Sewage sludge

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Desiccation cracks in dried sludge, the hard final remains from a sewage plant Desiccation-cracks hg.jpg
Desiccation cracks in dried sludge, the hard final remains from a sewage plant

Sewage sludge is the residual, semi-solid material that is produced as a by-product during sewage treatment of industrial or municipal wastewater. The term "septage" also refers to sludge from simple wastewater treatment but is connected to simple on-site sanitation systems, such as septic tanks.

Contents

After treatment, and dependent upon the quality of sludge produced (for example with regards to heavy metal content), sewage sludge is most commonly either disposed of in landfills, dumped in the ocean or applied to land for its fertilizing properties, as pioneered by the product Milorganite.[ citation needed ]

The term "Biosolids" is often used as an alternative to the term sewage sludge in the United States, particularly in conjunction with reuse of sewage sludge as fertilizer after sewage sludge treatment. Biosolids can be defined as organic wastewater solids that can be reused after stabilization processes such as anaerobic digestion and composting. [1] Opponents of sewage sludge reuse reject this term as a public relations term. [2] [3]

Treatment process

Sewage sludge treatment is the process of removing contaminants from wastewater. Sewage sludge is produced from the treatment of wastewater in sewage treatment plants and consists of two basic forms — raw primary sludge and secondary sludge, also known as activated sludge in the case of the activated sludge process.

Sewage sludge is usually treated by one or several of the following treatment steps: lime stabilization, thickening, dewatering, drying, anaerobic digestion or composting. Some treatment processes, such as composting and alkaline stabilization, that involve significant amendments may affect contaminant strength and concentration: depending on the process and the contaminant in question, treatment may decrease or in some cases increase the bioavailability and/or solubility of contaminants. [4] Regarding sludge stabilization processes, anaerobic and aerobic digestion seem to be the most common used methods in EU-27. [5]

When fresh sewage or wastewater enters a primary settling tank, approximately 50% of the suspended solid matter will settle out in an hour and a half. This collection of solids is known as raw sludge or primary solids and is said to be "fresh" before anaerobic processes become active. The sludge will become putrescent in a short time once anaerobic bacteria take over, and must be removed from the sedimentation tank before this happens.

This is accomplished in one of two ways. Most commonly, the fresh sludge is continuously extracted from the bottom of a hopper-shaped tank by mechanical scrapers and passed to separate sludge-digestion tanks. In some treatment plants an Imhoff tank is used: sludge settles through a slot into the lower story or digestion chamber, where it is decomposed by anaerobic bacteria, resulting in liquefaction and reduced volume of the sludge.

Sewage sludge in a beaker from a treatment plant SEWAGE SLUDGE SETTLES TO BOTTOM OF BEAKER. SEWAGE TREATMENT PLANT - NARA - 543807.jpg
Sewage sludge in a beaker from a treatment plant

The secondary treatment process also generates a sludge largely composed of bacteria and protozoa with entrained fine solids, and this is removed by settlement in secondary settlement tanks. Both sludge streams are typically combined and are processed by anaerobic or aerobic treatment process at either elevated or ambient temperatures. After digesting for an extended period, the result is called "digested" sludge and may be disposed of by drying and then landfilling.

Following treatment, sewage sludge is either landfilled, dumped in the ocean, incinerated, applied on agricultural land or, in some cases, retailed or given away for free to the general public. [6] [7] According to a review article published in 2012, sludge reuse (including direct agricultural application and composting) was the predominant choice for sludge management in EU-15 (53% of produced sludge), following by incineration (21% of produced sludge). On the other hand, the most common disposal method in EU-12 countries was landfilling. [5]

Quantities produced

The amount of sewage sludge produced is proportional to the amount and concentration of wastewater treated, and it also depends on the type of wastewater treatment process used. It can be expressed as kg dry solids per cubic metre of wastewater treated. The total sludge production from a wastewater treatment process is the sum of sludge from primary settling tanks (if they are part of the process configuration) plus excess sludge from the biological treatment step. For example, primary sedimentation produces about 110–170 kg/ML of so-called primary sludge, with a value of 150 kg/ML regarded as being typical for municipal wastewater in the U.S. or Europe. [1] The sludge production is expressed as kg of dry solids produced per ML of wastewater treated; one mega litre (ML) is 103 m3. Of the biological treatment processes, the activated sludge process produces about 70–100 kg/ML of waste activated sludge, and a trickling filter process produces slightly less sludge from the biological part of the process: 60–100 kg/ML. [1] This means that the total sludge production of an activated sludge process that uses primary sedimentation tanks is in the range of 180–270 kg/ML, being the sum of primary sludge and waste activated sludge.

United States municipal wastewater treatment plants in 1997 produced about 7.7 million dry tons of sewage sludge, and about 6.8 million dry tons in 1998 according to EPA estimates. [8] As of 2004, about 60% of all sewage sludge was applied to land as a soil amendment and fertilizer for growing crops. [9] In a review article published in 2012, it was reported that a total amount of 10.1 million tn DS/year were produced in EU-27 countries. [10] As of 2023, the EU produced 2 to 3 million tons of sludge each year. [11] Worldwide it is estimated that as much as 75 Million Mg of dry sewage sludge per year. [12]

Production of sewage sludge can be reduced by conversion from flush toilets to dry toilets such as urine-diverting dry toilets and composting toilets. [13]

Disposal

Landfill

Sewage sludge deposition in landfills can circulate human-virulent species of Cryptosporidium and Giardia pathogens. Sonication and quicklime stabilization are most effective in inactivation of these pathogens; microwave energy disintegration and top-soil stabilization were less effective. [14] A Texas county has launched a first-of-its-kind criminal investigation into waste management giant Synagro over PFAS-contaminated sewage sludge it is selling to Texas farmers as a cheap alternative to fertilizer. [15]

As of 2023, 11% of sludge produced in the EU was disposed of in landfills. [16] The EU is attempting to phase out the disposal of sludge in landfills. [17]

Ocean dumping

It used to be common practice to dump sewage sludge into the ocean, however, this practice has stopped in many nations due to environmental concerns as well to domestic and international laws and treaties. [18] Ronald Reagan signed the law that prohibited ocean dumping as a means of disposal of sewage sludge in the US in 1988. [19]

Incineration

Sludge can also be incinerated in sludge incineration plants which comes with its own set of environmental concerns (air pollution, disposal of the ash). Pyrolysis of the sludge to create syngas and potentially biochar is possible, as is combustion of biofuel produced from drying sewage sludge or incineration in a waste-to-energy facility for direct production of electricity and steam for district heating or industrial uses.

Thermal processes can greatly reduce the volume of the sludge, as well as achieve remediation of all or some of the biological concerns. Direct waste-to-energy incineration and complete combustion systems (such as the Gate 5 Energy System) will require multi-step cleaning of the exhaust gas, to ensure no hazardous substances are released. In addition, the ash produced by incineration or incomplete combustion processes (such as fluidized-bed dryers) may be difficult to use without subsequent treatment due to high heavy metal content; solutions to this include leaching of the ashes to remove heavy metals or in the case of ash produced in a complete-combustion process, or with biochar produced from a pyrolytic process, the heavy metals may be fixed in place and the ash material readily usable as a LEEDs preferred additive to concrete or asphalt. [20] Examples of other ways to use dried sewage sludge as an energy resource include the Gate 5 Energy System, an innovative process to power a steam turbine using heat from burning milled and dried sewage sludge, or combining dried sewage sludge with coal in coal-fired power stations. In both cases this allows for production of electricity with less carbon-dioxide emissions than conventional coal-fired power stations. [21]

As of 2023, 27% of sludge produced in the EU was incinerated. [22]

Use

Land application

Biosolids is a term widely used to denote the byproduct of domestic and commercial sewage and wastewater treatment that is to be used in agriculture. National regulations that dictate the practice of land application of treated sewage sludge differ widely and e.g. in the US there are widespread disputes about this practice.

A shovel excavator loading solid sewage sludge for land application. Shovel excavator loading the sewage sludge (6305610332).jpg
A shovel excavator loading solid sewage sludge for land application.

