NEWS AND UPDATES November 2008

Well, we’re now into our ninth year at Terrenus and it seems the more things change the more they remain the same. Many of the issues raised in our last news page are still pertinent, although the emphasis has changed to an extent. This note, hopefully, will bring you up to date on the changes, some of which we have taken on board at a fundamental level to ensure our services help you clear the planning or development hurdles that might arise as a result. Contaminated Land Management and Assessment

As you may be aware there is an ongoing review of the policy and modelling strategies used to assess the risks associated with contaminated land, which were first mooted by DEFRA for consultation at the end of 2006. The initial consultation looked hopeful that we would see revised guidance issued late in 2007 that would have resulted, by and large, on higher and, therefore, less conservative, Soil Guideline Values.

There were, however, significant problems along the way, not the least of which was the resignation and replacement of the entire DEFRA contaminated land team. In addition, the Health Protection Agency advised that some of the proposed changes were not advisable as they would compromise the aim to protect human health. These and other factors have led to an ongoing review that has resulted in the withdrawal of CLR Reports 7 to 10 and, more importantly, the published Soil Guideline Values!

New publications have been issued providing a revised background for modelling risk to human health, including revised statistical procedures and a new CLEA UK model (software). Do not expect to see any new SGV’s (if at all) until Spring 2009.

In the absence of approved SGV’s most Local Authorities continue to accept the old numbers in planning applications. I will issue an update as and when things develop further.

For our part our director, Fraser Duff, is a member of a Scottish Government Short-Life Working Group considering the application of the revised framework in Scotland. This allows us to contribute to the system and, where possible, suggest improvements. It also allows us to keep track of the latest developments, which we will communicate when we can.

We also believe SEPA are on the cusp of issuing new guidance on the assessment of risk to the water environment, including groundwater, so watch this space. With regard to planning applications the Local Authorities, as regulator, are now becoming more focussed on contaminated land issues nationwide. In particular they are more insistent on the provision of properly constructed Conceptual Site Models and a full assessment of risk to the water environment as well as human health. This insistence is supported in some cases by published guidance setting out the requirements for the investigation of potentially contaminated land by individual Local Authorities. Where available, this guidance helps developers understand what is required and should reduce the number of reports returned by a Local Authority as it is deemed to be inadequate.

Waste management on contaminated sites has also not yet been resolved to everyone’s satisfaction. There is a fundamental difference in approach between the Environment Agency in England & Wales and SEPA in Scotland. The EA have issued guidance that is intended to clarify and ease the re-use of materials on site. SEPA, however, have doubts that this guidance complies with European directives and have not, therefore, adopted a similar system in Scotland. The existing system of management and exemptions is generally considered appropriate by SEPA and, until we receive further clarification this approach will continue to be adopted in Scotland. As members of the Environment Industries Commission (EIC) our staff participate in two lobby groups looking at both contaminated land and waste issues. The groups actively consult with the policy makers and regulators, including the Local Authorities, SEPA and the Scottish Government. Topics currently under discussion include the progress of the contaminated land modelling revisions, the change to planning guidance in respect of these revisions, the assessment of risk to the water environment (particularly groundwater) and the definition and re-use of waste on contaminated sites.

There is also a push by various bodies for better and more transparent training and a professional qualification in contaminated land assessment and, also, brownfield land. We are keeping a close eye on progress and are likely to be involved in the consultation and development process in due course.

Invasive Plants

Such plants are gaining a higher profile in terms of their impact on development sites, particularly with respect to delays to development that are likely to arise due to eradication procedures.

We were recently involved in the validation of an accelerated Japanese Knotweed eradication programme in conjunction with the contractor, Thurlow Countryside Management Ltd and the ecologist, Mackenzie Bradshaw Environmental Consulting. The process eradicates the knotweed within one growing season but requires a robust verification and validation process, which will continue through the earthworks when development commences. If you require further information on the process please do not hesitate to contact us.

Flooding and Flood Risk Assessments

Two broad matters should be kept in mind in this arena:

Firstly, as we noted in the last update, the issue of flood risk and the standards that a developer is being asked to meet are becoming ever tighter. This problem has been accentuated by the general workload and ‘funnel’ effect by the Council regulator and SEPA as a consultee. Couple this with the fact that regulators and statutory consultees are becoming more risk averse and you have a system that is struggling to deliver to any practical Planning deadline. Whilst a flood risk report may be completed within three or four weeks the discussions leading to acceptance by the authorities can take months.

