Louisville will sell sewage sludge as fertilizer

[Buzz Clik]

Quoting from the article:

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MSD plan for fertilizer advances
Agency says sludge pellets acceptable risk

http://www.courier-journal.com/localnews/2004/01/27ky/m...

The Metropolitan Sewer District's plan to sell treated sludge for use as a fertilizer has received a big boost from the Kentucky Division of Waste Management, which has found that it does "not pose an unacceptable risk" to people or the environment.

Ronald D. Gruzesky, the division's solid waste branch manager, warned MSD in a letter dated Friday that concentrations of certain hydrocarbon chemicals in the material exceed certain EPA long-term health screening levels. But he wrote that the chemicals would quickly break down when exposed to sunlight and air, and would not pose a problem if applied on lawns and gardens at appropriate rates.

The next step toward commercial sale of the product is approval by the University of Kentucky College of Agriculture's Division of Regulatory Services, which has final say on whether it can be officially sold as a fertilizer — and how it must be labeled.

click link for more

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I'd be interested in knowing what the "hydrocarbon chemicals" were and at what concentrations.

[hatrack]

1. "Certain Hydrocarbon Chemicals" - WTF?!?!?!?

Sure, let's sell the stuff and spread it all around, and talk about "certain hydrocarbon chemicals".

Maybe in a few years we can also talk about "certain hypoxic rivers", "certain seasonal fish kills" and "certain contaminated groundwater sources".

[treepig]

3. the problems you refer to are the result of nitrogen and phospates

not "hydrocarbon chemicals" the "dead zone" in the gulf of mexico, is another example

of course, hydrocarbon chemicals may or may not be dangerous (the devil's in the details). in any event, treated sewage ultimately all released back into the environment now, so making proper use of it can't be worse than what's happening now.

[Buzz Clik]

6. Excellent points.

By marketing the material, the sewage sludge becomes subject to more levels of regulation and oversight. The general public will be better protected in the long run.

Sewage sludge often contains high concentrations of nitrogen and phosphorus, but regulations forbid surface application without incorporation. So, runoff to surface water is drastically reduced.

[mastein]

13. An explanation

Selling this waste is a very common practice across the country, and I suspect the only novel thing about it is the small quantities being sold to individuals and not farms. That said, I agree with the article that hydrocarbons are no worry (if the sampling etc. were done correctly, and I have no reason to think they weren't) as they will literally burn off into the atmosphere creating CO2 and H2O both needed for plant life. THe larger chain hydrocarbons that make up gasoline that burn at higher rates probably are not present at all, or if they are, they are in minute quantities. Overall this is a win-win deal. If you have further questions feel free to contact me off line and I can get into more detailed explanation.

[HereSince1628]

2. Milwaukee did this, the product was called Milorganite

on edit: it appears they still do...for the story:

http://www.milorganite.org/companyinfo/companyhistory.a...

[soothsayer]

4. and people wonder how folks got sick at Chi-Chis's green onions

Or how you can get sick off of cantalopes (which unlike honeydew melons, are allowed to be fertilized with human waste). We can look forward to more of this.

Disgusting.

[Buzz Clik]

5. Untreated versus treated waste

The problem associated with imported green veggies comes from the application of uncomposted/undigested, untreated waste directly to the plants. Neglecting to wash the products before use contributed as well.

Land applied sewage sludge in the U.S. is covered by very specific regulations includes pathogens and vectors. There is no similarity between the Louisville pelletized material and the liquid ca-ca sprayed on the plants in Central and South America.

[Flightful]

7. Toronto tried making those pellets

They blowed up real good.

[kimchi]

8. I just don't get it.

My friend lives on 1,000 acres used to raise cattle. Recently they started putting human sludge on the land to fertilize it--including toilet paper-which makes it look like there was a dusting of snow.

I'm just amazed that pig shit (long used as fertilizer) is held in giant pools, while human waste goes on our land. It's exactly bass-ackwards.

We are still waiting to see if the owner tries to sell his beef as "organic, free range" or not.

[hatrack]

9. Oh, then you'll be glad to hear this

Among the new post-mad cow USDA rules announced yesterday was one which forbids cattle feed companies from mixing chicken manure with their cattle feed.

Bon appetit!

[Buzz Clik]

11. Toilet paper?

I'm not sure I understand how sewage sludge from a municipal solid waste plant could contain recognizable toilet paper. Quite literally, there is no way that stuff would pass muster under federal and state guidelines.

A lot of people are getting concerned about the tremendous amount of waste accumulating in ponds from confined animal feeding operations. Too many animals in too small an area. There is movement afoot to force these operations to install waste water treatment plants similar to those used by municipalities. That would solve many problems.

[NNadir]

10. I have no problem with this at all.

I am genetically well disposed to "waste into commodity" thinking.

I have no idea what hydrocarbons they are talking about, but I note that many hydrocarbons are naturally occuring compounds. Methane (farts) is the simplest hydrocarbon, and all fats are hydrocarbons.