Depending on their level of treatment and resultant pollutant content, biosolids can be used in regulated applications for non-food agriculture, food agriculture, [23] or distribution for unlimited use. Treated biosolids can be produced in cake, granular, pellet, or liquid form and are spread over land before being incorporated into the soil or injected directly into the soil by specialist contractors. Such use was pioneered by the production of Milorganite in 1926.[ citation needed ]

Use of sewage sludge has shown an increase in level of soil available phosphorus and soil salinity. [24]

The findings of a 20-year field study of air, land, and water in Arizona, concluded that use of biosolids is sustainable and improves the soil and crops. [25] Other studies report that plants uptake large quantities of heavy metals and toxic pollutants that are retained by produce, which is then consumed by humans. [26] [27] [28]

A PhD thesis studying the addition of sludge to neutralize soil acidity concluded that the practice was not recommended if large amounts are used because the sludge produces acids when it oxidizes. [29]

Studies have indicated that pharmaceuticals and personal care products, which often adsorb to sludge during wastewater treatment, can persist in agricultural soils following biosolid application. [30] Some of these chemicals, including potential endocrine disruptor triclosan, can also travel through the soil column and leach into agricultural tile drainage at detectable levels. [30] [31] Other studies, however, have shown that these chemicals remain adsorbed to surface soil particles, making them more susceptible to surface erosion than infiltration. [32] [33] These studies are also mixed in their findings regarding the persistence of chemicals such as triclosan, triclocarban, and other pharmaceuticals. The impact of this persistence in soils is unknown, but the link to human and land animal health is likely tied to the capacity for plants to absorb and accumulate these chemicals in their consumed tissues. Studies of this kind are in early stages, but evidence of root uptake and translocation to leaves did occur for both triclosan and triclocarban in soybeans. [34] This effect was not present in corn when tested in a different study. [31]

A cautionary approach to land application of biosolids has been advocated by some for regions where soils have lower capacities for toxics absorption or due to the presence of unknowns in sewage biosolids. [35] [36] In 2007 the Northeast Regional Multi-State Research Committee (NEC 1001) issued conservative guidelines tailored to the soils and conditions typical of the northeastern US. [37]

Use of sewage sludge is prohibited for produce to be labeled USDA-certified organic. [38] In 2014 the United States grocery chain Whole Foods banned produce grown in sewage sludge. [39] [40]

Treated sewage sludge has been used in the UK, Europe and China agriculturally for more than 80 years, though there is increasing pressure in some countries to stop the practice of land application due to farm land contamination [41] and negative public opinion. [42] [43] [44] In the 1990s, there was pressure in some European countries to ban the use of sewage sludge as a fertilizer. Switzerland, Sweden, Austria, and others introduced a ban. Still, the dominant method for disposal of sewage sludge in the EU is via application to agricultural lands. [45] As of 2023, 40% of sludge produced in the EU was used on agricultural land. [46] Since the 1960s there has been cooperative activity with industry to reduce the inputs of persistent substances from factories. This has been very successful and, for example, the content of cadmium in sewage sludge in major European cities is now only 1% of what it was in 1970. [47]

Transformation into Products

Sewage sludge is an agglomeration of concentrated wastes, and therefore it contains many potentially extractable and useable components. [48] These can include using sludge to produce energy, create carbon-based components, extract phosphorus and nitrogen, or make bricks or other construction materials. [48]

Recycling of phosphate is regarded as especially important because the phosphate industry predicts that at the current rate of extraction the economic reserves will be exhausted in 100 or at most 250 years. [49] Phosphate can be recovered with minimal capital expenditure as technology currently exists, but municipalities have little political will to attempt nutrient extraction, instead opting for a "take all the other stuff" mentality. [50] [ unreliable source? ]

One potential drawback of extracting products from sludge — as opposed to land application — is that only some of the sludge is used and the rest still needs disposal. [48] It can also be very expensive to develop and use appropriate technologies for extracting resources. [48]

Contaminants

The specific content of sewage sludge is affected by what enters the sewage stream, and how the sewage is treated and processed. As wastewater treatment policies are passed or amended to allow or regulate potential contaminants into the sewage stream, the content of the sewage sludge reflects those changes. For example, the EU's Urban Waste Water Treatment Directive shapes the types of contaminants that enter the EU's sewage treatment stream. [51]

Pathogens

Bacteria in treated sludge products can actually regrow under certain environmental conditions. [52] Pathogens could easily remain undetected in untreated sewage sludge. [53] Pathogens are not a significant health issue if sewage sludge is properly treated and site-specific management practices are followed. [54]

Heavy metals

One of the main concerns in the treated sludge is the concentrated metals content (lead, arsenic, cadmium, thallium, etc.); certain metals are regulated while others are not. [55] Leaching methods can be used to reduce the metal content and meet the regulatory limit. [56]

In 2009, the EPA released the Targeted National Sewage Sludge Study, which reports on the level of metals, chemicals, hormones, and other materials present in a statistical sample of sewage sludges. [57] Some highlights include:

Microplastic contamination from use of sewage sludge on agricultural land in Europe, 2016. Plastic Atlas-SPREADING AROUND Microplastic sewage sludge spread fields per year tonnes Sweden Finland United Kingdom Estonia Germany Po.png
Microplastic contamination from use of sewage sludge on agricultural land in Europe, 2016.

Micro-pollutants

Micro-pollutants are compounds which are normally found at concentrations up to microgram per liter and milligram per kilogram in the aquatic and terrestrial environment, respectively, and they are considered to be potential threats to environmental ecosystems. They can become concentrated in sewage sludge. [58] Each of these disposal options comes with myriad potential—and in some cases proven—human health and environment impacts. [36] Several organic micro-pollutants such as endocrine disrupting compounds, pharmaceuticals and per-fluorinated compounds have been detected in sewage sludge samples around the world at concentrations ranging up to some hundreds mg/kg of dried sludge. [59] [60] Sterols and other hormones have also been detected. [57]

Other hazardous substances

Sewage treatment plants receive various forms of hazardous waste from hospitals, nursing homes, industry and households. Low levels of constituents such as PCBs, dioxin, and brominated flame retardants, may remain in treated sludge. [61] [62] There are potentially thousands of other components of sludge that remain untested/undetected disposed of from modern society that also end up in sludge (pharmaceuticals, nano particles, etc.) which have been proven to be hazardous to both human and ecological health. [58]

In 2013, in South Carolina PCBs were discovered in very high levels in wastewater sludge. The problem was not discovered until thousands of acres of farm land in South Carolina were discovered to be contaminated by this hazardous material. SCDHEC issued emergency regulatory order banning all PCB laden sewage sludge from being land applied on farm fields or deposited into landfills in South Carolina. [63] [64]

Also in 2013, after DHEC request, the city of Charlotte decided to stop land applying sewage sludge in South Carolina while authorities investigated the source of PCB contamination. [65] In February 2014, the city of Charlotte admitted PCBs have entered their sewage treatment centers as well. [66]

Contaminants of concern in sewage sludge are plasticizers, PDBEs, PFASs ("forever chemicals"), [67] and others generated by human activities, including personal care products and medicines. Synthetic fibers from fabrics persist in treated sewage sludge as well as in biosolids-treated soils and may thus serve as an indicator of past biosolids application. [68]

Pollutant ceiling concentration

The term "pollutant" is defined as part of the EPA 503 rule. The components of sludge have pollutant limits defined by the EPA. "A Pollutant is an organic substance, an inorganic substance, a combination of organic and inorganic substances, or a pathogenic organism that, after discharge and upon exposure, ingestion, inhalation, or assimilation into an organism 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." [69] The maximum component pollutant limits by the US EPA are:

PollutantCeiling concentration (mg per kg)
Cadmium 85
Copper 4300
Lead 840
Mercury 57
Molybdenum 75
Nickel 420
Selenium 100
Zinc 7500

Health risks

In 2011, the EPA commissioned a study at the United States National Research Council (NRC) to determine the health risks of sludge. [70] In this document the NRC pointed out that many of the dangers of sludge are unknown and unassessed.

