Unlocking Complex Brownfield Sites

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A Team Approach to Unlocking Complex Brownfield Sites
As engineers, geologists and environmental consultants, a large part of our careers is spent working in teams. It allows us to work across different disciplines, companies and sectors; it allows us to work with technical specialists, planners, clients and regulators. The dictionary definition of teamwork is “the combined action of a group, especially when effective and efficient”. This is the nub of WSP’s approach to unlocking complex brownfield sites – essentially, how to use effective teamwork, across disciplines and technical specialisms to deliver significant and tangible benefits in the land development projects we work on.

Where are all the Brownfield Sites?
The Housing & Planning Act 2016 put in place regulations to ‘prepare, maintain and publish a register of land’, effectively a ‘Brownfield Register’, by the end of 2017. The Act compels local authorities to keep a comprehensive register of brownfield sites suitable for redevelopment for housing. Once identified, the local authority will be responsible for securing planning consent on 90% of suitable brownfield land by 2020.

There are a number of criteria that must be satisfied before land can be included in the brownfield register. Most importantly, it must be capable of development and be free from constraints that cannot be mitigated. This will need to be supported by strong evidence of the mitigation of development constraints.

Importantly, the legislation provides ‘Permission in Principle’ status for sites that make it into Part 2 of the Brownfield Register, thereby streamlining the planning process on these complex sites. The Government is hoping that this streamlined planning process will open up more sites for housing development and speed up granting of planning consent.

Keeping this in mind, we think that the introduction of the Brownfield Register will allow us to take a more integrated approach to the assessment of development constraints including potential constraints related to contamination and ground risks in general.

Initial Indications from the Brownfield Register
All local authorities in England were required to prepare, maintain and publish their brownfield registers by 31 December 2017 and the vast majority have done so. The information in the registers is showing some very interesting trends.

In the initial pilot study phase of the publication of the register, 53 local authorities identified ‘suitable sites’ that could provide 273,000 homes. If this is scaled up to a national level, then suitable sites could provide some 1.1 million homes.

We have reviewed the content of the initial pilot study registers. We have looked closely at local authorities located in the South East with a focus on 12 of them. Within these 12 registers, there are 773 sites representing delivery of 44,474 residential units. However, of these, some 63% already have planning permission in place or pending.

Referring to one particular Local Authority register, Medway Council, it has a respectable 45 sites with 1,325 units. However, 35 of these sites are less than 1 hectare, 25 sites are less than 0.25 hectares and, most importantly, 35 sites already have planning permission in place.

The Brownfield Register for the City of Westminster shows a similar trend. It identifies 101 sites within the Borough with a total plan area of almost 35 hectares that could deliver over 6,000 units. However, 72 of these sites, representing 17 hectares and almost 3,500 units, already have full planning permission in place or pending.

So, this raises some important questions. How much new land, without planning consent, will actually come forward from the publication of the brownfield registers? Additionally, with a large proportion of sites identified being less than 0.25 hectares, outside of the major metropolitan areas, will these smaller sites really be of interest to developers?

In relation to the Brownfield Register, we feel that there has been a good start but much more needs to be done to give local authorities and developers the tools to bring brownfield land back into beneficial use.

It is also worth noting that where remediation costs make marginal sites unviable there are emerging funds from Government to support these through the Marginal Viability Fund.

A Constraints-Led Approach to Masterplan Development
In the Brownfield Register, we now have a potential repository of brownfield land that is free from constraints that cannot be mitigated and doesn’t currently have planning consent. Next, we need to develop an appropriate masterplan that will maximise the value and potential of the site.

All too often, sites are presented to technical advisors where the masterplan has been fixed before the contamination and other technical assessments have been carried out. The masterplan is set, the development constraints are understood, and then the bun fight starts over how the conflicting technical requirements of the project can be met. For example, one paradox that we regularly see in conditioned planning consents is a condition maximising the use of SuDS in the drainage scheme with a second condition prohibiting infiltration drainage through made ground. A clear conflict!

