soil-screening-thumbnail

Detecting VOCs In Soil

Soil analysis for volatile organic compounds VOCs

Back to Industry Guides

VOCs enter soil from many sources including, from the atmosphere by wet or dry deposition (typically rainfall or deposition of ash and particulate smog), as liquids and solids as a result of petrochemical spillage and leakage and clandestine dumping of waste, from deliberate spreading of waste products as an intended improvement to soil health (e.g. sewage sludge, composted domestic waste), and run off of contaminated surface water from asphalted and paved surfaces. Soil biota produce large quantities of methane, but not other VOCs.

Soil Screening For VOCs By Headspace Measurements

Soil analysis for volatile organic compound (VOCs) requires careful sample retrieval handling. For most VOCs, it is often possible and advantageous to analyse a sample headspace.

Soil analysis for VOCs requires careful sample retrieval handling. Gas chromatography Is used to separate sample VOCs from sampled soil. For most VOCs, it is often possible and advantageous to analyse a sample headspace. Screening of a soil samples may be used to determine whether this or a more sensitive technique is deployed in soil analysis. Soil screening by PID exploits the strengths of this technique.

Wherever VOCs are prospective contaminants, soil analysis requires special procedures to prevent VOC loss. Sample collection is undertaken quickly, using awls which are least likely to disturb the soil matrix. Samples are placed in (preferably) glass containers and hermetically sealed promptly. Within 48 hr, soils are treated with methanol or acid to prevent biodegradation of VOCs, and then refrigerated, and even then, for only up to 14 days before analysis.

‘Region 9 Technical Guidelines for Accurately Determining Volatile Organic Compounds (VOC) in Soil and Solid Matrices’, R9QA/05.2, US EPA, 2005.

Analysis Of Volatile Organic Compounds (VOC) In Soil

Soil analysis is undertaken with a view to targeting specific soil variables, which may include a range or very specific VOC contaminants. Initially, a preliminary site investigation – an interrogative survey – is undertaken to establish the likely extent and nature of prospective contamination. On the basis of the preliminary survey, a comprehensive survey is undertaken, involving soil analysis from specified locations.

Soil Screening For VOCs By Headspace Measurements

Many causes of VOC introduction into soil, such as water run-off,headspace-sampling-jar
leakage and dumping are highly localised. This invites the possibility of soil screening during a preliminary site survey, which ensures all known factors are considered in ‘scoping out’ the prospective contamination of a site. From screening data, it is possible to commit to comprehensive analysis of a far greater proportion of samples for which VOC content is high. Although indicative, by identifying locations of high contamination for more comprehensive analysis sampling, soil screening often delivers a much more comprehensive evaluation of soil contamination for a given investigative cost. The cost, portability, robustness, broad sensitivity to VOCs, ease of field use, and rapid and dynamic range of measurement of photoionisation detection (PID) strongly favour it as a means of soil screening. PIS is prescribed in the screening of soil headspace in the US EPA method 3815.

Soil analysis for VOCs requires careful sample retrieval handling. Gas chromatography Is used to separate sample VOCs from sampled soil. For most VOCs, it is often possible and advantageous to analyse a sample headspace. Screening of a soil samples may be used to determine whether this or a more sensitive technique is deployed in soil analysis. Soil screening by PID exploits the strengths of this technique. It is also used to determine areas worthy of more or less intense soil surveyance. The procedures for screening in this ‘exploratory way’ are not widely documented. As with any other VOC in soil analysis, samples of PID headspace screening can and should be handled with a view as to reliable VOC retention in sample containers, reliable VOC partitioning in the sample headspace, and consistent sampling by PID. The use of PID which is resilient to variable water content is to be strongly recommended for soil screening. An example of this would be the MiniPID 2 PPM Gas Sensor.

Download our FREE Guide

“Soil Screening For VOCs By Headspace Measurements”

The soil screening for VOCs by headspace measurement guide which can be downloaded below provides the reader with an in-depth balance of knowledge of Soil analysis which is undertaken with a view to targeting specific soil variables, which may include a range or very specific VOC contaminants. Initially, a preliminary site investigation – an interrogative survey – is undertaken to establish the likely extent and nature of prospective contamination. On the basis of the preliminary survey, a comprehensive survey is undertaken, involving soil analysis from specified locations.

soil-screening-for-vocs-by-headspace-measurements

Related Guides

An Introduction to Field Based Contaminated Land Measurements

The following guide will explain the reasons behind the popularity of PID, despite the challenges presented by field work.

View Details

Benzene Detection – Fixed Instruments

Benzene Detection (Fixed Instruments) - ION Science's Fixed Photoionisation Detectors protect workers and the public from benzene exposure

View Details

Contaminated Land – Why use ION Science PID?

The following guide explains the Tiger XTs humidity resistant design and how it can become an important tool for your sample screening.

View Details

Gas Detection Equipment – Choosing The Right Type

Gas detection for safety is pivotal, so Ion science cuts no corners when it comes to our gas detectors. Explore our variety of gas detectors today!

View Details

Gas Detection Instrument – Do you Require One In Your Industry?

The Gas detection Instrument guide will help you understand the requirement for each type of instrument and which will be best suited to your industry.

View Details

Ground Gas Monitoring – Subsurface Guide

Ground gas monitoring - contaminated ground such as from landfill sites, infilled ground and spilled or leaked petroleum hydrocarbons.

View Details

Risks Associated With Unproven Technology

The following guide provides the reader with knowledge on what to look out for when purchasing a fixed gas detection instrument. Covering key aspects such as performance specification, sensitivity and measurement range, temperature, contamination and humidity tolerance, flexibility and certification.

View Details

Site Investigation and Remediation

When taking out soil investigation, the presence of VOCs which effect soil biota should be considered harmful in respect of their many wider benefits.

View Details

Site Investigation and Remediation

When taking out soil investigation, the presence of VOCs which effect soil biota should be considered harmful in respect of their many wider benefits.

View Details

Soil Remediation With Photoionisation Detection

Soil remediation, which is the reduction of contaminant concentrations within the soil and to reduce contaminants so that they are suitable for use,

View Details

Soil Screening For VOCs By Headspace Measurements

Soil sampling & analysis of VOCs requires careful sample retrieval handling. Most VOCs, it is often possible and advantageous to analyse a sample headspace.

View Details

Subsurface Monitoring – A Guide to Soil/Ground Gas Risk

Subsurface Monitoring is critical and should be considered before any development on top of any soil, As if left uncontrolled can lead to serious effects.

View Details

VOCs In Soil Remediation – A Buyers Guide To Measuring

VOCs in soil remediation can be easily identified with the use of PIDs. They are simple to use and provide quick, accurate results.

View Details

Photoionisation Sensors For The Detection Of Volatile Organic Compounds (VOCs)