I am about to change the silica sand (not DE) in my swimming pool filter. Is there any use that I can make of this in the landscape?

Bill.

I dont know about landscaping, but you can mix it with joint compound and spread it on the walls for a cool stucko look.

How much you have will determine what to do with it but generally you could add it to your compost pile and then evenually it will be put into your soil.

There is about 600 lbs. of old sand. I could put some in the compost, but I remember reading someplace that it should not be used in the garden/yard. Something about this type of silica sand not being helpful to an organic program? The easy thing would be if I could spread it on the yard.

Bill.

The only reason you would not use it in the garden is because of the, potential, high levels of chlorine, or other disinfectant, which really will fairly quickly disipate into the atmosphere since none are very stable. I would spread it around very thinly, not plunk it down in small piles.
What you need to keep in the back of your mind is, is spreading that sand around your yard more organic than sending it to a landfill?

bparker,

Pool-grade diatomaceous earth goes through a process called "calcining", where it's exposed to extreme heat of around 2200degrees F in order to reshape the natural DE to a size suitable for pool filtration purposes. A more significant and potentially harmful result of that process, however, is that the crystalline silica content of the DE is enormously and dangerously increased to toxic, carcinogenic amounts upwards of 60% as compared to food-grade DE of around 1%.

I doubt exposing pool-grade DE (used or otherwise) to the heat of a compost pile would negate the crystalline silica content. Matter of fact, it would almost seem logical that the increased heat might make matters worse. Not sure, but IMO, not worth the chance.

Either way, I think it's unadviseable to use pool-grade DE anywhere in your garden. Especially if you're gardening organically. You wouldn't add any other chemically-treated, highly carcinogenic material to your garden/compost, so IMO, I don't think this is any different.

How about calling the supplier/store where you originaly purchased the DE and ask their opinion or contact your municipal authority. They may have some hazardous waste disposal facility or program that might be of help to you.

the heat of compost pile will not effect the sand at all. since the temps that effect silcon are over 1000 degrees f. gardenz check you facts next time.

gardenz, post your source of information please. I have not seen anything about making DE into a filter media (this is also used in some of your drinking water filters) makes that silica inot a carcinogen, but I do know even the food grade will cause certain cancers of the lungs if you breath it.

In its amorphous (non-formed) state, DE is the "dust" or "powder" safe for horticultural use. Calcining (some refer to it as "sintering") - exposing it to extremely high temperatures - alters its physical structure by forming it into a defined crystal. That "forming" or restructuring increases the crystalline silica content of the DE to carcinogenic proportions. There's no dispute that inhaling even food-grade DE is a danger. But it does not pose the same (or even close to the same) hazard as exposure to calcined DE used in pool filtration. The FDA, CDC, OSHA, EPA and medical sources all agree on this. Crystalline silica content of over 3% is considered over the acceptable food-grade limit and not to be used around, near, or in anything other than that which it is intended. In this case: in a pool filter. Period.

Not to have "crystal" clarity about this on a gardening (organic or otherwise) venue is extremely irresponsible and dangerous for the gardener who is compoletely unfamiliar with any kind of DE, which is the only reason I'm posting this addtional information for the (hopeful) benefit of anyone who may be confused about this or have questions in the future. People should know how pool-filter DE is made; it's carcinogenic capacity; and the reason why it should never - ever - be used in any kind of a garden.

•From: Wikpedia
"The type of hazard posed by inhalation depends on the form of the silica. Crystalline silica poses a serious inhalation hazard because it can cause silicosis and can eventually lead to cancer. Amorphous silica can cause dusty lungs, but does not carry the same degree of risk as crystalline silica. Food-grade diatomite generally contains very low percentages of crystalline silica. Diatomite produced for pool filters is treated with heat, causing the formerly amorphous silicon dioxide to assume its crystalline form. In the United States, the crystalline silica content in the dusts is regulated by the Occupational Safety and Health Administration (OSHA), and there are guidelines for the maximum amounts allowable in the product and in the air near the breathing zone of workers."

