5th June 2006, 06:46 PM
I have a lot of experience of SMA (or whatever you call it - it has several names), and I reckon it is a good method in certain circumstances, but could be disastrous in some others.
Essentially, it can be very good if you are dealing with low-density remains, with poorly-defined limits, over a large area that is going to be completely stripped anyway. I would not apply SMA in smaller or otherwise more constrained sites, or where I have reason to think that higher-density remains are present, or where there is the potential for a decision to preserve in situ.
Such remains are difficult to evaluate effectively by trenching, even with prior geophysical survey. You can easily get a 'false negative', leading to a decision that no excavation is necessary (or much less than is really needed).
What you do need to do is structure the brief very carefully and in a staged manner that allows for decision-making at key stages on the basis of archaeological issues rather than cost. What I tend to do is specify methods for the stages, with rates per stage.
Pricing is the difficult bit. Generally I ask for a price for the initial strip and plan, because here the quantity is known. We don't know in advance what the quantity is for detailed investigation, so I ask for a rate per square metre. To allow calculation of a tender price, I include a provisional quantity (e.g. 40% of the stripped are to be subject to detailed excavation). The beauty of a provisional quantity in a bill of quantities is that you know it is notional - you will get paid for the amount actually excavated, whether that is 10%, 40% or 80%. Clients understand this.
1man1desk
to let, fully furnished
Essentially, it can be very good if you are dealing with low-density remains, with poorly-defined limits, over a large area that is going to be completely stripped anyway. I would not apply SMA in smaller or otherwise more constrained sites, or where I have reason to think that higher-density remains are present, or where there is the potential for a decision to preserve in situ.
Such remains are difficult to evaluate effectively by trenching, even with prior geophysical survey. You can easily get a 'false negative', leading to a decision that no excavation is necessary (or much less than is really needed).
What you do need to do is structure the brief very carefully and in a staged manner that allows for decision-making at key stages on the basis of archaeological issues rather than cost. What I tend to do is specify methods for the stages, with rates per stage.
Pricing is the difficult bit. Generally I ask for a price for the initial strip and plan, because here the quantity is known. We don't know in advance what the quantity is for detailed investigation, so I ask for a rate per square metre. To allow calculation of a tender price, I include a provisional quantity (e.g. 40% of the stripped are to be subject to detailed excavation). The beauty of a provisional quantity in a bill of quantities is that you know it is notional - you will get paid for the amount actually excavated, whether that is 10%, 40% or 80%. Clients understand this.
1man1desk
to let, fully furnished