The NRC published "Biosolids Applied to Land: Advancing Standards and Practices" in July 2002. The NRC concluded that while there is no documented scientific evidence that sewage sludge regulations have failed to protect public health, there is persistent uncertainty on possible adverse health effects. [71] The NRC noted that further research is needed and made about 60 recommendations for addressing public health concerns, scientific uncertainties, and data gaps in the science underlying the sewage sludge standards. The EPA responded with a commitment to conduct research addressing the NRC recommendations. [72]

Residents living near Class B sludge processing sites may experience asthma or pulmonary distress due to bioaerosols released from sludge fields. [73]

A 2004 survey of 48 individuals near affected sites found that most reported irritation symptoms, about half reported an infection within a month of the application, and about a fourth were affected by Staphylococcus aureus , including two deaths. The number of reported S. aureus infections was 25 times as high as in hospitalized patients, a high-risk group. The authors point out that regulations call for protective gear when handling Class B biosolids and that similar protections could be considered for residents in nearby areas given the wind conditions. [74]

In 2007, a health survey of persons living in close proximity to Class B sludged land was conducted. [75] A sample of 437 people exposed to Class B sludge (living within 1-mile (1.6 km) of sludged land) - and using a control group of 176 people not exposed to sludge (not living within 1-mile (1.6 km) of sludged land) reported the following:

"Results revealed that some reported health-related symptoms were statistically significantly elevated among the exposed residents, including excessive secretion of tears, abdominal bloating, jaundice, skin ulcer, dehydration, weight loss, and general weakness. The frequency of reported occurrence of bronchitis, upper respiratory infection, and giardiasis were also statistically significantly elevated. The findings suggest an increased risk for certain respiratory, gastrointestinal, and other diseases among residents living near farm fields on which the use of biosolids was permitted."

— Khuder, et al., Health Survey of Residents Living near Farm Fields Permitted to Receive Biosolids [75]

Although correlation does not imply causation, such extensive correlations may lead reasonable people to conclude that precaution is necessary in dealing with sludge and sludged farmlands.

Harrison and Oakes suggest that, in particular, "until investigations are carried out that answer these questions (...about the safety of Class B sludge...), land application of Class B sludges should be viewed as a practice that subjects neighbors and workers to substantial risk of disease." [23] They further suggest that even Class A treated sludge may have chemical contaminants (including heavy metals, such as lead) or endotoxins present, and a precautionary approach may be justified on this basis, though the vast majority of incidents reported by Lewis, et al. have been correlated with exposure to Class B untreated sludge and not Class A treated sludge.

A 2005 report by the state of North Carolina concluded that "a surveillance program of humans living near application sites should be developed to determine if there are adverse health effects in humans and animals as a result of biosolids application." [76]

Studies of the potential uses of sewage sludge around homes, such as covering lead-contaminated soil in Baltimore, have created debates over whether participants should have been informed about potential risks, when there remains uncertainty about those risks. [77]

The chain of sewage sledge to biosolids to fertilizers has resulted in PFASs ("forever chemicals") contamination of farm produce in Maine in 2021 [78] and beef raised in Michigan in 2022. [79] The EPA PFAS Strategic Roadmap initiative, running from 2021 to 2024, will consider the full lifecycle of PFAS including health risks of PFAS in wastewater sludge. [80]

Regulation and guidelines

European Union

EU heavy metal limits.png

The EC encourages the use of sewage sludge in agriculture because it conserves organic matter and completes nutrient cycles.

European countries that joined the EU after 2004 favor landfills as a means of disposal for sewage sludge. [81] In 2006, the predicted sewage sludge growth rate was 10 million tons of sewage sludge per year. [82] This increase in the amount of sewage sludge accumulation in the EU can be due to the increase in the number of households that are connected to the sewage system. [83] The EU has directives in place to encourage the use of sewage sludge in agriculture, in a way that the soil, humans, and the environment are not harmed. [84] A guideline the EU has put into place it that sewage sludge should not be added to fruit and vegetable crops that are in season. [84] In Austria, in order to dispose of the sewage sludge in a landfill, it must first be treated in a way that reduces its biological reactivity. [85] Sweden no longer allows sewage sludge to be disposed in the land fills. [85] In the EU, regulations regarding sewage sludge disposal differ because legislation regarding landfill disposal in not in the national regulations for the EU. [85]

Sewage Sludge Directive

The EU's Sewage Sludge Directive (86/278/EEC) sets out regulations to pursue the dual purpose of promoting the use of sewage sludge as an agricultural fertilizer, while ensuring environmental protections and human health. [86] [87] These rules include sludge treatment requirements, as well as limits on the time and place of sewage sludge applications, depending on the type of food crop. [87] [88] This is intended to protect human health while maintaining the ecological health of the soil and water. [89] The directive explicitly regulates the allowable levels of seven heavy metals (cadmium, copper, nickel, lead, zinc, mercury, and chromium) in soil and sludge, and regulates any application of sewage sludge that would cause levels of these heavy metals in soil to exceed those limits. [87] [89]

EU member states are tasked with implementing and enforcing the Directive within their borders, as well as monitoring and reporting on sludge production, treatment, characteristics, and use. [90] [91] Member states are allowed to set more stringent limits for heavy metals than set out in the Sewage Sludge Directive, and can set limits for other pollutants. [92] [93] [91] As of 2021, more than half of the EU member states had stricter limits for mercury and cadmium than required under the Directive. [93]

Member states are also allowed to limit or promote the use of sewage sludge for agriculture as they choose, meaning that some countries prohibit the use of sludge in agriculture, while some use up to 50% of the sludge they generate in agriculture. [94] Spain, France, Italy, and the United Kingdom (while it was still part of the EU) have particularly promoted the use of sludge in agriculture. [93] Each of Austria's federal states has its own regulations for the use of sewage sludge in agriculture, including different limits for heavy metals. [95] For example, Tyrol has banned the use of sludge on agricultural lands, while in Salzburg it is only allowed under certain conditions. [95]

Since the Directive's passage, there has been the substantial decrease in heavy metal residues in agricultural soils over time (well below the limits set), though it is not possible to determine what proportion of the decrease is due to the Directive itself, as opposed to other national and EU legislation. [96] [97]

The Sewage Sludge Directive has been evaluated several times under EU proposals to build a circular economy through the reduction and reuse of wastes. [98] [99] In 2014, a European Commission evaluation of the Sewage Sludge Directive suggested it was appropriate for its goals, and did not need revision. [100] [98] In 2023, as part of the European Green Deal and Circular Economy Action Plan, the EU re-evaluated the Sewage Sludge Directive, and found that it should be maintained – as the use of sewage sludge as fertilizer aligns with circular economy goals and potentially reduces the EU carbon emissions – but that the potential pollutants and contaminants regulated under the Directive should be reviewed and potentially revised. [101] [99] [102] This evaluation noted that, as of 2023, the original Directive had not been seriously updated since its original passage in 1986, even though in the intervening decades there had been many developments in both environmental policy, expectations, and research, as well as member states' national policies around sewage sludge. [101] The evaluation particularly emphasized concerns about methane emissions, microplastic contamination, and antibiotic resistances. [101]

The Sewage Sludge Directive has not yet set limits for other contaminants, such as organic pollutants, pathogens, microplastics, pharmaceutical residues, and personal care product residues. [103] [104] With the identification of these new contaminants in sludge since the Sewage Sludge Directive originally passed, several researchers have suggested that the EU should consider revising the Directive to address their potential risks to health and environment. [104] [105]

United States

After the 1991 Congressional ban on ocean dumping, the U.S. Environmental Protection Agency (EPA) instituted a policy of digested sludge reuse on agricultural land. The US EPA promulgated regulations – 40 CFR Part 503 – that continued to allow the use of biosolids on land as fertilizers and soil amendments which had been previously allowed under Part 257. The EPA promoted biosolids recycling throughout the 1990s. The EPA's Part 503 regulations were developed with input from university, EPA, and USDA researchers from around the country and involved an extensive review of the scientific literature and the largest risk assessment the agency had conducted to that time. The Part 503 regulations became effective in 1993. [106]

According to the EPA, biosolids that meet treatment and pollutant content criteria of Part 503.13 "can be safely recycled and applied as fertilizer to sustainably improve and maintain productive soils and stimulate plant growth." However, they can not be disposed of in a sludge only landfill under Part 503.23 because of high chromium levels and boundary restrictions.

