Soil Sampling Equipment in Canada: Augers, Core Samplers, and Split Spoons

The quality of a Phase II ESA, geotechnical investigation, or contamination screening program starts with the tool going into the ground. A sand auger used in saturated clay, or a split spoon sampler in a formation requiring intact sample preservation, produces unreliable data regardless of how rigorously the laboratory handles the sample downstream. This guide covers the principal soil sampling equipment used in Canadian environmental and geotechnical practice — sand augers, mud augers, soil core samplers, split spoon samplers — with selection criteria for soil type, investigation depth, and sample integrity requirements, plus decontamination procedures between boreholes.

Types of Soil Samplers: Augers, Core Samplers, and Split Spoons

Soil sampling equipment divides into three functional families: augers (hand-operated or power, for advancing boreholes and recovering disturbed samples), core samplers (for intact, undisturbed samples), and split spoon samplers (for drill-rig-based discrete depth sampling combined with geotechnical SPT testing). Within each family, multiple configurations address different soil conditions.

Sand Augers

A sand auger uses an open-barrel design to retain loose, granular soils during extraction. The cutting head geometry — typically a closed bottom with a helical screw — prevents sand and gravel from falling out of the barrel when you withdraw the tool from the borehole. Sand augers are the correct choice for:

• Unconsolidated granular soils: sands, gravels, sandy loams, and glaciofluvial deposits
• Shallow investigation depths (0–5 m) in the vadose zone
• Exploratory screening where disturbed sample material is acceptable (soil colour, structure, odour logging; PGEM screening)
• Phase II ESA preliminary investigation in fill, alluvial, or aeolian deposits

ERE stocks sand augers in 2″, 3″, and 4″ diameters with 3-foot and 5-foot extension rods in stainless steel and carbon steel. For most Phase II ESA work in Canadian glacial tills and alluvial deposits, a 3″ sand auger with 15 feet of extension rods (5 × 3-foot sections) covers the typical 0–4.5 m investigation depth before drill-rig assistance is needed.

Limitation: Sand augers are not suitable for saturated soils below the water table or for cohesive soils (clays, silts) — material collapses into the barrel or does not retain in the cutting head.

Mud Augers (Clay Augers)

Mud augers — also called Dutch augers, clay augers, or closed-spiral augers — use a closed or bucket-pattern head designed for cohesive, wet soils that would stick in an open-barrel sand auger or collapse back into the borehole. The closed design retains saturated silts, lacustrine clays, soft marine sediments, and high-plasticity soils that an open barrel cannot hold.

Switch from a sand auger to a mud auger when:

• You encounter saturated soil or are working below the seasonal water table
• Soil texture is cohesive — soft clay (Atterberg Liquid Limit > 35%), sensitive marine clay (Leda clay in Eastern Canada), or soft lacustrine silt
• The sand auger is gaining material that falls out during extraction
• Working in fill material with heterogeneous cohesive and granular layers — a mud auger handles both

ERE stocks mud augers in 3″ and 4″ diameters with compatible extension rods that interchange with sand auger sets, allowing field crews to carry one rod set and swap head types.

Soil Core Samplers

When intact soil structure matters — VOC sampling for contamination assessment, geotechnical characterization of undisturbed strength parameters, or contaminant concentration gradient studies — a disturbed auger sample is insufficient. A soil core sampler drives a thin-walled tube into the ground ahead of the borehole and extracts an undisturbed column of soil that preserves stratigraphy, pore structure, and contaminant distribution.

For environmental work, the standard configuration is a stainless steel outer barrel accepting disposable acetate (cellulose acetate butyrate, CAB) or high-density polyethylene (HDPE) liners. Key advantages:

• The disposable liner can be sealed (end caps + parafilm) directly in the field and submitted to the laboratory without transferring the sample — eliminating handling losses and reducing VOC volatilization
• Sequential liners from one core run provide contaminant depth profiles at high vertical resolution
• Stainless steel contact surfaces are chemically inert to petroleum hydrocarbons, chlorinated solvents, and metals

ERE carries core samplers compatible with standard 1.5″ and 2″ liner diameters, with drive heads for hand-driving (shallow work) and slide-hammer attachments for harder formations. For VOC-sensitive samples, protocol requires: seal the liner within 2 minutes of extraction, minimize temperature exposure, and ship on ice with 48-hour hold time to laboratory.

