1. SOIL SAMPLING
SOIL & SEDIMENT SAMPLING
Yong Soon Kong (Assoc. Prof. Dr.)
Faculty of Applied Sciences
Universiti Teknologi MARA
2. TABLE OF CONTENT
3.1 Basic Principles of Soil Sampling
3.2 Site selection
3.3 Selection of sampling approach
3.4 Selection of area, sampling point, and parameters for sampling
3.5 Selection of sampling equipment
3.6 Guidelines for handling and storage of soil sample
3.7 Pretreatment and extraction technique for contaminants in soil
4. VARIOUS OBJECTIVES OF SOIL MONITORING
• Detecting monitoring - the main objective of the monitoring project
to detect the presence or absence of a given contaminant.
• Assessment monitoring - the main objective of the plan is to
determine the extent of known contamination.
• Performance monitoring - the objective of the plan to evaluate the
feasibility and required financial burden for the remediation of a pre-
• Research monitoring - the monitoring process to be a part of a follow-
up plan to evaluate the success of remediation efforts.
5. PARTS OF MONITORING PLAN
An integrated monitoring plan comprises generally of the following
1. Site characterisation
2. Data acquisition
3. Data quality control
6. SITE CHARACTERIZATION
• Information about the investigated site (i.e., geological, pedological,
hydrogeological, and historical data about land use) should be analysed.
• Geomorphic and pedological characteristics of the area from the following
types of maps should be obtained:
• Base map
• Geologic map
• Hydrologic map
• Overburden map
• Class activity: form four groups and present the characteristics of all maps
• See Soil Sampling Strategies , Using the Web Soil Survey Tool video
8. FACTORS THAT AFFECTS RELIABILITY OF SAMPLES
• The reliability of samples, as representatives for the environmental
conditions in the investigated area, depends principally on:
• frequency of sampling,
• technical procedures of sample collection,
• technical errors of the operator,
• treatment of samples in the course of their collection,
• transport to the laboratory.
9. Fundamental Sampling Error
The source of most sampling errors
Due to the fact that not all particles have the
Cannot be eliminated, but can be estimated
Results in variability and a lack of precision
Particle size, sample mass, and degree of
heterogeneity are important factors
10. Grouping and Segregation Error
Due to the fact that not all particles are
size, shape, concentration
Can be reduced
collection of multiple increments
11. How Many Samples?
There is no “cookbook” approach
Consider an iterative approach
Need to take into account
Degree of accuracy
Variability of constituents
Pitard (1993); Runnells et al. (1997); USEPA (2002); Price (2009)
Pitard “rule of thumb” that a
sample should be made up of at
least 30 increments
12. Need to Collect more Sample Mass when
Excessive sample size or amount should be avoided for
financial/logistic consideration (i.e., storage, transportation,
13. Sampling for Soil Horizon
Smith, D.B., Solano, Federico, Woodruff, L.G., Cannon, W.F., and Ellefsen, K.J., 2019,
Geochemical and mineralogical maps, with interpretation, for soils of the conterminous United
States: U.S. Geological Survey Scientific Investigations Report 2017-
5118, https://doi.org/10.3133/sir20175118. [https://pubs.usgs.gov/sir/2017/5118/]
14. Sampling Strategy for Mine Piles
1. Divide pile into at least 30 cells of roughly
equal surface area and randomly collect a
surficial sample from each cell
2. Combine cell samples into a mine-pile
3. Dry sieve the mine-pile composite sample to
4. Final composite sample should weigh at least
1 kg after sieving
15. Sampling Strategy for Mine Piles, cont.
sample collected using
this sampling strategy
contains as much
to average value, as
30 individual grab
samples at 1/30 of the
Smith et al. (2000, 2002, 2003, 2006, 2007)
1 composite sample is
analyzed instead of
30 grab samples
16. Soil Sample Amount
• Depends of the number of physicochemical characterization. A
minimum of approximately 200 g of soil is needed for each
• A dry mass of approximately 5–100 g is needed for contaminant
• More soil samples are needed if contaminants are not accumulated in
the soils, and vice versa.
• 15 L is required for bioaccumulation tests (based on an average of 3 L
sediment per test chamber and 5 replicates), and 8–16 L sediment is
needed to conduct benthic macro-intevertebrate assessments (EPA,
18. LOCATION OF SAMPLE POINTS
• Spatial patterns of sampling:
• the simple rectilinear grid type:
• Systematic grid pattern
• Random block pattern
• the traverse type
• Open traverse
• Closed traverse
22. Whole Field Area = ~150 acres
Figure 6. Initially sampled on a 2.5 acre grid (area composite
sample), similar adjacent grid units have been combined for re-
sampling. The number of samples has been reduced from 56 to
33. Re-sampling “grid size” now ranges from 2.5 to 15 acres
25. TOOL FOR SAMPLING SOIL - AUGER
• Depths of soil sampling points as
recommended by the UN/ECE ICP Forests
programme (UN/ECE ICP Forests 1994):
0–5 cm, 5–10 cm, 10–20 cm, and 40–80
• Soil augers is used for sampling depths
from 1 to 2 metres.
