Land Disposal of Sludge
                                                                                                                  update December 31, 2009

Land disposal of sewage effluents, both liquid and dry, is the goal of EPA based on its interpretation of the CWA Grant
requirements funding the construction of sewage treatment plants in the 70s.
Antibiotic resistant bacteria are concentrated in sewage sludge. The fecal coliform test used to assure the public sludge
is safe inhibits the growth of E. coli and suppresses the growth of other similar gram negative bacteria referred to as
coliforms, while bacteria in the sludge continue to grow at normal rates until desiccation occurs and the bacteria
become dormant -- that is viable but nonculturable. Public  health is not a concern as EPA is aware that bacteria will
survive over 70 weeks on grazing land before going dormant -- and -- revive when food and moisture is available. For
the Part 503 risk assessment, the Office of Water's wastewater division did not consider any of the known carcinogens
in sludge to cause cancer under the exposure pathways examined. Nor did it include any chemical in the risk
assessment. See 1995 Guide to Part 503 risk assessment.

PROCEEDINGS of The Surgeon General’s Conference on Solid Waste Management FOR METROPOLITAN
air dried sludge is used by the National Park Service as fertilizer and soil conditioner in the
numerous parks
in the area."

Proceedings of the Joint Conference on Recycling Municipal Sludges and Effluent On Land

EPA paper from conference --
Lime does not kill salmonella -- it make the bacteria inactive for about 30 days.

Coliform Aerosols Generated from the Surface of Dewatered Sewage Applied to a Forest Clearcut (1978)
Concentrations of airborne coliform bacteria as high as 1.5 x 104 m-3 were observed 8 cm above anaerobically
digested sewage sludge applied to a forest clearcut. Dry conditions and high wind speeds tended to favor aerosol
generation. -- Anaerobically digested, dewatered (20 to 40%
solids) sewage sludge

Coliform bacteria, which are universal indications of fecal pollution, are apparently capable of being aerosolized from
the surface of dewatered sludge applied as a land treatment. It might have been better to use fecal coliforms rather
than total coliforms in this study since the former are better indicators. However, one advantage of using total coliforms
was that aerosolization mechanisms could be better examined because of their longer survival in the sludge. The
highest concentrations generally resulted during warm, dry periods when particles were picked up in the wind. Rain
splash may be another mechanism for aerosolization. It would also appear that the highest numbers are likely to be
generated in the first few months after application, when both total and fecal coliform counts are high. Airborne
coliforms were detected during both the summer and the winter above the sludge and could be detected months
after sludge application.

History of Land Application as a Treatment Alternative

Chicago Metropolitan Sewage District Study concerning bacteria and viruses from sludge on 15,000 acre sludge site.
Study implies waters receiving runoff had less bacteria downstream than upstream

Application to land used for the production of food-chain crops (interim final).
"The annual application of cadmium from solid waste does not exceed 0.5 kilograms per hectare (kg/ha) on land used
for production of tobacco, leafy vegetables or root crops grown for human consumption." For higher levels, "Future
property owners are notified by a stipulation in the land record or property deed which states that the property has
received solid waste at high cadmium application rates and that food-chain crops should not be grown, due to a
possible health hazard." "Solid waste containing concentrations of PCBs equal to or greater than 10 mg/kg (dry weight)
is incorporated into the soil when applied to land used for producing animal feed, including pasture crops for animals
raised for milk."

Acceptable Methods of Sludge Disposal -- [EPA-- Original National Policy Statement]

Health Aspects of Treated Sewage RE-Use  ( WHO # 42)
Sewage irrigation and sludge application should not be undertaken on land employed for growing food crops which will
be eaten raw. An extended period should be allowed after such irrigation has ceased before the land is used again.
Wastewater should not be used to irrigate crops that enter the kitchen in th raw state, unless it is shown to be free from
pathogens, even if the food is to be cooked, because of the risk of cross-contamination. -- the majority of the micro-
organisms are concentrated from wastewater and sludge and remain in the upper portion of the soil. -- if the land is
used to grow food crops the risk of contaminating them is considerable. Larken et al, (2) and other report the survival of
salmonellae and other enteric bacteria in soil and on vegetables for weeks and even months. Mycobacterium bovis
(BCG) has been demonstrated after a month in soil and on lettuce. --  [California reference] There appears to be a
danger of pathogen contamination of vegetables to be eaten raw if wastewater is applied to fields within 2-3 months of
harvesting, thus limiting the usefulness of this form of irrigation for crops such as lettuce and radishes which have short
growing seasons. In sandy soil coliforms may travel more than 800 m (meters); in other cases, a maximum of 450 m has
been reported.

