Off list reply which may be of interest – forwarded with permission.

 

 

 

Dear Nick and Graham,

 

Sally has forwarded your posts to Andy Thomas and I, as Archaeological DC officers in Cambs, for an opinion.

 

Have you seen a copy of Lock and Molyneaux’s 2006 “Confronting scale in archaeology : issues of theory and practice” http://www.worldcat.org/title/confronting-scale-in-archaeology-issues-of-theory-and-practice/oclc/191891425

Or

 

Hey and Lacey’s 2001 “Evaluation of archaeological decision-making processes and sampling strategies : European Regional Development Fund Interreg IIC - Planarch Project”

http://www.worldcat.org/title/evaluation-of-archaeological-decision-making-processes-and-sampling-strategies-european-regional-development-fund-interreg-iic-planarch-project/oclc/314101839&referer=brief_results

 

The former assesses the outcome of the Planarch research and discusses modelling that can be done to find ‘sites’ and understand intervals between (eg Clive Orton’s work 2000).  The 5% figure emerged from Planarch, replacing previously ridiculously  low levels of sampling promulgated by CBI code of practice and very early days ALGAO advice following the advent of PPG16.  Irish road evaluations frequently had 10% evaluations.

 

In Cambs, we don’t use a hard rule for evaluation sampling of development areas, save to say we might use 5% in the absence of other supporting information, by which I mean non-intrusive surveys rather than DBA (unless this aces medieval landscapes and is supported by carto and documentary evidence).

 

Where combined survey and study will be done, we will look to test the results and the blanks between, and also to test topographic anomalies.  This might see an erratic layout of trenching, broader in some areas busier in others.  For large areas we might give a steer along the lines of 3% or 4% evaluation trenching plus 1% contingency trenching for in-field judgemental use.  Or for smaller areas we might require, say, 3-4% plus 30-40m of contingency trenching for judgemental use in the field.  It often depends on what you have on the HER, what the DC experience is in the vicinity of the site, the new survey info, old maps, geology and then your gut instinct (experience).

 

Regarding ‘going in cold’, what we don’t do is to agree any trenching layout until after the prelim work has been done, but contractors/consultants like a steer so that they can cost the scheme for their clients, so we try to oblige with that.

 

Hope that helps.  Might have only taught you to suck eggs – if so, sorry!

 

 

Regards,

Kasia

 

Kasia Gdaniec

Senior Archaeologist

 

Historic Environment Team

Growth & Economy

Cambridgeshire County Council

SH1011 Shire Hall

Cambridge, CB3 0AP

Tel:    01223 728568

Web: www.cambridgeshire.gov.uk/archaeology

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