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usmcr 
Group: Members
Posts: 922
Joined: Sep. 2003
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Posted on: Mar. 12 2004,10:28 pm |
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It would be interesting to know just how many pepole in our fair city know what sludge is & it's ingredients? In the goverments great wisdom it has been reclassified as a fertilizer even thou it had previously been classified as a pollutant! This so called fertilizer has been & will be spread onto farmers feilds. I will not go into details regarding this topic, instead i will direct you to a site with tons of information about Sludge.
http://www.ejnet.org/sludge/index.html
It would seem to be a pretty high price tag in the sum of $400,000 for the city to pay for a problem that was sapposedly fixed! Someone is dumping a lot of pollutant into the sewer!  This problem is not unique to A.L. but to all cities. There in lies the problem, which the goverment solved by reclassifing sludge as a fertilizer!
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"Do not confuse dissent with disloyalty" Edward R Murrow
Memento homo quia pulvis es, et in pulverem veverteris
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cwolff
Group: Members
Posts: 265
Joined: Aug. 2003
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Posted on: Mar. 19 2004,5:16 pm |
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SLUDGE
The HarperCollins Dictionary of Environmental Science defines sludge as a viscous, semisolid mixture of bacteria- and virus-laden organic matter, toxic metals, synthetic organic chemicals, and settled solids removed from domestic and industrial waste water at a sewage treatment plant. Over 100,000 toxic substances and chemical compounds can be found in sewage sludge, and scientists are developing 700 to 1,000 new chemicals per year. Stephen Lester of the Citizens Clearinghouse for Hazardous Wastes has compiled information from researchers at Cornell University and the American Society of Civil Engineers showing that sludge typically contains the following toxins:
1) Polychlorinated Biphenyls (PCBs);
2) Chlorinated pesticides -DDT, dieldrin, aldrin, endrin, chlordane, heptachlor, lindane, mirex, kepone, 2,4,5-T,
2,4D;
3) Chlorinated compounds such as dioxins;
4)Polynuclear aromatic hydrocarbons;
5) Heavy metals -arsenic, cadmium, chromium, lead, mercury;
6)Bacteria, viruses, protozoa, parasitic worms, fungi; and
7) Miscellaneous -asbestos, petroleum products, industrial solvents.
Federal Clean Water Act defines sewage sludge as a "pollutant.”
The EPA acknowledges that the pollutants and pathogenic organisms in sewage sludge . . . upon exposure, ingestion, inhalation, or assimilation into an organisms either directly from the environment or indirectly by ingestion through the food chain, could, on the basis of information available to the Administrator of EPA, cause death, disease, behavioral abnormalities, cancer, genetic mutations, physiological malfunctions (including malfunction in reproduction), or physical deformations in either organisms or offspring of the organisms.
Today there are about 16,000 publicly-owned wastewater treatment works in the United States, discharging approximately 26 billion gallons per day of treated wastewater into lakes, streams and waterways. Before treatment, this wastewater contains over a million pounds of hazardous components. Sewage plants use heat, chemicals and bacterial treatments to detoxify 42 percent of these components through biodegradation. Another 25 percent escapes into the atmosphere, and 19 percent is discharged into lakes and streams. The remaining 14 percent -- approximately 28 million pounds per year -- winds up in sewage sludge.
The composition of sludge changes as often as materials are flushed into the system. On any given day, according to Cornell University and the American Society of Civil Engineers, Polychlorinated Biphenyls (PCBs); chlorinated pesticides such as DDT, aldrin, endrin, chlordane, and 2,4-D; heavy metals from wood preservatives, pesticides, metal plating, and batteries; bacteria; viruses; fungi; chlorinated compounds; flame retardants (asbestos); petroleum products; industrial solvents; nitrogen; phosphorous; potassium; and dioxin can be found in sewage sludge. These substances can be highly disruptive to life, resulting in reproductive problems, disease, and death.