Under the Obama Administration, the Biosolids Center of Excellence (headquartered in EPA Region 7) was created to monitor and enforce compliance with biosolids regulation. [107] The Center receives and reviews annual reports from the major producers of biosolids. [107]

Eight US states oversee their own biosolids programs: Arizona, Michigan, Ohio, Oklahoma, South Dakota, Texas, Utah, and Wisconsin; other states' programs are overseen by the EPA. [107]

Classes of sewage sludge in the United States

In the United States, two classes of sewage sludge are defined by the amount of pathogens (i.e. bacteria, viruses) remaining in the sludge, and therefore the types of uses allowed by law. [108] [109] Both classes of sludge may still contain radioactive or pharmaceutical wastes. [110] [111]

Class A sludge must be treated so that specific pathogens (like Salmonella) are no longer detected. This class of sludge can be used for all land applications, including where the public may come into contact with it (i.e. agricultural land, home use, for public sale). [108] [109] Biosolids that meet Class A pathogen reduction requirements or equivalent treatment by a "Process to Further Reduce Pathogens" (PFRP) have the least restrictions on use. PFRPs include pasteurization, heat drying, thermophilic composting (aerobic digestion, most common method), and beta or gamma ray irradiation. [112]

Class B sludge also requires treatment to reduce pathogens, but pathogens are still detectable in the sludge (such as some parasitic worm eggs). [109] This class of sludge has much stricter restrictions on its use. [108] [109] Biosolids that meet the Class B pathogen treatment and pollutant criteria, in accordance with the EPA "Standards for the use or disposal of sewage sludge" (40 CFR Part 503), can be land applied with formal site restrictions and strict record keeping. [113]

Evaluation of the US Sewage Sludge Program

The EPA Office of the Inspector General (OIG) completed two assessments in 2000 and 2002 of the EPA sewage sludge program. The follow-up report in 2002 documented that "the EPA cannot assure the public that current land application practices are protective of human health and the environment." The report also documented that there had been an almost 100% reduction in EPA enforcement resources since the earlier assessment. This is probably the greatest issue with the practice: under both the federal program operated by the EPA and those of the several states, there is limited inspection and oversight by agencies charged with regulating these practices. To some degree, this lack of oversight is a function of the perceived (by the regulatory agencies) benign nature of the practice. However, a greater underlying issue is funding. Few states and the US EPA have the discretionary funds necessary to establish and implement a full enforcement program for biosolids. [114]

As detailed in the 1995 Plain English Guide to the Part 503 Risk Assessment, the EPA's most comprehensive risk assessment was completed for biosolids. [115]

Court cases in the United States

  • In 2009, James Rosendall of Grand Rapids, MI was sentenced by United States District Judge Avern Cohn to 11 months in prison followed by three years of supervised release for conspiring to commit bribery. Rosendall was the former president of Synagro of Michigan, a subsidiary of Synagro Technologies. His duties included obtaining the approval of the City of Detroit to process and dispose of the city's wastewater. [116] [117]
  • In 2011, Travis County Commissioners declared that Synagro's solid waste disposal activities would be inappropriate and prohibited land use according to the towns already established ordinances. [118]
  • A battle between the home rule of local government and states rights/commerce rights has been waged between the small town of Kern County, California, and Los Angeles, California. Kern county passed an ordinance "Keep Kern Clean" ballot initiative which banned sludge from being applied in Kern County. Los Angeles sued and after a protracted verdict, won the case in 2016. [119] [120] [121]
  • In 2012, two families won a $225,000 tort lawsuit against a sludge company that contaminated their properties. [122]
  • In 2013 in Pennsylvania, the case Gilbert vs. Synagro, a judge barred a nuisance, negligence and trespass lawsuit under Pennsylvania's Right to Farm Act. [123]

History of sewage sludge disposal in New York City

Since 1884 when sewage was first treated the amount of sludge has increased along with population and more advanced treatment technology (secondary treatment in addition to primary treatment). In the case of New York City, at first the sludge was discharged directly along the banks of rivers surrounding the city, then later piped further into the rivers, and then further still out into the harbor. [124] In 1924, to relieve a dismal condition in New York Harbor, New York City began dumping sludge at sea at a location in the New York Bight called the 12-Mile Site. This was deemed a successful public health measure and not until the late 1960s was there any examination of its consequences to marine life or to humans. There was accumulation of sludge particles on the seafloor and consequent changes in the numbers and types of benthic organisms. In 1970 a large area around the site was closed to shellfishing. From then until 1986, the practice of dumping at the 12-Mile Site came under increasing pressure stemming from a series of untoward environmental crises in the New York Bight that were attributed partly to sludge dumping. In 1986, sludge dumping was moved still further seaward to a site over the deep ocean called the 106-Mile Site. Then, again in response to political pressure arising from events unrelated to ocean dumping, the practice ended entirely in 1992. Since 1992, New York City sludge has been applied to land (outside of New York state). The wider question is whether or not changes on the sea floor caused by the portion of sludge that settles are severe enough to justify the added operational cost and human health concerns of applying sludge to land.

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Industrial waste is the waste produced by industrial activity which includes any material that is rendered useless during a manufacturing process such as that of factories, mills, and mining operations. Types of industrial waste include dirt and gravel, masonry and concrete, scrap metal, oil, solvents, chemicals, scrap lumber, even vegetable matter from restaurants. Industrial waste may be solid, semi-solid or liquid in form. It may be hazardous waste or non-hazardous waste. Industrial waste may pollute the nearby soil or adjacent water bodies, and can contaminate groundwater, lakes, streams, rivers or coastal waters. Industrial waste is often mixed into municipal waste, making accurate assessments difficult. An estimate for the US goes as high as 7.6 billion tons of industrial waste produced annually, as of 2017. Most countries have enacted legislation to deal with the problem of industrial waste, but strictness and compliance regimes vary. Enforcement is always an issue.

<span class="mw-page-title-main">Septic tank</span> Method for basic wastewater treatment (on-site)

A septic tank is an underground chamber made of concrete, fiberglass, or plastic through which domestic wastewater (sewage) flows for basic sewage treatment. Settling and anaerobic digestion processes reduce solids and organics, but the treatment efficiency is only moderate. Septic tank systems are a type of simple onsite sewage facility. They can be used in areas that are not connected to a sewerage system, such as rural areas. The treated liquid effluent is commonly disposed in a septic drain field, which provides further treatment. Nonetheless, groundwater pollution may occur and is a problem.

<span class="mw-page-title-main">Water pollution</span> Contamination of water bodies

Water pollution is the contamination of water bodies, with a negative impact on their uses. It is usually a result of human activities. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and groundwater. Water pollution results when contaminants mix with these water bodies. Contaminants can come from one of four main sources. These are sewage discharges, industrial activities, agricultural activities, and urban runoff including stormwater. Water pollution may affect either surface water or groundwater. This form of pollution can lead to many problems. One is the degradation of aquatic ecosystems. Another is spreading water-borne diseases when people use polluted water for drinking or irrigation. Water pollution also reduces the ecosystem services such as drinking water provided by the water resource.

<span class="mw-page-title-main">Wastewater treatment</span> Converting wastewater into an effluent for return to the water cycle

Wastewater treatment is a process which removes and eliminates contaminants from wastewater. It thus converts it into an effluent that can be returned to the water cycle. Once back in the water cycle, the effluent creates an acceptable impact on the environment. It is also possible to reuse it. This process is called water reclamation. The treatment process takes place in a wastewater treatment plant. There are several kinds of wastewater which are treated at the appropriate type of wastewater treatment plant. For domestic wastewater the treatment plant is called a Sewage Treatment. Municipal wastewater or sewage are other names for domestic wastewater. For industrial wastewater, treatment takes place in a separate Industrial wastewater treatment, or in a sewage treatment plant. In the latter case it usually follows pre-treatment. Further types of wastewater treatment plants include Agricultural wastewater treatment and leachate treatment plants.

<span class="mw-page-title-main">Clean Water Act</span> 1972 U.S. federal law regulating water pollution

The Clean Water Act (CWA) is the primary federal law in the United States governing water pollution. Its objective is to restore and maintain the chemical, physical, and biological integrity of the nation's waters; recognizing the responsibilities of the states in addressing pollution and providing assistance to states to do so, including funding for publicly owned treatment works for the improvement of wastewater treatment; and maintaining the integrity of wetlands.