Split Spoon Samplers

The split spoon sampler (standard outer diameter 2″, inner diameter 1.375″) is the ASTM D1586 Standard Test Method device used during hollow-stem auger or rotary drilling. It is the most widely used soil sampling method for Phase II ESA work at depth in Canada — it yields both a soil sample for analytical testing and Standard Penetration Test (SPT) N-values for geotechnical characterization.

The split spoon is driven into undisturbed soil at the base of the borehole by a 140-lb (63.5 kg) hammer dropped 30 inches (762 mm). The SPT N-value (blows per 300 mm of penetration) characterizes soil consistency and provides input for bearing capacity and settlement calculations. For Phase II ESA, the split spoon sample at each sampling interval is extruded from the spoon, logged for stratigraphy and field indicators (odour, staining, sheen), and subsampled for laboratory analysis.

ERE stocks split spoon samplers, drive shoes, and split barrel replacements for 2″ standard and 2.5″ modified samplers. For large-diameter continuous sampling (Shelby tubes, piston samplers for soft sensitive clays), contact ERE directly for availability.

Applications by Investigation Type

Sampler selection also follows the investigation phase and regulatory context. Each phase has defined sampling objectives, depth requirements, and data quality objectives (DQOs) that drive equipment selection.

Selecting the Right Sampler: A Field Decision Framework

In practice, a field crew advances a borehole through multiple soil conditions in a single day. Selection is not static — it shifts with depth and formation changes. Here is the field decision logic:

Step 1: Identify Soil Type at Target Depth

Check site geology from Phase I background research and borehole logs from adjacent investigations. Granular (sand, gravel, coarse-grained fill) → sand auger. Cohesive or saturated (silt, clay, soft organic) → mud auger. Below water table in any soil → mud auger for borehole advancement, but consider whether you need a core sampler for the sample interval.

Step 2: Determine Sample Integrity Requirement

Are you screening (disturbed sample adequate for PGEM, colour, odour, stratigraphy logging) or are you collecting a sample for laboratory analysis that will be the basis of a risk assessment? For regulatory submissions under Ontario's RSC Regulation 153/04, BC's CSR, or Alberta's ESRD Tier 1/2 guidelines, VOC concentrations in soil samples must be collected with methods that minimize volatilization. A disturbed auger sample placed loose in a jar will underreport benzene, toluene, and chlorinated solvent concentrations by 30–80% relative to a sealed core liner. If the data will be used for risk assessment decisions, use a core sampler with a sealed liner.

Step 3: Confirm Depth and Access

Hand augers (sand or mud) are practical to approximately 4.5–6 m (15–20 feet) in most unconsolidated soils. Below that depth, borehole caving, advancing torque, and rod deflection make manual advancement impractical. At depths below 3–4 m in competent formation, a drill rig with hollow-stem augers or rotary drilling is standard practice. Split spoon sampling is the default discrete-interval method once a drill rig is on site.

Decontamination Between Boreholes

Decontamination of soil sampling equipment between sample intervals and between boreholes is a QA/QC requirement under CCME and provincial ESA protocols, not an optional best practice. Failure to decontaminate introduces cross-contamination — moving soil or porewater from a contaminated zone into a clean zone, or carrying contamination from a highly impacted borehole to a background borehole used as a reference point.

Standard Decontamination Sequence

The CCME Protocol for the Decontamination of Field Equipment (CCME 1993, still referenced in current provincial guidance) specifies a three-step approach for soil sampling equipment:

1. Dry decontamination: Remove all visible soil from the sampler using a brush or clean rag. Discard the rag. Do not cross-use rags between contaminated and clean zones.
2. Detergent wash: Wash all equipment surfaces (barrel, drive shoe, rods, connections) with a phosphate-free laboratory-grade detergent and tap water or distilled water. Use a long-handled brush to access the interior of the core barrel or split spoon barrel. Rinse with clean water.
3. Solvent rinse (when organic contamination is suspected): Rinse with isopropanol (IPA) or methanol and allow to air-dry. Use only analytical-grade solvents in a ventilated area. This step is required for samplers that have contacted soil with confirmed or suspected petroleum hydrocarbons, chlorinated solvents, or other organic contaminants.