A far better approach, a far more cost effective and sustainable approach, is one where the development constraints are screened and assessed and then mapped. Only at that stage is a targeted masterplan developed, working with the identified constraints. This is something that is strongly promoted by Homes England (formerly the HCA). We have worked closely with them in developing an early screening tool that looks at all development constraints and only then will they decide on the proposed masterplan and mix of uses. The result is a masterplan that works with the potential development constraints on a site rather than battling against them with a ‘fixed’ masterplan.

Many of these constraints are interconnected and cannot be treated in isolation. Decisions we make on contamination remediation may have a significant impact on the foundation solution for buildings, the design of road pavements, flood risk mitigation or ecological protection and enhancement. Contamination remediation for domestic gardens, for example, is likely to be simpler and of lower cost if the planning consultant doesn’t decide at an early stage to put them over the most heavily contaminated part of the site.

How NOT to Masterplan a Brownfield Site
Inefficient masterplanning of complex brownfield sites that fails to unlock their potential appears all too frequently. Take, for example, a 12 hectare, former chlorine manufacturing site that was presented to WSP after the first attempt at masterplanning the site failed. The site was being redeveloped for mixed residential, commercial and industrial use as the works were no longer viable and the processes were some 40 years old.

This site had huge development potential but also came with some significant development constraints. All the buildings needed to be decommissioned and demolished; it had a flooding stream running along one boundary; there were sensitive ecological receptors on adjacent land and it had some major geotechnical and contamination issues in the ground.

In arriving at the original masterplan, it seems that very little consideration was taken of any of these potential constraints…
• The housing was placed in the location of greatest mercury soil contamination.
• The heavily loaded commercial buildings were located in an area of weak alluvial soils.
• The ground level car park was located close to the adjacent sensitive ecological receptors.
Abnormal development costs has been estimated at £20m with a long programme of ecological, contamination and ground improvement mitigation measures. Discussions with the local planning authority had been tense and fraught with difficulties, adding further to development costs and programme.

The Client knew that there had to be a better solution and so went looking for alternative advice. This is where WSP became involved.

At the outset, we gathered the whole project team at a workshop to openly talk through the Client’s aspirations, the scheme proposals and the development constraints. A number of low cost, initial technical assessments were carried out to understand the key issues. Through this collaborative approach, a development constraints plan was produced that led to a much improved masterplan. This revised masterplan allowed us to work with the constraints rather than against them, often turning them into opportunities:
• The high sensitivity residential element was moved to a less contaminated area of the site and away from the area of greatest flood risk.
• The areas of greatest ecological interest were allocated to public open space.
• The car park for the commercial element was moved away from the ecologically sensitive area and into the area of greatest flood risk, allowing for temporary flooding of the car park in the design.
• The area of mercury soil contamination was allocated for car parking reducing the remediation requirements.
• The commercial buildings were moved away from the areas of soft alluvial soils, thereby reducing abnormal foundation requirements.
The Council were involved at an early stage in the discussions and played an important part in developing the revised masterplan. This approach locked in their full buy-in and approval of the scheme from the outset. Overall, remediation costs were reduced by 80% and ground improvement, ecological and flood mitigation works were removed almost entirely.

The Opportunity for Developers and their Advisors
The Housing Minister has said that The Housing and Planning Act will be a catalyst for regeneration by simplifying and speeding up the planning process and unlocking brownfield sites for redevelopment that would otherwise be constrained or passed over. The Act is designed to kick start a national crusade (no less) to get 1 million new homes built by 2020 with a concentrated focus on brownfield regeneration. There is a great opportunity for our whole industry to contribute to this aspiration with a sustainable, collaborative and solutions-led approach to land regeneration.

The opportunity for land developers is clearly around the effectiveness and efficiency of addressing development constraints in this way, and the associated programme and costs savings. The opportunity also lies in sites being included in the Brownfield Register and obtaining Permission in Principle through that designation.

