What Is Soil?
Soil analysis serves two different purposes. CONTAMINATION ANALYSIS determines the presence and level of pollutants such as heavy metals, petroleum hydrocarbons, PAHs, PCBs and pesticides at a site. FERTILITY ANALYSIS measures organic matter, pH, salinity and nutrients for agricultural purposes. The sampling strategy is entirely different depending on the purpose.
Purpose of Soil
The purpose is risk determination in contaminated-site assessments, showing suitability for a land-use change, or establishing a fertilisation plan in agricultural production.
Which Products Is Soil Applied To?
- Industrial site soils
- Contaminated-site investigation specimens
- Agricultural land
- Excavated and fill materials
- Vicinity of a landfill
In Which Sectors Is Soil Used?
Standards Related to Soil
- TS EN ISO 18400 series (soil sampling)
- TS EN 16179 (sample pretreatment)
- TS EN ISO 11466 / EN 13657 (digestion with aqua regia)
- TS EN ISO 18287 (PAH — GC-MS)
- TS EN ISO 16703 (mineral oil content — GC-FID)
- TS EN ISO 10390 (pH), TS EN ISO 11265 (electrical conductivity)
Soil Conditions
- Sampling strategy
- Per purpose; grid or targeted for contamination investigation, composite for fertility
- Depth
- Specimen depth is recorded; surface and deep specimens are assessed separately
- Volatile compounds
- If a volatile pollutant is being tested for, the specimen is taken in a separate, headspace-free container
- Preparation
- Drying and sieving steps per the standard; drying is not done for some parameters
Equipment for Soil
- Soil drilling and sampling equipment
- ICP-MS / ICP-OES and microwave digestion
- GC-MS and GC-FID
- pH meter and conductivity meter
- Grinder, sieve set and oven
Sample Requirements for Soil
- Sampling is the largest component of total uncertainty in environmental analysis. The specimen container, preservation (acidification, cooling, storage in the dark), fill method and time to reach the laboratory are all defined in the standard; if any one is not met, the result loses its validity. Sampling must be carried out by authorised personnel per a written plan.
- Specimen point coordinates and depth must be recorded
- A separate, headspace-free specimen is required for volatile pollutants
- A composite specimen should be used only where appropriate — it masks point-specific information in a contamination investigation
Duration of Soil
Sample preparation (drying, grinding, sieving) takes the first day of the analysis. Metal analyses take several working days; organic pollutant screens take longer due to extraction and clean-up.
Soil Procedure
- 1The purpose is determined and the sampling plan prepared.
- 2Specimens are taken from the planned points and depths.
- 3Separate specimens are taken for volatile parameters.
- 4The specimen is prepared in the laboratory (drying, grinding, sieving).
- 5Digestion or extraction suited to the parameter is performed.
- 6Instrumental measurement is performed and results assessed.
Soil Acceptance Criteria
In contamination assessment, the acceptance criterion is the target and intervention values defined per land use; these are set in national legislation and differ for residential, commercial or industrial use. In agricultural fertility analysis there is no fixed limit; the result is converted into a fertilisation recommendation.
Evaluation of Results
Composite sampling is misleading in contamination investigation: a highly contaminated point is diluted and missed when mixed with clean points. A point specimen is the correct approach in contamination investigation, and a composite specimen in fertility analysis.
Soil Report
- Specimen points, coordinates and depths
- Sampling strategy and its justification
- Sample preparation steps
- Method, result and limit of quantification for each parameter
- Target/intervention values compared against
Accreditation
EUROLAB holds internationally recognised accreditation obtained from accreditation bodies party to the IAF and ILAC multilateral recognition arrangements, under ISO/IEC 17025 for laboratory testing, ISO/IEC 17020 for inspection and surveillance, and ISO/IEC 17021-1 and ISO/IEC 17065 for system and product certification. This chain ensures the reports and certificates issued are accepted worldwide.
Whether this test can be offered within accredited scope depends on your product and the standard applied; since accreditation is method-based, the scope is confirmed in writing at the quotation stage.