Our advice to all our clients with respect to flood risk is that you commit to a robust flood risk assessment of your site, that you know your Council’s stance on flood risk and that you plan for at least some discussion and revisiting of any adopted mitigation measures prior to approval being granted.

Secondly, the new European Directive 2007/60/EC on the assessment and management of flood risks entered into force in November 2007. This Directive requires Member States to carry out a preliminary assessment by 2011 to identify the river basins and associated coastal areas at risk of flooding.

In response to the Directive the Scottish Government will introduce a Flooding Bill to modernise the flood risk management system in Scotland. The government are currently at stage 2 of the process and intend that the Bill will become Scots law by December 2009.

The ramifications of this Bill will be extensive with SEPA designated the ‘competent authority’ to oversee the process of implementing the legislation. SEPA currently wish to avoid all development within the functional flood plain and do not readily accept any form of compensatory storage. The designation of ‘functional flood plain’ will therefore become a key matter in this process and the issue of blight for sites on the periphery of water courses is likely to become important in the coming months and years.

Our director, William Hume, has previously been part of the Scottish Government consultation process for the proposed flooding bill in order to raise our clients concerns. William now serves on the Scottish Property Federation Building Standards & Sustainability Committee which will continue to press the government to adopt an economic and engineering solution to the problems of flooding as well as a scientific one.

SuDS

Regarding the issue of Sustainable Drainage Systems (SuDS) these are as you know, firstly measures to treat any potentially contaminated runoff from the site and secondly to attenuate site runoff to alleviate potential catchment flooding. The latter element lies in the hands of the local authority and the standards vary considerable across Scotland and the UK. By calculating site rainfall runoff from first principles we can reduce you attenuation requirements by a significant percentage.

As above, our advice is to undertake a suitable assessment and to report the two elements of the SuDS in two separate parts. In addition, now is the time to explore innovative methods of water attenuation that can reduce the overall costs of SuDS implementation.

More recently we have seen a change (and improvement) in the way Scottish Water approach the issue of SuDS. The upshot is that if you address the drainage strategy as a whole in the early days of a development it may be less of a problem in terms of construction timescales and the Planning process.

Ground Engineering

We have recently encountered resistance from regulatory bodies when considering foundation solutions for proposed residential developments underlain by adverse ground conditions. The presence of thick made ground deposits which are subject to sub-surface obstructions is not an uncommon occurrence in the development of former heavy industrial sites however these conditions can cause significant problems for new foundation construction. Whilst penetrative methods such as vibro improvement or even the adoption of piled foundations are clearly technically feasible there are significant cost uncertainties involved owing to delays or even damage to equipment due to obstructions. Such uncertainties are clearly undesirable for prospective developers.

Impact compaction techniques may be appropriate for such conditions however factors such as the depth of made ground and the proximity of sensitive structures need to be considered. Dynamic compaction is the most effective of these techniques for maximising the depth of treatment although the large weights and drop heights involved can result in prohibitive stand-off distances. Smaller plant such as the rapid impact compactor or rolling compactor modules are increasingly adopted but use for residential development is relatively untried both worldwide and in the UK.

There are clear advantages to the use of these techniques but until some project experience is established for residential development it is unlikely that wide use will be realised. Until this time, it would appear that proposals involving these methods will be met with onerous requests for technical justifications and long term settlement monitoring regimes which developers are, understandably, currently unwilling to provide.

Our News

John Shelton, a graduate Environmental Scientist, and Francis Ocansey, a hydrologist, have joined us as Consultants earlier this year. These changes bring us to 15 staff and allow us to provide an enhanced service to our Clients.

Willie and Fraser (along with one other brave member of staff) again completed the Pedal for Scotland Glasgow to Edinburgh bike ride in September (our third year). The weather was very kind in marked contrast to the 2007 event, when it poured down all day. The guys will continue to participate, as it allows them to pretend that the ageing process can be postponed once more.

Keeping the tradition alive, a hardy sextet of Terrenus staff ‘volunteered’ to take part in the Raft Race, the climax of the RNLI charity week at Portpatrick. Arriving early, a number of the team found the comfort of the pub (and associated beer and chips) almost too much to give up and more than a few detracting murmurs were evident as the team T-shirts were donned in the chill harbour air. Under a hail of eggs, flour and water bombs Team Terrenus won through in the first heat and kept the remarkable run of reaching the final each year firmly alive. The level of physical exertion told however with several team members becoming ‘reacquainted’ with the recently consumed BBQ grub. Expectations were running high but the competition (firemen, rugby players etc.) proved too strong and Team Terrenus had to settle for last place in the final.