operators on this platform, so as to not upset the delicate balances that can be easily offset by people walking around changing the way the platform is sitting in the water.

Please take a closer look at the point I am trying to make here by viewing the following video sequence. See how much more organized it is to have a separate platform to contain an advanced recovery system. Just picture trying to combine all of that equipment onto a single platform and still retain some mobile flexibility:

I have found that when you try and put it all on one platform, you are forced to ignore several vital factors which can ultimately add up to a dredge-package that does not do the job very well.

 

 
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By Dave McCracken

Under many circumstances, it is wise to first verify that a viable deposit exists on a property before a substantial investment is made into production equipment.

Dave Mack

 

How to outfit a suction dredging project, to a large degree, comes back to how you would answer the following questions:

1) What am I trying to accomplish; (sampling, production, or both)?

2) Where?

3) In what period of time?

4) How much of a budget is available for acquisition of equipment and for operational start-up costs?

A gold (and/or gemstone) mining project basically should to be looked at in two separate steps: First you sample to locate a viable deposit. Then you launch into a production program to recover the gold or other valuable minerals from the deposit. Generally, the idea is to minimize investment into a particular mining property until a viable deposit has been located and verified.

Production-equipment is commonly larger and is more expensive to purchase and move around. The logistical infrastructure to support a production operation is usually more substantial and costly than what would normally be required to just go in somewhere for a short sampling program. . So generally-speaking, a production operation costs more to set up and involves more gear and supplies to move around and put into place. Therefore, under many circumstances, it is wise to first verify that a viable deposit exists on a property before a substantial investment is made into production equipment. The idea behind sampling is to minimize risk.

Prospecting Equipment & Supplies

The following video sequence will provide you with a visual demonstration of this very important point:

A typical camp to support a preliminary sampling operation usually would involve just the basic necessities.

The answers to “Where?” and “For how long?” also impact upon your decision about what kind of gear to buy. For example, if you are not tied to just one mining property, and you are prepared to launch a sampling program onto different properties until you find what you are looking for, then it would be a good idea to invest in good sampling equipment that is portable enough to move around the properties which are available to you. In this case, the capital expenditure is not tied to a single property, but rather into a portable sampling infrastructure that can be used for an extended period of time in many different places.

While sampling-gear is more portable, the smaller the size of a dredge, the less volume of streambed material it will process (in the same experienced hands), and the less-deep it will effectively excavate a sample into the streambed. Therefore, you trade-off productive effectiveness and the capability to make meaningful, deeper samples as you reduce dredge-size and gain in portability.

Two Pro-Mack 5-inch dredges were used to find rich deposits on this river in Cambodia, before a 10-inch production dredge was brought on line.

As an example of this, a 4-inch dredge can effectively sample down to around 4-feet deep in hard-packed streambed material). A 5-inch dredge can excavate about twice the volume of a 4-inch dredge down to around 5-feet of material. But the bulk of gear to move around is about twice as much.

A 6-inch dredge can excavate about twice the volume of a 5-inch dredge down to around 6-feet of hard-packed streambed. But the bulk of gear to move around is about twice as much.

An 8-inch dredge can excavate about twice the volume of a 6-inch dredge down to around 8-feet of material. But the bulk of gear to move around is about twice as much.

Here follows a video segment of a typical commercial dredge operating on the Klamath River in Northern California:

Ten-inch Pro-Mack dredge operating on New 49’er properties in Northern California.

A 10-inch dredge can excavate about twice the volume of an 8-inch dredge down to around 10-feet of material. But the bulk of gear to move around is about twice as much. By now, we are talking about a pretty substantial platform. But it still remains portable enough to place inside of an ocean shipping container, and can be towed around on wheels behind a small truck. For example, watch how this recovery platform for a 10-inch production dredge can be moved around by a normal-sized truck. This particular platform was built to ship overseas inside of an ocean shipping container:

These are just guidelines, because conditions change from one location to the next. It does not mean you cannot dredge deeper into the streambed using smaller-sized dredges. You can! But it generally does mean that the deeper you go beyond these guidelines, the less effectively your time will be invested. This is mostly a matter of over-sized rock management. All rocks that are larger than the intake-size of the dredge’s suction nozzle must be moved out of the way by hand. When dredging in an average hard-packed streambed, at the point where an experienced operator gets down through 5-feet of material using a 5-inch dredge, he has so many rocks to get out of the dredge hole that he is lucky to spend half his dredging-time operating the suction nozzle!

Bigger dredges get more accomplished primarily because they will suck up larger-sized rocks.

Under most circumstances, there are a proportionate greater number of smaller-sized rocks in a hard-packed streambed, than larger-sized rocks. So this is really a discussion about effective time-management. Since a larger dredge will suck up a larger rock, it means the operator will not have to move smaller-sized rocks from the excavation by hand. So he or she will spend his time moving even larger rocks out of his way, of which there are proportionally-fewer. This means he will get more done faster, and be able to dredge deeper into the material, before he reaches the point that there are just too many rocks to move out of the way.

Using a 5-inch dredge will mean having to move many, many more rocks by hand that would more-easily be sucked up the nozzle of a larger dredge.

