Irish Industrial Landscapes: Sampling

SASAA advises that  ALL contexts are sampled...

Since excavation is a destructive process there is no reason not to sample. Samples are essential because they allow “the return” to the site after the excavation has been completed and the site backfilled. The samples can always be discarded if no further work is required or if funds prove limited. 

We strongly advise that some soil samples are kept as per individual context/key contexts together with representative material from the site.


No sieving/sorting...

Once sampled, it is important NOT to subject the sample bags to  any sieving (wet or dry), mechanical or by hand prior to ALL specialists having obtained sub-samples of the original context. As industrial waste specialists, we often receive bags containing slag only. There is little that we can deduce about the site from these materials alone, other than the obvious fact, that some metal working was carried out locally!


How much to sample? 

Some contexts can fill multiple 1litre bags, others are hardly enough for a small bag. SASAA generally requires 1L bags for testing & analysis. Since it is almost certain that more than one specialist will be involved, in which case adequate provision should be made for all. Advice from SASAA specialists may be important at this stage - click here to ask the specialist.

Should individual contexts consist of large quantities of metallurgical waste (only) then it is important to remove everything.  It is also important to bag ALL for the purpose of weighing and thus providing a quantitative assessment, in addition to the typological appraisal, of the types and amounts involved.  The case of bloomery iron  making and working at Johnstown I, along the M4-KEK motorway, is an example at hand. 2 metric tonnes of slag were recovered - eventually they had to be re-buried - providing an accurate figure of the amounts generated, rather than an estimated one. 


Sampling in potentially contaminated land...

It is assumed that a contaminated land assessment has been carried out prior to the start of evaluation phase and that archaeological staff are equipped with adequate protective gear. 

For a site assessment on potentially contaminated land, email us at

Click here to find out more about SASAA's Sampling & Recording Consultancy.





Sampling in contaminated land, SASAA images©