Article Contaminated Land

Supporting the contaminated land community

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Tags: contamination data FASA MCERTS

Dealing with uncertainty and heterogeneity in the risk-based land management process continues to present challenges for the contaminated land community.  The up front investment required to more accurately define risk is sometimes difficult to communicate to all stakeholders involved in projects which can, in some instances, lead to regretful compromises.

 

The EA’s MCerts Policy has increased confidence

Application of the Environment Agency’s MCerts Policy, which standardised laboratory based analytical procedures, has delivered increased confidence in the outputs of samples analysed by laboratories, however the relative cost per sample continues to offer opposition to increasing sampling density. This challenge is recognised by many, including the Environment Agency, however, there is a growing body of evidence to support the conclusion that greater emphasis needs to be placed upon overcoming it if we are to continue to develop potentially contaminated sites whilst eliminating risk and future liabilities

 

Added value…

Portable field analytical tools are, therefore, being increasingly considered to have an important role in supporting the community overcome this challenge. Their appropriate application can offer many added-value and commercial benefits. These include:

 

  • more rapid and cost effective determination of spatial and temporal variations (i.e. heterogeneity);
  • the optimisation of sampling strategies for subsequent laboratory analysis which, ultimately, increase the quality of site data and confidence; and
  • in the right circumstances, they can even enable on-site decision making, thereby dramatically saving time and money.

 

Such tools have been available for several decades and have been rigorously applied in other environmental fields, such as the trade effluent and stack emission monitoring.  However, their application in the contaminated land sector has been relatively low to date. There are many rational reasons for this, including a lack of awareness and confidence in their application, due, in part, to a lack of case history providing technical and economic evidence; a lack of available skills within the practitioner community; and a limited level of acceptance in their application and interpretation throughout the community.

 

FASA workshop

To this end, FASA, the Field Analytical Suppliers Association, hosted x4, one-day workshops this year, to provide attendees with a practical introduction to field analytical tools.

 

These events included:

  • the provision of information related to how they fit within the UK regulatory framework, kindly provided by Bob Barnes and Brian Bone from the Environment Agency;
  • an overview of available tools and case study information detailing the application of five of the most commonly applied; and
  • attendees were provided with the opportunity to see the tools for themselves and gain answers to their individual needs during afternoon demonstration surgeries.

 

What is FASA?

FASA is an independent body created to support the efforts of regulators, industry and laboratories in the management of potentially contaminated environments. It is funded and coordinated by suppliers and manufacturers of field tools in the UK and is supported and administered by IPM-Net.

The workshops described form part of its commitment to assist the community gain an informed understanding of the application of field analytical tools and their appropriate use. FASA aims to further assist the community by working with key stakeholders to develop guidelines, training material, best practice QC/QA procedures as well as technique specific information, such as case studies and evaluations.

 

Following analysis of the attendees’ feedback from the workshops it is clear that such information will assist the community, with 81% and 77% stating that the lack of available guidance and performance information, respectively, were barriers to their uptake. Their perceived costs, a lack of regulation and a lack of information on how to use field tools were, individually, seen as barriers to 60% of attendees.

 

New guidance being developed

The Environment Agency is currently developing guidance on the use of field analytical tools within the risk-based approach to land contamination. This document will discuss, amongst other aspects, the application of field tools in the context of sampling and analytical plans, fit for purpose decision making, building lines of evidence and informing conceptual site models. The first draft is likely to be circulated to the FASA committee by the end of this year, with further release anticipated to occur in the Spring of 2007.

 

For further information contact:

 

Mr Perry Guess , FASA Chairman

Tel:               01865 610504

E-mail:          perry.guess@earth.ox.ac.uk

 

FASA representatives will give a presentation at the next Contaminated Land WG (20 February 2007) on the use of field analytical tools.