This important reality cannot be overcome by positive thinking or an abundance of enthusiasm (as important as these are to have). We are talking here about the physical reality of how an excavation is accomplished. The size of the dredge-nozzle determines what size of rock can be sucked up (which is fast and easy), and what must be moved out of the hole by hand (which takes more time and effort).

The following video sequence demonstrates this very important point, and also explains why you must be very careful about projecting the true volume capability of different-sized dredges during feasibility planning:

By the way, when conditions allow for it and you want to increase the productive capacity of your equipment, you can also organize two or three separate teams to take shifts using the same production equipment. As demonstrated in the following video sequence, lights can even be set up to do a night shift:

So when deciding what to acquire for sampling or production equipment, it is necessary to balance the desire to get more productive activity accomplished (bigger dredge), with the necessity to remain portable (not so big that you cannot move it around to find what you are looking for). This must be decided on a case-by-case basis.

Here is my advice: Go as big as you are able to without forfeiting the portability that is required for your particular situation. I suggest these important decisions can only be wisely made after at least a preliminary evaluation of the project-area is completed.

Once you have proven-out your deposit(s) by sampling, you can feel more comfortable investing in production equipment and support-infrastructure to develop the project. In that case, bigger is not always better. Sometimes it is. A lot will depend upon the depth of water and streambed where you will be dredging. For example, a 10-inch dredge might not be as productive as a 6-inch dredge in a shallow-water and shallow-streambed area where a larger dredge cannot be floated around easily.

Another example is where shallow streambed material is made up largely of boulders that must be winched out of the way. In this case, some of your money might be better invested into a good mechanical or hydraulic winch, rather than a larger-sized dredge.

A well-done preliminary sampling program should result in a good production plan, based upon what type of equipment will be required to obtain optimum production under the conditions which exist where the gold deposit is located.

I am not going to discuss sampling, production or recovery systems here, because they have been covered in other articles. But since the type of equipment you should acquire is directly related to these subjects, I suggest it is a good idea to review that material very closely.

Some dredges are made to operate from the surface with the use of an automated cutter-head device at the nozzle. These are generally ineffective in hard-packed streambeds that are mostly made up of oversized rocks.

Some dredges are available with hydraulic-powered cutter-heads to help with the excavation. These are mechanical devices that help feed material evenly into the nozzle. They are most productive in doing channel-work in harbors or making navigation channels deeper or wider. Hard-packed streambeds which are made up mainly of oversized rocks and boulders will usually destroy a cutter-head device in short order.

Here follows the normal steps in the development of a mining program:

1) Preliminary evaluation: This is where you take a hard look at the available information about a potential project. Then you go out and have a direct look at the specific location(s) and surrounding area. You are looking at the potential for commercial gold (and/or gemstone) deposits. You are also looking at what it would take to accomplish a preliminary sampling program, based upon all of the information and observation you can bring together. A preliminary evaluation will often result in a preliminary sampling plan.

2) Sampling Program: Depending upon what the objectives are, sometimes sampling is accomplished in several stages. Generally, the purpose of a sampling program is to locate and verify the existence of a commercial deposit that is valuable enough to justify a production operation. Sampling should work out the recovery method upon which the deposit may be developed efficiently. A sampling program can evolve into feasibility planning to develop a mineral deposit.


3) Production Operation: Is full or partial development of the deposit.

While there can be some overlap, equipment needs are usually different in each phase of a mining program.

While each project is different, during a preliminary evaluation, I personally always at least bring along a face mask (so I can have a look at the underwater environment where we would sample), a gold pan and classification screen, zip-lock sample bags and marker pen, map, GPS, camera equipment, local money in small denominations (to buy mineral samples from local miners), a dozen bright-colored ball-caps (gifts for local miners), a bottle or two of whiskey (gift for the village chief in non-Muslim communities), and the other basic things I will need to visit that particular environment.

A sampling program will basically require the same things as will be required in a full production operation, but usually on a smaller and more portable scale. Here follows a basic outfitting list:

Dredging Equipment:
Dredge
Boat (and motor?) and ores
Winching gear and rigging?
Pry-bars
Rope (floating)
Fuel containers
Complete set of tools needed to service the gear

Diving Equipment:
Face mask
Air reserve tank and fittings
Air line(s) & regulator(s)
Wet-suit?
Weight belt & weights
Protective foot ware (steel tips?)
Rubber work gloves (bring spares?)

Clean-up Gear:
Wash tubs
Classification screens
5-gallon buckets
Scraping tool and/or hand scoop
Final concentrating equipment?
Gold pans
Steel finishing pans
Magnet
Portable gas stove
Weight scale
Zip-lock sample bags and marker pen

Support Gear:
Vehicle-support?
Shelter
Cooking & eating utensils
Wash tub for kitchen
Cook stove
Toilet facilities?
Portable chairs & table
Medical kit
Waterproof bag(s)
Ear infection preventative
Maps, GPS and camera equipment
Electric generator?
Camp lights
Paper and pens
Communication equipment?
Flashlights & batteries
Knife
Firearm?

