Pond Boss Forums POND CONSTRUCTION Soil questions Coal ash for pond sealing?

While discussing my pond dreams with some friends, I was told. Why don't you just use truckloads of ash from the powerplant, it makes great roads.

Does anyone have any information on mixing coal ash with existing soils to better hold water?

Here is a website with plenty of info on it. But to be honest, I do not understand soils well enough to understand if it would work or not. "self cementing class C" is used often...

http://whocares.caer.uky.edu/wasp/AshSymposium/AshLibraryAgenda.asp

This one in particular I find interesting.
http://www.flyash.info/2005/108mac.pdf

NuttyGambler very interesting info. I will look at it some more and try and see what I think. My question so far is what is it chemically. I see some good and some questionable things and a lot of "I don't know either" to think about.

OK you chemists , geologists and engineers out there take a look and put in your 2 cents.

Here was an actual test done as a liner for swine manure in Ohio.

http://www.flyash.info/2001/envben2/74wolfe.pdf

The enviromental gal from the local power plant is spose to call me back. The one good thing about this stuff is it is FREE (less hauling that is).

i dont really know ewest. flyash can also be a product of thermal remediation of contaminated soils, so I would probably want a chemical analysis (tox screen) of it to review before i put it in pond. residual refractory toxic compounds (those highly resistant to heat) would be of concern.

as far as being a sealing agent, i could see it helping to bind soils if blended and compacted well....sounds like it might be a really useful alternative.

Well Sir, the good news is that the introduction of ash has sucessfully sealed your pond.

The bad news is that there is a slight possibility that the ash was contaminated and that there could be some minor effect to wildlife....

I would stay away from fly anywhere near a pond. Its chemistry is varible and it often contains heavy metals as contaminant. It is nothing you want near your pond.

jas, Engineer & Geologist

Well this is a new one for me. Keep us posted on this and thank you.

I've completed remedial investigations for landfills that contained 100% fly ash from coal fired power plants. The leachate and resulting groundwater plume contained several heavy metals including arsenic. The chemistry is controlled by the type of coal and pH buffering capacity of the water, redox, etc. The following is an excerpt from an old report I was able to dig up:

"Statistical data indicates that groundwater at the monofill is impacted by aluminum, antimony, arsenic, boron, calcium, COD, chloride, magnesium, nitrate, nitrite, pH, sodium, specific conductance, sulfate, TDS,TOC, and vanadium. Additional sampling and analyses will be necessary to verify statistically significant exceedances of chromium, copper, nickel, selenium, and zinc."

The question is whether the metal species are soluble/insoluble. They should have chemical data on the material including total metals analyses and leach test results.

The presence of metals does not mean that they will go into solution in your pond water. They may stay bound to the liner material and will most likely be locked in once organic sedimentation occurs. Some may leach out the bottom into groundwater.

If the material does contain elevated metals, there may be implications just bringing it onto your property depending on your state laws. It's possible that the power plant has pre-certified the material with the regulators for placement on clean properties. I'd be cautious any time someone is offering "free" material.

Power plants that burn coal put mercury into the air. So would it be logical to assume the ash could contain mercury? Mercury is a heavy metal.