Article Contaminated Land Laboratories

Testing times for soils

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Tags: chemical contaminated MCERTS soils

The Environment Agency has issued a revised version of its MCERTS policy for the chemical testing of soils. The Agency established its Monitoring Certification Scheme (MCERTS) to ensure high standards of environmental monitoring, and in 2003 it extended the scheme to include soils testing. The Agency’s policy is that the MCERTS standard should apply to all chemical testing of soil where the results are submitted to the Agency for regulatory purposes.

This latest version of the policy clarifies the Agency’s position on in situ testing. The Agency believes that in situ testing has a valuable complementary role to play in improving the quality of site investigation and remediation as well as reducing costs. Appropriate on site testing can be used for improved targeting of conventional sampling, better spatial delineation of contaminated areas, and the development of conceptual site models.

The document has been published on the Land Contamination section of the Agency’s web site at:

http://www.environment-agency.gov.uk/subjects/landquality/113813/590825/?version=1&lang=_e

Article Contaminated Land Laboratories

The problem of made ground

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Tags: analysis brownfield sites Environment Agency Geoscientists laboratory MCERTS soil

The categorisation, analysis and reporting of ‘made ground’ is a recurring nightmare for the modern laboratory. Traditionally a by-product of land reclamation schemes, a container of the stuff can contain traces of anything from steel, concrete and brick to nappies and Coke cans – and that’s on a good day.

Ask anyone from the engineer taking samples at the coalface to the men in white coats analysing them, and you will find that there is no all-encompassing approach to deal with the ‘made ground’ conundrum. Nevertheless, with brownfield sites being universally hailed as the sustainable way forward, now, more than ever before, is the time to seriously evaluate the methods employed both on-site and in the laboratory and try to circumvent the insidious ‘no easy answer’ maxim.

Much of the confusion goes back to the introduction of the Environment Agency’s Monitoring Certification Scheme (MCERTS) for the chemical testing of soils. Any laboratory operating under this banner has to submit results that fulfil both the general requirements of ISO/IEC 17025 and the specific method validation and performance requirements of MCERTS. The latter is problematic for laboratories dealing with made ground, inasmuch as it requires samples to conform to specific sample matrices in order for the results to become accredited. For relatively unadulterated soils, this has meant the creation of soil classification categories such as ‘loamy soil’, ‘sandy soil’ or ‘clay type soil’. It is worth noting that while some geotechnical engineers may see this as a tenuous oversimplification, it is widely regarded as the best available approach and has the full endorsement of the Environment Agency and UKAS – albeit based on economical drivers. Made ground’s inherent ambiguity throws a rather obtrusive spanner in the works when faced with these basic matrices and prompts all manner of interpretive stances and questions. Some good starters for ten: can you report made ground results as accredited? Is it possible to report them as ‘unaccredited’ to make it clear to the engineer that the sample does not fall into a clear defined matrix?

It isn’t just an issue of categorisation – the whole process, from preparation to final report, is divested of any consistency as laboratories adopt their own approach by asking questions such as do we dry the sample? Do we mill the sample to uniform particle size? Do we discard anything over 2mm? Do we ignore everything that is not soil? None of these methods will provide an inaccurate result per se, but each has the potential to give a misleading picture of the site.

If, in addition to that head-scratching list of questions, you consider the fact that the commercially driven nature of redevelopment schemes has turned laboratories into high-tech, scientific conveyor belts, the complexities of the problem becomes increasingly pronounced. It is a crossroads situation reliant on good judgement, experience and, above all, a decent sample. It is impossible to overstate the critical nature of the latter point: without a comprehensive sample, the laboratory cannot do its job. In other words, it cannot capture the essence of a site’s industrial legacy and act as a signpost to the appropriate action.

Though MCERTS has to a certain extent raised the standards in the laboratory, it missed an opportunity by not offering any guidance to the geotechnical engineer on the best available techniques (BAT) for sampling, storage and transportation; nor does it elaborate on the consequences of incorrect, inappropriate or inadequate sampling. The reason the EA has put the onus on the laboratories is understandable – to allow continuity of testing pre- and post-MCERTS – but the resultant confusion and knowledge deficit, particularly with regards to sampling, is less than satisfactory.