Using the integrated multi-disciplinary approach outlined above, we see a great opportunity to improve the outcomes of the masterplanning process. WSP’s view is that early screening and ranking of the technical risks is critical to understanding development priorities. We also feel that early collaboration is essential to achieving our clients’ development aspirations – get around the table and talk!

The industry needs to challenge development strategies for difficult sites and innovate in our solutions to address complex development constraints. And we need to engage with the regulators and planning authorities to get them on side and address their concerns.

In essence, there are three simple concepts we feel should be considered on all brownfield site developments:
1. Carry out technical screening at the earliest opportunity so you don’t paint yourself into a corner with a constrained masterplan.
2. Ensure that the project technical advisers operate as an integrated team, talking across disciplines and consulting with regulators to identify and address development constraints as early as possible in the process.
3. Aim for positive development outcomes using the team’s expertise to work with potential development constraints rather than against them.

As mentioned at the outset, the results of teamwork can be measured against the effectiveness and efficiency of the outcome. “If everyone is moving forward together, then success takes care of itself.” – Henry Ford. Useful advice in car manufacturing and also in unlocking complex brownfield sites.

This article was contributed by Andy O’Dea, Technical Director – Ground Risk & Remediation, WSP and featured in the March/April issue of the AGS Magazine, which can be viewed here.

Article Contaminated Land Laboratories

The problem of made ground

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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 (

Article Business Practice Contaminated Land Executive Loss Prevention

Report of AGS Chairman’s visit to ASFE Conference

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At the invitation of the President of ASFE, I attended the ASFE Autumn Conference in Scottsdale, Arizona. The conference was held over two days (Friday and Saturday) with Board committee meetings held on Thursday and Sunday. The whole event was very well organised, extremely sociable, informative and thought provoking. I gave a presentation to the Conference of the current initiatives and concerns of the AGS which was well received.

Perhaps most surprising to me was just how many of the issues of concern to ASFE were common to the AGS. In particular this was illustrated by concerns over the trend in the Client community to expect “perfection” from their geotechnical/ geo-environmental advisors. Such Clients then appear hold reasonable (?!) expectations of recovering any financial over-runs from their advisors even if such costs have not resulted from any negligence by that advisor. ASFE have just published a Handbook ‘Limitation of Liability’ which although specifically related to the US experience, also provides much useful information for the UK practitioner. A copy has been given to the AGS Loss Prevention Group who will be looking to see how best to utilise this tool in the UK market. [You can see the ASFE publication list and order copies on].

Interestingly, and contrary to what I had anticipated, the levels of liability agreed by parties in the US are far lower than those currently being accepted here in the UK. For example, many ASFE members are able to limit their liability to the level of fee or to levels as low as $50,000.

Training is also an issue which is concerning the industry on both sides of the Atlantic. The availability, consistency and quality of training for members and employees is recognised as being critical in ensuring the continuing professional development of the industry. To its credit ASFE has over 50 training presentations (‘brown bag talks’) on its web site for use by its members. I believe that the AGS now needs to give further consideration to its role in the provision of training to the industry.

Geo-environmental aspects are assuming an increasing importance for both ASFE and AGS members. In the US geo-environmental work is now more important than geotechnical for the majority of ASFE members. This is reflected in moves in the US to create an “Institute of Brownfield Professionals”. This proposal essentially mirrors the SiLC [Specialists in Land Contamination] registration scheme which has been set up in the UK with the active support / participation of the AGS. Also of current concern to ASFE have been recent developments at the Environmental Participation Agency and the specification of a Standard – which defines the amount of site investigation needed on Brownfield sites. The Standard refers to only a simple option [the ASTM – All Appropriate Inquiry (AAI)]. ASFE has concerns that this signals movement at the EPA from their previous position of preferring ‘performance based standards’ to one of the ‘prescriptive standards’. Again, this has parallels in the UK and it will be important for the AGS to monitor the implementation of the Model Procedures for the Management of Contaminated Land (CLR11) by the various regulators, to ensure that this document does provide a framework for assessment and not a straight jacket.

