Drilling Methods

RD-n-P Drilling, Inc. has a variety of services that can be performed on a daily basis.  Following are some of the sampling and drilling methods that we use. 

Solid Flight Augering
This technique is used for shallow sampling holes; probe holes, or setting casing for rotary wash.  These sizes range from 4” to 12” in diameter.

Hollow Stem Augering
Used for sampling deep holes and setting a variety of wells.  (soil vapor, gas, monitoring, piezometers)  We also use larger hollow stem augers to set permanent casings for double and triple cased wells.  Sizes vary from 2 ¼” - 12 ¼”. 

Rotary Mud Drilling
This method requires drilling with a tri-cone bit (2 7/8” to 14”).  A bentonite powder is mixed with water and holds granular soils from collapsing being no casing is installed in hole.  This method is used for pressure meter testing, vane sheer testing, inclinometers, and slope indicators.  This method used for intermediate to deep borings or wells when hollow stems can’t be used. 

Air Rotary Drilling
When this method is used, it requires an air compressor to operate.  No water is involved for drilling.  We use 5” to 8” tri-cone bits with 4 ¼ ID (inside diameter) drill rods to prevent losing equipment in the hole.  This method is tedious because of the high pressure involved and usually performed in bedrock.

Air Rotary DTH (down-the-hole hammer) Rock Drill
This is a faster method of air rotary drilling that is performed in rock borings.  It doubles the production of rock drilling thus making footage rate less expensive.  Drilling sizes are 5 ½” to 8”.

Split Spoon Sampling
This method is most common in our business.  The spoons come in 2’ lengths and sizes of 2” & 3” and can be used in any soil conditions except rock.  A spoon is hooked to a drill rod and pounded in 18” or 24” increments with a 140 lb. hammer with a 30” drop.  The spoon is then pulled out of the hole, the top and bottom unthreaded, and is split in half where your sample is stored and then put into jars or baggies for analysis.

Undisturbed Sampling
Ways of getting this type of sample are by California Pitcher Sampler,  Austenberg Piston Sampler, Denison Sampler, or by Shelby Tubes ranging in size from 2” to 3”.  These methods require either water or pushing to retrieve your sample.  These samples are usually done in clay. When pulled out of hole, the samples are usually waxed on the ends and capped, then duct taped.  This is to prevent samples from drying out.

Rock Coring This method is done with a D-4 conventional barrel that comes in 5’ and 10’ lengths.  This type of coring is done when less than 20’ of core is needed.  This work is done in bedrock, usually requires clear water, and is spun in a high gear.  It has a diamond shoe to cut the rock and there is a catcher inside the barrel that catches the rock.  All rods are pulled out of the hole, barrel taken apart and rock slides out of inner barrel and put into core box.   Another method to core rock is by Wireline.  This is usually used for deep cores and does not require the pulling of drill rods to retrieve your rock sample.  You retrieve your inner barrel by a latchtube that is hooked to a wire that is dropped inside of your rods and pulled out.

Rock Pressure Testing This is done with twin packer or single packer systems from 2” – 6”.  This requires the packers to have perforated pipe in between packers and air tubing and also air tubing and ¾” solid pipe coming all the way out of the hole.  The air line is hooked to a nitrogen bottle and the pipe has a goose neck screwed into the top with a Chicago fitting leading to the pressure gauges.

Marine Drilling
This is done on small inland lakes, streams, and rivers.  This is done on our portable barge that supports our skid rigs.  Deep hole drilling that requires larger rigs can be done by renting barges in open water or jack up barges.

All Terrain Drilling
This is done in muddy or soft conditions where normal rigs can’t get.  This truck (ATV) contains big and wide tires to prevent the rig from sinking.  These rigs are transported by lowboy to get to job locations.  The ATV vehicle has a water tank, pump, HSA, and drill rods to perform any drilling necessary that the job requires.

Observation Well Installation
These wells are set through mud rotary or Hollow Stem holes.  Sizes range from ½” – 12”.  They usually have a minimum of 5’ of screen and is surrounded with sand and a bentonite seal.  After seal is put in, then it is grouted to the surface where a procover or flushmount is installed to protect well.

Special Instrumentation Installation
Some of the installations that we have performed are Inclinometers, Heave points, Boris anchors, Extensometers, Lysimeters, and Piezometers to name a few.  

Toxic Waste Drilling and Sampling
This type of drilling requires training (40-hr/8-hr) and Personal Protective Equipment (PPE).  Respirators are a strong possibility in this drilling.  Most of these sites are landfills, chemical plants, and nuclear sites.  This type of drilling is done as the same as any of the above listed methods.  The soils are barreled and are moved to designated areas for disposal by a special waste hauler.

CME Continuous Auger Sampling System
This method is used with a 5’ spoon inside of a 3 ¾” HSA and the sample is collected while the auger is drilling.  The spoon is pulled out after drilling 5’ and is taken apart to collect the sample, put back down the hole to drill another 5’, and is repeated until desired depth.  This method works best in clay or dry sand.