As throwing legislation at the problem is unlikely to be constructive, the best achievable course of action is to engender a milieu of interdisciplinary compatibility fuelled by open lines of communication, intellectual communality and the symbiotic sharing of knowledge. Geoscientists should learn how to adequately describe their sample, how to make the sample manageable for the laboratory and to understand the laboratory machinations of sample preparation, analysis and reporting. By the same token, chemists should acquire some field experience, learn about the conditions engineers face on-site and educate themselves on the processes that inform geotechnical sampling techniques.

If the question of how to produce consistently accurate results from made ground is reducible to a single answer, it can only be to ask more questions: what are the limitations of the selected analytical method? If there are limitations, do they matter in this case? On what basis is the data reported? Does it match the basis on which my acceptance criteria are calculated? Has the sample data been generated in ideal conditions using ideal standards which are unlikely to represent the conditions on my site? Add a soupçon of communication, wait for MCERTS to catch up and we’re well on our way.

Andrew Buck PhD, MSc, CSci, CChem, FRSC is the Technical Director of Envirolab (www.envlab.co.uk)

Article Contaminated Land Laboratories

MCERTS

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Tags: Environment Agency laboratory MCERTS soil testing

The Environment Agency’s Monitoring Certification Scheme for the Chemical Testing of Soils:
What it is. How it affects you. What you need to do.

MCERTS Monitoring Certification Schemes were first introduced in industrial sectors with regulated processes that resulted in stack emissions. The scheme requires those companies to deliver monitoring results that are “valid, reliable and accurate”. To get to this position depends on using the appropriate resources – correct test methods, competent personal, accredited organisations and suitable equipment and planning.

The MCERTS scheme for chemical testing of soils was introduced by the Environment Agency to support their regulatory activities and make informed, quality assessments on the management of contaminated land under a number of regimes, including, Part IIa of the Environmental Protection Act 1990, Pollution Prevention and Control Regulations 2000 and the Waste Management Licensing Regulations 1994.

The scheme is applicable to all testing laboratories and procurers of analytical services, where results generated for the chemical testing of soil are submitted to the Agency. In order to gain accreditation on the scheme, laboratories are required to have their processes, essentially test methods, in a quality management framework, by both the United Kingdom Accreditation Service (UKAS) to the international standard ISO 17025 and also MCERTS requirements.

There are increasing pressures on businesses to comply with Environment Agency regulations and European and international standards. Using a laboratory with MCERTS accreditation alleviates some of this pressure because it guarantees the proper use of suitable methods, standards, services and equipment, trained and qualified personnel, quality assurance and quality control all leading to reliable data. MCERTS accreditation also assures users that the laboratory meets performance standards set out in current international standards and the growing requirements of EC directives.

Failure to meet the regulations can be costly, both financially and to a company’s reputation. An MCERTS accredited laboratory assures the user that they have met standards in a number of areas including:

  • The selection and validation of test methods

  • Sampling pre-treatment and preparation

  • The estimation of measurement uncertainty

  • Participation in proficiency testing schemes

  • The reporting of results and information

The benefits of the scheme include:

  • Providing assurance to stakeholders of the quality of data from testing

  • A level playing field, based on the Agency’s requirements, is established

  • Identifying that the chemical testing of soil is a critical component in producing defensible data for regulatory purposes.

In order to guarantee reliable data from the chemical testing of soils and therefore reassurance that risks are minimised, procurers of testing should:

  • Ensure the chemical analysis results submitted to the Agency for regulatory purposes conform to MCERTS requirements.

  • Check that the laboratory conducting the testing has MCERTS accreditation for all the parameters requiring analysis. Accreditation is given on a parameter-by-parameter basis. If they do not have the correct accreditation sub-contracting of the test required to another MCERTS laboratory may be required. If a suitable laboratory does not appear to be available, contact the Environment Agency for advice.