Applicability of the Regulations to Sludge Generated by a POTW [Public Owned Treatment Works]
Q. Is sludge generated by a POTW a hazardous waste?
A. POTW sludge is a solid waste (see Section 261.2(a) and Section 260.10(a)(63). As a solid waste it may be a
hazardous waste.
[EPA has yet to address infectious characteristics of sludge as defined in the RCRA--that sections are still reserved for
some future action]

Enumeration of Potentially Pathogenic Bacteria from Sewage Sludge
[Strange that E. coli, a gram negative bacteria and the fecal coliform is not mentioned]
Conventional methods were successful in enumerating Klebsiella, Staphylococcus, gram-negative enteric bacteria, and
commonly used indicator organisms. Modifications of conventional methods improved the enumeration of Salmonella,
Mycobacterium sp., fluorescent Pseudomonas sp., and Clostridium perfringens.
The best recovery of viable organisms was obtained in samples dispersed by Vortex mixing with glass beads.
The growing practice of disposal to land of these pathogen-containing materials should be coupled with land use
limitations for such sites. Pathogens removed through wastewater treatment should not be reintroduced into a
population via new reservoirs that may be established by irresponsible land management of application
sites. Acreage set aside for food crops that undergo heat processing, for fiber crops, or for forest products can be
utilized reasonably for land disposal. However, other agricultural and recreational lands should not be utilized as
application sites for primary and digested sludge disposal unless the residual has been further
treated by composting, irradiation, or pasteurization.

What We Presently Know About Calf Scours
Infectious diarrhea may be caused by numerous forms of bacteria, but primarily Eschericha coli (colibacillosis),
Salmonella spp. and Clostridium perfringens toxins. Viruses associated with calf scours include rotaviruses,
coronaviruses, BVD, IBR and numerous enteric viruses ..In addition, internal parasites, such as coccidia and some
intestinal worms, have been reported to cause diarrhea in older calves. --
When the advanced state of dehydration and toxicosis is reached, the chances of the calf surviving become greatly

Land Application of Municipal Sewage Sludge For The Production of  Fruits and Vegetables
A Statement of Federal Policy and Guidance
---  Signed by EPA, FDA, USDA
EPA is responsible for maintaining  the integrity  of our environment, FDA is responsibility for maintaining the integrity of
our food products, and USDA is responsible for maintaining the integrity of our agricultural production. All three agree
that heavy metals, toxic organic compounds, and pathogenic microorganisms are a great concern.

EPA, FDA and USDA states that the safety of food grown on sludge is assures as long as the guidance is followed.
There is a caveat, the "government can not offer any indemnity against product recall, seizure, or other enforcement
actions, -- However, the risk of such enforcement actions would be no greater than the risks associated with normal
farming and processing practice." The basic guidance was in the 1979 solid waste regulation Part 257. The policy
"recognizes that pathogen survival is greater in warm, moist environments, than in extremely arid or colder

The Risk to Health of Microbes in Sewage Sludge Applied to Land (1981) ( WHO # 54)
many pathogens appear in raw sludge in numbers greater than the original sewage contribution to the sludge, because
of the concentration effects of sedimentation and absorption.

The [WHO] Working Group considered that sludge and its use on land pose a potential hazard to the health of man and
Both bacterial and viral infections may exist in the carrier state in animals and man without clinical manifestations. The
carrier state in a herd can serve as an effective focus for spreading infection.

Eschericha coli: Certain serotypes are pathogenic to man, animals or both and are particularly virulent in infants.
Problems are caused by plasmid-mediated transfer of drug resistance to other
Enterobacteriaceae, [coliform]
particularly salmonellae, in the gut. As these serotypes re always present in sewage it is possible that sludge may play a
role in their dissemination.

Other Enterobacteriaceae and
Pseudomonas aeruginosa. These organisms are all ubiquitous in the natural
environment and therefore should not be considered in particular.

