Guiding the Remediation Process
Article from Sustain’ magazine – Vol. 4 Issue 4
www.sustainmagazine.com
Sustain' takes a look at the latest revisions to the Welsh Development Agency's Manual on the Management of Land Contamination
Most practitioners agree that managing land contamination in a way that protects health and the environment, meets client and legal demands, manages public expectations and controls costs, can be a tall order! This is particularly so for large, complex sites which have a long and varied industrial history and where uncertainty about the actual condition of the ground may be very high. Technical uncertainty is damaging because it can undermine commercial confidence in risk assessment and remediation outcomes, and an unwillingness to invest or trade in land. What is more frustrating, however, particularly for funding organisations like the Welsh Development Agency (WDA), is that commercial reluctance to deal in this type of land may stem more from concerns about the standards of professional practice applied to projects, than the characteristics of the land itself.
Having encountered this problem on a number of sites during the 1980s, the WDA recognised the need for clear and comprehensive guidance on the remediation process. This resulted in consultants being commissioned and, in November 1993, the WDA published its 'Manual on the Remediation of Contaminated Land'. The Manual set out the WDA's view of what constituted good technical practice in the management of contaminated land in the context of WDA-funded land-reclamation schemes. The Manual was directed at all those involved, including WDA and Local Authority project managers, developers, advisors and contractors; its aim was to improve overall standards in the commissioning and execution of projects.
The Manual was well received in Wales, elsewhere in the UK, and overseas, as a concise and authoritative account of how best to approach contaminated sites and ensure confidence in the risk assessment and remediation process. Since 1993, however, there have been key developments across a broad range of fronts that have prompted a revision of the Manual. These have included:
• The emergence of 'sustainability' as a key policy
driver in construction and development activities;
• The introduction of a new regime (Part IIA of the Environmental Protection
Act 1990) for the regulation of historically contaminated land and;
• The publication by DEFRA, the Environment Agency and others, of further
detailed good-practice guidance on a variety of issues, including risk assessment
(eg: for human health, ecological
systems and the water environment), site investigation (eg: BSI 10175) and remediation
(eg: the practical demonstration of new remediation methods facilitated through
CL:AIRE, Contaminated Land: Applications In Real Environments).
WDA Policy and Objectives
The WDA has held responsibility for the public-sector programme of Land Reclamation in Wales since its formation in 1976. Improvement of the environment and the provision of development sites have been key functions in the drive to achieve economic success in Wales and to sustain one of the best business climates in Europe. These functions have also contributed to the improved prosperity of communities as part of the wider regeneration objectives.
The Manual addresses one of the critical components of successful regeneration. It will sit alongside practical guidance documents to be published by the WDA on sustainable development and design quality; the overall objective of the Agency being to provide integrated solutions to environmental, social and economic needs.
The remediation solutions for each project must ensure that the site is suitable for its intended use and that proposals comply fully with current legislation and guidance. In particular, there must be appropriate procedures in place to demonstrate that the investigation and risk-assessment stages have provided a robust interpretation of the characteristics of the site and a valid conceptual model from which the constraints to future use can be determined.
Developing stakeholder confidence must be an integral part
of project management. The Manual advises that stakeholders must be identified
and engaged as early as possible to identify their concerns, aspirations and
objectives. Furthermore, the dialogue process will be underpinned by systematic
record keeping and reporting in a style appropriate for the parties concerned.
Such an approach will ensure that the project delivery team, regulators, end
users, insurers and third-party funders have full access to all relevant information
for the site.
Structure and Content of the Manual
The revised Manual takes into account recent legal, policy and technical developments in the contaminated-land field while retaining many of the features of the original WDA guidance. It also introduces new material, such as 'Project Planning', underscoring the importance of good preparation in ensuring a successful project outcome, as well as extended advice on such topics as ecological risk assessment, risk communication, procurement and contract management.
The main technical content of the Manual is structured around the three main components of risk-based management, all closely linked to the key WDA funding approval stages.
Risk Assessment and Site Investigation
This Chapter covers the technical processes involved in deciding whether land poses unacceptable risks to human health or the environment. It makes an important distinction between the conceptual process of risk assessment – how to determine the level of risk, and what, where, how and how much information should be collected to support risk assessment – and the practical activities used to gather the relevant information.
The Chapter considers the main components of risk assessment, that is, preliminary risk assessment (involving the development of the 'conceptual model') and detailed risk assessment (using either generic or site-specific assessment criteria, or both). The Manual also advises on key data-gathering techniques, including desk-based research and site reconnaissance, intrusive site investigation, sampling and testing. A separate section deals with practical ways of communicating risk-based information to stakeholders.
Selection and Preliminary Design
Chapter 4 deals with the structured evaluation of different options for reducing or controlling any unacceptable risks that have been identified through risk assessment, and how appropriate options can be further developed, either singly or in combination, into an outline remediation design.
It advises on defining remediation objectives and identifying practical constraints on remediation (such as site access or timescale), how to identify feasible options and apply evaluation criteria to arrive at defensible selection decisions, and how to prepare the outline design.
Detailed Design and Implementation
This Chapter describes how to transform the outline design into the practical steps needed to deal with contaminants, make the site suitable for use and demonstrate that remediation is effective both at the time of installation and over the planned design life.
It considers the preparation of an implementation plan (that is, a plan covering all aspects of the proposed remediation works) and all the main components of the implementation stage itself, such as procurement, detailed design, supervision and the verification of completed work. Long-term monitoring and maintenance requirements are also addressed.
Availability
The intended 'audience' for the Manual is principally WDA management staff and
the recipients of WDA funding for remediation projects, for example Local Authorities.
External advisers for projects (eg: technical consultants) will also be required
to adopt the procedures outlined in the document. The requirements will also
be of interest to regulators, insurers and other external bodies with an interest
in the quality of remediation.
As a comprehensive guidance document on good technical and management practice, it will be of value to other organisations (public- and private-sector bodies, representative bodies, local communities, etc… ) and the WDA will be marketing the document in due course.
Details are available from the WDA – telephone on 08457 775577 or by email at enquiries@wda.co.uk
This article was written by:
Steve Smith, Senior Land Reclamation Manager, Welsh
Development Agency; Mary Harris, Technical Development Director, Land &
Water Quality, Casella Stanger; Phil Crowcroft, Director of Contaminated Land,
Entec UK Ltd; Judith Lowe, Independent Consultant; Jennie Stothert, Principal
Consultant, Entec UK Ltd
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