The chemistry of all existing foods can be presented in such a way as to make it scary in any case. Risk is the least understood scientific concept among the American population as a whole. Unless someone can demonstrate huge harm, this is an excellent way to recover the fixed nitrogen and phosphorous that now flows into bodies of water and contaminates them. It will reduce the amount of these materials that is produced to spread on fields.

As for the "Chi-Chi's" outbreak; that was the result of a contaminated washing pump. It had nothing to do at all with fertilizers.

As I've stated here many times before, I believe that sewage has an enormous future value in the energy business as a source of water with a high carbon content for supercritical oxidations.

[jmcgowanjm]

12. ArkansasOklahoma Illinois River dispute

Arkansas has a pop. of less than 3M. If you include
farm animals it's 22M+.

In Arkansas the Illinois is just one more pretty river.
In Oklahoma it's one of their few Scenic Rivers.
The Illinois runs from AR into OK.

The 2 just finished a landmark agreement on
phosphorous content. When you see green slime
in/on water, it's caused by phosphorous.

But then Arkansas just days ago,put off implementing
the poultry litter handling safeguards.
I don't know Oklahoma's reaction. Any Tulsa
DU'ers out there?

[earthman dave]

14. Heavy metals and other industrial waste

A lot of chemicals and heavy metals get flushed in large metropolitan areas, AFAIK. This was the "title story" for the book "Toxic sludge is good for you!", by the guys who run www.prwatch.org - well worth a read.

[NNadir]

15. It is easy to monitor heavy metals, and set specifications.

It is of course now illegal to discharge heavy metals into sewage systems in most cities.

Before I address the title of the post, I have an interesting aside. In some places, the ban on heavy metal contamination has a curious effect, inasmuch as it has lead to increased corrosion of septic systems. This is because heavy metals form insoluble sulfides. One of the chief compounds found in sewage, accounting for some of the noxious odor is hydrogen sulfide formed from the biodegradation of the amino acids methionine and cysteine in proteins. In the past, this hydrogen sulfide would react with heavy metal contaminants in the sewage to form heavy metal sulfides, such a mercuric sulfide, lead sulfide and iron sulfide. This had the happy effect of rendering the heavy metals insoluble and removing the hydrogen sulfide. When the dumping of heavy metals into sewage lines was forbidden, the quantity of hydrogen sulfide went up. In the presence of oxygen, hydrogen sulfide is oxidized to sulfuric acid. Sulfuric acid in turn decomposes concrete (as in acid rain). Concrete is used to make sewage pipes. The overall result is to cause increased corrosion of sewer lines.

Common heavy metals that remain in sewage today are copper (from oxidation of water pipes that bring water into homes, silver (from sodder) and unfortunately lead (also from sodder, especially in older homes). All of these elements are found in trace quantities in homes with soddered copper plumbing in the drinking water. Additional quantities of lead occur in sewage from waste lines, especially toilet bowl seals, which are also made of lead. It is fortunate that lead forms a very insoluble sulfide, PbS, the chief constituent of the widely distributed ore known as galena. (The city of Galena, Illinois, I believe is named for this compound.)

Silver forms an insoluble chloride and it hardly ever finds its way into the food chain. Copper sulfide is also insoluble (it is the form of many copper ores.) This is unfortunate in a way, since copper, although it can be toxic at high levels, is an essential element: It is a constituent of important proteins involved in oxidative phosphorylation, a key reaction on which all eucaryotic life, including human beings, depend. (A high concentrations however copper can compete with iron in certain heme containing proteins, of which hemaglobin is just one.)

In any case the concentrations of lead are extremely small in most sewage, and what is there is at best of very low solubility owing to the presence of hydrogen sulfide. I don't really believe that much of this lead will find its way into the foodchain, something that is easily verifiable by chemical analysis.

If it can be shown, however that the quantities of lead (or any other element) found in sewage sludge do in fact find their way into the food chain, especially via a mechanism by which it is concentrated, it is a realitively simple affair to set specifications for heavy metal contamination. One can then ban lots exceeding this specification. This is exactly what is done for all industrial materials, be they chemicals, fertilizers, or foodstuffs.

This of course begs the question. If you ban using all sewage sludge from use, what exactly do you do with it? I think a law against the use of toilets would attract many violators.

[mastein]

16. Ok, I am amazed

Wow, a chemist that understands tox and biochemistry!!! Can I refer people who have water questions for me to you. That is the best explanation behind SDWA and CWA I have seen, anywhere. Matt

[mn9driver]

17. My Dad used to buy this stuff for our garden back home.

We'd take the truck down to the treatment plant and shovel in a yard or two. Back then, it wasn't pelletized but it was totally composted-it had a really distinct smell-you never would forget it-but not a human waste type of smell.

It made great fertilizer; there were a few years when I'll bet 25 percent of my caloric intake was (indirectly) attributable to "sludge".