26. • Use a trowel or sampling
tube to collect soil samples.
TOOL FOR SAMPLING SOIL - TUBE
27. CLASS ACTIVITY
Form five groups and present the characteristics of:
i. light power augers,
ii. box-type samplers,
iii. Hillier peat borer,
iv. Russian peat borer,
v. piston sampler.
28. THE DIFFERENT ZONES OF GROUNDWATER
• the vadose zone also known as the aerated
zone or the unsaturated zone is that column
reaching down to the water table. It may be
• At the base of the vadose zone there is a
region where the water rising by capillary
pressure from the water table forms a fringe,
the height of which depends on the pore sizes
of the sediments.
• The capillary fringe forms a transition zone
between the permanently saturated phreatic
zone and the vadose zone.
• The water table (the upper layer of the saturated
zone) forms the base of the capillary fringe.
30. • Centrifuge drainage
• Saturation extract method
• water is added to change the
concentration of some anions.
• The original concentrations can be
recalculated if the water content of the
soil sample and the amount of water
added is known.
SAMPLING SOIL SOLUTION
33. SAMPLING SOIL AIR
• Simple method: air extraction from holes bored with an auger using a
manual suction pump, the collected samples should be stored in
airtight stainless steel or glass containers before being sent to the
• Advanced methods: soil air is sucked through a probe, rammed in the
soil to a depth of about 1m, by pumps mounted on a vehicle
equipped with proper analytical facilities.
• Passive sampling: uses an activated charcoal rod buried in the soil as
an in situ adsorbent for VOCs. After a few days or weeks the charcoal
rod is retrieved and analysed by gas chromatography or any other
suitable analytical method.
34. Equipment for Sediment Sampling
• Common sampling tools used
1. Ekman dredge
2. Petersen dredge
3. Ponar dredge
4. Sediment core sampler
36. Preservation for Soil Samples
• Soils are usually air-dried after sampling. However, if soils or
sediments are anaerobic, it should not be exposed to air.
• Chemical preservatives are usually not needed for soil samples.
• This is the only common chemical preservation method for soil
samples is the addition of methanol or sodium bisulfate for VOC
analysis (Popek, 2003).
• Wide-mouth containers are used for soil samples.
37. SOIL PRESERVATION FOR VOC ANALYSIS
• Samples are preserved in methanol for “high level” analysis
– Calibration range increases to 200 μg/kg with only a 5 gram sample.
• Samples are preserved in sodium bisulfate for “low level” analysis
– Method Detection Limits down to 0.5 μg/Kg and concentrations < 200 μg/Kg
• Field preservation is typically done at a 1:1 ratio (weight/volume) of soil and
• Pre-preserved vials supplied by the laboratory are weighed to allow calculation of soil
sample weight – careful not to add additional label!
• Soil samples are based on volume and weigh approximately 5, 10, or 25 grams based
on sample type
• Hold time for samples is 14 days when chilled @ 4 oC
38. Collecting Samples for Field Preservation with Methanol
• Using a Terra Core sampler, place a 5
gram plug of soil into pre-preserved
vial containing methanol
• 1:1 or greater weight/volume ratio of
soil to methanol
• Operation must be done quickly to
prevent VOC loss
• Tared weight of methanol vials should
be verified before samples are
• Methanol is a toxic and
• It must be handled with all
required safety precautions
related to toxic and
• Methanol must be handled
in a ventilated area.
• Use protective gloves
when handling the
• Store methanol away from
sources of ignition such as
extreme heat or open
39. Collecting Samples for Field Preservation
with Sodium Bisulfate
• Using a Terra Core sampler, place 5 gram plug of soil into pre-preserved
vial containing 20% sodium bisulfate aqueous solution
• Calcareous soil types should be checked for effervescence prior to
sampling or vial may explode!
• 1:1 or greater weight/volume soil/preservative ratio
• Two vials are collected (plus a MeOH preserved vial)
• Collect an additional 3 vials for an MS/MSD
• Tared weight of pre-preserved vials should be verified before samples are
40. PROCEDURAL PRECAUTIONS - CHAIN OF
• Samples shall be custody sealed during long-term storage or shipment.
• Collected samples are in the custody of the sampler or sample custodian
until the samples are relinquished to another party.
• If samples are transported by the sampler, they will remain under his/her
custody or be secured until they are relinquished.
• Documentation of field sampling is done in a bound logbook.
• Chain-of-custody documents shall be filled out and remain with the
samples until custody is relinquished.
• All shipping documents, such as air bills, bills of lading, etc., shall be
retained by the project leader in the project files.