Supplies:
Drinking water and/or filters
Food supplies and containers
Fuel & motor-oil for all motors
Dish washing detergent
Chlorine for sanitizing cleaning water
Laundry wash tub and soap
Hand-wash soap
Tissue paper
Cook stove fuel or canisters
Duct tape
Nylon line (plenty)
Plastic trash bags
Zip-lock bags & plastic containers for food

Spare Parts (priority often depends upon how remote the project location is):
Tune-up replacement parts for all motors
Extra water pump seals and bearings
Extra compressor & alternator belts
Rebuild kit for air compressor
Extra air compressor?
Rebuild kits for dive regulators
Extra dive regulators?
Repair kits for diver air lines
Extra diver air lines?
Extra air fittings
Extra water pressure and intake hoses
Extra water hose fittings
Extra rubber hose seals (each size)
Extra foot valve(intake for water pumps)
Extra suction hose?
Extra face mask(s)
Extra starter & alternator & fuel pump for dredge motor?
Spare tire (if dredge has removable wheels)

 

 
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By Dave McCracken

“Planning to Get it Right the First Time”

Dave Mack

Planning for a mining program largely involves the following elements:

1) Legal
2) Location and accessibility of the project site
3) Politics with government and local people
4) Timing
5) Operational considerations
6) Shelter and living-support
7) Specialized equipment
8) Supply of food, fuel, supplies and other needs
9) Security
10) Medical and/or emergency support
11) Communications
12) Personnel

All of these elements are vitally important and each must be managed well to make a mining program successful. I’ll just briefly discuss each element in general terms.


Sometimes, it is necessary to construct your own road into a remote location.

Because every project is different, relative levels of importance will change depending upon local circumstances. To give you some idea about this, I encourage you to read several articles about the challenges we have faced on different types of projects from our own past experience. Reading through the stories will give you insight into why good planning in advance vastly increases the potential for success in any project:

Legal

The serious part begins with acquisition of the legal right to pursue a mining project. While this is always important, the need to protect your own interest increases in proportion to the magnitude of your investment. It also increases in proportion to the potential for valuable success. My best advice would be to make sure your legal rights are secure during the very early part of the development-stages in your mining program.


Because gaining the legal rights to a mineral property can sometimes require substantial investment in itself, it is not uncommon to perform the preliminary evaluation, or even a preliminary sampling operation, before negotiation of legal rights are finalized. In this case, it can be wise to negotiate the final terms in advance, pending the outcome of your preliminary evaluation or sampling.

In other words, you might not want to buy or lease a mineral property until you are certain for yourself that a commercial opportunity exists for you there. And you also probably will not want to invest the resources to prove-out a deposit unless you are certain you can develop a project if something valuable is found. Balancing these two needs is a challenge that must be overcome.

Note of caution: In the event that you will invest your own resources into some preliminary field-work to evaluate a property before final negotiations are completed, some consideration should be given to keeping the results of your initial observation and results confidential. This is so that the information does not undermine your position in the negotiation. While this is not always appropriate (depends upon your agreement with the property-owner), it is definitely something that should be considered during planning.

The bottom line is that you will want to make sure that your investment into a project is going to be secured by legal agreements in advance.

In some countries, dealing with the officials can be the biggest challenge to your project manager.

Another note of caution: One has to be particularly careful when negotiating agreements with private parties and/or government officials in developing countries. Sometimes corruption will undermine the rule-of-law. Under these circumstances, legal agreements may not be enforceable. The U.S. State Department usually publishes a brief risk-assessment about doing business in most countries.

In any event, if you decide to proceed, it is wise to secure the services of competent legal professionals residing in the country where you will do business.

Location and Accessibility


The location of your potential project site(s) will substantially affect the cost and difficulty of pursuing a mining program. Equipment, fuel, supplies and personnel must be transported to the site, and withdrawn when the project is complete. This will need to be accomplished either over land (using roads or trails), by water (using boats) or by air (using airplanes or helicopters).

“Remoteness,” these days, often has more to do with the cost of transport, than the distance things need to be moved. For example, a project site that is accessible by a 2-day river trip on a sizable transport-boat can be much-more easily accessible, than a site that is much closer to civilization, but requires everything to be transported via a 45-minute helicopter ride.

  

As every situation is different, important consideration and cost-analysis must be given to how you will move gear, supplies and people to and from your project site.

The more remote the location, the higher-grade the mineral deposits will need to be to justify a mining project.

Politics with Officials and Local People

Any mining program will find itself interacting with government officials and people who reside in the area where the activity will take place. The politics involved with these various relationships is important to maintain, and always will depend, in large part, upon good judgment and emotional flexibility by the project manager. This is even more true when local people will be hired to help support the mining project.

Environmental considerations fall into this element. Not just the true environmental consequences; but just as importantly, the perceived potential impacts that local people, various NGO’s and government officials worry about — even if their perceptions are not based upon reality. You have to manage the real environmental considerations, and you also have to respond to the way people are reacting to your mining program.

Managing relationships with officials in developing countries is a very challenging and risky business.

