01 FAQs on Soil Sampling With Augers

8/3/2019 01 FAQs on Soil Sampling With Augers

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Frequently asked questions Soil sampling with augersGeneralquestions................................ ................................ ................................ ................................ .... 2

Q: Can the metals, used in an auger, contaminate a sample?....... ......................... ...................... ........ 2Q: Our guidelines say that I need to take samples with a stainless steel auger. Eijkelkamp augers aremuch stronger and drill much better than stainless steel material but what to do ? ...................... ........ 2Q: How many meters of extension rods can I leave coupled when doing a deep drilling? ...................... 2Q: How do I collect a sample from various soil types ? ......................... ......................... ...................... 2Q: How can I effectively decontaminate sampling equipment ? .................... ...................... ................. 3Q: What happens if I drill through an electric cable isolation?....................... ...................... ................. 4Q: What does exactly mean disturbed or undisturbed soil sampling ? ...................... ......................... ... 4Q: In our country we are only just starting with environmental research. How do we take soil samples ?5

Questions on augers and (ergonomic) handles ................................ ................................ .................... 6Q: In what soils can I use a Dutch auger ? ........................ ...................... ......................... ................... 6Q: Why are there so many types of Edelman (Dutch) augers ? ......................... ......................... ........... 6Q: The ergonomic top piece to drill with augers uses auger bottom parts with extremely short tubes. I

have augers for a normal length auger so they have longer connection tubes. Can I use the olderbottom parts with the new ergonomic handle ? .................... ......................... ......................... ........... 7Q: I have difficulties in drilling in heavy clay soil and pulling up a filled auger. What do I do wrong ?..... 7Q: Does an auger need any maintenance? ......................... ......................... ...................... ................. 7Q: The bayonet coupling is very handy and rapid but sometimes, specially if used under water, it doesnot want to move anymore. How do I solve this problem ? ..................... ......................... ................... 7Q: How deep can I go with augers ? ....................... ...................... ......................... ......................... ... 7Q: The ergonomic handle is expensive. Why should I buy it ? ....................... ...................... ................. 8Q: What is the main function of a spiral auger and the stone catcher ?.... ......................... ................... 8

Question on piston samplers ................................ ................................ ................................ .................. 8Q: There are two piston sampler kits. What is the difference between the two?........................ ........... 8Q: How do I take a sample with a piston sampler ?........................ ......................... ......................... ... 8Q: When it was new my piston sampler operated in a perfect way. Now I have the impression that Iloose the sample more often when retrieving and that it is more difficult to get a full length sample..... 9Q: Can I take a peat, clay or loam sample with a piston sampler? .................... ......................... ........... 9

Questions on bailer boring ................................ ................................ ................................ ..................... 9Q: When can or should I do bailer boring? ......................... ......................... ...................... ................. 9Q: How deep can I do a bailer boring?....................... ......................... ......................... ...................... 9

Questions on motorized soil auger sets ................................ ................................ .............................. 10Q: When can I use the motorized soil augering set 03.05SA? ....................... ...................... ............... 10Q: When can I use the motorized soil augering set 03.05SB? ....................... ...................... ............... 10

Questions on percussion drilling................................ ................................ ................................ .......... 10Q: When can / should I use this drilling / sampling technique?.............. ......................... .................... 10Q: Can I go to 16 m depth with percussion drilling equipment? ...................... ......................... ......... 10Q: When do I buy a motor powered hammer and when an electrically powered hammer ? ................ 11

Q: Do I choose the wedge connection or the RD-32 connection? .................... ......................... ......... 11Q: Can I take a sample in a liner ?.................................... ...................... ......................... ................. 11

Questions on the lost cone drilling set and the Direct well 10.100 ................................ .................. 12Q: How does the lost cone drilling technique work. ..................... ......................... ...................... ...... 12Q: What can I do with the lost cone drilling set?.......................... ......................... ...................... ...... 12Q: What is a Direct Well and how does it work?...... ...................... ......................... ......................... . 12Q: When and how do I install a Direct Well?.......................... ......................... ......................... ......... 13Q: Can I install a Direct Well with sounding equipment? ...................... ......................... .................... 13

Questions on Sonic Drilling ................................ ................................ ................................ .................. 13Q: What techniques can I apply with Sonic drilling? ..................... ......................... ...................... ...... 13


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General questionsQ: Can the metals, used in an auger, contaminate a sample?

A: The augers are made of high tensile strength forgeable iron-manganese steel. As long as thesurface is kept clean from polluted soil, grease and so on you can take reliable samples on bothmacro parameters as well as micro parameters like cadmium, copper, vanadium, chromium, nickeland so on. The only exception is that you cannot take samples for iron and manganese analysis if thesurface of the auger is heavily oxidized for instance after long term storing in a humid environment.You may clean such an auger by rubbing it with sand or just using it to drill a few meters before youstart taking samples. To clean augers from oil you may use neutral baby shampoo and rinse it withwater or, again, use it for a few meters of drilling.