  • Check that the test methods employed by the laboratory are appropriate and fit for purpose in terms of the parameter, the Critical level of interest (CLI) and the matrix. The CLI may be a soil guideline value or a regulatory limit.

  • Check with the laboratory that the sampling processes, preservation and transportation are appropriate.

  • In collaboration with your chosen laboratory, have complete audit trails available that address aspects such as sample location, depth of sample, date and time of sample, reference identity and the laboratory used.

The MCERTS scheme for the chemical testing of soils was phased in, but has been fully operational since 1 March 2005. Therefore, all data for regulatory purposes should now be to the MCERTS standard. Laboratories and the procurers of testing need to work together to ensure that the test data provided meets the requirements and satisfies the needs of the ultimate client.

Cliff Billings Group Technical & Quality Manager STL UK

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EA’s position on MCERTs

From 1st March 2005, the Environment Agency has required accreditation to our Monitoring Certification Scheme (MCERTS) where laboratory soil testing results are submitted to us as part of a regulatory regime for which we have statutory responsibility.

We strongly recommend that MCERTS accredited methods are used for soil testing in activities to do with site remediation, whether carried out on a voluntary basis or to comply with planning requirements. This is particularly important in relation to any waste management issues on the site.

Jackie Harrison Environment Agency

Contaminated Land Working Group Meetings

In recent meetings of the Contaminated Land Working Group, it has been clarified that the EA is a consultee but not a Statutory Regulator for planning applications. This means that MCERTs data may not always be required at the planning stage. Although the EA recommend MCERTS, the final decision is up to the Local Authority.

Some AGS Members feel that all tests should be to MCERTS so that the reports can be used at a later date. At present, the EA is expected to take a pragmatic approach to historical data obtained before the introduction of MCERTS and take account of whether the laboratory is now accredited, and other relevant factors. However, this may not always be the case, particularly for data collected after March 2005, and the need to ‘future proof’ data should be seriously considered.

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Meet NHBC Requirements with MCERTS

The NHBC welcomes MCERTs accredited testing and supports it’s use in association with robust and representative soil sampling strategies when investigating sites affected by contamination. It brings transparency and consistency to the analytical testing techniques and encourages discussion between the consultants and testing laboratories which can only be a positive step forward.

Article Contaminated Land Laboratories

MCERTS

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Tags: Chemical test data chemical testing laboratories MCERTS soils

The Environment Agency have advised that a policy titled ‘Chemical Test Data on Contaminated Soils – Qualification Requirements (307_03)’ has recently been published. The purpose of the policy is to implement the ‘MCERTS Performance Standard for Laboratories Undertaking Chemical Testing of Soils’, which was published in March 2003.

Chemical test data on soils is used by the Agency to support its regulatory activities under a number of regimes, such as Part IIA of Environmental Protection Act 1990, Pollution, Prevention and Control (England and Wales Regulations) 2000 and Waste Management Licensing Regulations 1994. The Performance Standard will be applicable to all laboratories and procurers of analytical services where results generated from the chemical testing of soil are presented to the Agency for regulatory purposes. After September 2004, the Agency expects that all soil testing results submitted will be from methods which have been accredited to BS EN ISO/IEC 17025:2000 for the MCERTS performance standard.

In the interim period, it is encouraged that all data provided to the Agency should be from a testing method accredited to BS EN ISO/IEC 17025:2000 and be accompanied by a brief method description, together with bias and precision estimates.

In addition to the policy, the Agency are producing a document for those who procure soil testing, for example consultants or local authorities, titled ‘Brief guide for procurers of analytical services’ which outlines what is expected of them and why it is required. All the documents mentioned above will be available from the Agency’s MCERTS website at www.mcerts.net.

