Soakaway test & other Goe' survey surprises

[mvincentd]

So I have to do a soakaway test which involves excavating a 300mm x 1m x 2m trench and QUICKLY filling it with 600l of water, 3 times over, so I need 1800l of water.

 

Standard advice is hire a water truck......costs 500 times the price of the water it contains!!! I simply cannot bring myself to pour that away! Anyone done this with a cunning heath robinson alternative?

 

I've 2 ideas; buying an 8' diameter 30" deep paddling pool, putting my wetsuit and goggles on,getting in and leaning on the edge to create a spout. The elf & safety department though fears i'll get carried with the water head first into the 300mm wide hole and get stuck. The serious option I was thinking is 2 x IBC's with the larger 4" outflows and some drainpipe to direct it.

 

The next interesting spec on my SE's survey request is windowless boreholes to 5m.  He knows it'll be chalk.  3 out of 4 Surveyors quote as requested no questions raised.  The 4th says the percussive nature of those boreholes will muller the chalk making it impossible to classify...therefore rotary coring is the option, at around 3.5 x the price.  Do I suggest to my SE his spec might be wrong and volunteer to pay £5k, or be quiet and let it go at his original spec for £1.5k.....I feel as soon as i say something he'll arse cover and jump onto the expensive option.  The entire survey seems a near futile exercise anyway as there's huge confidence its chalk all the way and the only real risk is voids which the boreholes won't reliably identify anyhow.  I currently feel like spending any money on a survey is little more than an exercise in humouring the SE.  Happy to be put straight on that view?  

[Temp]

An IBC holds 1000L and second hand ones cost between £20 and £60.

 

http://www.ebay.co.uk/itm/IBC-1000-Litre-Water-Storage-Tank-Plastic/182374963189?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D38661%26meid%3D49b083dba5ed4d8c8327ada4292477c2%26pid%3D100005%26rk%3D3%26rkt%3D6%26sd%3D182353846753

 

http://www.ebay.co.uk/itm/ibc-/182353846753?hash=item2a7522e1e1:g:vrwAAOSwi0RX0YM2

 

However check what they have been used for.  We got one for my wife's allotment. It was last used to hold shampoo and cleaning it out produced a nice lot of foam.
 

PS: It cost me more to hire a van to go and collect it.

 

Edited December 7, 2016 by Temp

[ProDave]

Are you sure you have your hole size correct?

 

I thought you dug a 1 metre cube hole (1M by 1M by 1M) and then in the bottom of that dig a 300mm cube hole and it was that smaller hole you fill with water and measure the tiome it takes to go down from 75% full do 25% full.

 

Is the English test procedure different to the Scottish procedure?
 

[Gone West]

Is this soakaway for surface water or foul water? It makes a difference. Link gives percolation test details.

 

http://www.wte-ltd.co.uk/percolation_test.html

[Ferdinand]

4 hours ago, Temp said:

An IBC holds 1000L and second hand ones cost between £20 and £60.

 

http://www.ebay.co.uk/itm/IBC-1000-Litre-Water-Storage-Tank-Plastic/182374963189?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D38661%26meid%3D49b083dba5ed4d8c8327ada4292477c2%26pid%3D100005%26rk%3D3%26rkt%3D6%26sd%3D182353846753

 

http://www.ebay.co.uk/itm/ibc-/182353846753?hash=item2a7522e1e1:g:vrwAAOSwi0RX0YM2

 

However check what they have been used for.  We got one for my wife's allotment. It was last used to hold shampoo and cleaning it out produced a nice lot of foam.
 

PS: It cost me more to hire a van to go and collect it.

 

 

The other way to rapidly fill your hole would be to dig it, line it eg with tarpaulin, fill it, then remove the tarpaulin (probably need a winch or tow it away with a car).

 

Can't see how that would work 3 times on the same hole though :-) . Probably 3 IBCs prepared with 3" bungs would be better.

 

Rather like one rapid way to unload a lorry is lots of people or a crane, and the other is to tie the load to a tree and drive away. It all depends on the nature of your load - my dad did the latter with the 2" thick marble top from a butcher's counter mother managed to snag while passing in our small van one day.

 

Ferdinand

Edited December 7, 2016 by Ferdinand

[ProDave]

27 minutes ago, PeterStarck said:

Is this soakaway for surface water or foul water? It makes a difference. Link gives percolation test details.

 

http://www.wte-ltd.co.uk/percolation_test.html

"A percolation test hole 300mm x 300mm x 300mm deep should be excavated below the proposed invert level of the effluent distribution pipe. For most sewage treatment units this depth is from 700mm down to 1 metre, i.e the base of the percolation test hole below is 1 metre below ground. This usually requires a large hole to be dug to stand in whilst digging the small percolation test hole."

 

 

As I thought, you only have to fill a 300mm cube hole = 27 litres of water.
 

[Guest Alphonsox]

Must admit I have never heard of that requirement/test before - We did the percolation test as described by Dave and Peter above. The builders doing the ground works couldn't stop laughing (it was snowing!) - they had never seen anyone actually do the test before. Apparently local procedure is to fill the form in with the numbers you need to get a pass and assume no-one will ever check.

[ToughButterCup]

Just now, Alphonsox said:

[...] Apparently local procedure is to fill the form in with the numbers you need to get a pass and assume no-one will ever check.

 

They don't according to local lore. 

But  knowing my luck.....

[joe90]

9 minutes ago, Alphonsox said:

Apparently local procedure is to fill the form in with the numbers you need to get a pass and assume no-one will ever check.

 

This is is what my planning consultant did and she was ex local authority?

[mvincentd]

Ok, thanks all...though now I am confused.  Seems i need to check the hole size with the geologist.  Its for a surface water soakaway but the test cited at the following link certainly wouldn't require a water truck!

 

http://www.pavingexpert.com/drain08.html

 

 

[Gone West]

10 hours ago, mvincentd said:

Its for a surface water soakaway...

 

 

 

"There are two very different types of soakaway – foul water soakaways and surface water soakaways. Foul water soakaways deal with small volumes over a long period, whereas the rainwater soakaway may have to handle large volumes in a short time. ( A typical test for a surface water soakaway would be a pit 1000 x 1000 x 2000mm filled to the brim and the level recorded at various times until the pit is empty.) "