One element of the conference that did surprise me was the very open/honest atmosphere that ASFE has created over the years. This was exemplified by the presentation of several ‘Case Histories’. These presentations by ASFE members describe in unambiguous words of few syllables how and why things went wrong on their projects which led to liabilities and costs against them. The topics covered ranged from; foundation/pavement design, a de minimus site investigation and to a case of unfair dismissal [in this instance a claim for $25 million by the employee who had been employed for less than 1 year!]. In each case the lessons learned by the member company were clearly spelt out for the benefit of all. The question and answer sessions were particularly illuminating.

In the UK we are perhaps less prepared to wash our dirty linen in public. However, these sessions were so powerful and reinforced the written advice that both ASFE and AGS are giving to members that I believe we would do well to adopt this practice to our own Members Day. Watch this space!

This is now the third time that the AGS Chairman has attended the ASFE conference and the potential benefits are beginning to be realised. There is much more still to be gained by developing this liaison further over the coming years and I am pleased to be able to report that Dan Harpstead, the new ASFE President, was a guest speaker at this year’s AGS Members’ Day.

Hugh Mallett

Article Contaminated Land

The Landfill Directive – Nightmare or Opportunity

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[These notes were made after attending an EIC Seminar on the Landfill Directive held on 31 March 04. They represent the view of the author and do not necessarily reflect the views of the AGS.]


The European Landfill Directive (EC 2003/33) is due to be transposed into UK Law by 16 July 04, and be fully effective from 16 July 05. Transition arrangements for waste acceptance criteria will be in place from July 04 to July 05.

Legislative Background

The Landfill Directive sits with the Hazardous Waste Directive and the Waste Framework Directive.

The latter two have been in force for a number of years but will be effected by the Landfill Directive.

An updated European Waste Catalogue (EWC 2002) has now been published and this sets out which materials are (or potentially are) hazardous.

The EWC gives absolute and mirror entries. Absolute are classified as hazardous irrespective of their composition whereas mirror entries need to be checked for contaminants (both type and concentration).

The classification links back to CHIP3 regulations which are published by the HSE.

Waste sent to landfill will now be classified as hazardous or non-hazardous. The use of ‘inert’ seems no longer applicable.

Waste acceptance criteria (WAC) are shortly to be approved by the European Council and these will link into the Landfill Directive. The WAC require leaching tests to be carried out and limit a number of criteria which cannot be exceeded (eg TOC never above 6%). WAC is not due to be introduced until 2005 and interim criteria will be established to fill the gap.

The principle regulations

  • Pollution Prevention and Control Act 1999

  • The Landfill (England and Wales) Regulations 2002

  • The Landfill (Scotland) Regulations 2003

  • The Landfill (England and Wales) (Amendment) Regulations 2004

The Landfill Directive’s Rules

All hazardous waste sent to landfill must be pre-treated from July 04. No definition has been given as to what this means. However some reduction quantity and / or hazardous nature will have to be achieved.

Dilution (eg mixing of non-hazardous with hazardous) will be illegal from July 04.

Co-disposal is illegal from July 04 and sites will only be licensed to receive hazardous or non-hazardous. The most significant issue is that the number of sites licensed to receive hazardous waste will reduce from slightly less that 200 to about 10. Of these none re are located in Wales or the South East of England.


The latest definition of waste within the UK is that waste ‘shall mean any substance or object which the holder discards or intends or is required to discard’.

The hierarchy of waste treatment is re-use, reclaim, recover and recycle.

A waste remains as waste until complete recovery has taken place or the substance is put to its final use. It does not cease to be waste if someone intends to use it, if it has a value, if it is ready to recycle or if it is not polluting.

Environment Agency guidance indicates that all excavated contaminated land would be classified as waste.

It would appear that even excavated ‘clean’ soil on site may be classified as waste and thus and re-use would fall within the waste management licensing regulations.

What it all means

Despite the assembled hoard of experts at the Seminar, no-one really knew!

Confusion and uncertainty surround the issue, although something must happen in July to avoid serious Government embarrassment.