<span class="mw-page-title-main">Reclaimed water</span> Converting wastewater into water that can be reused for other purposes

Water reclamation is the process of converting municipal wastewater or sewage and industrial wastewater into water that can be reused for a variety of purposes. It is also called wastewater reuse, water reuse or water recycling. There are many types of reuse. It is possible to reuse water in this way in cities or for irrigation in agriculture. Other types of reuse are environmental reuse, industrial reuse, and reuse for drinking water, whether planned or not. Reuse may include irrigation of gardens and agricultural fields or replenishing surface water and groundwater. This latter is also known as groundwater recharge. Reused water also serve various needs in residences such as toilet flushing, businesses, and industry. It is possible to treat wastewater to reach drinking water standards. Injecting reclaimed water into the water supply distribution system is known as direct potable reuse. Drinking reclaimed water is not typical. Reusing treated municipal wastewater for irrigation is a long-established practice. This is especially so in arid countries. Reusing wastewater as part of sustainable water management allows water to remain an alternative water source for human activities. This can reduce scarcity. It also eases pressures on groundwater and other natural water bodies.

<span class="mw-page-title-main">Biosolids</span> Decontaminated sewage sludge

Biosolids are solid organic matter recovered from a sewage treatment process and used as fertilizer. In the past, it was common for farmers to use animal manure to improve their soil fertility. In the 1920s, the farming community began also to use sewage sludge from local wastewater treatment plants. Scientific research over many years has confirmed that these biosolids contain similar nutrients to those in animal manures. Biosolids that are used as fertilizer in farming are usually treated to help to prevent disease-causing pathogens from spreading to the public. Some sewage sludge can not qualify as biosolids due to persistent, bioaccumulative and toxic chemicals, radionuclides, and heavy metals at levels sufficient to contaminate soil and water when applied to land.

<span class="mw-page-title-main">Agricultural wastewater treatment</span> Farm management for controlling pollution from confined animal operations and surface runoff

Agricultural wastewater treatment is a farm management agenda for controlling pollution from confined animal operations and from surface runoff that may be contaminated by chemicals in fertilizer, pesticides, animal slurry, crop residues or irrigation water. Agricultural wastewater treatment is required for continuous confined animal operations like milk and egg production. It may be performed in plants using mechanized treatment units similar to those used for industrial wastewater. Where land is available for ponds, settling basins and facultative lagoons may have lower operational costs for seasonal use conditions from breeding or harvest cycles. Animal slurries are usually treated by containment in anaerobic lagoons before disposal by spray or trickle application to grassland. Constructed wetlands are sometimes used to facilitate treatment of animal wastes.

<span class="mw-page-title-main">Industrial wastewater treatment</span> Processes used for treating wastewater that is produced by industries as an undesirable by-product

Industrial wastewater treatment describes the processes used for treating wastewater that is produced by industries as an undesirable by-product. After treatment, the treated industrial wastewater may be reused or released to a sanitary sewer or to a surface water in the environment. Some industrial facilities generate wastewater that can be treated in sewage treatment plants. Most industrial processes, such as petroleum refineries, chemical and petrochemical plants have their own specialized facilities to treat their wastewaters so that the pollutant concentrations in the treated wastewater comply with the regulations regarding disposal of wastewaters into sewers or into rivers, lakes or oceans. This applies to industries that generate wastewater with high concentrations of organic matter, toxic pollutants or nutrients such as ammonia. Some industries install a pre-treatment system to remove some pollutants, and then discharge the partially treated wastewater to the municipal sewer system.

Onsite sewage facilities (OSSF), also called septic systems, are wastewater systems designed to treat and dispose of effluent on the same property that produces the wastewater, in areas not served by public sewage infrastructure.

<span class="mw-page-title-main">Milorganite</span> Brand of biosolids fertilizer produced by treating sewage sludge

Milorganite is a brand of biosolids fertilizer produced by treating sewage sludge by the Milwaukee Metropolitan Sewerage District. The term is a portmanteau of the term Milwaukee Organic Nitrogen. The sewer system of the District collects municipal wastewater from the Milwaukee metropolitan area. After settling, wastewater is treated with microbes to break down organic matter at the Jones Island Water Reclamation Facility in Milwaukee, Wisconsin. The byproduct sewage sludge is produced. This is heat-dried with hot air in the range of 900–1,200 °F (482–649 °C), which heats the sewage sludge to at least 176 °F (80 °C) to kill pathogens. The material is then pelletized and marketed throughout the United States under the name Milorganite. The result is recycling of the nitrogen and phosphorus from the waste-stream as fertilizer. The treated wastewater is discharged to Lake Michigan.

<span class="mw-page-title-main">Sewage sludge treatment</span> Processes to manage and dispose of sludge during sewage treatment

Sewage sludge treatment describes the processes used to manage and dispose of sewage sludge produced during sewage treatment. Sludge treatment is focused on reducing sludge weight and volume to reduce transportation and disposal costs, and on reducing potential health risks of disposal options. Water removal is the primary means of weight and volume reduction, while pathogen destruction is frequently accomplished through heating during thermophilic digestion, composting, or incineration. The choice of a sludge treatment method depends on the volume of sludge generated, and comparison of treatment costs required for available disposal options. Air-drying and composting may be attractive to rural communities, while limited land availability may make aerobic digestion and mechanical dewatering preferable for cities, and economies of scale may encourage energy recovery alternatives in metropolitan areas.

<span class="mw-page-title-main">Sewage treatment</span> Process of removing contaminants from municipal wastewater

Sewage treatment is a type of wastewater treatment which aims to remove contaminants from sewage to produce an effluent that is suitable to discharge to the surrounding environment or an intended reuse application, thereby preventing water pollution from raw sewage discharges. Sewage contains wastewater from households and businesses and possibly pre-treated industrial wastewater. There are a high number of sewage treatment processes to choose from. These can range from decentralized systems to large centralized systems involving a network of pipes and pump stations which convey the sewage to a treatment plant. For cities that have a combined sewer, the sewers will also carry urban runoff (stormwater) to the sewage treatment plant. Sewage treatment often involves two main stages, called primary and secondary treatment, while advanced treatment also incorporates a tertiary treatment stage with polishing processes and nutrient removal. Secondary treatment can reduce organic matter from sewage,  using aerobic or anaerobic biological processes. A so-called quarternary treatment step can also be added for the removal of organic micropollutants, such as pharmaceuticals. This has been implemented in full-scale for example in Sweden.

<span class="mw-page-title-main">Sewage</span> Wastewater that is produced by a community of people

Sewage is a type of wastewater that is produced by a community of people. It is typically transported through a sewer system. Sewage consists of wastewater discharged from residences and from commercial, institutional and public facilities that exist in the locality. Sub-types of sewage are greywater and blackwater. Sewage also contains soaps and detergents. Food waste may be present from dishwashing, and food quantities may be increased where garbage disposal units are used. In regions where toilet paper is used rather than bidets, that paper is also added to the sewage. Sewage contains macro-pollutants and micro-pollutants, and may also incorporate some municipal solid waste and pollutants from industrial wastewater.

<span class="mw-page-title-main">Urban Waste Water Treatment Directive</span>

The Urban Waste Water Treatment Directive 1991 European Union directive concerning urban waste water "collection, treatment and discharge of urban waste water and the treatment and discharge of waste water from certain industrial sectors". It aims "to protect the environment from adverse effects of waste water discharges from cities and "certain industrial sectors". Council Directive 91/271/EEC on Urban Wastewater Treatment was adopted on 21 May 1991, amended by the Commission Directive 98/15/EC.

<span class="mw-page-title-main">Environmental persistent pharmaceutical pollutant</span> Environmental term

The term environmental persistent pharmaceutical pollutants (EPPP) was first suggested in the nomination in 2010 of pharmaceuticals and environment as an emerging issue in a Strategic Approach to International Chemicals Management (SAICM) by the International Society of Doctors for the Environment (ISDE). The occurring problems from EPPPs are in parallel explained under environmental impact of pharmaceuticals and personal care products (PPCP). The European Union summarizes pharmaceutical residues with the potential of contamination of water and soil together with other micropollutants under "priority substances".