The viruses, bacteria, protozoa, fungi and intestinal worms present in sewage and sludge is mindboggling. Many of the pathogens cause diseases that sicken, cripple and kill humans including salmonella shigella, campylobacter, e-coli, enteroviruses (which cause paralysis, meningitis, fever, respiratory illness, diarrhea, encephalitis; giardia, cryptosporidium, roundworm, hookworm, and tapeworm. Sludge pathogens can move through many environmental pathways -- direct contact with sludge, evaporation and inhalation, contaminated groundwater, contamination of rodents burrowing in sludge, and uptake through the roots of crops.
Dr. Stanford Tackett, a chemist and expert on lead contamination, became alarmed about sludge on the basis of its lead content alone. "The use of sewage sludge as a fertilizer poses a more significant lead threat to the land than did the use of leaded gasoline," he says. "All sewage sludges contain elevated concentrations of lead due to the nature of the treatment process. Lead is a highly toxic and cumulative poison. Lead poisoning can cause severe mental retardation or death. It is now known that lead interferes with the blood-forming process, vitamin D metabolism, kidney function, and the neurological process. From the standpoint of lead alone, sludge is `safe' only if you are willing to accept a lowered IQ for the young children living in the sludge area.
New York has an especially messy history of waste disposal problems. In addition to sewage, the city used to dump its garbage into the ocean, and is famous for the 1987 "garbage barge" that was forced to sail for nearly 3,000 miles in search of a place to dump its cargo. New York's practice of dumping sludge into the ocean first came under fire from the EPA in 1981, prompting the city to file a lawsuit arguing that ocean dumping was environmentally preferable to land-based alternatives. In 1985, however, the EPA found that New York's ocean dumping site, located 12 miles offshore, had suffered heavy degradation, including bacterial contamination of shellfish, elevated levels of toxic metals, and accumulations of metals and toxic chemicals in fish. Federal legislation in 1987 forced New York to close the 12-mile site and begin dumping at a new site 106 miles from shore. Shortly afterwards, fishermen near the 106-mile site began to complain of decreased catches and diseased fish. In 1988, Congress passed the Ocean Dumping Reform Act, requiring a complete end to ocean dumping by June 1991 and imposing fines of up to $500,000 per day if New York failed to comply.
In 1992 the EPA modified its "Part 503" technical standards, which regulate sludge application on farmlands. The new regulations used the term "biosolids" for the first time, and sludge which was previously designated as hazardous waste was reclassified as "Class A" fertilizer. The beneficial sludge use policy simply changed the name from sludge to fertilizer, and the regulation changed the character of sludge from polluted to clean so it could be recycled with a minimum of public resistance. Sludge that was too contaminated to be placed in a strictly controlled sanitary landfill was promoted as a safe fertilizer and dumped on farmland without anyone having any responsibility.
The 503s regulate 10 heavy metals, pathogen (disease causing organisms) levels, reporting, record keeping, application, management and general requirements. Dioxins and most of the 700 to 1,000 new chemicals added annually to the 60,000 chemicals currently used in US industry are not regulated. The rules are "self-implementing" and any testing that is done, is done by sludge producers themselves.
A recent publication from Cornell University's extension service recommends that farmers "limit the total cumulative load of metals in soil to no more than 1/10 the cumulative loading limits set under federal 503 regulations." Why? Because some heavy metals and excesses of others ingested by aquatic organisms, wildlife, and humans can cause physiological mayhem; troubles like kidney disease, hypertension, liver damage, neural damage, structural change in tissues, and reproductive problems. On average, the 503 regulations for cumulative loading of heavy metals are eight times higher than those set in Denmark, Canada, the European Economic Community, France, and the Netherlands.
Why the discrepancy? Europe uses "non-degradation standards" aimed at preserving farmland free from contamination for future generations. The EPA uses "risk assessments," which seem to have floating benchmarks, a high tolerance for risk, and no consideration for the synergistic effect of the chemicals regulated and unregulated in municipal sewage sludge (combined, some chemicals are much more dangerous than they are as individual substances).
