Holdfast Training Services Trial Blog

This week has seen a number of changes, specifically with the sub-contractor, a number of new black hats have been handed out (the mark of a supervisor on our site), civilians don’t seem to get the phrase ‘You’ve changed!’

Artesian water continues to flow, sometimes I feel like we’re de-watering Southampton, without the help of a pump.  The visit from our geotechnical expert was pretty unsuccessful, in truth he was an environmental expert that was going back to report on what he had seen to his geotechnical experts.  The geotechnical experts have said ‘You’re F*$!ed’ clearly I’m paraphrasing, the best solution that has been suggested is to try and over bore, or encapsulate the former borehole location with a hollow casing allowing it to find a level and then backfilling with a tremie pipe using a grout, they are fairly non-committal on the possible success rates of such an undertaking and there will be a significant cost associated with getting something done and getting a specialist to deal with it.  This would be all very well and good to try except for a couple of problems:

1.  We don’t really have time to experiment, this is now holding up the build, I find this situation pretty frustrating because everyone seems to have ignored it for quite sometime now.

2.  The attempt to cap the water with the concrete plug means that to execute this plan would require breaking out of about 6 m^3 of C50 concrete, so we’re going to get hammered for dayworks.

This leaves us with the french drain option, drawing the water off to a point where it can be collected and enter the drain system, the Environment Agency don’t seem too worried about the situation but winning over Southern Water might be a harder sell.  A conversation with the Great Orator has helped, but in reality nobody can be sure of what may happen.  I’ve done a bit of research and the waterproof joints that have been put in use a product that’s certified for 80m, we’re only talking 3m on my site and therefore it should shrug it off as long as the workmanship is up to scratch.

Such a seemingly simple problem has become quite a big issue, it is made so much worse considering the option to cap the piezo on the first place was offered up for a mere £600 per borehole, I would say we’ve easily spent that in fuel to run the pump.  I think next week will see an attempt at the french drain option attempted, perhaps we’ll pull it off.