Q: Our guidelines say that I need to take samples with a stainless steel auger. Eijkelkamp augersare much stronger and drill much better than stainless steel material but what to do ?

A: "Early" tests (around 1988), performed by a Dutch (largest) environmental research company anda Swiss (state) organization showed that neither stainless steel, nor Eijkelkamp' non stainless gougesand augers was able to contaminate a soil sample with detectable levels of steel componentscontaminants like nickel, chrome, vanadium etc. The reasons are simple: The Eijkelkamp steel (socalled iron-manganese steel) AND stainless steel are so hard that the amount of abrasion betweenthe auger and soil is too little to get a detectable level in a soil sample.

If any of those two materials would be able to cause a problem in this way it would be the stainlesssteel product rather then the oxidizable iron ! The reason, again, is simple: Our iron manganese steelcontains only a trace of vanadium (0.1%) whereas stainless steel (304 type) contains 18.5% and 9%nickel ! So if a material would be able to contaminate a sample with a toxic metal then it would bethe stainless steel. The fact that researchers showed that it doesn't, shows that even stainless steel isacceptable (and not the other way around !!). Even a moderately oxidized 'ordinary' steel auger is not

able to contaminate a sample simply because it does not contain toxic contaminants in quantity inthe oxides. If any rust has appeared by incorrect storage the cleaning procedure followed by mostfield workers is to twist the auger a few times in local soil to rub off the rust. Further cleaning as withother sample material. Do not use detergents with a high pH to prevent zinc from the extension rodsto go in solution ! Baby shampoo is perfect to wash of any oil residues.Beware of zinc (or paint) plated augers a.s.o. Zinc is very soft and the layer of pure soft zinc (or paint)will be rubbed off quickly and will bias analysis results in detectable levels !

Q: How many meters of extension rods can I leave coupled when doing a deep drilling?A: Four meters can be held horizontal without that you run the risk that they bend. This needs asecond person to hand over the 4 meter long extensions to the driller. Two coupled meters can beconnected and disconnected with one hand. Manipulating two coupled rods at the time allowsdeeper drillings when you are alone.

Q: How do I collect a sample from various soil types ?A: Firstly put a sheet of plastic on a hard surface or wooden plate.If you are drilling in a sand soil you open your jar and collect the sample in the jar by scraping it in thejar with the cap or a spoon.For a cohesive soil type like clay you open the jar and push it upside down in the clay until the jar iscompletely filled. Clean the rim with your finger or a spatula and close the jar.


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Q: How can I effectively decontaminate sampling equipment ?Situation: Effective decontamination of a wide range of sampling equipment to be used for samplingin coal tar residues contaminated water/sediments - in a waste dam of several decades old at a large

iron/steel works - the exact concentrations are unknown - thats why we are sampling.

The range of samplers to be used (for the variety of material conditions on site) are:

Hand augersBailer boring equipment & temporary casings & bailersStainless steel bailer for water samplingSample gutter for sample presentationMultisamplerDividable piston samplerBi partite gouge auger setPeat sampler

THE ANSWER

Concerning the question on decontamination of equipment:

Tars are difficult matter for decontamination !Hot diluted Deconex (20.05.29) is a very aggressive cleaner (zinc will go into solution !)I will separate two groups of products:

A: The products used for soil or sediment samplingA1: Stainless steel productsA2 Steel productsA3 Plastic products

B: The products for groundwater samplingB1 Stainless steel or glass productsB2 Plastic products (non-disposable)

A1: Stainless steel products can be cleaned in a hot (60-95 C) concentrated Deconex solution(concentration indicated on the bottle). In case of very heavy contamination (greasy layer on theproduct) a cloth with pure acetone (alternative naphtha / paraffin where you wash clothes in) can beused in advance of the Deconex. Of course a steam cleaner is effective too. Rinse with clean water tofinish with.A2: Use the acetone option and after that baby shampoo + water rinse.A3: Forget the acetone (except for Teflon where it can be used). Naphtha / paraffin can be usedhowever. After that Deconex or (if less dirty) shampoo + rinse.

B: General: Use disposables when possible. Except when used in a layer with pure product theconcentrations will be very low.B1: Use the hot Deconex for an hour or so. Then rinse.B2: The most delicate group: Through their micro porosity you may clean the out + inside but not theinterior (intermolecular space). Use the hot Deconex (attention not to destroy the product byoverheating the product). Then rinse with ample water. Expose to warmth (sun, outside) for a fewdays to chase out the volatiles.

Please consult the decontamination documents in the additional info section (not in FAQs) fordecontamination procedures as recently described in a US magazine.