Because each situation is entirely different, no matter where you do your mining, the best advice I can give concerning this important element is to make sure you have a level-headed project manager that has some vision and understands that every action will have a consequence.

 

Timing

It takes very specialized people to recover good samples off the bottom of a muddy river.

Effective dredging operations require underwater visibility. Visibility is necessary to execute a planned excavation of a dredge-hole, and also for more than one diver to work underwater in the same excavation.

Muddy water turns visibility to pitch black just inches below the surface. Submersible lights do not help, because they will not penetrate through suspended sediments. So a dredger’s progress in dirty water is reduced to whatever he can or she do by feel. It is a very slow process, and safety-margin for the diver is radically-reduced.

Many mineral-rich areas on the planet have distinct wet and dry seasons. It is important to look into this. Because waterways most-often flow at higher, faster levels during the wet periods – and can also run with poor or no underwater visibility.

More often then not, Rainy seasons create conditions that prevent dredging operations from being effective. It is very wise to plan your sampling and production programs to begin at the beginning of the dry season.

  

Besides making dredging conditions nearly impossible, the rainy season can also turn road-access into a nightmare! As an example of this, check out the following video sequence that I captured on a road in Cambodia during the rainy season:

When operating in developing countries, unanticipated delays can often delay start-up times by weeks or months. So it is better to time such programs to have all the legal matters resolved, important relationships in good order, and equipment ready to go well in advance of the dry season. While this may sound obvious, more often than not, our Pro-Mack Team has been called in to help with dredging programs just as the rains were beginning and the river was turning muddy. The water was so dirty in the following video sequence, that it was pitch dark only inches below the surface:

Starting a dredge-sampling or production program during the rainy season is near to creating a mission-impossible scenario for the project manager. And your divers, no-matter how enthusiastic they are in the beginning, are likely to lose some of thier motivation to continue once they experience the nightmare of a dark and mucky river-bottom..

Still, sometimes you are forced to do preliminary sampling when conditions are not ideal. In this case, it is important to make safety the primary concern and also realize that results will only be a fraction of what can be accomplished under more suitable conditions.

Project operational considerations

This is all about how you are going to do the sampling or production-part of the program. This is the mission-plan. What are you going to do? Where? For how long? Exactly how are you going to accomplish it? Who is going to participate? With the use of what gear and supplies?

Are you going to need a boat to move your equipment, fuel and people around on the river, or are you going to use roads or trails? Will your access to different places along the river be challenged by extreme fast-water areas, or water that is too shallow to float the dredge?

Are you going to set up a single base camp and return there at the end of each day? Or are you going to move the camp as you make progress sampling along the river?

How deep is the water and streambed material? This will affect the type and size of dredge you will need to accomplish the job, how much dredge-power you will need, and how long the suction hose and air lines need to be.

Will you be dredging in fast water areas? This might require you to bring longer hoses to extend your reach while keeping the dredge tucked into slower-water pockets along the edge of the river.

Are there any critters in the water, or along the edge, that you have to defend against? What special gear is needed for this?

In some places, equipment to move big rocks is even more important than the dredge you will use. Are their big boulders that will require special winching gear to move?

Will you need to bring along special tools to cut a trail or to build living platforms in the jungle?

How are you going to recover the gold (or gemstones)? This is a big question that should be resolved as well as possible during the preliminary evaluation, and entirely confirmed during sampling. If a specialized recovery system or process is required, you will need to bring the gear and supplies along with you so you can perform those tasks.

Shelter and living-support

How you will feed and shelter the people who are part of your project largely depends upon the nature of the people involved, how dangerous or uncomfortable the environment is, and how long they will be there.

  

Generally, you will find that helpers from the local village have their own way of providing shelter for themselves and the food that they eat along the river. Sometimes, they don’t require much more from you than a plastic tarp and some rice. I have been in a lot of jungle environments where the local help either brought along their own hammocks and a cooking pot, or already had small shelters set up along for themselves the river.

It is important to address the needs of the local help (which are usually not much) during the preliminary evaluation, and not impose conditions (or food) upon them that they are not comfortable with.

Bringing specialists into a harsh environment from the comforts of civilization requires careful planning. While this may not be true everywhere, it is my own experience that while local helpers are somewhat amused by the special requirements of westerners, they usually do understand that we are not jungle-dwellers like they are. However else they may feel, there is always respect (and desire) for the nice toys and tools that we bring along.

Sometimes, the most important part of shelter is to get off the ground.

The bottom line is that you must bring along whatever is necessary to shelter your personnel from the dangers and any severe discomforts of the environment. Every place is different. A tent goes a long way to keep bugs and (smaller) critters separated from people. Sometimes (often) it is necessary to set up camp off the ground, even when tents are being used. This may require bringing along some wooden boards to put up a platform. Sometimes the platforms already exist, made out of lumber, bamboo or small trees. Sometimes they can be constructed from materials that are present on site. For example, the following video sequence shows a preliminary base camp where tent platforms were constructed from hardwood lumber sawed out of trees on site (with a chain saw):

The locals will know what you need to do to keep your personnel safe from the more serious threats. You will have to use your own judgment how to provide people with support that will keep them reasonably comfortable under the circumstances. It is important to figure this out during the preliminary evaluation.