Scope and authorisationsRelated Regulations
- 2004/35/EC Environmental Liability Directive
- 2008/98/EC Waste Framework Directive
- (EU) 2010/75 Industrial Emissions Directive
Environmental Analysis — What Does This Testing Field Cover?
The section below describes the field that the Soil test belongs to; the conditions and acceptance criteria of this particular test are given in the sections above. The scope specific to your product is confirmed in writing at the quotation stage.
Environmental analysis determines the presence and concentration of pollutants in water, soil, waste, air and flue gas samples. The output of this family is usually part of a permit, a declaration or an inspection file; the result has direct legal consequences.
In this family SAMPLING is half the result, and this is the feature that most sets the field apart. A sample taken at the wrong time, in the wrong container, under the wrong preservation or from the wrong point gives an invalid result no matter how well it is analysed in the laboratory. In waste water a grab sample and a composite sample give different information; in soil, surface and depth produce different results. Sampling therefore has its own standards and its own accreditation scope.
On the water side, physico-chemical parameters (pH, conductivity, turbidity, COD, BOD, suspended solids), ions, heavy metals, organic pollutants and microbiological parameters are measured. Drinking water and waste water carry different parameter sets and different limits; the same laboratory method leads to a different decision under the two regimes.
In soil and waste, heavy metals, hydrocarbons, PAH and PCB compounds and LEACHING BEHAVIOUR are determined. The leaching test carries a logic peculiar to this field: it is not the total amount of a pollutant in soil but the fraction that can pass into water that determines the environmental risk. Waste classification and the disposal decision rest largely on this test.
On the emissions side, dust, sulphur dioxide, nitrogen oxides, carbon monoxide, oxygen, moisture and total organic carbon are monitored in flue gas. Measurement is made on site under operating conditions and must represent the plant's actual operating regime; a measurement taken at low load does not show the emissions at full capacity.
Continuous measurement systems are a separate body of work. In large plants emissions are monitored continuously and the accuracy of these systems is verified periodically by comparison with independent measurements; the quality assurance framework governs this.
Noise and vibration measurements complete the environmental impact side of the field: environmental noise mapping, workplace noise exposure and vibration exposure measurements produce evidence for both environmental and occupational health legislation.
Method groups in this field
Sampling
Separate sampling standards for water, waste water, soil, waste, flue gas and ambient air; grab, composite and continuous sampling techniques.
Water physico-chemical
pH, conductivity, turbidity, colour, suspended solids, COD, BOD, TOC, alkalinity, nitrogen and phosphorus species.
Elemental analysis
Determination of heavy metals and trace elements in water, soil and waste by ICP-OES and ICP-MS.
Organic pollutants
Volatile organic compounds, PAH, PCB and organochlorine pesticides by GC-MS; hydrocarbon oil index.
Flue gas
Measurement of dust, SO2, NOx, CO, O2, moisture and total gaseous organic carbon; quality assurance of automated measuring systems.
Leaching and waste characterisation
Leaching tests and waste classification parameters; the basis for the disposal decision.
Commonly confused in this field
- An analytical result cannot be used on its own without the sampling record; the time, point, conditions and chain of custody are part of the report.
- Total content and leachable amount give different information; in waste classification, leaching behaviour is what counts.
- Emission measurement must be made under representative operating conditions of the plant; a result taken at partial load is misleading.
- Drinking water and waste water limits are defined in different legislation; the same parameter carries a different threshold under the two regimes.
- A sample from a single point does not represent the whole area; assessment of a contaminated site requires a grid-based sampling plan.
Which decisions these results support
- Compliance with environmental permits and discharge limits
- Quality assurance of continuous emission measurement systems
- Contaminated site assessment and the remediation decision
- Waste classification and selection of the disposal method
- Workplace exposure measurements and occupational health obligations
Related Tests
Frequently Asked Questions About Soil
How many points should I sample?
Site size, past activities and the purpose of the investigation determine this. The ISO 18400 series defines different strategies: grid sampling for a preliminary investigation, targeted sampling for a known pollution source.
Does a fertility analysis give information about contamination?
No. Fertility analysis looks at pH, organic matter and nutrients; it does not show heavy metal or hydrocarbon contamination. The two analyses use different parameter sets.