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Q: What happens if I drill through an electric cable isolation?A: Nothing. Since the auger body also is in contact with the surrounding soil, current will be deviatedfrom the cable to the earth instead of to your body. You will hear nasty sounds and even see a white

flame blowing out of the bore hole. This will shock you but without being 'shocked'. We do howevernot exclude that in bone dry soil (that does not conduct electricity so easily as moist soil) it is wise towear isolating rubber foot wear, gloves and use a handle with isolating protection.

Q: What does exactly mean disturbed or undisturbed soil sampling ?Sampling equipment compared to degree of disturbance for three types of soil samplings: Soil; soilunder the groundwater table and sediment. Also see the Product Information Brochures or manualsfor further info on equipment and applications. Table 2 lines up equipment compared to degree ofdisturbance and sampling depth. Table 1 shows the legenda.

Table 1Legenda for degree of disturbance

Degree ofdisturbance Description of phenomena Main application ofsamplesUndisturbed soil in-situ = research in profile pit Undisturbed soil structure

description

Undisturbed sampled soil in the best sampling tool imaginable(coring rings)

Laboratory measurementson water/air permeability,volumetric soil moistureand density determinationsa.s.o.

Slightly disturbed Layers, roots, soil concretions perfectly visible butsome compression or (water/air) leakage at sides ofsampling ring or tube.

Accurate soil profiledescriptions, accurate rootdistribution, soil structure,volumetric soil moisture

content, chemical samplingon volatiles, faunacountings

Semi disturbed Soil structure can still be read (layers, roots,concretions, local colour variations, fauna) but moresevere compression and damage to soil structure

Soil profile description, rootdistribution (rough)

Disturbed Information on roots, soil structure, concretions,local colour variations is lost. Colour variations overlayers (> 10 cm) can still be determined

Rough soil profiledescriptions, roughestimations on permeability

Completely disturbed Colour variations over layers > 10 cm < 100 cmcannot be read anymore (soil structure completelylost, soil mixed over layers)

Not for sampling; only tomake holes !


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Table 2

Sampling equipment compared to degree of disturbance for three types of soil samplings: Soil; soil undergroundwater table and sediment.

Type of soilmaterial Undisturbed Slightly disturbed Semidisturbed Disturbed CompletelydisturbedSoil Coring

rings 07.xxand 08.09

Coring tubes (04.11, 04.14,04.15, 04.16, 04.17)Soil column cylinder auger05.07.All gouges > 15 mmincluding percussion gouges04.xx.Grass plot samplers 05.0305.10.Root samplers 05.01/02Profile samplers 05.08/09

Edelmanaugers01.02 inmoist soilGouges < 15mm diam.

Riverside01.04, stonysoil augers01.06 in allsoils. Edelman(Dutch)augers 01.02in dry soils

Helicoidal /spiral augers(flighted)augers01.08 +

03.05SA andSB

Soil undergroundwater table

Coringrings 07.xx(impossibleinsaturatedsand)

Coring tubes 04.11, 04.14,04.15 04.16, 04.17 (in sandcore catcher will benecessary).Piston samplers 01.09.Aqualock 30.6x.Only in cohesive soils: Allgouges > 20 mm includingpercussion gouges.In peat soils use Peatsampler, Dachnowsky probe,root auger or profile sampler

Edelmanaugers01.02(saturated sandswill drop outof auger usepistonsamplerthere)

Riverside01.04, stonysoil 01.06 inall cohesivesoils

Bailers (all)

Sediment SedimentcorerBeekertype04.23,Multisampler 12.42,Vrijwitsampler04.22

Peat sampler 04.09

Dachnowsky probe 04.08;Aqualock 30.6xPiston sampler 01.09,

Free fall

corer 04.29

Van Veen

grabs 04.30

Bailers (all)

Q: In our country we are only just starting with environmental research. How do we take soilsamples ?

A: The 01.11SO kit is meant for general soil sampling. If the augers / gouge orpiston sampler are clean (that is why they are sold unpainted) the samples obtained can be used formacro as well as micro-parameters.Trace metals and the other parameters that you mention are relativily easy to sample since they arenot volatile. Normally samples are taken at 50 and 150 cm depth up till a depth of some 5 meters ifno monitoring well is installed. If sampling for airborne deposits the top soil is sampled.It would be logical to include searching for volatile components (like toluene and benzene) since theyare omnipresent in badly exploited gas stations / refineries / tank parks and so on. They will pollutethe groundwater in the region if the pollution arrives in the groundwater. Also the use of tri and tetra(degreasers used in galvanisation plants and dry-cleaning of clothes) has lead to dangerous soilpollution.