Nitrogen is the main nutrient promoted to farmers as the "free fertilizer" in sludge. Most of the nitrogen in excreta derives from the urine, and the forms of nitrogen in urine are highly soluble and, once mixed with water, are not easily removed from it. Therefore, sewage treatment processes allow most of the nitrogen to remain in the wastewater, transferring correspondingly little to the sludge. Since the concentrations of nitrogen are so relatively low, and the concentrations of heavy metals (e.g., lead, cadmium, zinc, copper, mercury, chromium, and arsenic) are, relative to ambient levels in soils, so high, it follows that massive quantities of sludge must be spread on farmland to attain the levels of nitrogen needed to act as fertilizer. This means heavy metals will accumulate in the soil. Or they will move. Where? Into bacteria, into plants, into the chain of life.
The offers of free lime, besides serving as an inducement to farmers to accept sludge on their land, serves another purpose. The regulations governing land application of sludge require the maintenance of a pH above 6.5 in soils on which sludge is spread. This 6.5 pH is needed in order to bind up the heavy metals--precisely to prevent them from moving--either up, causing "bio-accumulation" in life chains, or down, causing pollution of groundwater. There is an active debate between soil scientists and advocates of land application about this effort to "bind up" the heavy metals. This debate has two questions: whether or not liming works on all the metals from a strictly chemical point of view, and whether or not it matters if it works, since the monitoring and enforcement of pH levels on farms is a virtual impossibility.
There are many problems surrounded by intense controversy over the issue of land application of sludge. Its noxious odor is the first to be complained of, if the least threatening to life. Disease--from viability and regrowth of human pathogens in raw sludge, and other diseases caused by the sludge composting processes--is of major concern to many. But, serious as these concerns are, serious as is the danger of heavy metals' toxicity due to land application, sludge has another yet more threatening characteristic. Far more dangerous to all life is the fact that combinations of some chemicals can cause levels of life process disruptions many times in excess of the effects of any chemical alone. For example, recent research has demonstrated dramatic increases in the estrogenic effects of common pesticides when they act in combination. Whereas the endocrine disrupting effect is 1:1 in the case of the doubling of one single compound, where two or more are combined, their destructive effects are not just doubled but, rather, multiplied and magnified to the order of 600 or even 1600 times. Sludge provides perfectly the conditions for combinations of thousands of chemicals to cause a cataclysmic devastation of life (Colborn et al. 1993; Arnold et al. 1996).
WHAT TO DO WITH SLUDGE?
Ocean disposal of sewage sludge -- sludge which had just been removed from water -- was, in coastal cities of the U.S., standard practice until 1992. Though clearly unsustainable, it was nevertheless only after strong public protest that the U.S. Congress passed a law in 1988 (to be effective in 1992) banning ocean dumping. But the alternatives are also unsustainable. Landfilling, long the convention in cities far from oceans, pollutes groundwater. Incineration, in addition to pumping toxic chemicals into the air, generates dioxins that can be lethal in only parts per billion.
Both landfilling and incineration were employed for a number of years until environmental objections intensified. To fill the vacuum caused by this opposition, US Environmental Protection Agency (EPA) adopted the idea of disposing of the sludge by spreading it -- as a "fertilizer" -- on agricultural land. Sludge’s four main categories of pollutants -- nutrients, pathogens, toxic organics and heavy metals -- behave differently and cannot be managed by a single kind of treatment. Land application was implemented in Sweden in the early 1980s with disastrous results, which the US EPA seems to be ignoring. Such a practice must lead to accumulation in living tissues of heavy metals and persistent organic chemicals: first, they accumulate in the soil, then in decomposer microbes and soil-conditioning invertebrates. Other life forms are damaged as thousands of non-biocompatible substances move up the food chain. The toxic effect on crops, as well as on the consumers of such crops, is buying risks for the future.
Sludge should either be isolated in secure storage, as nuclear waste is, or it should be processed by means of emerging technologies such as gasification which, through high-heat oxidation, avoids the creation of dioxins in the stack gases and reduces the sludge to a mineral ash. Both these strategies have the advantage of making possible the minimizing of the contact of sludge with life, rather than the maximizing of it as is currently the case with land-application.