Quantitative evidence has demonstrated high levels of Salmonellae in sludge and their survival for many weeks in
sludge, on grassland, and in stored grass. The seasonal incidence from 1969 to 1978 of Salmonella isolations from
cattle (26646 sample) has been related to the times of yea at which sludge was applied, and evidence from studies of
carrier rates and serotypes in cattle grazed on sludge-treated pastures has indicated a positive association and a cycle
of infection existing (man-sludge-animals-man). It has not been possible to control this cycle by improvements in meat
inspection at slaughterhouses. Accordingly, the Swiss authorities have decided that sludge must be hygenized before
using on land, The most suitable process is pasteurization prior to anaerobic digestion and in January 1981 there were
three plants in operation.

Sewage Sludge Viral and Pathogenic Agents in Soil-Plant-Animal Systems
Determination was made of the physiologic, pathologic, growth, and reproductive response of cattle, swine and poultry
that were fed sludges, grains, or forages from soil pretreated with urban liquid digested sludges, as well as health
effects in mice receiving liver and kidney tissues from steers and swine exposed to such feeds or contaminants. --
Tissues from animals intended foe human consumption exposed to sarcocyst contaminated sewage sludges may serve
as health hazards for animals and humans. -- Reproductive performance was more suppressed in the second
generation sows than in the first. --Metals were translocated through the cattle and swine tissues with increased levels
of cadmium, nickel, chromium, and lead in liver and tissues of mice. These increase in mice were associated with
decreases in number of mice weaned in the treated versus the control group.

Density Levels of Pathogenic Bacteria in Municipal Wastewater Sludge -- A Literature Review
Mesophilic composting may inactivate bacteria and viruses -- Aspergillus  thrive

Production of Non-Food-Chain Crops with Sewage Sludge
Cotton, sod, and energy biomass trees were determined to have the best potential for cultivation using sewage sludge,
based on the market values and nutrient requirements for each crop and on the hectares presently cultivation for
production of these crops. -- although the total cost for fertilization using commercial fertilizer are less than the cost of
using sewage sludge, the latter would be viewed more favorably if the municipality generating the sludge bore the cost.

Lime Stabilization and Ultimate Disposal of Municipal Wastewater Sludges
Bacterial analysis demonstrated that liming a sludge to pH of 12 is an effective means of inactivating total and fecal
coliform, although organisms can regrow as the pH drops in stockpiled sludge. These surviving bacteria can "regrow" or
can recover from inactivation if sludge pH drops and causes the sludge to become "unstablized". [If] pH drops, bacteria
can regrow in stockpiles. When such piles are broken down, the sludge gives off offensive odors. - operators must
understand that the primary goal of stabilization is not to control odors but to protect public health.

Aerosols Generated by Liquid Sludge Application to Land
The policy of the Environmental Protection Agency is to "press vigorously for public-owned treatment works to utilize
land treatment processes to reclaim and recycle municipal wastewater" -- sludge will be produced at the rate of 4 and
one-half billion dry kilograms annually by the early 1980s. -- The presence of microbiological organisms in sludge, as
well as toxic metals, pesticides and polychlorinated biphenyls (PCBs) suggests that the composition of sludge should be
well known before land application is accomplished. In addition to aerosol generation, there is a potential for harmful
effects through soil and ground water, and there should be some assurance prior to land application that levels of these
contaminates do not exceed tolerable levels.


Health Effects of Land Treatment: Microbiological (1982)
Norman Edward Kowal
EPA quotes from the 1863 work, The Natural Laws of Husbandry,
Even the most ignorant peasant is quite aware that th rain falling upon his dung-heap washes away a great many silver
dollars, and that it would be much more profitable to him to have on his fields what now poisons the air of his house and
streets of the village; but he looks on unconcerned and leaves matters to take their course, because they have always
gone on in the same way.

"In the context of the present-day conventional wastewater treatment we might add "poisons the rivers and streams" as
Surface water pollution from land treatment site runoff is not considered since proper system design should prevent  
direct runoff to surface waters (Sorber and Guter 1975).

Effects on Cattle from Exposure to Sewage Sludge  -- pathogens not considered to infect cattle?
Concentrations of Cu, Pb, and Cd increased in a linear fashion-significant increases in PCBs, DDE, dieldren and
Oxychlordane - Cadmium did not decrease in liver.
Virus in indicator survived 19 weeks, Salmonella survived 70 weeks and Fecal coliform (E. Coli-Klebsiella) 73 weeks.
Sludge desiccation factor in suppressing bacterial growth.