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When searching for volatiles sampling is started at 1 m depth (the top soil is too much vented bywind and heat). Two options for sampling are reasonable: Taking core samples with the 04.16 kit in apre drilled hole (pre drilling is done with the 01.11SO kit). Otherwise you may follow the way that will

be pre-scribed in the ISO standard on soil sampling (for pollution). Then you take a few soil samples(for instance over a depth of 50 cm) with one of the augers and cover it with aluminium foil until thenext step is taken. The next step is to immediately fill a small glass vial with the soil from the fivesamples you took over that 50 cm depth. Then (also directly in the field) laboratory-grade methanol isadded (about 50%) to extract the volatiles from the sample. In the lab the methanol is analysed.If a soil sample is taken with the 04.16 kit the volatiles cannot evaporate (sample is completelyenveloped in diffusion proof stainless steel). The samples are cooled and transported to the laboratoryand then subsampled with a small gouge from both sides of the core. This is analysed on thevolatiles.If sampling is difficult because of bricks and stones normally the next step before renting a shovel orpay loader is investing in percussion drilling equipment 04.19SD (see brochure P1.21 of catalogue orwebsite).Be aware of the fact that soil pollution is one but groundwater pollution two ! If groundwater is close

(


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Q: The ergonomic top piece to drill with augers uses auger bottom parts with extremely shorttubes. I have augers for a normal length auger so they have longer connection tubes. Can I use theolder bottom parts with the new ergonomic handle ?

A: Theoretically that is possible. Largest problem is that the height at which you will initially start theaugering (so at soil surface) is quite high. At the moment you are 30 cm deep this disadvantage is notfelt anymore. The only disadvantage left then is that the depth markings on your ergonomic do notcomply with the depth for which these markings are meant. If you want to spend a minimum ofmoney to start working with the ergonomic handle you may buy the handle with only one(combination) type auger.

Q: I have difficulties in drilling in heavy clay soil and pulling up a filled auger. What do I do wrong ?A: Firstly you are probably overfilling the auger ! If you do that in a clay soil you are creating a piston-cylinder combination that will cause big trouble ! And it gets worse if you get below the water table.So:1. Do not overfill the auger. If you did however, lower while rapidly twisting it an empty auger

(preferably a coarse sand type) into the borehole until you touch the bottom of the borehole. Pullthe auger out and empty it. Now you have cleaned the wall of the borehole of excess soil.

2. Very effective is to make, at a certain depth the borehole somewhat larger with an 8 or 10 cmauger. This will free space and will make lifting out the auger for the next coming meters easy.

3. In wet clay soil keep extension rods clean. If not they will become too slippery.4. If a clay is so soft that suction pulls it partly out of the auger consider using a combination type

auger or even sand type auger. The blades hold the soil much better.5. In soft soil you may consider using the soft soil auger ! The auger body has twice the length of an

ordinary Edelman auger and works much quicker.6. To be able to tap the sample out of the auger body do the following: Push/twist the auger until it

is almost full. Then pull it up for ten centimeters or so. Then push it down back in the boreholewith your FULL weight WHILE doing a short sharp clockwise twist of not more than 30. Thenpull it up. This procedure has loosened the original sample from the point and the blades. When

you tap the auger gently on a piece of wood the sample will loosen from the auger easily.7. Pull the auger (or any other tool) out of the soil by putting your upper leg under the handle andusing your leg as a jack. Since the ergonomic auger can be adjusted to three ideal heights thiscan save your back.

Q: Does an auger need any maintenance?A: No. Just allow it to dry after use and store it in fairly dry area.

Q: The bayonet coupling is very handy and rapid but sometimes, specially if used under water, itdoes not want to move anymore. How do I solve this problem ?

A: Pouring clean water into the sleeve while keeping the extension rods vertical will flush out anyblocking sand. A few taps on the side of the sleeve will make it move; no doubt !

Q: How deep can I go with augers ?A: Depends on: Soil type, number of available extension rods, availability of different auger bodies(specially types; also sizes), groundwater level (specially if you are drilling in sand layers) and not toforget experience and available time !The deepest drilling that was recorded with bayonet coupling type Eijkelkamp augers 7 cm was 40meters of which the last 5 meters below the water table (in Catalonia, Spain). This was done in a veryeasy soil type by a German team that did not use a tripod. Tripod assisted deep drillings up to 25meters were recorded from Sudan. In the Netherlands generally 5 to 7 meters is considered a realisticdepth nowadays considering ergonomic items (weight) and efficiency of drilling teams. Deeperdrillings are then reserved for drill rigs. Once a sand layer under the water table is reached the augerwill come out empty and other drilling techniques (like bailer boring) are needed anyway.