<span class="mw-page-title-main">Sludge</span> Semi-solid slurry

Sludge is a semi-solid slurry that can be produced from a range of industrial processes, from water treatment, wastewater treatment or on-site sanitation systems. It can be produced as a settled suspension obtained from conventional drinking water treatment, as sewage sludge from wastewater treatment processes or as fecal sludge from pit latrines and septic tanks. The term is also sometimes used as a generic term for solids separated from suspension in a liquid; this soupy material usually contains significant quantities of interstitial water. Sludge can consist of a variety of particles, such as animal manure.

<span class="mw-page-title-main">Reuse of human excreta</span> Safe, beneficial use of human excreta mainly in agriculture (after treatment)

Reuse of human excreta is the safe, beneficial use of treated human excreta after applying suitable treatment steps and risk management approaches that are customized for the intended reuse application. Beneficial uses of the treated excreta may focus on using the plant-available nutrients that are contained in the treated excreta. They may also make use of the organic matter and energy contained in the excreta. To a lesser extent, reuse of the excreta's water content might also take place, although this is better known as water reclamation from municipal wastewater. The intended reuse applications for the nutrient content may include: soil conditioner or fertilizer in agriculture or horticultural activities. Other reuse applications, which focus more on the organic matter content of the excreta, include use as a fuel source or as an energy source in the form of biogas.

<span class="mw-page-title-main">Jacqui Horswell</span> Environmental microbiologist

Jacqueline Horswell is an English-born New Zealand environmental microbiologist who specialises in research into the waste society produces, its effect on the environment, and how it can be managed. Her work focuses particularly on measuring the effect of microbial and chemical contaminants in sewage sludge and the safe reuse of biosolids as fertilizer by the planting of native trees to filter and inactivate pollutants from the sludge and the use of vermiculture. Horswell is involved in consultation with communities in New Zealand and has contributed to official guidelines for the management of biosolids. Her research has also provided information about soil microbial communities for forensic science using microbial cultures and DNA sequencing. Since 2018, Horswell has been a lecturer at Massey University.