On many of the projects that I have been involved with, we hired several helpers from the local village that were also good at hunting and fishing. This reduced the amount of food that we needed to bring along.

A word of caution: When hunters bring dogs, it is wise to avoid making very much contact with them. These jungle dogs are loaded with critters that would much-prefer a human host! Hunting dogs generally increase the need to reside off the ground.

Another word of caution: When living with jungle-dwellers, you must be especially vigilant at imposing strict sanitary measures with anything to do with the food and water that you will consume. This is not easy; because your jungle helpers will not understand, and it is near-impossible to overcome normal routines that are part of their life and culture.

There is a lot to be said about bringing along a special cook who will look after the food and water-needs for the personnel on the team that come from non-jungle environments. This must be a person who already understands basic sanitary principles; and ideally, who normally resides within an environment where such measures are practiced. We have found from past experience that it is too late to try and teach sanitary measures to someone (who will prepare your food) after you arrive in the jungle. And since you cannot watch everything that is done to prepare your food, you can find yourself with a whole crew of sick (sometimes seriously) people even before you hardly get started!

The bottom line is that you have to plan on providing food and water that will not make your people sick, and it is important to provide them with a reasonably comfortable, safe environment to sleep at night.

Specialized equipment

As we have discussed equipment needs in other articles, I will not go into them here. The main point is that you must bring along the gear that will allow you to accomplish the mission.

When accurate samples are required where special recovery equipment is needed, and the sampling must be accomplished with portable dredging equipment, it is sometimes necessary to dredge the samples into special, floating catch-containers. Then the samples can be carefully processed on land.

Here is where you can buy Gold Prospecting Equipment & Supplies.

 

Supply of food, fuel, and other needs

It is important during the preliminary evaluation to establish where you will acquire fuel, food and other supplies to support your program. There are many primitive areas in the world that do not have structures, services and supplies like we do in the west, so you cannot just assume operational needs will be readily available. For example, the following video segments show areas where we have had to supply mining projects where even small corner food markets are not present, much less Safeway or Albertsons:

Sometimes, access is such that you can plan for a continuing supply of essentials and other needs as the program moves forward. Sometimes, difficult access requires that you bring everything in at the beginning, or plan on occasional deliveries. To keep costs down, deliveries must often be arranged by local boat traffic or by cart over primitive trails. The following video sequence was captured on a project we did in Madagascar, where local deliveries were made by ox cart:

Occasional or regular deliveries increase the need for dependable communications and financial arrangements so that you can better-coordinate with those who will provide the support from a distance.

As there is no refrigeration in the jungle, it is usually true that hunters will need to come up with something every day to keep meat or fish on the table. Even if local help will provide a local supply of protein, we have found that it is a good idea to bring in a supply of freeze-dried meals or canned goods – just in case the hunters have a dad day. Being hungry is hard on morale!

Security

Security is always a concern on a mining operation, on multiple levels. There is the gear out on the river, the gear and supplies at the base camp, the personnel involved with the operation, and the product that is being accumulated. Understandably, every situation is different; so flexibility and good judgment is required.

Under a lot of circumstances, many security concerns can be resolved by investing some advanced-effort and goodwill into the politics with the village(s) in the surrounding area, and with the local people that are hired to help you. A good manager will strive to find the balance between helping a little with the needs of local people, with getting the job accomplished that he is there to do within the budget he has to work with.

One of the first key people to hire in a mining program is a good interpreter. This must be a person whose politics are not in conflict with the local villages. It is important that you enquire about this, because sometimes there are politics going on that you cannot see on the surface.

One of the first priorities during a preliminary evaluation is to pay a respectful visit to the village chief or elder(s). Bringing along a bottle or two of whiskey to present as a gift (unless it is a Muslim community) is almost always a great inroad, and eliminates the requirement that you drink the local brew (which can make you sick) when making friends.

I always make a strong effort to bond with the leaders of the local village(s). For the most part, it is accurate to predict that politics with the local people will go just about as well as you have made friends with the local leaders. Here is a place where a little time can be invested well.

When visiting with local leaders during the preliminary evaluation, I look around to see what I might bring as meaningful gifts that can be shipped over with the sampling gear if we decide to take things to the next level. I am not talking about spending a lot of money on gifts. Flowers don’t cost very much, but look how much they are appreciated when you present them in a meaningful relationship! Thoughtful gestures go a long way in a new relationship, especially when there is a wide gap between the cultures and the toys being played with.

Being thoughtful in advance can be far less costly than the loss of key gear or equipment by theft, once you are committed to a sampling program.

Some mountain-river environments have very limited access, and not very many people or traffic are moving around. These communities can be rather small, and there are not many secrets. If the general consensus amongst the local people is to support you and/or leave you alone, you will usually not have very many problems with security.

Sometimes you have to resign yourself that there will be a continuous audience of onlookers watching the mining activity along the river. This is mostly because local people have never seen anything like that before. So it may be necessary to work out some reasonable boundaries with the village elders.