Application of Municipal Sludges on Energy Crops:
A Feasibility Analysis
The term "energy crop refers to any form of biomass (agricultural, woody, or grass crops) grown specifically for its
energy value. The energy may be recovered by direct combustion or through conversion to another form.

A Critical Review of Wastewater Treatment Plant Sludge Disposal by Landfilling
Sludge landfilling (without the addition of municipal refuse) presents many environmental and public health risks and
managerial options. Environmental and public health risks include leachate contamination of water and soil resources,
destruction of native fauna and flora, obnoxious odors, aerosol and dust generation, pathogen transmission, and other
related nuisances.-- The risk of transmitting disease is of major concern for the various sludge disposal practices. The
direct pathways for disease transmission from sludge landfilling landfill operations include aerosols, vector transport,
direct contact, groundwater and surface runoff.

Characterization of Sewage Sludge and Sewage Sludge-Soil Systems
In laboratory incubation experiments, evolution of CO2 from sludge treated soils indicated that elevated levels of trace
metals may temporarily inhibit decomposition, but they do not do so over an extended period. Some temporary  
inhibition of nitrification was observed in sludge-amended soils. -- For oats, metal concentrations  were significantly
greater in the groats than in the hulls. -- Minimal increases in grain metal content were observed when corn was grown
on sludge-amended soils. -- Concentrations of Zn, Cu, Cd, and Ni in wheat and soybean grain were increased by
sludge applications. Bran and meal contained the highest metal concentrations for wheat and soybeans respectively.

Risk of Infectious Disease from Use of Sludge on Land and Methods to Reduce These  Risk
Viruses highly absorbed or contained in solids. Proportion in sludge is high.
Pathogen runoff is a concern as is transmission by crops and livestock .
Infectious dose of many thousands unlikely to be digested to cause disease, however bacteria regrow.
[One organism ingested may triple every hour creating millions/billions within the  one to three days it takes the disease
to show up in the human body]

Development of a Qualitative Pathogen Risk Assessment Methodology for Municipal Sludge Landfilling
[sludge only landfilling -- i.e., surface disposal]
Under proper conditions microbes may actually increase in numbers.

Survival of pathogenic micro-organisms and parasite in excreta, manure and sewage sludge
most pathogenic agents can survive the treatment process" and the sewage treatment process causes some of the
pathogenic disease organisms to be absorbed or enclosed in faecal particles during the treatment process.
"Therefore," according to Strauch, "sewage sludge is rightly described as a
concentration of pathogens." the study  " reported that two groups of researchers had found that pathogenic disease
organisms will be taken up inside the food crops. -- Salmonella has survived in forest stands
between 424 and 820 days --  "In any case, the agricultural utilization of hygienically dubious sewage
sludge poses a risk for the whole national economy"

Preliminary Risk Assessment for Bacteria in Municipal Sewage Sludge Applied to Land
Model does not include regrowth of bacteria in compost or D&M (distribution and marketing) sludge (Class A Biosolids)
Outlines the lack of data needed for future risk assessment.

Preliminary Risk Assessment for Pathogens in Landfilled Municipal Sewage Sludge
[sludge monofill -- i.e. Part 503 surface disposal]
Under default conditions, the risk from both bacterial and viral pathogens exceed the U.S. EPA risk target of not more
that one excess infection in 10,000 people annually (risk of 1 x 10(4) annually or approximately 2x57x10(7) per day).

Part II, 40 CFR 257 et al. Standards for Use and Disposal of Sewage Sludge [Part 503]
Court Ordered Rule based on 1980 National Federal Policy without data to support claims of safety
EPA allows lead to be disposed of on parks, school grounds, home lawns and gardens at a rate of 300 ppm
without restrictions. On agricultural land 300 kilograms per hectare is allowed. Now (2009) EPA wants to ban
lead wheel weights to protect children. EPA also acknowledges a virtual lack of data
[very large file slow to download]

SLUDGE DISPOSAL: Sanitary Landfill - Open Dump - Superfund Site
Presented at New Mexico Conference on the Environment