Sewer Avoidance
Such a policy has two parts. First, in the thousands of cities, towns, and communities around the world now served by one kind of on-site sanitation system or another (e.g., pit latrines, cesspools, and septic fields), just don't sewer. Instead, use development funds to install on-site remediation technologies, of which there are a number already on the market superior to septic systems in their ability to accomplish pollution prevention or abatement. The advantages of such a program are great:
a) development of communities is not bound to the rigid grid of sewer lines;
b) pollution problems can be dealt with piecemeal -- where they really exist, and where they are worst first;
c) capital as well as maintenance costs are substantially lower for on-site systems than for central sewering and treatment;
d) most importantly, the problem of water pollution becomes solvable instead of merely transferable.
Second, in cities and towns that are already sewered, implement a back-off-the-sewer program. That is, begin the process of intercepting -- and recovering for recycling -- the resources (the constituents of so-called "waste") as close to the source as possible. This does not mean closing existing central treatment facilities now: rather, it means implementing a policy of mandates to fund the use of existing technologies that can accomplish separation, recovery, and recycling at source. The aim is gradually to reduce the range and quantity of random materials entering the sewage stream, in order gradually to decrease the burden on central treatment facilities and, thereby, the volume of sludge produced. This back-off-the-sewers program includes the following:
a) Do not extend sewer lines. Local pollution of groundwater is not, overall, more environmentally destructive than massive relocated pollution caused by central treatment outfalls of partially treated effluent and the dumping, burning, or land application of sewage sludge. Instead, funds now allocated for the extension of sewer lines should be saved for implementation of systematic source reduction, source separation, and resource recovery technologies.
b) Upgrade the level of treatment in those plants where immediate protection of the priority recipient body of water is deemed worth the environmental damage to be incurred by the increased production of toxic sludge.
c) Implement programs of industrial point-source separation, and enforce those that exist. Because adequate data concerning industrial processes are available, it is comparatively easy to apply specific source separation techniques to industrial wastes. It is also relatively easy for regulatory agencies to monitor and control industrial discharges.
d) Beginning at the peripheries of sewered communities whose central treatment facilities are already overloaded, install composting equipment designed to convert to humus -- on-site -- all human excreta. This would intercept most organic and nutrient "waste" materials at their source, thus avoiding the problems characteristic of all efforts to remove them afterwards.
On-site Separation and Resource Recovery Technologies:
Many technologies exist and have been in use long enough to be well understood which represent definite improvements over either septic systems or pit latrines from the point of view of sustainability. The most advanced in this respect is the combination of composting toilet and separated greywater treatment. Besides making sewer- avoidance possible, this approach makes it possible for all the resources involved -- urine, feces, food scraps, washwater, and all the soaps and other "pollutants" in washwater, to remain in the nutrient cycles. The excreta is stabilized before removal from the composting unit and then recycled back, odorless and safe, to agriculture. The washwater is used for irrigation of trees, shrubs, and gardens around the dwelling, in which process it will be cleaned by topsoil and then replenishes ground water. In this nutrient-cycling configuration, today’s damaging path exemplified by sewage creation, central collection and treatment and the resultant production of sludge -- can be avoided altogether.
Such genuinely sustainable technologies should be systematically supported by education programs, as well as by development money for mass installation, both for remediation and for new construction.
Getting the Price of Water Right:
Any steps toward according water its true value will necessarily tend to make the more sustainable technologies more attractive to governments and to industries which now misuse water simply because it is so cheap. The importance of such a policy shift is self-evident.
SUMMARY:
Central sewerage can never be made sustainable. The random mixing of unknown materials is inherently unsustainable. Spending any resources -- money, time, energy, materials -- on the extension of central treatment, either of the sewer lines and hook-ups or higher levels of treatment, is a waste of those resources.
From the point of view of environmental sustainability, any on-site sanitation system is better than central collection and treatment. This is true even of traditional and conventional on-site systems such as pit latrines and septic systems, which can -- and do --pollute. But it is precisely because they are on-site that their remediation and upgrade through replacement with non-polluting, resource- recovery technologies is feasible. And given that such remediation is technically possible to do now without any lowering of the quality of life, there is no legitimate reason why this course should not be systematically pursued. The technologies exist: the political will to make it happen must be mobilized.
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