  

Whenever possible, we set up camp some distance away from the local village. This is good practice for a number of reasons. But mainly, it sets up a natural boundary (by distance), creating some degree of privacy. I have never been on a project where local villagers did not respect the privacy we created by setting up our camp some distance away.

I have also found that bringing along some small gifts (like extra pocket knives or Leatherman tools) goes a very long way with the most productive helpers. Although, I keep those out of site, and only pass them out after I have managed some initial bonding with some of the helpers. Special rewards to the most enthusiastic supporters can help build productive relationships.

Generally, we have found that if you treat them with respect and kindness, helpers from the local village understand that we are not the same, have special needs that are different from theirs, and possess desirable belongings from another world – which belong to us. If something turns up missing, I usually make an issue of it right away. This can cause the item to turn back up a little later and eliminate future problems in this respect.

Places where your personnel are in danger from other human beings will require site-specific security measures. Some mineral-rich areas have ongoing civil wars, separatist groups or insurgencies to worry about. Some places have people or groups that kidnap outsiders and hold them for ransom as a means of supporting themselves and their political movements. Needless to say, these are concerns that are important to discover during the preliminary evaluation. Such concerns will almost always be outlined within the State Department’s information about the country. The following video segment was taken in Cambodia on a project where it was necessary to maintain our own local security force:

Increased security problems raise the level of cost. Therefore, the mineral deposits must be richer to justify the risk.

Some careful thought needs to be given to how you will secure money, gold or gemstones, sample results and the other valuable possessions during a mining project. This should probably involve a security safe during an extended production program.

During a sampling program, it just might be that the project manager needs to keep the valuables in his personal possession. Waterproof bags are good to have along for this.

A word of caution about this: If you are making payments to others in the field during a project, it is unwise to pay directly from the source of where you are keeping the valuables. For example, opening up the day-pack where you are keeping all the valuables to pay a vender in the village. Because secrecy is the only security you have protecting those valuables, it is better that outsiders do not see where they are being kept. Keep the bigger money-stash a secret from anyone who does not need to know. In a private place, pull out enough to pay for things, holding that money in a pocket, wallet, belt-pack, or whatever.

This secrecy-concept also extends to the gold you recover on a mining program. Especially during production! We always set up the final processing structure well away from local traffic, and only allow those near that should or must be involved. The product is never shown or advertised around. It is also hidden like the money, if there is not a well-anchored security safe where it can be locked up.

Showing large amounts of money or other valuables (relative to local levels of income and wealth) is a sure-way to increase security-risk on any mining or sampling operation.

As long as we are on this subject, you also should be careful with your valuables in hotel rooms within developing countries. Keep valuables out of sight, locked up in a suitcase, on your person – or sometimes the hotel provides a safety deposit box. You have to use your own judgment what is the best way to keep things safe. It can be a big mistake to assume the hotel staff, or even the manager, will not go through your room and belongings when you are not present!

 

Medical and/or emergency support

When setting up a mining program, it is important to establish how and where your personnel are going to receive medical care if they need it, and also emergency support if there is any kind of serious problem.

A lot depends upon how inaccessible the project site is. When there are villages nearby, you can sometimes find some local medical assistance for matters that are not of a serious nature.
The villages sometimes will have a method worked out to manage medical emergencies.

Sometimes you can locate an emergency-evacuation service from a larger town or city that will send a helicopter or small plane to recover someone who needs emergency medical care. It is a good idea to arrange this service in advance, and work out how you will communicate with them in the event that you need their help (at any hour). It is a good idea to arrange a medical-evacuation service, even if there are local medical services available. This is because medical care generally is better as you get to larger hospitals that provide service to bigger populations

   

There is also international emergency medical evacuation insurance available at relatively low cost. This service will send a medical team out to recover you in a medical emergency anywhere in the world when competent medical assistance is not available where you are located. We always require any and all personnel who accompany me on a project outside of America to obtain this type of insurance.

While there are probably many other options for this type of insurance, I have personally had good luck with Travelex Insurance Services (800 228-9792). They provide $50,000 in world-wide medical evacuation/repatriation insurance, plus other benefits, at a cost of around $260 per year. And I happen to know that they make good on it. One of my guys was critically injured in an automobile accident during a project in Madagascar several years ago. Local medical care was poor. So the insurance company immediately arranged to send an airplane with a medical team on board. They evacuated my guy to La Reunion Island (France), where they proceeded to save his life. As soon as he was safe to move again, they repatriated my friend to a hospital in San Francisco. He survived only because of this insurance.

The type of work, and the environment where we perform it, is already dangerous enough. Preventative measures are the best way to avoid medical emergencies. The more remote the location, the more careful everyone has to be.

During preparation for a project, one of the first things we do is have all my helpers go into the local county health department (America) and bring themselves up to date on every inoculation that makes good sense for the location where we will do the project. Because we work in the water, it is important that my guys are up to date on their hepatitis, typhoid and tetanus shots. In addition, county health departments have written guidelines (put out by the World Health Organization) for all areas of the world, listing other concerns (and preventatives) for specific areas.

