1st November 2011, 06:37 PM
I've worked on any number of jobs where trial trenching was frankly unneccessary (the site's going to be developed anyway and it's clear in advance that a substantial archaeological response will be required), and in the event proved to be actually counter-productive, fragmenting the archaeology etc. I've seen any number of eval specs which have specifically stated that feature intersections should be specifically targeted...No! No! No! There's a job in my backlog where a certain Very Large Unit (RAO, shock, horror) did the trial trenching, overmachined all the trenches due to a lack of even remotely local knowledge and destroyed a number of critical intersections which meant that when I came to write up the subsequent area excavation I was unable to phase several critical parts of the site short of making educated guesses based on the geophysics - thanks! And the site-with-the-footprints would have been less of a surprise if another unit (funny, another RAO) back in the 90s had been able to tell the difference between natural and 3ft-plus of stratified RB vicus..... Low feature-visibility in some subsoils (especially gravel on gravel) means that you're going to miss or miss-interpret half the features in a small trench anyway, I've been doing a job this year where you could only see half the features from 20m away in exactly the right light and after just the right amount of rain, so trial trenching would have been completely misleading anyway. Their main value is on deep-strat sites, where they represent sacrificing a percentage of the resource in order to plan digging the rest in a coherent manner (and more critically costing the thing!)