As we don't have any mains drainage here the only alternative is a sewerage
treatment unit. As you can imagine, one unit to deal with the possibility
of eighteen guests has to be a fair size. The recommended unit was this
one, you can get an idea of the size by the way it dwarfs my truck! So
here we have in excess of five thousand pounds worth of plastic and fibreglass
and the idea is you dig a hole and bury it.
I have dealt with smaller ones of these before and knowing what a
pain they can be I decided to contract the work out. Friday 30th was dig
day and men and machine duly rolled up on site. 
The dig and the installation went like an absolute dream and by 2p.m. I was thinking I could have done this myself and saved a bob or two! The tank was in place spot on level and had six cubic metres (approx. 10 tonne) of concrete around it. I thanked the team and off they went.
One of the things you need to do when burying these units is make sure that the inside of the tank gets filled with water at the same rate the hole around it is filled. This takes a long time with a hosepipe on a unit of this size. So the tap was left running and I went back from time to time to see how it was going.
4p.m. It is now raining and the thawing snow is adding to the amount of water pouring round the outside of the tank. This did not concern me too much as the water on the inside was at least as high so I left the hose pipe running as the tank was still not full.
6p.m.
Went out check the water level and noticed the tank had moved, only slightly
but it had moved. By this time it is pouring down with rain and the snow
is thawing rapidly. Water was gushing into one side of the hole through
what appeared to be a mole hole. I hate to think what happened to the
mole! I managed to plug the hole with clay and reassessed the situation.
The inside was nearly full by this time so I turned off the hose pipe
and checked the tank with my level. Yes it had moved, but was it still
alright?
6:45p.m. After a coffee and far too many cigarettes went out again armed with torch, level, tape measure and Daz (one of my partners in crime) to check just how far out of level it had gone. Unfortunately there was no need for the level and tape measure. The days work had been to waste and there is now far more work involved to put it right.