The three primary ways to get into a medical situation during a project are:

A) Accidents: While accidents do happen, they mostly can be avoided by planning things out well in advance and having responsible people involved who are being careful. Good management and responsible people can generally stay a few steps ahead of Murphy’s Law (Anything that can go wrong, will go wrong, at the worst possible time!).

 

No matter how good they are at what they do, we never include “wild and crazy guys” in projects where I am asked to participate or provide a team. The risks to the project are too high.

B) Critters: The local people will know what they are and how to deal with them. It is important to find out what the threats are, especially within the water-environment where we work.

Because we dredge in the water during the sampling phase, it is vital to find out what the critter-problems are (if any) during the preliminary evaluation.

When I first visit a potential project site, one of the most important things I look for is to see if local villagers are bathing, doing laundry and swimming in the river (especially the children). It is always a good sign if they are. Life revolves around the water along these river-communities. So if you do not see people in the water, it is important to find out why.

There are plenty of things to worry about in the water – like snakes, flesh-eating fish, flesh-eating reptiles, electric eels, different types of aggressive mammals, and smaller critters that make you sick in different ways. The local villagers will know about them all (if any). They will also know how to avoid danger. When talking to the locals about the potential dangers to divers in the water, I cannot over-stress the importance of having along a really good interpreter – who will take his time and do his absolute-best to establish some dialog and understanding on this important subject.

If there are local villages within the vicinity of where we will do a project, during the preliminary evaluation, I try and visit each and every one of them. Besides the other things that I do during these visits, I also try and find out if there are sick people in the village – and what they are sick from. In addition to gaining an idea if the sickness might be something that could impact upon our project, it also creates an opportunity to return with medical supplies to help the village if and when we follow up with a sampling program. Helping the sick people in a village is a sure-way to make friends.

C) Sanitation: During my visit to the local villages, I also look to see what they are doing for toilet facilities. If they are going right out into the river, we will need to bring along our special full-face dive helmets to reduce exposure to dangerous bacteria.

Often, the primary sanitation-concern is inside your own base camp. Not to get too graphic about this; but it is common practice all throughout the developing world (especially in the remote areas) for people to wipe themselves with their hand, not wash well (if at all), and then go directly into food-preparation. Locals normally can drink water (with apparent impunity) from the river (or a well having ground water exposed to unsanitary conditions from the village); water that would put an outsider into a good hospital for a week (and there probably won’t be a good hospital around under those circumstances)! They use that water for drinking and cooking. Because these are practices everyone does in their community, and they are part of their everyday world, it is nearly impossible to have locals do food preparation for you without substantial risk to your personnel.

The best way to avoid continuous problems with sanitation (can be very serious), is to set up your own camp some distance away from local communities and bring in your own cook. This can be someone from the same country who lives in an environment where sanitary-measures are a normal way of life. Then, your cook must insist that he or she is the only person that comes in contact with the food that you will eat and the water you will drink (and that will be used for cooking). This can be a little tricky when there are hunters or fishermen involved, but it can be worked out.

When initially setting up a base camp, it is important for the project manager to walk through and review all the vital elements that will affect sanitation. How and where are the toilet facilities set up? Does everyone know where to go? Is there tissue paper — and will people actually use it? Is there a place to wash up (with soap)? Where is the drinking water coming from and being stored? Is that being kept well-separated from unsanitary water? Do all your personnel know where to find the good water? How about the cooking water? Where are the cooking and eating-utensils being cleaned up and then stored? Who is cleaning game animals, how and where?

We also always bring a medical kit along. Besides the standard items included in an emergency medical kit, here is a list of items that we also include:

Aspirin
Anti-Rash powder/spray
Domeboro-ear preventative
Ear antibiotics
Eye wash
Hydrogen peroxide
Antibiotic ointment
Pain pills
Internal antibiotics for wounds
Antibiotics for respiratory-infection
Diarrhea antibiotics
Lip balm
Salt tablets
Thermometer
Malaria medicine
Alka Seltzer
Tums (anti acid)

While all of these items can be purchased over the counter in many places outside of America, it is wise in today’s world to obtain a doctor’s written prescription for any items that would require it during international travel.

 

Communications

Several levels of communication are necessary in a mining operation. Communication is usually necessary between project personnel and local helpers, between the different personnel involved with the project, and between the project and the outside world.

For communication with locals, I cannot overstress the importance of finding someone who knows each of the languages very well, who is honest, helpful and genuinely interested in your project. This is just as true when dealing with government officials.

An enthusiastic interpreter will dig for the information that you want to obtain. When communicating with local people on the river, sometimes it is necessary to ask many questions in different ways, to different people, to bring them around to the same concepts that you are trying to express. When you work with people from different cultures who have radically-different backgrounds, often you find that they just do not conceptualize things the same way that you do. A good interpreter is able to bridge this gap and help you get the information you want with some degree of accuracy. He will also help you avoid misconceptions or misunderstandings that can build up stress with locals along the river.

