Generic brief for an archaeological evaluation (trial trenching)

Last updated: 1 July 2023

5. Project design - 'written scheme of investigation'

Trial trenching should be undertaken in accordance with the Standard and Guidance for archaeological field evaluations" published by the Chartered Institute for Archaeologists (CIfA, 2014).

The project must be governed by a project design which has been agreed in writing by the Council Archaeology Service (Written Scheme of Investigation or WSI). The WSI must be contractor specific. Whilst we will accept WSIs from consultants to inform the scope, the final document must be produced by the appointed contractor.

The WSI should be based on a thorough study of all relevant background information (especially assessment and evaluation reports, historic maps and data held or referenced in the HER). Please note that online platforms such as Buckinghamshire’s Heritage Portal and MAGIC are not licenced for commercial work.

The WSI should conform to the guidelines set out in paragraph 3.2.17 of the CIfA guidelines and should in particular specify:

  • an archaeological background, utilising an up to date Historic Environment Record search. This data must be obtained direct from the Buckinghamshire HER team, and is licenced for a specified time to a specific organisation. Data which is not covered by the licencing terms and conditions must not be used
  • the project's objectives
  • fieldwork methodology - see Section 6. This must include the location of trial trenches and any constraints (to be shown on a plan). The extent and positioning of trial trenches required will depend upon the project objectives, nature of the archaeological interest, nature and location of groundworks and constraints. On some sites it will be possible to target specific archaeological issues, such as the potential for medieval occupation along a street frontage. Simplistic mechanistic application of percentage samples is not encouraged without consideration of the site specifics. Trenching samples should therefore be ‘as appropriate’. In addition a contingency for additional trenching should normally be allowed for, typically 20% on top of the basic trench length or 50m, whichever is the greatest
  • any contractor specific policies/methodologies proposed, for example Selection Strategies or digital recording practices
  • procedures for project management (to follow the principles set out in Management of Research Projects in the Historic Environment (MoRPHE) (Historic England, 2015))
  • the expertise of the project team. The project manager should ideally be a named Member of the Chartered Institute for Archaeologists (MCIfA) who is adequately qualified to manage the required archaeological work in line with the guidance set out in the CIfA code of conduct or can demonstrate an equivalent level of competence. The composition and experience of the project team should be described. Specialists should be identified where required (for example for finds and environmental work). CVs should be supplied outlining the relevant qualifications and experience of key personnel - where relevant this should include specific reference to knowledge of particular periods and local/ regional traditions. Note: Specialists should be able to demonstrate a relevant qualification and track record of at least 3 years continuous relevant work (or equivalent) and appropriate publication. In appropriate circumstances, less experienced staff may conduct work under the supervision of well-established and widely recognised specialists
  • an outline of the proposed timetable and staff resources. Whilst this can in general be non-binding and presented "for information only", a final confirmed maximum timeframe of 18 months of the completion of the field work should be included, unless a revised completion date is agreed in writing with BCAS
  • reporting arrangements - see Section 7
  • archiving arrangements - see Section 10