Any technical queries relating to MCERTS should be addressed to Mike Healy, Technical Advisor, by email (Mike.Healy@environment-agency.gov.uk) and queries relating to the policy itself should be directed to Nicky Skidmore, Land Contamination Policy Advisor (Nicky, Skidmore@environment-agency.gov.uk).

Article Contaminated Land Laboratories

The Extension of MCERTS to Chemical Testing Of Soils – An Update

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Tags: Contaminated Land laboratories MCERTS quality control soil

In January 2003, issue number 45 of the AGS Newsletter contained an article by Bruno Guillaume, of Arup Geotechnics, who outlined the MCERTS performance standard for the chemical testing of soils. The following is an update, and a view from an analytical chemist`s perspective.

On the Environment Agency website reference has been made to the fact that the Agency is aware that it will take time for laboratories to gain approval through the appropriate accreditation process. An eighteen month period, starting from March 2003, has been given for laboratories to bring their soil testing methods up to the MCERTS standard.

During this period laboratories reporting data to the Agency have as a minimum to be accredited to the ISO 17025 standard for the soil test methods. It is also recommended that tests should have a brief method description together with estimates of bias and precision. From September 2004 only data from laboratories that have been accredited to ISO 17025 for MCERTS will be accepted.

Since the last article in the newsletter, Version 2 of the MCERTS standard has been published, and this was available from February 2003. The standard highlights particularly important areas, namely contract review, bias and precision targets, quality control( both internal and external), method validation, and uncertainty of measurement. Important differences from the first version are the exclusion of expected limits of detection for methods, and the inclusion of an improved protocol for validation.

The issues can be confusing but the standard simply aims to establish a level playing field in a competitive market, based on the Agency`s requirements, and to set a minimum acceptable performance. In short the data received by the laboratory`s customers must be accurate, reliable and comparable.

The analysis of soil is complex in terms of the chemistry involved. It aims to determine both macro and trace components in a matrix that is, quite often, dirty in both a physical and chemical context. There is a need to analyse for trace organic and metallic contaminants in soils that contain large quantities of other industrial materials, such as oil or tar, in a background that also contains high concentrations of naturally occurring, or artificially polluted, inorganic compounds.

We all use “parts per million” as routine terminology, but the significance is commonly ignored. 1 part per million is more easily visualised as 1 grain of salt in a swimming pool. When we talk of the concentrations of polynuclear aromatic hydrocarbons (PAH), an important environmental parameter, we often refer to micrograms per kilogram, which is three orders of magnitude lower.

The contaminated land testing industry has grown very quickly, and methodologies have been borrowed from other more well established areas of analytical chemistry, such as food or potable water. The only industry standard for analysis of soils in the UK are the robust and technically sound ” British Gas Methods “, but even these were not designed to tackle the lower end of detection, and do not take advantage of some of the more modern developments in analytical chemistry.

MCERTS effectively defines a standard for the performance of analytical methods, and includes the requirements of ISO 17025 in terms of certification of instrument performance, approved competency of personnel and the accreditation of laboratory procedures and organisation. It means that it is no longer sufficient that the laboratories follow a rigorous UKAS quality system in line with the international standard, but that the methodologies must also be demonstrated as fit for purpose.

The Environment Agency has not, in its standard, adopted the principle of prescriptive methods, as has been the example in the USA, through the so-called EPA procedures. This approach can commit the industry to inappropriate analytical techniques, a long time in their reform once committed to paper, and takes away the flexibility of developing new improvements for the industry as a whole.

It cannot be relied upon that environmental specialists, requiring the services of an analytical laboratory, will have the depth of technical to knowledge to understand the concepts of analytical bias or precision. MCERTS is designed to take away the need for such expertise.

Another variable that stops a customer from being able to compare “apples with apples” is the limit of detection (LOD) quoted. This can vary widely depending on how the laboratory defines it. A sound statistical principle is to use three times the standard deviation associated with a blank, or a sample with a very low concentration of the determinand of interest. This is all carried out interspersed with other standards and samples over eleven separate days. Other lesser definitions than this one seem to describe a “better” LOD, but mislead the customer into thinking they are getting an improved service, and can give false positive concentrations on soils where none of the contaminant actually exists.