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Q: The ergonomic handle is expensive. Why should I buy it ?A: To save your hands, your wrists, your elbows, your shoulders, your spine and your legs ! Thereasons: The ergonomic top piece can be adjusted to three ideal working heights, the horizontal

handle itself is larger than a normal handle which reduces the necessary twisting force. The horizontalhandle itself is at the end fitted with large balls that reduce internal forces in hand and wrist. Due tothe fact that the handle is not turned around but twisted in small strokes forces on spine, elbow andshoulders are reduced largely. The spine will also be very content that you do not need to bend overto twist the auger or pull it out of the soil since the handle allows adjusting for three workingheights. In the Netherlands, since a few years, employers pay the salary of sick employees for the firsttwo years of their illness. You can imagine that this boosts investments in ergonomic improvementslike the ergonomic handle.

Q: What is the main function of a spiral auger and the stone catcher ?A: See the soil as your teeth after a good meal. The spiral auger is the tooth pick and the augers thetooth brush. Use the spiral auger to loosen stones down in the borehole. Use the augers (morespecifically the riverside and stony soil augers) to remove the loosened soil from the borehole. Thestone catcher can be used to remove oversized stones from a borehole.

Question on piston samplersQ: There are two piston sampler kits. What is the difference between the two?

A: Piston samplers (all types) work in saturated sand and other very weak/fluid material with very lowfriction. The piston prevents friction of the sample when it slides into the samplers tube. The pistonalso holds the sample in its place (by a vacuum) when pulling up the sampler. Of course the piston'srod should be firmly held then.The traditional kit 01.09SA includes as basic tool a 2 meter long piston sampler (net sample length).This is the maximum length an average tall person can handle. You must push out the sample directly

in the field in a sample gutter supplied with the sampler. If you drop or otherwise force the samplerthe tube may become unusable and the sampler must be replaced completely.The more recently developed kit 01.09SB features three exchangeable tubes of 0.5, 1.0 and 1.5 netsample length with three accompanying piston rods for these lengths. Of course there is also thenecessary top piece (collar) and pistons going with the kit. The 1.5m long sampler is appreciated bypeople that have difficulties in handling the 2 meter long version. You may leave the sample in thetube for later analysis at home. Of course you will need to have more tubes of that length andpistons then.You may also assemble a bare 1.5 m long piston sampler and leave the other lengths if you wish. Youwould in that case need parts: 01.09.03b (the collar that connects the tube with the extension rods)+ 01.09.06 (sample tube 1.5 m) + 01.09.10 Piston rod 1.5 m + 01.09.00.01 (piston). Extension rodsand rope and so on is not mentioned over here.

Q: How do I take a sample with a piston sampler ?- Wet the inside of the coring tube / piston with water- Lower sampler with piston in lowest position- Upon hitting the water bottom pull up the sampler for at least some twenty centimeters- Stretch the piston cord without pulling the piston up and block it, for instance, by stepping

on the cord with your (left) foot.- Push down the sampler. If it blocks try pulling the piston rod with short strokes to diminish

the friction of the sample in the tube. However the resulting position of the piston shouldstay at a stationary level.

- Pull up the sampler together with the piston cord.


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- Empty the sampler by lying it in a gutter and pulling the sampler towards your body whileholding the piston in a stationary position.

- See the manuals of this equipment for more detailed info on sample retrieval and

applications.

Q: When it was new my piston sampler operated in a perfect way. Now I have the impression that Iloose the sample more often when retrieving and that it is more difficult to get a full lengthsample.

A: Put your (or another persons) hand on the bottom end of the sampler and pump up and down thepiston. In both ways it should apply correct suction or pressure. If not renew the piston after checkingif there are no bumps in the steel tube !

Q: Can I take a peat, clay or loam sample with a piston sampler?A: Un compressed peat or unripened clay would not be a problem. Ripened or compressed peat oreven loam would be a problem simply from the penetration resistance point. Use a Sediment corerBeaker sampler type there since this can be hammered.

Questions on bailer boringQ: When can or should I do bailer boring?

A: More then 90% of mankind is living in river deltas and valleys. A lot of these soils are sands underthe groundwater table. There augering does not work simply because the material flows out of theauger. In that situation you may widen the borehole to 100 mm and lower a casing in this hole untilthe level were you arrived drilling with the auger (or other) technique. Then you connect a bailer tothe extension rods (or cable if you are drilling larger or deeper with the help of a tripod). The baileritself is a narrow bucket with a large foot valve at the bottom. If you quickly move it up and down inthe mud standing below the casing the casing will fill and the casing will lower by its own weight, by