A Guide to the Biosolids Risk Assessments for the EPA Part 503 Rule
According to EPA,the sludge health risk assessment was only based on looking at 13 organic chemicals which were
either already banned, no longer manufactured or restricted for use. These were dropped from consideration in the rule.
In spite of its own research, EPA said it did not consider any of the cancer causing hazardous heavy metals in sludge to
be cancer causing agents for the risk  assessment. EPA has admitted (1989) that five of the admitted twenty-one
carcinogens in sludge are carcinogenic when inhaled in dust

Use of Reclaimed Water and Sludge in Food Crop Production  (National Academy of Science)
The committee was not constituted to conduct an independent risk assessment of possible health effects, but instead to
review the method and procedures used by EPA in its extensive risk assessment, which was the basis for the Part 503
Sludge Rule. -- It is hoped that this report will be particularly useful to food processors, states, and municipalities in
assessing the use of treated municipal wastewater and sludge in producing crops for human consumption. It highlights
public concerns and regulatory issues likely to be faced, and also identifies some additional areas for research. --  The
recommendations and findings are aimed at authorities at the federal, state, and local levels, public utilities, and the
food processing industry.

Review of National Academy of Science's (NAS) 1996 literary review report by
its National Research Council (NRC) Committee
"Use of Reclaimed Water and Sludge in Food Crop Production"
Based on the report, it is only a matter of time before bacterial food poisoning incidents explode!

"EPA's role in the management of industrial nonhazardous Waste [sludge] is very limited. Under RCRA Subtitle D, EPA
issued minimal criteria prohibiting "open dumps" (40 CFR 257) in 1979. The states, not EPA, are responsible for
implementing the "open dumping criteria," and EPA has no back-up enforcement role." (FR. 62, 19, p. 4284, January
29, 1997)


Strategy for Research on Environmental Risks to Children
Health risks for children are often difficult to recognize and assess because of limited understanding of when and why
children's exposures and responses are different from those of adults.
The objective is to decide how to investigate risks to children. They still don't know.

Office of Inspector General Audit Report, Biosolids Management and Enforcement
EPA officials said investigating health impacts from biosolids is not an EPA responsibility; rather, they believe it is the
responsibility of the National Institute of Occupational Safety and Health, the Centers for Disease Control, and local
health departments. Compliance and Enforce has disinvested from the program.

Abstract at

Office of Inspector General Semiannual Report to Congress
EPA does not plan to complete comprehensive evaluation and monitoring study  to address risk assessments
uncertainties. Also, there are indications more research on pathogens is needed. Of the 12.9 million provided to the
[for PR purposes] , 96 percent ($12.4 million) has been Congressionally mandated.

In 1992-2003 Control of Pathogens and Vector Attractions
EPA said, "If improperly treated sewage sludge was illegally applied to land or placed on a surface
disposal site, humans and animals could be exposed to pathogens directly by coming into contact with the sewage
sludge, or indirectly by consuming drinking water or food contaminated by sewage sludge pathogens. Insects, birds,
rodents, and even farm workers could contribute to these exposure routes by transporting sewage sludge and sewage
sludge pathogens away from the site."

However, there no one to say its illegal since part 503 is self-implementing and the EPA Office of Inspector General
found the EPA office of Enforcement and Compliance Assurance (OECA) provides none  [people], even though it has
program responsibilities. As we explained in our prior report, that office has disinvested from the biosolids program.

Environmental Regulations and Technology, Control of Pathogens and Vector Attraction in Sewage Sludge (PDF) (186
pp, 8.25 MB) (EPA/625/R-92/013) July 2003

Excerpts on exposure from Control of Pathogens and Vector Attractions in Sewage Sludge

Human Health Research Strategy
Identifies  and priorities research need to improve scientific foundation for health risk assessment and research to
enable evaluation of public health outcomes from risk management decisions.

EPA letter to CDC requesting it "review the available information on reported human health effects from the land
application of treated sewage sludge." "Should additional investigative or tracking steps be warranted, we believe the
CDC is uniquely qualified to conduct such efforts."   
[nothing happened]

WEF: Study Finds Fecal Coliforms Appear to Reactivate in Centrifuge Dewatered Solids At  Four of Seven Facilities
Based on the data collected in this study, researchers determined that more coliforms may have actually
been present after anaerobic digestion but were not picked up by the standard culturing method.
Researchers suspect that certain configurations of anaerobic digestion processes lead to conditions which
inhibit the ability of the coliforms to grow and be measured by SCMs. In other words, indicator organisms
may "hibernate" and become "non-culturable." This phenomenon is referred to as "viable but
non-culturable". The issue of viable but non-culturable (VBNC) bacteria was advanced in the 1980s, and
gained significant interest in medicine, the food industry, and many other fields.