There are plenty of low-cost weatherproof walky-talkies available today which can be very helpful in a field environment where personnel are separated by relative short distances – like between the base camp and where some mining or sampling is being done along the river.

Longer-range radios are often used between the base camp and civilization. Although atmospheric conditions sometimes make this mode of communication unreliable.

Satellite phones keep getting more portable and easier to use as time moves forward.

The cost of satellite telephone systems has come down dramatically during the past few years, and is probably the best solution for a remote base camp’s link to the outside world. Many satellite systems will allow a laptop computer to be connected for data-transfer. This is particularly useful for sending progress reports and images. It is also useful for sending supply lists to whoever is supporting the operation. A satellite telephone is very valuable in dealing with emergencies!

Personnel

I saved this section for last, because it is really the most important. If you study all of the material on this web site, you should realize over and over again that it is the personnel on your project that determine the final outcome. They are the key factor that makes it all happen.

Mining projects are not easy. There are many challenges to overcome. Every decision made by the manager and others involved with your project will move the world in a direction that either contributes or subtracts from the momentum necessary to reach key objectives. Ultimately, the people you choose to play in your band will determine exactly how the music sounds. I have discussed this very important element in other articles:

There are so many details that must be put in their proper place and managed correctly to accomplish a successful sampling program, or a production mining operation, that there is little chance of ultimate success unless the program is managed and implemented by experienced, responsible, enthusiastic people that are strongly motivated to make it all come out the right way.

 

 

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.

 
Dave Mack

“For all your prospecting equipment & supply needs!”

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Located alongside New 49’er headquarters at
27 Davis Road in Happy Camp, California 96039

Please ask for Montine at:

Phone: (530) 493-2062
Fax: (530) 493-2095
Email: montine49ers@goldgold.com

  
 
Dave Mack

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Dave Mack

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by George McConnell

What can go wrong will!! And does!!

Never has such an adage been more true than with small engines – on a prospecting trip – a BILLION miles from nowhere! The engine sits after your arm breaks from trying to start it, and tempers flare while someone screams “The thing worked last year!”

Here are a few tips:

Repair of anything in the field is much more difficult, not to mention the trips to town for a spark plug wrench, or a clamp, only to find the store just closed! Make up a small kit of tools and parts to keep with the mining equipment.

1. Pliers
2. 4-way screwdriver
3. Inexpensive socket set with spark plug socket that will fit your spark plug!
4. Allen wrenches
5. Extra engine oil
6. Extra pump seal kit and gaskets and clamps
7. Extra spark plug
8. Whatever else you can think of that you’ll need!

Ok-ok, the season is over and I’m dreaming of next year’s expedition. DON’T WAIT. Now is the time to pickle that engine!

How to “Pickle”:

1. Make it a habit to run the engine until it runs out of fuel. This helps stop problems from “modern” gas formulas, forming gum and goo in the carburetor.

2. Check the fuel filter and replace it if you’re not sure.

3. Disconnect the spark plug wire and “ground” it to the engine. Most small engines have a triangular “tab” for slipping the spark plug wire onto it.

4. Change the engine oil (dispose of the old oil properly). If you don’t remember when you changed it last, or just “checked” it, change it NOW.

5. Remove spark plug. If it looks oily, cracked, black, or just plain crummy, REPLACE it. If it’s ok, check the spark plug GAP – .020-.025 is typical. If you’re not sure, get a new plug and make sure it’s the right plug for your engine.

6. “Pickling” rings and valve, and cylinder walls, protection hint: Pour a TEASPOON of “Marvel Mystery” oil (any light oil will do) into the spark plug hole. (Don’t go crazy and overdo it.) Let it sit for a minute, then press your thumb over the spark plug hole (after making sure the spark plug wire is grounded to the frame. Caution: “Instant Shock Therapy” is very possible if it is not.) SLOWLY pull the starter cord, ONE TIME ONLY! You will feel a suction and then a pressure “poof” on your thumb. (If you don’t, it’s time for the repair shop engine doctor!) The oil is now distributed into the cylinder rings and other engine parts to keep them from freezing up and happy while in storage.

7. Make sure weeds and twigs are not hanging in or on the fan.

8. Clean the air cleaner (foam type) and replace if needed.

a) For the foam type, wash in light soapy water, squeeze and let dry. Oil it up, squeeze out the excess oil and re-install.

b) For the paper type, blow carefully on the inside of the filter with an air hose. If it’s too clogged, replace it.

9. Re-install spark plug and wire.

10. Wipe the entire engine down removing dust, dirt and goo. You paid a lot of money for it, take pride in it by keeping it clean.

11. Don’t “adjust” those little screws by the carburetor, unless you’re SURE of what you’re doing. Those “adjustment” screws normally don’t “un-adjust” themselves. Consult the engine manual for adjustments and tweaking for altitude load or for poor fuel, only after everything else checks out, (clean air filter, etc…)

Hint: After dredging, high banking, etc…, I cover the engine, after it cools, with a plastic garbage bag in case it rains! That way, it will start easily the next time.

Now you can get back to dreaming and planning your next expedition with reasonable confidence that y our engine will run when you get there.

See you on the river!