the suction of the bailer and if necessary helped by your weight if you start standing on the casingtube platform. Each time the bailer is filled it is pulled or winched up and emptied while refilling thecasing with a sufficient quantity of water to give backpressure to the sand under the casing. Thisprevents sand from re-entering the casing. Specially if the sand also holds stones this should beavoided. The bailers cutting shoe (valve) should operate at the same level as the cutting shoe of thecasing for maximum drilling efficiency. Therefore a good visible marking should be put on the cable.The upper rim of the extension rods can be used as reference when working with rod operatedbailer. When arriving in a stony layer a bailer with rubber foot valve or even smaller size bailer withrubber foot valve should be used to prevent lifting an empty bailer.Arrived at the desired depth one places the monitoring well or takes a core- or piston sample and lifts(by means of a jack or tripod) the casing out of the borehole. The material poured out of the bailercannot be used for profile description since it is too much mixed. When the bailer is blocked by a stiffclay layer or loam on may use an ordinary auger or gouge to take a sample or drill through this layer.If a large size casing was used one can, once drilled through the 'blocking' layer slip a smaller sizecasing down the larger casing to recommence bailing in the second sandy layer. Two clamps enabledisconnecting the casings. A good manual accompanies a kit. There are faster drilling techniques butthere are only a few techniques that allow the accurate installation of monitoring wells or accurate,even undisturbed, samplings.

Q: How deep can I do a bailer boring?A: Depends on weight and size of the casing. Weight and size of the bailer (with consequently theuse of a tripod to lower and lift the bailer). soil types, depth of the sand layer below the groundwatertable (friction on the side of the casing), steel or plastic casing (friction again) and experience of thedrilling crew.


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For the 01.12kit one may say that in an average saturated sand layer one may 'penetrate' by bailingsome three to four meters into the saturated sand layer. This means that if your water level is minus 7meters that you may auger to that depth with a ten cm auger then lower a casing and continue until

you are 10-11 m deep and install a well or take samples all along the drilling depth. In this case youwould need more casings and extension rods. When water table + fluid sand is at minus 1 m bailingto 5 m depth (4 m of friction) is already hard work. Of course with the larger / heavier casings youcan go deeper. For instance: With extensive experience and 'good' soil 50 m can be reached with a120 mm steel casing.

Questions on motorized soil auger setsQ: When can I use the motorized soil augering set 03.05SA?

A: The 03.05SA is meant for drillings in non-fluid soils. So you cannot drill through a water saturatedsand layer. You need three people; one to operate the winch; the two others two hold the engine

with drill. You also need patience since it is not a rapid drilling technique. Do not expect samples. Thesoil will be spiraled up and will be very mixed. It is just to get a hole 8 cm in diameter. Of course youcan take core or other samples from the bottom of the borehole. For this the hole drill string must bewinched out of the hole.

Q: When can I use the motorized soil augering set 03.05SB?A: Same as SA only the set is enriched with bailer boring equipment to be able to do an additionalbailer boring once a fluid sand layer is reached. Note that larger spiral flighted augers are added tothe set too to allow lowering casings.

Questions on percussion drilling

Q: When can / should I use this drilling / sampling technique?A: If working with an auger or a hand operated gouge becomes fighting then it is time to thinkabout investing in percussion drilling equipment. It penetrates rubble, debris, bricks, stones, stonysands, moist glacial loams and so on. It does not penetrate concrete (too compact; too hard), thickwood or roots (too fibrous), metal sheets and rubber (too plastic) and dry soil types without anyporosity. The reason of the latter is that the gouges' own volume (the cutting ring) must push asidethe soil. If the soil has no pores AND no porosity then there is little or nothing to push and you canbetter skip to a cheap riverside or stony soil auger. For the rest a percussion drilling set will givefantastic sampling results and a perfect cylindrical borehole in extremely stubborn soils. Clays withoutstones can better be drilled by hand augers (or mechanical drill rig) since emptying the gouges can betough with clays. A reason for buying would also be that you can use the most expensive parts to

hammer down and pull out a small diameter hollow casing with lost point to install small diameterwells or dynamite for seismic explorations. See also the FAQ's on the lost cone drilling set.

Q: Can I go to 16 m depth with percussion drilling equipment?A: You can but you shouldn't ! The main principle of the sets offered is that you do a stepwisesampling; each time taking a smaller diameter gouge. So you start with a gouge 100 mm. This leavesa hole 100 mm in diameter 1 m deep in which you can DROP a 1 m long 75 mm gouge. This gougeneeds to be pulled out with heavy equipment only for one meter and not the two meters that youdrilled deep now ! After one meter of pulling you can lift the gouge out easily by hand. Once liftedout you can DROP a 2 m long 60 mm gouge, hammer it in the soil and pull it out. Then drop, fittedwith one extension rod, a 2m long 50 mm gouge, hammer it down, pull it out for two meters and lift


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it out by hand for 2 meters. Then fix two extension rods on the 2m long 40 mm gouge and lower thisinto the borehole half way. Twist an extra three rods on it and hammer it in the layer from 6 to 8meters. Anything deeper will demand extreme patience because you not only will have to use the

power hammer to hammer the gouge in the not sampled layer but also to hammer it through thelayer that was already drilled in. To arrive at 16 m depth you would have to use the 2 m long 40 mmgouge for the 6-8 m stretch, 8-10 m stretch, 10-12 m stretch etc. To sample the last stretch from 14-16 m you would have to lift on and off the power hammer for 11 times. Each time screwing a 1 mlong extension rod on the drill string. This demands for extreme patience. We suggest the Sonicdrilling equipment for deeper drillings or very many shallow drillings.

