Pond Boss Forums POND CONSTRUCTION Soil questions Soil Cement Liner

I am starting new project in Ash Fork AZ. Soil is volcanic cynder, sand and some fine clay.

I have access to free out of spec. cement that is local.

I am considering lining a 1.5 acre pond with 12 inches of 10-20% cement to soil mixture, hydrating and compacting.

Anyone have any experience with soil cement lined ponds?

Pond wise, I'm limited on knowledge. Sedimentary and environmental impact wise, I can offer some insights:

1. Volcanic cinder, if not compacted properly with at least 6 inches of clay, will leech water from your pond quite quickly. Your location has a low to moderately-low evaporation rate, which will not be too much of a concern as you have to introduce more water to fill your pond on a continual basis.

2. Introduction of clay, although slows down the rate of leeching into the sedimentary layers, increase turbidity and total suspended solids. The pond water will be very cloudy. Just be aware of that.

3. Soil-cement will create porous condition, depending on the binding grade and pre-mix ratio of the cement you're obtaining, since you're only utilizing 10-20% of the cement in ratio to the existing soil at your pond. There WILL be an insufficient amount of sealant to prevent porous conditions. This will allow quite a bit of water loss through leeching.

Geotechs, please, chime in!

I have been lead to believe that the sealing capabilities of soil cement are excellent.

Not true?

"Hydraulic conductivity of as low as 1X10-7 cm/sec has been achieved. Unconfined compressive strengths of more than 800 psi have also been achieved. Hydraulic conductivity and compressive strength of soil cement is dependent on a number of factors including the properties of the soil, mix design, and installation techniques. A summary of soil-cement properties is found in American Concrete Institute’s Report titled State-of-the-Art Report on Soil-Cement ACI 230.1R-90"

It is all fun and games until you do it...

Soil cement is used in the oil business to make drilling locations. It is very hard and works well. Don't know about its water containing properties. A drilling contractor could get you the info.

Soil cement is sometimes used to make a low permeability liner for reservoirs. Given that what you are working with sounds like it is fairly fine grained, I would think you would have a decent chance of achieving low permeability, but your soil will likely require a relatively high cement content.

According to this article, adding flyash or lime to your soil cement may improve your results. Got a cheap source of either of these available locally??

http://stuff.mit.edu/afs/athena/dept/cro...orts/SN2995.pdf

I'll look into it.

My thinking was, since the cement is free (less shipping of course) that I would just increase the cement content and ensure serious vibratory compaction with a sheepsfoot.

Looks like your data on the cement is good Harris. Just to make sure to monitor the pH level from cement does cause problem with your pond. Don't believe anyone that cement is inert, and will not create pH issue.

Listen to HawgTusks. Take a sample of your soil as an experiment before dumping massive amount of cement into your pond for lining. Test it for a first week or two creating a 2'x2' liner condition, by molding a testing pond out of a large plastic bowl. Make sure to know how much cement you use in ratio to lime/filler and your pond's soil. 2 weeks will be your standard leeching testing. Curing of the cement is based on the cement's specs for max results.