Evaluating evaluation trenching in archaeological projects

Historic environment assets, whether designated or not, are significant material consideration in the planning process. Archaeological Written Schemes of Investigation (WSIs) are produced as part of the development process and follow a generalised workflow from Desk based Assessments, Geophysical Survey, Evaluation Excavation, Mitigation Excavation, Post Excavation Assessment and Analysis, through to Reporting and Publication. Although each of these steps is important, arguably the phase of Evaluation Excavation (trenching) is pivotal. Not only is it the first time archaeologists investigate the nature of the deposit sequences and archaeological remains, but more critically, it provides the data on the nature and distribution of historic environmental resources, which determines the methodology of the full mitigation excavation. Despite the prominence of evaluation excavation within the archaeological process, scant research has been undertaken on the effectiveness of current strategies for the detection of archaeological remains, and the importance of different depositional environments (e.g. urban, alluvial) to the process. An often quoted figure of 5% by area of a development site is derived from an early study (Hey and Lacey 1999), and a 5% sample is a typical figure promoted as an archaeological condition. However, given the development of methods of geoprospection for shallow environments (e.g. large area magnetic surveys on chalklands), and a much improved strategy for the deposit modelling of deeper accreting sediments (e.g. urban, alluvial environments), it is time to revisit the process of evaluation trenching. Ultimately, the effectiveness of evaluation strategies needs to be analysed and its application within the archaeological process refined.


Research questions
The aim of this PhD is to assess the usefulness and limitations of evaluation trenching in different environment types, for the detection of different archaeological resources. This can then allow the development of better strategies of evaluation trenching, and possibly a clearer relationship between different evaluation designs and other archaeological methods, e.g. gradiometry or deposit modelling. Ultimately, this will lead to better holistic archaeological programmes within the developer funded sector and better yields from archaeological programmes.
The aims of this PhD will be addressed through five fundamental research questions (i-v)
i. What evaluation trenching strategies are suitable in complex (accreting) depositional environments and how much evaluation excavation is required in conjunction with a deposit modelling framework for these environments?
ii. What evaluation trenching strategies are suitable for archaeological detection on dryland (shallow bedrock sites, e.g. chalk) and how should it be applied in conjunction with shallow geoprospection methods suitable for dryland shallow bedrock areas?
iii. What are there different practices for evaluation trenching and how do these compare in their effectiveness for the identification of historic environmental resources?
iv. What is the ability of evaluation trenching to detect small, less obvious archaeological features from earlier periods, e.g. Creswellian flints, Mesolithic features?
v. Is the 'industry standard' of 5% evaluation excavation strategy effective?

1. Academic beneficiaries: The CDT will develop scientific and engineering excellence in the domain of cultural heritage scientific and engineering research and more fundamentally in the enabling domains of imaging and sensing, visualisation, modelling, computational analysis and digital technology. While the CDT focusses on the complex materials and environments of the arts, heritage and archaeology, it will be broadly influential due to the range of novel methods and approaches to be developed in collaboration with the Diamond Light Source and the National Physical Laboratory. The establishment of a student and alumni-managed 'Heritage Science Research Network', will enable CDT's cross-disciplinarity to bridge EPSRC subject boundaries impacting scholarly research in the arts and humanities and social sciences.
2. Heritage beneficiaries: The CDT will have a transformational effect on public heritage institutions by dovetailing 'Data creation', 'Data to knowledge' and 'Knowledge to enterprise' research strands. The resulting advances in understanding, interpretation, conservation, presentation, management, communication, visualisation of heritage, and improved visitor participation and engagement will lead to significantly improved public service and value creation in this sector. This will sustainably boost the cultural heritage tourism sector which requires significant heritage science capacity to maintain the UK's cultural assets, i.e. museum, library, archive and gallery collections and historic buildings. 15 globally leading heritage Partner institutions (both national and international) will contribute to dissemination through established and new heritage networks e.g. the EU Heritage Portal (http://www.heritageportal.eu/).
3. Industry, particularly three crucial sectors: (i) sensors and instrumentation, which underpin a wide range of industrial activity despite the small size (UK Sales £3Bn), and are a key enabling technology for successful economic growth: 70% of the revenues of FTSE 100 companies (sales of £120Bn) are in sectors that are highly dependent on instrumentation; (ii) creative industries, increasingly vital to the UK with 2M employees in creative jobs and the sector contributing £60Bn a year (7.3%) to the UK economy. Over the past decade, the creative sector has grown at twice the rate of the economy as a whole; (iii) heritage tourism sector contributing £7.4Bn p.a. to the UK economy and supporting 466,000 equivalent jobs. Without the CDT, this crucially important economy sector will experience an unsustainable loss of capacity. The impact will be achieved in collaboration with our Partners: Electronics, Sensors, Photonics KTN, TIGA and Qi3, a technology commercialisation, business development and knowledge transfer company.
4. Public: The intensive public engagement activities are built into CDT including dissemination and engagement events at heritage institutions, popular science conferences and fora, e.g. Cheltenham Science Festival, European Science Open Forum and British Science Festival, as well as events organised by the HEIs' Beacon projects (e.g. UCL Bright Club). Cross-cohort encouragement to engage in these events will realise the substantial potential for the CDT to popularise science and engineering. More widely, visitors and users of heritage will benefit from the development of new and more engaging presentation tools, and pervasive and mobile computing.
5. Policy: SEAHA will engage with policy makers, by contributing evidence to policies and research agendas (the PI is actively involved in the EU JPI Cultural Heritage and Global Change, in which she advised on the development of the EU Cultural Heritage Research Agenda endorsed on 22/03/2013) and develop policy briefings for governmental and parliamentary bodies. The CDT is also a strategically important development of the AHRC/EPSRC Science and Heritage Programme ensuring continued global UK leadership in the SEAHA domain.