Q: When do I buy a motor powered hammer and when an electrically powered hammer ?A: Generators, which are essential to power the electric hammer are heavy (50 kg) but they consumerelatively little fuel, are reliable starters and do not smoke since they work with a 4 stroke engine.You take (super unleaded) petrol at every gas station. The electric hammer however is much lighterand more compact than the 2-stroke motor powered hammer. The two stroke motor hammer is agenerator and power hammer in one. Its weight is substantial and you will lift it on and off the gouge

with two persons. It is more expensive than a generator + electric hammer. Two stroke enginessmoke, ask for oil mixed petrol and are less reliable starters. In general they also ask for moremaintenance than electric equipment or four stroke engines. But you do not need to transport agenerator. Safety of electrical equipment can be assured with the isolation guard. This tests thegenerator, extension cables and all internal wiring of the electric power hammer 1000times/secondand switches off the tension in case the tiniest loss of voltage is noticed. The power hammer isdouble insulated so earthing is not necessary and so useless. You may earth the generator since it willadd some extra safety. The isolation guard cannot physically stop the generator. Of course theelectrical parts of the generator that we selected for this equipment are very well isolated. So thechoice; electric or motor power is (still) up to you.

Q: Do I choose the wedge connection or the RD-32 connection?A: Compared to the formerly used M20 screw connection the wedge connection is extremely reliableand relatively straight forward to use. As long as you do not drop drill strings (gouge + someconnected rods) on the ground or bend the drill string in the borehole the equipment will be durableand perform as desired (dropping or bending will overstress the thinner male parts of the wedgeconnection with a breakage risk as result). The wedge connection set weight is within sympatheticlimits. A disadvantage of the wedge connection is the vertical 'play' when pulling out a drill stringfrom a borehole which causes the need for more strokes with the mechanical rod puller before thegouge comes above ground. This is specially important when often drilling at larger depths.RD-32 equipment is incredibly strong and reliable and is made to last. It is heavy and you needheavier and more expensive rod pulling equipment and side tools as wrenches. In general peopleprefer RD-32 because of its convincing almost stubborn drilling qualities. One tip on beforehand:Always keep drilling rods with screw connection tightly 'closed'. This is done by twisting the powerhammer lightly to the left (left hand thread) while drilling. Again, the final choice is up to you.

Q: Can I take a sample in a liner ?A: Yes. There is one gouge with an outside diameter of 63 mm. This gouge has a detachable top andbottom piece and includes a core catcher and a PVC liner 50 mm.


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Questions on the lost cone drilling set and the Direct well 10.100Q: How does the lost cone drilling technique work.

A: That is quite simple: A wetted (cheap cast iron) point is slipped into the bottom part of a narrowcasing. Most of the time one of the two O-rings is removed from the lost point. The O-ring issmeared with a bentonite slurry. Each meter is hammered or vibrated (with Sonic equipment; which isdozens of times faster than hammering) into the soil. After each meter you add a meter. Arrived atdepth you lower into the empty casing Depending on used hammer/vibrator and soil types you willreach from a few meters to thirty forty meters or more). In this casing you may lower a well (formonitoring or to measure local pressure height) or explosive (seismic research) or sensor (geotechnicalresearch or other). Then the casing is filled with water; filled with bentonite plugs (in most cases) andpulled out with special pulling equipment. The lost point stays behind. The plugs (at least the partthat is wetted with groundwater) will swell in 48 hours and the installation is ready. The point will dono harm. In this reduced environment it wont even rust. For your information: We have sleek

(smooth on in and outside) casings (diameter 40 x 53 mm) and heavier ones 40 x 63. The latter beingsmooth at the inside but thicker at the screw connections. They work with the same lost point.Further data in the catalogue with the Sonic drilling equipment info.

Q: What can I do with the lost cone drilling set?A: Drill through layers which cannot be drilled by augers or bailer boring, spiral augers and so on.Specially stony layers or layers with debris are popular. But you may use the technique with any soilexcept those soils that have little porosity. In certain fine sands penetration may be too slow. In heavynon plastic (fairly dry) clays it does not work fast either. You have a technique here with which youcan install monitoring wells almost in any situation. You may install a traditional small diameter (32mm outside) well but in a fluid soil you can either apply filter sand (the casing is too narrow to allowfor this) nor bentonite pellets. That is why the Direct well was invented. The lost cone drillingtechnique does not result in soil samples so a profile description must be made separately. To prevent

oil pollution do not use any oils or greases on the casings screw connections. Remove all greasesprior to drilling if in doubt. You may use naphtha or acetone for this a hot detergent / steam cleanerwill work as well. You can grease the screw connections with a slurry of bentonite.