References

  1. 1 2 3 Tchobanoglous, George; Burton, Franklin L.; Stensel, H. David (2003). Wastewater engineering: treatment and reuse (4 ed.). Metcalf & Eddy. p. 1449. ISBN   978-0071122504.
  2. ↑ "The Sludge Hits the Fan". www.ejnet.org. Retrieved 2019-11-12.
  3. ↑ Stauber, John; Rampton, Sheldon (1995). Toxic Sludge Is Good for You: Lies, Damn Lies, and the Public Relations Industry. Common Courage Press. ISBN   1567510604.
  4. ↑ Richards, Brian K.; Peverly, John H.; Steenhuis, Tammo S.; Liebowitz, Barry N. (1997). "Effect of Processing Mode on Trace Elements in Dewatered Sludge Products". Journal of Environmental Quality. 26 (3): 782–8. doi:10.2134/jeq1997.00472425002600030027x.
  5. 1 2 Kelessidis and Stasinakis, 2012. COMPARATIVE STUDY OF THE METHODS USED FOR TREATMENT AND FINAL DISPOSAL OF SEWAGE SLUDGE IN EUROPEAN COUNTRIES, Waste Management, vol. 32, June 2012, p. 1186-1195. Kelessidis and Stasinakis, 2012
  6. ↑ "Branded products containing sewage sludge". Sludge News. 2007-11-30. Retrieved 16 January 2015.
  7. ↑ Wilce, Rebekah (9 May 2013). "Trade Group Offers Free Sewage Sludge "Compost" to Community Gardens in "Million Tomato Campaign" for Food Banks". PRWatch . Retrieved 16 January 2015.
  8. ↑ Biosolids Generation, Use, and Disposal in The United States (PDF) (Report). EPA. September 1999. p. 2. EPA530-R-99-009. Retrieved 30 May 2017.
  9. ↑ Lu, Qin; He, Zhenli H.; Stoffella, Peter J. (2012). Torri, Silvana I. (ed.). "Land Application of Biosolids in the USA: A Review". Applied and Environmental Soil Science. 2012: 4. doi: 10.1155/2012/201462 . 201462.
  10. ↑ Kelessidis and Stasinakis, 2012. COMPARATIVE STUDY OF THE METHODS USED FOR TREATMENT AND FINAL DISPOSAL OF SEWAGE SLUDGE IN EUROPEAN COUNTRIES. Waste Management, vol.32, June 2012, p. 1186-1195. Kelessidis and Stasinakis, 2012
  11. ↑ COMMISSION STAFF WORKING DOCUMENT EXECUTIVE SUMMARY OF THE EVALUATION Council Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture, 2023, retrieved 2024-10-18
  12. ↑ Kominko, Halyna; Gorazda, Katarzyna; Wzorek, Zbigniew (2024-06-01). "Sewage sludge: A review of its risks and circular raw material potential". Journal of Water Process Engineering. 63: 105522. doi:10.1016/j.jwpe.2024.105522. ISSN   2214-7144.
  13. ↑ Rieck, Christian; von Münch, Elisabeth; Hoffmann, Heike (December 2012). "Technology Review of Urine-diverting dry toilets (UDDTs)" (PDF). Susana . GIZ . Retrieved 5 June 2017.
  14. ↑ Graczyk, Thaddeus K.; Kacprzak, Malgorzata; Neczaj, Ewa; et al. (2008-01-01). "Occurrence of Cryptosporidium and Giardia in sewage sludge and solid waste landfill leachate and quantitative comparative analysis of sanitization treatments on pathogen inactivation". Environmental Research. 106 (1): 27–33. Bibcode:2008ER....106...27G. doi:10.1016/j.envres.2007.05.005. ISSN   0013-9351. PMID   17585898.
  15. ↑ Perkins, Tom (2024-03-01). "Texas farmers claim company sold them PFAS-contaminated sludge that killed livestock". The Guardian. ISSN   0261-3077 . Retrieved 2024-11-21.
  16. ↑ COMMISSION STAFF WORKING DOCUMENT EXECUTIVE SUMMARY OF THE EVALUATION Council Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture, 2023, retrieved 2024-10-18
  17. ↑ COMMISSION STAFF WORKING DOCUMENT EXECUTIVE SUMMARY OF THE EVALUATION Council Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture, 2023, retrieved 2024-10-18
  18. ↑ US EPA, OW (2015-07-10). "Learn about Ocean Dumping". US EPA. Retrieved 2019-11-12.
  19. ↑ US EPA, OA. "EPA History: Ocean Dumping Ban Act of 1988". archive.epa.gov. Retrieved 2022-01-12.
  20. ↑ Ingunza, Maria del Pilar Durante; Júnior, Olavo Francisco dos Santos; Medeiros, Sayonara Andrade (2013). Wu, Yun; Wu, Yijin (eds.). "Sewage Sludge as Raw-Material in Asphalt Mixtures". Advanced Materials Research. 664: 638–643. doi:10.4028/www.scientific.net/AMR.664.638. S2CID   137163083.
  21. ↑ Cartmell, Elise; Gostelow, Peter; Riddell-Black, Drusilla; et al. (2006). "Biosolids—A Fuel or a Waste? An Integrated Appraisal of Five Co-combustion Scenarios with Policy Analysis". Environmental Science & Technology. 40 (3): 649–58. Bibcode:2006EnST...40..649C. doi:10.1021/es052181g. PMID   16509299.
  22. ↑ COMMISSION STAFF WORKING DOCUMENT EXECUTIVE SUMMARY OF THE EVALUATION Council Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture, 2023, retrieved 2024-10-18
  23. 1 2 Harrison, Ellen Z.; Oakes, Summer Rayne (2003). "Investigation of alleged health incidents associated with land application of sewage sludges". New Solutions. 12 (4): 387–408. Bibcode:2003NewSo..12..387H. doi:10.2190/0FJ0-T6HJ-08EM-HWW8. hdl: 1813/5319 . PMID   17208785. S2CID   26931475.
  24. ↑ Hosseinpur, Alireza; Pashamokhtari, Hamed (2013). "The effects of incubation on phosphorus desorption properties, phosphorus availability, and salinity of biosolids-amended soils". Environmental Earth Sciences . 69 (3): 899–908. Bibcode:2013EES....69..899H. doi:10.1007/s12665-012-1975-6. S2CID   140537340.
  25. ↑ Artiola, Janick F. (November 2006). "Biosolids land use in Arizona" (PDF). University of Arizona . Archived from the original (PDF) on 9 March 2008. Retrieved 2 June 2017.
  26. ↑ McBride, Murray B.; Richards, Brian K.; Steenhuis, Tammo S.; Spiers, G. (May–June 2000). "Molybdenum Uptake by Forage Crops Grown on Sewage Sludge-Amended Soils in the Field and Greenhouse" (PDF). Journal of Environmental Quality . 29 (3): 848–54. Bibcode:2000JEnvQ..29..848M. doi:10.2134/jeq2000.00472425002900030021x . Retrieved 2 June 2017.
  27. ↑ Kim, Bojeong; McBride, Murray B.; Richards, Brian K.; Steenhuis, Tammo S. (2007). "The long-term effect of sludge application on Cu, Zn, and Mo behavior in soils and accumulation in soybean seeds". Plant and Soil. 299 (1–2): 227–36. doi:10.1007/s11104-007-9377-3. S2CID   24692709.
  28. ↑ McBride, Murray B. (2005). "Molybdenum and Copper Uptake by Forage Grasses and Legumes Grown on a Metal-Contaminated Sludge Site". Communications in Soil Science and Plant Analysis. 36 (17–18): 2489–501. doi:10.1080/00103620500255840. S2CID   98655719.
  29. ↑ Bulegoa, Komunikazio (8 January 2009). "Adding high doses of sludge to neutralize soil acidity not advisable". Basque Research. Retrieved 2 June 2017.
  30. 1 2 Edwards, M.; Topp, E.; Metcalfe, CD.; et al. (1 July 2009). "Pharmaceutical and personal care products in tile drainage following surface spreading and injection of dewatered municipal biosolids to an agricultural field". Science of the Total Environment . 407 (14): 4220–30. Bibcode:2009ScTEn.407.4220E. doi:10.1016/j.scitotenv.2009.02.028. PMID   19394680.
  31. 1 2 Xia, Kang; Hundal, Lakhwinder S.; Kumar, Kuldip; et al. (2010). "Triclocarban, triclosan, polybrominated diphenyl ethers, and 4-nonylphenol in biosolids and in soil receiving 33-year biosolids application". Environmental Toxicology and Chemistry. 29 (3): 597–605. doi: 10.1002/etc.66 . PMID   20821484. S2CID   8455892.
  32. ↑ Cha, Jongmun; Cupples, Alison M. (2009). "Detection of the antimicrobials triclocarban and triclosan in agricultural soils following land application of municipal biosolids". Water Research. 43 (9): 2522–30. Bibcode:2009WatRe..43.2522C. doi:10.1016/j.watres.2009.03.004. PMID   19327812.
  33. ↑ Cha, Jongmun; Cupples, Alison M. (2010). "Triclocarban and triclosan biodegradation at field concentrations and the resulting leaching potentials in three agricultural soils". Chemosphere. 81 (4): 494–9. Bibcode:2010Chmsp..81..494C. doi:10.1016/j.chemosphere.2010.07.040. PMID   20705327.
  34. ↑ Wu, Chenxi; Spongberg, Alison L.; Witter, Jason D.; et al. (2010). "Uptake of Pharmaceutical and Personal Care Products by Soybean Plants from Soils Applied with Biosolids and Irrigated with Contaminated Water". Environmental Science & Technology. 44 (16): 6157–61. Bibcode:2010EnST...44.6157W. doi:10.1021/es1011115. PMID   20704212.
  35. ↑ Harrison, Ellen Z.; McBride, Murray B.; Bouldin, David R. (1999). "Land application of sewage sludges: An appraisal of the US regulations". International Journal of Environment and Pollution. 11: 1–36. doi:10.1504/IJEP.1999.002247. hdl: 1813/5299 .
  36. 1 2 Harrison, Ellen Z; McBride, Murray (March 2009). "Case for Caution Revisited: Health and Environmental Impacts of Application of Sewage Sludges to Agricultural Land" (PDF). Cornell Waste Management Institute. Retrieved 16 January 2016.
  37. ↑ Barker, Allen; Harrison, Ellen; Hay, Anthony; et al. (April 2007). "Guidelines for Application of Sewage Biosolids to Agricultural Lands in the Northeastern U.S." (PDF). Cornell University . Retrieved 2 June 2017.
  38. ↑ "Understanding Organic Food Labels, Benefits, and Claims". HelpGuide. Archived from the original on 9 January 2012. Retrieved 2 June 2017.
  39. ↑ "Whole Foods Draws A Line In The Sludge". Food Republic. 23 January 2014. Retrieved 26 February 2017.
  40. ↑ Barclay, Eliza (21 January 2014). "Whole Foods Bans Produce Grown With Sludge. But Who Wins?". NPR . Retrieved 26 February 2017.
  41. ↑ Guangwei, He (7 July 2014). "In China's Heartland, A Toxic Trail Leads from Factories to Fields to Food". Yale Environment 360 . Retrieved 5 June 2017.
  42. ↑ Reid, Andy (21 December 2015). "Sewage sludge prompts outrage". PressReader . Sun Sentinel . Retrieved 5 June 2017.
