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Re: E-M:/ sludge

Dave and Others,
I don't believe I came out against beneficial reuse of biosolids in a blanket way.  I did point out that these materials are often contaminated with toxic pollutants and that few critical voices have been heard on the issue.  I agree with you about the PCBs if you are speaking in the parts per quadrillion level.  At that concentration, they are likely to occur everywhere.  However, that fact does not provide any sort of reason for further additions of the toxic constituents to the environment, particularly in a manner which does not lend itself to remediation (e.g,. farmlands).  It would be difficult to address the issue of bioaccumulation of PCBs in wildlife after years of sludge amendments once it happens.  Consequently, the precautionary principle seems a useful guide in this matter.
For the Wisconsin sites, a comprehensive pollution prevention analysis should be conducted to detect localized sources of PCB to the waste stream (if there are any).  Truly ambient contamination will show contamination throughout the system.  I also know of no reason to think that Michigan facilities are any different with respect to contamination levels and variability.  In the Wisconsin cases, PCB concentrations are variable across the sites.  If someone is interested in seeing the data, I'd be happy to send an excel file.
There are many good reasons to use sewage sludges as soil amendments, however; and these must be balanced with the drawbacks.  There are uses of land that are compatable with sludge applications.  Soil criteria for toxic pollutants such as PCBs would assist agencies and the public in determining when applications of contaminated biosolids exceed levels of concern. 
There should be a comprehensive set of soil criteria for toxic pollutants commonly found in biosolids, dredged materials and other contaminated aggregates.  They should cover the well-known group of persistent and bioaccumulative toxins including the heavy metals such as mercury.  A process should be developed for establishing criteria for future pollutants of concern. 


Dave Zaber
----- Original Message -----
To: dzaber@chorus.net ; enviro-mich@great-lakes.net
Sent: Monday, February 26, 2001 6:53 AM
Subject: Re: E-M:/ sludge

I hear what you are saying. You are correct in that it could mean there could be more than just background PCB's causing this, however, the opposite could also be true. The background levels can also vary between POTW sources. We cannot automatically say that just because the levels appear to vary between POTW sources, this means we infer that there are more than ambient sources. It sounds like this is a case for additional study. Questions such as how many samples were taken, etc. all come into play. I guess my original argument is that we should not make broad statements against beneficial use of organic sludges for soil amendments. It is a waste of good organic materials. Now, if there is some sort of other hocus pocus going on with more than ambient PCB's et al, or, it is at some greater than regulated amount, then certainly testing or study is indicated, but broad encompassing statements that demand the end to practices based on sound bites of information don't always give the whole picture. 
Another question. When you said  "in Wisconsin, at least, 28 of 48 POTWs sampled did not have detectable PCBs in the sludge.", do you recall what the detection limits were? My comment in the last e mail on ubiquity were based on the parts per quadrillion level. I believe that in those terms it is everywhere.
Best Regards,

>>> "David Zaber" <dzaber@chorus.net> 02/25/01 06:15PM >>>
David and Others,
The problem with the argument that "PCBs are ubiquitous" is that it ignores the fact that in Wisconsin, at least, 28 of 48 POTWs sampled did not have detectable PCBs in the sludge.  Ubiquity of contamination would imply similar levels across all the POTWs (or at least detectable levels).  I don't doubt that some PCB could probably be found in most sludges.  Its just that there is a range of contamination levels across the POTWs  which suggests sources other then ambient for many systems.  I see no reason to believe that Michigan POTW sludges are any different in magnitude or variation of contamination.
Dave Zaber
----- Original Message -----
To: dzaber@chorus.net ; enviro-mich@great-lakes.net ; rbodanyi@umich.edu
Sent: Friday, February 23, 2001 7:45 AM
Subject: Re: E-M:/ sludge

Here's the rub. If you research the subject of PCB's at all. What you will find is that PCB's in our world are now "ubiquitous". That means they are everywhere, literally. They are found, along with a soup of many other chemicals we consider toxic in low concentrations even in areas we consider to be pristine such as arctic wastelands where man has rarely ever set foot, and certainly has never manufactured anything, or lived. Airborne transport has seen to it that our repast has been transported over the entire planet. We live in a closed system. The question is, do we want to lock up the beneficial reuse of sewage sludges, for the low levels of PCB's that are contained in them? We could incinerate all of it I guess, but look at the loss of organics. This will not be able to be replaced. It will however add to the green house effect. Burying it will not help either. 
I guess my question is, I hear lots of bashing going on out there against "beneficial reuse", but what solutions do those bashing it offer in it's place that do not create only other problems?
>>> "David Zaber" <dzaber@chorus.net> 02/22/01 04:39PM >>>
So called "beneficial reuse" of sewage sludges has developed a large and dedicated following amoung POTW operators and regulatory agencies.  Its hard to find many voices against it.  A recent survey by Wisconsin DNR of POTW sludges found PCBs in a significant portion (levels available upon request).  Could Michigan POTWs have the same problem? 

The overapplication and nutrient issues is also clearly important.
Dave Zaber
----- Original Message -----
From: Spartacus
Sent: Thursday, February 22, 2001 11:55 AM
Subject: E-M:/ sludge

Enviro-Mich message from Spartacus <rbodanyi@umich.edu>

Respectfully submitted,
I think it's important to note that even uncontaminated sludge poses
threats to the natural environment when over-applied, as it often is,
because excess nutrient runoff chokes local streams and rivers. This
phenomenon is particularly visible in the case of CAFO lagoon failure, as
happened with the New River in Virginia.

Ryan Bodanyi,
Student, University of Michigan

>Delivered-To: enviro-mich-outgoing@glc.org
>Delivered-To: enviro-mich@great-lakes.net
>Date: Thu, 22 Feb 2001 08:58:44 -0500 (EST)
>From: Karen Griggs <kgriggs@kettering.edu>
>To: joonmck <joonmck@gateway.net>
>Cc: enviro-mich@great-lakes.net
>Subject: E-M:/ sludge
>Organization: Kettering University (formerly GMI E&MI) - Flint MI
>Sender: owner-enviro-mich@great-lakes.net
>Reply-To: Karen Griggs <kgriggs@kettering.edu>
>List-Name: Enviro-Mich
>X-Loop: enviro-mich
>Enviro-Mich message from Karen Griggs <kgriggs@kettering.edu>
>Dear colleagues,
> Not all sludge contains all those chemicals. Land application of treated
>wastewater and sludge are good technologies in harmony with nature,
>provided that industrial pre-treatment has resulted in high quality
>effluent or good sludge that will bio-degrade.
>Karen Griggs
>ENVIRO-MICH:  Internet List and Forum for Michigan Environmental
>and Conservation Issues and Michigan-based Citizen Action.   Archives at
>Postings to:  enviro-mich@great-lakes.net      For info, send email to
>majordomo@great-lakes.net  with a one-line message body of  "info

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