All of these concerns are addressed by the MCERTS standard. Precision and bias must be of an acceptable standard, as must LOD. “Recoveries”, namely what happens when a soil is spiked with known amounts of the material of interest and is reanalysed, are examined in the standard to ensure acceptable performance. The validation must be carried out on three completely different soil types with two spiking levels, and include the use of certified reference materials wherever possible. Detailed methodologies, together with a prescribed uncertainty of measurement must also be given.

The Contract Review is the point at which the client`s needs must be understood, and the point at which the laboratory must document them. What does ” Total PAH” mean, or “Total TPH”, and what does the client consider to be the critical level of interest? This is an area quite often poorly addressed, and to which the standard lends some priority.

The laboratory`s quality control also comes under close scrutiny. At least 5% of the resources allocated to a test must be used to ensure validation. In addition the laboratory must participate in as many of the acknowledged external proficiency tests as is appropriate, such as Contest, Aquacheck, and the SPH test scheme. The results of these must be readily available for inspection by the client.

It is generally recognised amongst the community of analytical laboratories that there is a real challenge in order to be able to comply with the new version. The standards relating to bias and precision and, in particular, the guideline that “the limit of detection usually regarded as being fit for purpose is 10% of the concentration regarded as the critical level of interest” are extremely demanding. There are some method improvements required within the industry before these levels of performance can be achieved. Most laboratories, however, will feel a relief that any ambiguity is now removed, so that everyone can compete to provide a well defined product, and be able to market its expertise without confusion.

Whilst addressing the vagaries of analytical results the Environment Agency has also acknowledged the uncertainty associated with other areas, and is considering certification schemes to address field aspects, including sampling. Other subjects, for example the suitability of leachability tests, toxicity assessments and the bioavailability of metals need to be topics for guidance by the regulator.

Article Contaminated Land Laboratories

THE EXTENSION OF MCERTS TO CHEMICAL TESTING OF SOILS

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Tags: analysis Contaminated Land Land Quality Policy Statement MCERTS

Bruno Guillaume, Arup Geotechnics

In October 2001, the Environment Agency launched proposals to extend its Monitoring Certification Scheme, MCERTS to the chemical testing of soils. The aim of the scheme is to deliver quality environmental measurements with product certification of instruments, the competency certification of personnel and the accreditation of laboratories based on an international standard. In its Land Quality Policy Statement (EAS/2703/1/6/Final 3, available on http://www.environment-agency.gov.uk/commondata/105385/lqpol6re.pdf ), the Agency notes that it will only accept chemical testing data on contaminants in soils that has been produced by laboratories that have been accredited to the BS EN ISO/IEC 17025:2000 quality standard for the testing methods used.

The Agency has provided separate MCERTS performance standards in guidance available from www.environment-agency.gov.uk/business/mcerts. To allow reasonable time for laboratories to complete validation of their testing methods to the Agency’s specification, the Agency will implement this policy over a period of twelve months from 1st April 2002. From the 31st March 2003*, the Agency will require that all chemical testing data on contaminants in soils, which is presented to it in support of regulatory compliance, must have an accompanying estimate of bias and precision and a description of the testing method used, with the laboratory being accredited to the BS EN ISO/IEC 17025:2000 standard for the test method.

The MCERTS proposals were discussed at the annual Contest meeting in June at which I was asked to speak on “the client’s view”. There is no doubt that the risk-based approach to contaminated sites and especially quantitative assessment requires greater confidence in data from site investigations. All laboratories should operate quality control and quality assurance schemes with calibrations, blanks, sensitivity checks and duplicate testing. UKAS accreditation is often quoted as evidence of quality assurance, but it gives no indication of the suitability of test for the intended purpose of the end user. Proficiency testing and participation in schemes such as Contest, Aquacheck or LEAP is a far better indication of a laboratory’s ability to undertake tests reliably. However, the results of proficiency testing are seldom available to third parties, such as those organisations commissioning tests from the laboratories. MCERTS has the potential to provide an indication of data reliability with performance standards set by an authoritative body.

