Yes that can work. It may be that the prior application of
bentonite or time or the alum/colloidal clay mix are forming a seal. See below from prior posts on the subject. This is a good place to start an archive on leaking.
http://www.pondboss.com/forums/ubbthread...=true#Post78440We need to get George and DIED in on this as they can explain permeability and porosity of soils and rocks.
Porosity is indirectly related to hydraulic conductivity; for two similar sandy aquifers, the one with a higher porosity will typically have a higher hydraulic conductivity (more open area for the flow of water), but there are many complications to this relationship. Clays, which typically have very low hydraulic conductivity also have very high porosities (due to the structured nature of clay minerals), which means clays can hold a large volume of water per volume of bulk material, but they do not release water very quickly.
Sorting and porosity
Effects of sorting on alluvial porosity
Well sorted (grains of approximately all one size) materials have higher porosity than similarly sized poorly sorted materials (where smaller particles fill the gaps between larger particles). The graphic illustrates how some smaller grains can effectively fill the pores (where all water flow takes place), drastically reducing porosity and hydraulic conductivity, while only being a small fraction of the total volume of the material.
In the earth sciences, permeability (commonly symbolized as κ, or k) is a measure of the ability of a material (typically, a rock or unconsolidated material) to transmit fluids. It is of great importance in determining the flow characteristics of hydrocarbons in oil and gas reservoirs, and of groundwater in aquifers.
The intrinsic permeability of any porous material is:
κI = C X d2
where
κI is the intrinsic permeability [L2]
C is a dimensionless constant that is related to the configuration of the flow-paths
d is the average, or effective pore diameter [L]
] Yes many rocks(not talking about gravel or broken or fractured ones but solid rock layers) can have fluids run through them under pressure. Also clay when dry absorbs water and expands until water will no longer be absorbed and it creates a seal subject to pressure. Porosity is the space between grains of soil or rock and fluid will flow through them limited by force needed to get the fluid through the pore space.
Now George or DIED can fix what I poorly explained.
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thanks for calling out for the geo's ewest, but you did a fine job. an unintuitive physical property of clays is their high porosity and capacity to store water...well put....yet at the same time, their extremely low permeability limits the movement of that water....hydraulic conductivity (K) is basically the rate or speed at which water (or any fluid) can move through a particular media. Bill is correct in that all soils leak, its just a matter of how fast.
I apologize if I offend anyone with the following simple science, but it helps me to put things in terms that even my mosquito fish can understand. ewest hit all the important points about stuff moving through other stuff....in relation to permeability, porosity, conductivity, tortuosity (the flow paths), but for me all other things being equal, and envisioning leaky ponds i think primarily about how fast the water moves through whatever type of soil. So here are some example ranges of K (hydraulic conductivity) for different soil types just for comparisons sake......K is also given in metric units (i.e. cm/s or m/s) but my mind still thinks in inches and feet so I use gallons per day per square foot………..
Gravel : 10E4 to 10E6 gallons/day/ft2 (10E4 is scientific notation for 10 to the 4th power which is 10x10x10x10 = 10,000 - which means between 10,000 to over 1,000,000 gallons of water can pass through a square foot of gravel in one day!!)
Silty Sand to Clean Sand : 1 - 10E3 gal/day/ft2 (10E3 = 1000 gallons = gushing pond leakage)
Silts : 10E-2 to 1 gal/day/ft2 (which means 0.01 to 1 gallon of water can pass through a square foot of pure silt in one day, if multiplied by square footage of pond = very leaky pond…..you can see where we’re headed for clay….)
Clay : 10E-4 to10E-6 gal/day/ft2 (which means 0.0001 to 0.000001 gallons of water through the square foot of clay which equates to a leaky pond only on geologic time, this is a good tight pond seal).
this thread is a classic for leaky ponds containing many great insights, speculations, and statements above (theo, bill, brettski, eddie, ML...all yous guys), but IMHO to really help DonB we need to hear back from him about his construction techniques to help determine whether its just absorption into new pond lining or an actual seep. Hope the explanation on conductivity helps a few of you lurking get a feeling for why clay works so good.
My personal situation prior to renovation was hydraulic driven seepage through bedrock on pond side of dam, with water daylighting in creek below dam. In brief, this was mostly remedied by a lot of digging, cleaning, grooming and installing a well compacted mixed native and imported clay liner within deepest areas of pond subject to the greatest hydraulic pressure.
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Robinson I think you have described sorting. Different types of dirt have different grain sizes. When they are mixed and wet they exhibit sorting. I should have taken time to post the pic with the first post.
Well sorted (grains of approximately all one size) materials have higher porosity than similarly sized poorly sorted materials (where smaller particles fill the gaps between larger particles). The graphic illustrates how some smaller grains can effectively fill the pores (where all water flow takes place), drastically reducing porosity and hydraulic conductivity, while only being a small fraction of the total volume of the material.
http://en.wikipedia.org/wiki/Porosity When dry clay is mixed with other dirt the aggregate has grains of different sizes. Water flows through the pore spaces between the grains not the dirt. When the mixture gets wet the grain size of the clay increases (swells as it absorbs water)reducing the pore space volume and the smaller other dirt grains sort to clog the remaining pore spaces to form a seal. Compaction helps because it binds the grains and reduces the pore spaces.
The water in a new/renovated pond may look like it is leaking for a while as its clay/soil mix absorbs water reducing pore space and goes through sorting and sealing. Once that process finishes it should be sealed and not lose water except through evaporation (unless there is a real leak ).
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I hope your pond camera has done its job. On your question about pond dam leaks we fixed a similar problem with drilling mud.It comes in sacks and is dry
bentonite clay.It was called aqua-gel. We had a sand that was leaking into the dam at the bottom. We used 5 or 6 sacks on a 5 acre pond.The clay powder when wet did not cloud the water as it sank toward the bottom and toward the leak. In about a week the clay had been pulled to the leak and mixed with and covered over the sand. Good luck and report your results.
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Theo , Leaky & scsims :
I will try to get this right. Theo I did see the reference to barite . That is why I used your post reference. Thanks for the info. I think you are right about it being in that post because of livestock {the website references it as part of the goat research extension}. I don't think that matters though it will flat stop leaks.
Barite and
bentonite are both used in oil well drilling mud . The mud is used to stop the water based drilling fluid from going into the formations drilled through ,to lub the hole and return drill cuttings to the surface and to hold back the pressures encountered. All of this happens under pressures from 50psi to 25000psi.
Drilling mud comes dry in sacks and is mixed on location into mud pumps. If the job requires greater mud weight or more leak stopping ability barite is added.
I am not a chemist or drilling endg. so I don't know about its fert. ability. I know barite is a sulfate BaSO4 so no nit. or phos. as in most fert.
I once had a pond that leaked badly because of sands in the bottom at the dam. My dad, a geologist got a few bags of drilling mud and barite . We mixed the two with water to form a thick mud liquid { like thick milk} . Then we took a length of 6in pvc pipe with a one way valve {outflow only}. Put the pipe in the water with the valve end near the bottom where it met the dam. Then poured the mud in the pipe. Moved around to several places along the dam and repeated. In about 2 weeks no more leaks. Has not leaked in 20+ years and no apparent effects on the pond ecosystem.
Will this work for Leaky and scsims. I don't know but there are lots of pond dam specialists who could tell us. I note that the ad in Pondboss for a company that stops leaks has a picture of its equipment and it looks a lot like a mud pump system. This post is way to long but I hope it helps. I would hate for anyone to jump off their dam.
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