For high-contamination boreholes (free-phase NAPL observed, strong odour, visible staining in soil), consider using dedicated equipment for that borehole that is bagged and removed from the site separately — the decontamination step cannot reliably remove all free-phase contamination from thread connections and internal surfaces.

Use of Disposable Components

Where feasible, using disposable components eliminates the decontamination burden entirely:

• Disposable acetate or HDPE liners in core samplers — seal after each run, insert new liner for the next interval
• Disposable PVC bailers for groundwater grab sampling (see the environmental sampling equipment guide for bailer selection)
• Disposable nitrile gloves changed between boreholes (hands as a vector for cross-contamination are often underestimated)

ERE's Soil Sampling Line

ERE supplies the full range of soil sampling equipment used in Canadian Phase II ESA, geotechnical, and remediation investigations. Our inventory covers:

• Sand augers — 2″, 3″, and 4″, stainless steel and carbon steel, with interchangeable extension rods (3-foot and 5-foot sections)
• Mud augers (clay augers) — 3″ and 4″, compatible rod threads to interchange with sand auger sets
• Soil core samplers — stainless steel outer barrel accepting 1.5″ and 2″ acetate or HDPE disposable liners; drive heads for hand-driving and slide-hammer
• Split spoon samplers — standard 2″ OD, ASTM D1586-compliant, with replacement drive shoes and inner liner options
• Extension rods — stainless steel and carbon steel, 3-foot and 5-foot sections, with T-handle and slide-hammer fittings
• Accessories — decontamination brushes, acetate and HDPE liners, end caps, parafilm, sample jars and labels

All equipment is available for purchase or rental. Browse the full soil sampling collection or contact ERE for project-specific equipment kits.

Frequently Asked Questions

What is the difference between a sand auger and a mud auger?

A sand auger uses an open-barrel design with a cutting head that retains granular, loose soils (sand, gravel) during extraction. A mud auger (clay auger) uses a closed or Dutch-pattern bucket head that retains cohesive, wet soils (silt, clay, soft organic) that would fall out of an open barrel. The choice depends entirely on the soil type at your investigation depth. In mixed-profile investigations, crews carry both and swap heads as conditions change — ERE's auger sets share rod threads, so head changes take under a minute in the field.

When does a Phase II ESA require an intact (undisturbed) soil sample?

Intact samples are required whenever the analytical result will be used in a risk assessment calculation or regulatory submission where volatile losses from sample handling would materially affect the concentration reported. Under Ontario's Regulation 153/04 (RSC), BC's Contaminated Sites Regulation, and Alberta's AER Tier 1/2 guidelines, soil samples collected for VOC analysis (petroleum hydrocarbons — PHC fractionation, BTEX, chlorinated solvents) must be collected with methods that minimize volatilization. The standard method is a sealed disposable liner extracted from a core sampler and capped within 2 minutes of extraction. Disturbed auger samples significantly underreport volatile compound concentrations.

How deep can a hand auger realistically go on a Phase II ESA?

In most unconsolidated Canadian soils, hand augers are practical to approximately 4–6 m (13–20 feet) with extension rods. The practical limit is determined by torque (clay-rich soils become very difficult to turn beyond 3–4 m), borehole caving (granular soils below the water table cave into the borehole before you can advance the next rod section), and deflection (rods begin to bow and bind beyond 4–5 m). Below these depths, or in any formation requiring SPT data for geotechnical characterization, a drill rig with hollow-stem auger or rotary capability is the appropriate tool.

Is decontamination between sample intervals within the same borehole required?

Yes, for split spoon samplers in a Phase II ESA when the sampling purpose is to characterize contamination at distinct depth intervals. If you do not decontaminate the split spoon between the 1.5 m sample and the 3.0 m sample, and the 1.5 m soil is contaminated while the 3.0 m soil is not, the 3.0 m result will be affected by carry-over from the first sample. CCME and provincial protocols require decontamination between sample intervals when the investigation objective is vertical delineation. Dry-brush decontamination between intervals in the same borehole is the minimum; full wash is required between boreholes.

Related articles

• Environmental Sampling Equipment Guide for Canada

Lire en français : Équipement d'échantillonnage des sols au Canada