Laboratories have expressed concerns over certain aspects of the MCERTS proposals as applied to the chemical testing of soils. Sampling is potentially a far greater source of data errors than is laboratory analysis, and there is as yet no comparable scheme addressing sampling, in-situ and field tests. The performance standards requested by the Environment Agency are too demanding and prescriptive for certain parameters (e.g. limit of detection of 20mg/kg for sulphates) and ill defined for certain parameters (e.g. are “polyaromatic hydrocarbons” represented by the sum of USEPA priority 16 or defined by other means?).

The Environment Agency is considering certification schemes to address field aspects including sampling. It is worth noting, at this point, that the Agency has produced guidance, (including Technical aspects of site investigation, P5-065/TR and Secondary model procedures for development of appropriate soil sampling strategies, P5-066/TR), though this has been poorly publicised.

Accreditation of laboratories to BS EN ISO/IEC 17025:2000 (General requirements for the competence of testing and calibration laboratories) is significant: clause 4.1.2 states that it is the responsibility of the laboratory to carry out its testing and calibration activities in such a way as to satisfy the needs of the client. The requirement for the laboratory to understand the client’s needs is explicit. Currently, too many clients will commission testing without discussing objectives with the laboratory. Unfortunately, the market is driven by price rather than quality and there are still laboratories that offer methods that are inappropriate. An uninformed client cannot distinguish between good and bad service providers. The introduction of MCERTS and accreditation to BS EN ISO/IEC 17025:2000 could act as a catalyst to encourage the engagement of laboratories earlier in the investigation process, thus ensuring that the laboratory methods are fit for purpose.

MCERTS does not specify the methods of analysis, and proficiency testing shows an astonishingly wide variation in results for certain parameters. This is due to the variety of methods in use and economic pressures in a market where there is over capacity, as well as poor parameter definition and lack of performance standards. Method specification through international standards is an extremely slow process and not favoured in the UK. Research has however been undertaken, funded by the Government and the Environment Agency, on appropriate methods of analysis, and the results of this research are still awaited.

Finally, the risk assessment approach to contaminated land requires further guidance which has yet to be provided by the regulators, including suitability of leaching tests, bio-availability and toxicity assessments. The process of investigation and assessment is complex and potential for errors considerable, but MCERTS should at least address one part of the process and raise the importance of appropriate data.

References: Environment Agency, Performance Standard for Laboratories Undertaking Chemical Testing of Soil, May 2002, Version 1 <http://www.environment-agency.gov.uk/commondata/105385/soiltest.pdf> UKAP, Good Regulation and Competitiveness Network – Environment Sector Study, July 2001, <http://www.chemsoc.org/pdf/ukap/enviro.pdf> Hazel Davidson, VAM Bulletin No. 21, 1999, 4 , <http://www.vam.org.uk/news/news_bulletin.asp>

*Note: The intention to implement to this timetable has been withdrawn to allow a more realistic timescale for the accreditation of laboratories. A statement on the EA website reads:

‘Having recently met with UKAS and discussed the concerns of a number of laboratories with respect to the timescales for compliance, the Agency has decided to revise the phased approach to implementation of its requirements to allow a longer lead in time. In addition, the Agency has decided to take this opportunity to review the detail set out in the performance standard with a view to streamlining the additional requirements over EN ISO/IEC 17025:2000 which are already assessed. We will issue a revised implementation policy and performance standard shortly. In the interim, laboratories are urged to seek the accreditation to EN ISO/IEC 17025:2000 for the chemical testing of soils which is already available.