Some theories were:-

  • Landfill prices for hazardous waste are likely increase fourfold.

  • Haul distances will increase from an average today of 44 miles to 87 in 05.

  • Remediation by ‘dig and dump’ will become non viable in most situations

  • On-site remediation will to have increase dramatically but there is insufficient capacity in the UK to accommodate the probable demand

  • Many brownfield sites are likely to become non viable for development and consequently the Government objective of 60% development on Brownfield sites may be jeopardised.

Article Business Practice Data Management

The CML initiative – how does it affect geo-specialists?

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In order to prevent homes being sold and occupied before completion, the Council of Mortgage Lenders (CML) initiative was implemented in April 2003 and has wide ranging implications for anyone involved in property transactions involving brownfield sites, and in particular house builders. Before providing a mortgage on a property, funders now require confirmation by solicitors and licensed conveyors acting on behalf of purchasers, that a new property has been signed off or ‘finalled’ (see below) and has a full warranty in place. This is often an NHBC warranty or similar from another warranty provider.

Prior to April 2003, the standard approach to brownfield redevelopment was to remediate the site with development progressing behind the remediation works as sections of the site are completed. It is usual to carry out appropriate validation testing by a third party, typically a geo-environmental consultant, to demonstrate compliance with outstanding planning conditions relating to contamination. On completion of the whole site, the planning authority and its statutory consultees, including the Environment Agency, would then review the validation data and indicate their acceptance of the work as complying with the relevant planning conditions. In addition the consultant responsible for the validation process may also have been required to complete an NHBC Form of Validation, or similar, to enable the developer to obtain a warranty for the property. Therefore, on medium size and large developments, many of the properties would be completed and occupied before the site warranty was signed off. This will no longer be possible.

In order to prevent developments becoming unmortgageable, remediation designers need to take a staged approach to both remediation works and validation, so that sites can be completed in sections. Each section is then signed off individually on completion. However, this approach has to be agreed in advance with the Regulators so that the implications of phasing on both completed areas and on-going remediation works can be considered.

It is suggested that phasing is introduced as a concept in any remediation statements and mirrored in planning applications, to avoid any future confusion as to how the site is to be redeveloped and released for sale. This may have been implied previously, but must now be clearly identified in development and remediation proposals. This places an onus on developers to have well developed plans before planning submission, where possible, so that changes to proposed phasing are minimised, or to ensure that proposals are sufficiently flexible to incorporate future changes, without compromising previously ‘approved’ phasing and remediation methodologies.

Similarly, environmental consultants acting on behalf of developers should include reference to validation also being completed in phases. In this case, validation documents may be structured such that they can be issued in sections relating to each individual phase. For large projects the validation report may be a series of volumes or a ‘log book’ style document with several addenda.

By taking this approach, which in reality only represents a minor but potentially critical modification of previous protocols, the planning authority and statutory consulates will be accepting the premise of staged development and validation and should be well placed to be able to sign off planning conditions piecemeal. As a result, delays to ‘finalling’ and the all-important sale should be prevented.

Jo Strange Card Geotechnics Limited

Article Business Practice Contaminated Land

Environment Agency Draft Policy on “Building on or Adjacent to Gassing Landfill Sites”

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This draft document was published as a draft for consultation in July 02. It sets out EA policy on how they should respond to consultations from planning authorities regarding sites on or adjacent to landfills. The major concern is the reliance on the trigger concentration of 1% for methane where housing development is proposed. The guidance highlights that this applies to sites with the potential to generate ‘significant quantities of gas’. Although the document is silent on a definition of ‘significant quantities’, recent thinking presented by the EA suggests a reservoir of gas in the ground not necessarily associated with active generation would be considered ‘significant quantities’.

AGS is concerned that this policy could prove very restrictive and could result in a significant number of brownfield sites not being developable.

AGS is keen to establish the experience of members as to whether this policy is creating obstacles to development in order to make a more strenuous approach to the EA. If anyone has any useful experiences (either one way or the other) please send details to; Peter Witherington (