Q: What is a Direct Well and how does it work? A: A Direct Well has three typical components which distinguish it from normal wells.a) The blind pipe is narrower than the slotted (screen) section. In fact it is so narrow that a tube 10 x

12 mm PE can be used in stead of a stiff pipe.b) The slotted section is composed of 1 m slotted HDPE pipe with a special shape on the outside

which keeps the already mounted filter gauze a few millimeters away from the slots. Thisprevents plugging of the filter gauze and slots and increases greatly the filtering capacity of thewell. This pre-packed filter makes the use of filter sand unnecessary. Of course the top of the pre-packed filter is fitted with a tubing connector.

c) To plug all layers, hollow thick bentonite staves are slipped over the tubing (blind pipe) over thefull length of the tubing. After pulling out the casing these will swell and will close impermeablelayers and the space left behind by the casing.

d) To measure the water level a special water level sensor is available (11.03.18) with a 8 m longcable.

e) To sample the well a peristaltic pump can be used until water levels 8 m with either tubing 6 x8 mm slipped to the bottom section of the well or connected directly to the 10x12 mm tubing ofthe well itself.

f) A foot valve pump diameter only 9 mm outside with tubing 6 x 8 mm PE can be used until 30 mdepth to sample wells with deeper water levels.


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Q: When and how do I install a Direct Well?A: How ? Once the casing or sounding rod are at the desired depth: Open, at the end of the tubingconnector, the protecting foil, enveloping the pre-packed filter. Slide two bentonite plugs over the

end of the 10 x 12 mm tubing (this will act as ballast when lowering the pre-packed filter into thecasing). Slide the PE tubing 10 x 12 mm over the connector. Now remove the protecting foilcompletely and slip the filter and plugs and tubing into the casing. If the plugs are somewhat bananashape break them. Try to avoid plying the tubing. When hitting the bottom of the casing (the lostpoint) add bentonite plugs until they stick out of the casing. Fill the casing with water. You may alsofill the casing prior to filling them with the plugs. Then install on the ground the rod pulling deviceand wedge clamp. If you are not very deep or the lost point is sitting in a soft layer be sure that thelost point will free itself from the casing. This is done by heavily pushing the bentonite plugsdownward at the moment someone else starts lifting the casing. Then all casings are removed. Whatwill be left is a tubing sticking out of the soil. You may finish this tubing just below the soil level witha special kit that allows adapting the monitoring well cover 10.02.30 with a foot plate and a specialvented plug for the tubing. The kits number is 10.04.32.

Q: Can I install a Direct Well with sounding equipment?A: If the hollow casing is spacey enough has no narrowing inside and the casing can be fitted with alost point it is OK. Diameter should be 40 mm inside minimum.

Questions on Sonic DrillingQ: What techniques can I apply with Sonic drilling?

A:a. You can vibrate down, with often incredible speed, a casing fitted with a lost point. In the casing

you may install a Direct Well, a small diameter (32 mm O.D.) classical well, an explosive forseismic explorations, any sensor < 35 mm in diameter.

b. You can vibrate down, prior to a lost point with casing a long liner sampler fitted with a corecatcher.

c. You can vibrate down, specially meant for under the groundwater level, an Aqualock sampler.This is a long tube with a water pressure operated piston. Upon use the piston is firmly blockedwith 100 bar water pressure at the bottom end of the tube (max 4 m long). Then the sampler isvibrated down until the level where soil has to be sampled. This may vary from soil surface untiltenths of meters of depth. Arrived at sampling depth a rod is lowered in the casing and a valve isopened allowing the water on top of the piston to flow out of the tube. This will only starthappening when the sampler is vibrated down. By inertia effects the piston stay at the originallevel and the sampler is filled with sample. Once filled the rod is removed and the valve closes.The piston will now act as a vacuum that holds the sample while the sampler is retrieved. Onceabove the ground the chamber between piston and valve is pressurized with a normal highpressure cleaner. This will expel the sample which can be collected in a half round shaped liner orfull round liner.

d. The vibrations can be used to retrieve the casings with even less effort than vibrating them down.What you can vibrate down you will be able to get up again. With traditional low frequencyhammering this can be a big frustration.

e. A Sonic drill mast is also equipped with a rotation function. This has two advantages:1. You can drill through plastic clay layers. In these layers the effect of the sonic vibrations arelost for a large part. Added with rotation you will be able to drill through these stubborn layers.2. Connecting and disconnecting casings (which is the most important time factor since thedrilling itself goes so quickly) can be done efficiently.

Documents

01 FAQs on Soil Sampling With Augers