•From: www.biconet.com/home/infosheets/DiaEarthPestCtrl.pdf
"Calcined fossils are often sold for use in swimming pool filters. Such material has little absorptive power, andis not useful as an insecticide (see Common Sense Pest Control Quarterly 3(1):14-16). High temperature (800 degree C) also converts amorphous silica into crystalline silica, and some grades of diatomite on the market may contain up to 60% of this material. Crystalline silica, when inhaled can cause the deadly disease silicosis or other respiratory problems (Katz 1991a; Diafil 1992; Abrams 1954) "

•From: Diatomaceous Earth

•From:Canadian Environmental & Health

•From: CDC

•FromThe Dirt Doctor
"Swimming pool or filter DE on the other hand has been calcined (partially melted) and often chemically treated. It is dangerous to breathe because of the high level of crystalline silica and has no use for anything other than in filters."

•From Steve Tvedten of The Biocontrol Network
"Make sure the DE you use meets World Health Organization (WHO) safety standards. WHO cautions that DE with a crystalline silica content over three percent (3%) is dangerous for ingestion by humans or animals. [Safe Solutions, Inc.] DE has less than 1% free silica. Swimming pool DE ranges from 60% to 70% free silica."

**Finally**:
For people who are so concerned about "getting or disputing the facts", I suggest you do the legwork. I'm not the only one who has access to Google. For starters, type in the critera: "carcinogenic calcined diatomaceous earth". If there's any significant disparity in what I've stated or the references I've posted, I'd like to know. If there's any additional information, I'd like to know that, too. I'm never adverse to saying "I don't know", and I'm always interested in learning.

Okay, so the problem is that this pool filter DE is an inhalation hazard, just as the food grade DE is. So the question was would composting the pool filter dregs pose a problem in the soil and the answer is, no. Breathing it would be, but then inhaling manure would also be a problem, so don't inhale any.

My original post was about a "sand" pool filter, not DE. I wonder if the sand goes through a similar transformation process.

Bill.

quote:

Originally posted by bparker:
My original post was about a "sand" pool filter, not DE. I wonder if the sand goes through a similar transformation process.

Bill.

the reason this thread got on subject de is gardenz did not bother to read your thread clear.

quote:

originally posted by KimmSr:Okay, so the problem is that this pool filter DE is an inhalation hazard, just as the food grade DE is. So the question was would composting the pool filter dregs pose a problem in the soil and the answer is, no. Breathing it would be, but then inhaling manure would also be a problem, so don't inhale any.

I was glad to provide some research and references that you were unable to locate which explains the extreme heating (calcining)of DE which does, in fact, create a carcinogenic hazard. Whether inhaled or ingested, it's something I wouldn't want in my compost pile or my garden. Just as I wouldn't want asbestos, another inhaled carcinogenic hazard in my garden either. If you find no problem with that, then that's your prerogative. But, if in the face of the references and research you requested, you conclude that pool-grade DE and food-grade DE pose similar health hazards, then I suggest you are terribly wrong and sincerely hope that conclusion isn't passed along to others for the sake of their health, gardens, children and pets. To state unequivocally that the pool-filter dregs wouldn't pose a problem for the soil is something, I submit, that you don't know for sure. Do you have any research to prove that?

quote:

originally posted by bparker:My original post was about a "sand" pool filter, not DE. I wonder if the sand goes through a similar transformation process.

I apologize for misunderstanding. Sand for pool filters (commonly known as pool-filter silica sand #20) may not pose the same threats as DE. I don't know for sure. But you can certainly research it and perhaps check out the MSDS on your product. A couple of pdf MSDS can be seen on these websites:
http://www.u-s-silica.com/mystic.htmClick on "Products" then "Silica MSDS" from the drop down menu.
http://www.northernfiltermedia.com/products.html

Frankly, I like the first response and suggestion you received from farmhound.

quote:

originally posted by gridgardener:the reason this thread got on subject de is gardenz did not bother to read your thread clear.

Yes and until you have something constructive to contribute...Bite Me.

quote:

Yes and untilyou have something constructive to contribute...Bite Me.

Take you nastiness some where else gardenz aka( ). Since it not my fault you did not read the orginal post clearly since orginal poster specifically stated it was sand not de. As for biting you i do not like Soylent green.

Silica sand poses respiratory dangers and there are warnings for this 'sand' just like DE silica.
Check it out on Google
Sorry gridgardener, gardenz was right to post a warning.