EPA letter to the Honorable Joe Simitian, Chair, California Senate Environmental Quality Committee
From: EPA Region 9 trying to get Senate Bill 55 watered down.
The big lie: "A vast amount of effort and scientific research went into developing the hazard profiles, exposure
assessments, and risk assessment in 40 CFR Part 503." See:

2008 --
EPA still claims to have no idea about the danger of pathogens. According to EPA, the assessors do not need to
consider workers because: "These do not include occupational scenarios, which are under the purview of the
Occupational Safety and Health Administration."

Problem Formulation for Human Health Risk Assessments of Pathogens in Land-applied Biosolids In January
2004, the United States Environmental Protection Agency (U.S. EPA) released a final action plan for setting new
priorities for the biosolids program, which included the Agency’s response to the National Research Council (NRC)
report entitled Biosolids Applied to Land: Advancing Standards and Practice (NRC, 2002). This report is an important
step in the Agency’s response because it addresses the development of a problem formulation and analysis plan
relating to uncertainties associated with conducting quantitative microbial risk assessments on land-applied biosolids. --
In addition to providing physical reservoirs of pathogens, biosolids and biosolids-amended soils can serve as sources of
additional pathogens as some of the organisms reproduce (Zaleski et al., 2005a). Evidence about reproduction or lack
of reproduction of particular species is important information for the conceptual models. ---
Four principal biosolids-containing matrices are possible sources of pathogens: liquid biosolids, solid biosolids,
biosolids-amended soil and bioaerosols created from biosolids. Bioaerosols are of particular interest in this problem
formulation. --
One Big Lie. The Part 503 rule defines two categories of biosolids: Class A biosolids, which
have no detectable concentrations of pathogens, and Class B biosolids, which have detectable
concentrations of pathogens (U.S. EPA, 1993).
 Part 503.32 Class A: "Either the density of fecal coliform in the
sewage sludge shall be less than 1000 Most Probable Number per gram of total solids (dry weight basis), or the density
of Salmonella sp. bacteria in the sewage sludge shall be less than three Most Probable Number per four
grams of total solids (dry weight basis) at the time the sewage sludge is used or disposed;" A gram is 1/26th of an

FY2008 Enforcement & Compliance Annual Results
Top Air Enforcement Cases Yield Environmental and Human Health Benefits
Pollutant Reductions
EPA’s 10 largest enforcement actions for stationary source Clean Air Act violations obtained commitments by
companies to reduce their emissions of sulfur oxides (SOx), nitrogen oxides (NOx) and particulate matter (PM).
When all required pollution controls from the 10 enforcement actions are completed, emissions will be reduced by
approximately 1.7 billion pounds per year.

Health Benefits
The annual human health benefits from these reductions in SOx, NOx, and PM are estimated to have a value of $35
billion. These health benefits include:
��approximately 4,000 avoided premature deaths in people with heart or lung disease;
��over 2,000 fewer emergency room visits for such diseases as asthma and respiratory failure;
��about 6,000 fewer cases of chronic bronchitis and acute bronchitis;
�� about 4,000 fewer nonfatal heart attacks;
��over 30,000 fewer cases of upper aggravated asthma;
��over 50,000 fewer cases of upper and lower respiratory symptoms; and
��over 200,000 fewer days when people would miss work or school.


Survey of Wastewater Indicators and Human Pathogen Genomes in Biosolids Produced by Class A and Class B
Stabilization Treatments
Emily Viau and Jordan Peccia* Department of Chemical Engineering, Environmental
Engineering Program, Yale University,   This study also reports the first detection (by culture or PCR) of Staphylococcus
aureus and Clostridium difficile in biosolids. Special attention should be given to the detection of S. aureus genomes
here as a link has been suggested between this organism and infection in residents living near agricultural class B land
application sites (30).
Applied and Environmental Microbiology, January 2009, p. 164-174, Vol. 75, No. 1

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