  43. ↑ Godfrey, Miles (7 August 2008). "Outrage as 'Poohaven' sewage plant is approved". The Argus . Retrieved 5 June 2017.
  44. ↑ Richardson, Jill (4 March 2010). "Outrage in San Francisco: City Gives Residents 'Organic' Compost Containing Toxic Sewage Sludge". AlterNet . Retrieved 5 June 2017.
  45. ↑ COMMISSION STAFF WORKING DOCUMENT EXECUTIVE SUMMARY OF THE EVALUATION Council Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture, 2023, retrieved 2024-10-18
  46. ↑ COMMISSION STAFF WORKING DOCUMENT EXECUTIVE SUMMARY OF THE EVALUATION Council Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture, 2023, retrieved 2024-10-18
  47. ↑ Zorpas, Antonis A. (2012). "Contribution of Zeolites in Sewage Sludge Composting". In Inglezakis, Vassilis J.; Zorpas, Antonis A. (eds.). Handbook of Natural Zeolites. Bentham Science. p. 289. ISBN   978-1-60805-446-6.
  48. 1 2 3 4 Bagheri, Marzieh; Bauer, Torben; Burgman, Linus Ekman; Wetterlund, Elisabeth (2023). "Fifty years of sewage sludge management research: Mapping researchers' motivations and concerns". Journal of Environmental Management. 325 (Pt A): 116412. doi:10.1016/j.jenvman.2022.116412. ISSN   0301-4797. PMID   36274309.
  49. ↑ Sims, J. Thomas; Sharpley, Andrew N., eds. (2005). Phosphorus: Agriculture and the Environment. ASA, SSSA, CSSA. ISBN   978-0-89118-269-6 . Retrieved 5 June 2017.
  50. ↑ Morgenschweis, Christa. "Phosphorus recovery with Pearl technology". Grontmij . Archived from the original on 18 March 2016. Retrieved 5 June 2017.
  51. ↑ COMMISSION STAFF WORKING DOCUMENT EXECUTIVE SUMMARY OF THE EVALUATION Council Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture, 2023, retrieved 2024-10-18
  52. ↑ Jolis, Domènec (April 2006). "Regrowth of fecal coliforms in class A biosolids". Water Environment Research. 78 (4): 442–5. Bibcode:2006WaEnR..78..442J. doi:10.2175/106143005X90074. PMID   16749313. S2CID   21071021.
  53. ↑ Lewis, David L.; Gattie, David K. (July 2002). "Pathogen Risks From Applying Sewage Sludge to Land". Environmental Science & Technology . 36 (13): 286A–293A. doi:10.1021/es0223426. PMID   12144261.
  54. ↑ Harrison, Ellen Z.; Oakes, Summer Rayne (2003). "Investigation of alleged health incidents associated with land application of sewage sludges" (PDF). New Solutions. 12 (4): 387–408. Bibcode:2003NewSo..12..387H. doi:10.2190/0FJ0-T6HJ-08EM-HWW8. hdl: 1813/5319 . PMID   17208785. S2CID   26931475 . Retrieved 30 May 2017.
  55. ↑ McBride, Murray B. (October 2003). "Toxic metals in sewage sludge-amended soils: Has promotion of beneficial use discounted the risks?". Advances in Environmental Research. 8: 5–19. doi:10.1016/S1093-0191(02)00141-7 . Retrieved 30 May 2017.
  56. ↑ Turek, Marian; Korolewicz, Teofil; Ciba, Jerzy (2005). "Removal of Heavy Metals from Sewage Sludge Used as Soil Fertilizer". Soil and Sediment Contamination. 14 (2): 143–54. Bibcode:2005SSCIJ..14..143T. doi:10.1080/15320380590911797. S2CID   93258156.
  57. 1 2 "Targeted National Sewage Sludge Survey Statistical Analysis Report" (PDF). EPA. January 2009. EPA-822-R-08-018. Archived from the original (PDF) on 11 July 2009. Retrieved 6 August 2009.
  58. 1 2 "Biosolids: Targeted National Sewage Sludge Survey Report — Overview". EPA . January 2009. EPA 822-R-08-014. Archived from the original on 16 February 2015. Retrieved 12 January 2015.
  59. ↑ Stasinakis et al., 2013. Contribution of primary and secondary treatment on the removal of benzothiazoles, benzotriazoles, endocrine disruptors, pharmaceuticals and perfluorinated compounds in a sewage treatment plant. Sci. Total Environ. vol.463-464, October 2013, p. 1067-1075. Stasinakis et al., 2013
  60. ↑ Arvaniti and Stasinakis, 2015. Review on the occurrence, fate and removal of perfluorinated compounds during wastewater treatment. Sci. Total Environ. vol. 524-525, August 2015, p. 81-92. Arvaniti and Stasinakis, 2015
  61. ↑ Henry, Christopher (January 2005). "Understanding Biosolids" (PDF). University of Washington . Archived from the original (PDF) on 21 February 2012. Retrieved 1 June 2017.
  62. ↑ "Household Chemicals and Drugs Found in Biosolids from Wastewater Treatment Plants". United States Geological Survey . 16 November 2016. Retrieved 1 June 2017.
  63. ↑ Plowden, Mark (25 September 2013). "DHEC Issues Emergency Regulation, Expands Investigation into PCBs Found at Water Treatment Plants". SCDHEC . Archived from the original on 26 September 2013. Retrieved 1 June 2017.
  64. ↑ "Emergency Regulation for Management of Wastewater System Sludge" (PDF). SCDHEC . 25 October 2013. Retrieved 1 June 2017.
  65. ↑ Henderson, Bruce (14 April 2014). "Charlotte PCB cleanup costs to top $1.3 million". The Charlotte Observer . Retrieved 1 June 2017.
  66. ↑ Henderson, Bruce; Lyttle, Steve; Bethea, April (7 February 2014). "Task force named to probe chemical dumping". The Charlotte Observer . Retrieved 1 June 2017.
  67. ↑ "Toxic 'Risk Assessment of Pollutants in Biosolids". EPA. 26 February 2020. Retrieved 28 March 2022.
  68. ↑ Zubris, Kimberly Ann V.; Richards, Brian K. (2005). "Synthetic fibers as an indicator of land application of sludge". Environmental Pollution. 138 (2): 201–11. Bibcode:2005EPoll.138..201Z. doi:10.1016/j.envpol.2005.04.013. PMID   15967553.
  69. ↑ "503.9" (PDF). Code of Federal Regulations. GPO (Report). Vol. 40. Retrieved 1 June 2017.
  70. ↑ Jerving, Sara (18 March 2012). "New Toxic Sludge PR and Lobbying Effort Gets Underway". CommonDreams. PRWatch. Retrieved 2 June 2017.
  71. ↑ Biosolids Applied to Land: Advancing Standards and Practices. Washington, DC: National Academy of Sciences. 2002. doi:10.17226/10426. ISBN   978-0-309-57036-7.
  72. ↑ "Use and Disposal of Biosolids". EPA . 2016-11-08. Archived from the original on 26 March 2008. Retrieved 5 June 2017.
  73. ↑ Douwes, J.; Thorne, P; Pearce, N; Heederik, D (2003). "Bioaerosol Health Effects and Exposure Assessment: Progress and Prospects". Annals of Occupational Hygiene. 47 (3): 187–200. doi: 10.1093/annhyg/meg032 . PMID   12639832.
  74. ↑ Lewis, David L; Gattie, David K; Novak, Marc E; et al. (2002). "Interactions of pathogens and irritant chemicals in land-applied sewage sludges (biosolids)". BMC Public Health. 2: 11. doi: 10.1186/1471-2458-2-11 . PMC   117218 . PMID   12097151.
  75. 1 2 Khuder, Sadik; Milz, Sheryl A.; Bisesi, Michael; et al. (2007). "Health Survey of Residents Living Near Farm Fields Permitted to Receive Biosolids". Archives of Environmental & Occupational Health. 62 (1): 5–11. Bibcode:2007ArEOH..62....5K. CiteSeerX   10.1.1.534.8483 . doi:10.3200/AEOH.62.1.5-11. PMID   18171641. S2CID   14867023.
  76. ↑ "Human Health Risk". Sludge Victims. Archived from the original on 4 March 2016. Retrieved 5 June 2017.
  77. ↑ Heilprin, John (2008-04-14). "Sludge tested as lead protection in poor areas". Boston.com. Retrieved 2018-10-26.
  78. ↑ Perkins, Tom (22 March 2022). "'I don't know how we'll survive': the farmers facing ruin in America's 'forever chemicals' crisis". The Guardian. Guardian News & Media Limited. Retrieved 28 March 2022.
  79. ↑ "Toxic 'forever chemicals' found in Michigan farm's beef". abcNEWS. ABC News Internet Ventures. Retrieved 28 March 2022.
  80. ↑ "PFAS Strategic Roadmap: EPA's Commitments to Action 2021-2024". EPA. 14 October 2021. Retrieved 2022-03-24.
  81. ↑ Kelessidis, Alexandros; Stasinakis, Athanasios S. (June 2012). "Comparative study of the methods used for treatment and final disposal of sewage sludge in European countries". Waste Management (New York, N.Y.). 32 (6): 1186–1195. Bibcode:2012WaMan..32.1186K. doi:10.1016/j.wasman.2012.01.012. ISSN   1879-2456. PMID   22336390.
  82. ↑ Martínez, K.; Abad, E.; Palacios, O.; et al. (2007-11-01). "Assessment of polychlorinated dibenzo-p-dioxins and dibenzofurans in sludges according to the European environmental policy". Environment International. 33 (8): 1040–1047. Bibcode:2007EnInt..33.1040M. doi:10.1016/j.envint.2007.06.005. ISSN   0160-4120. PMID   17698193.
  83. ↑ "Sewage sludge - Waste - Environment - European Commission". ec.europa.eu. Retrieved 2019-11-19.
  84. 1 2 Council Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture, vol. OJ L, 1986-07-04, retrieved 2019-11-19
  85. 1 2 3 " Disposal and Recycling Routes for Sewage Sludge" Part 2 - Regulatory report October 2001. pg 1-65. Written by the EU Directive General for the Environment under the European commission. https://ec.europa.eu/environment/archives/waste/sludge/pdf/sludge_disposal2.pdf
  86. ↑ Council Directive of 12 June 1986 on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture (86/278/EEC) , retrieved 2024-10-17
  87. 1 2 3 "Using sewage sludge in farming | EUR-Lex". eur-lex.europa.eu. Retrieved 2024-10-17.
  88. ↑ COMMISSION STAFF WORKING DOCUMENT EXECUTIVE SUMMARY OF THE EVALUATION Council Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture, 2023, retrieved 2024-10-18
  89. 1 2 Gianico, Andrea; Braguglia, Camilla; Gallipoli, Agata; Montecchio, Daniele; Mininni, Giuseppe (2021). "Land Application of Biosolids in Europe: Possibilities, Con-Straints and Future Perspectives". Water. 13 (1): 103. doi: 10.3390/w13010103 . ISSN   2073-4441.
  90. ↑ "Using sewage sludge in farming | EUR-Lex". eur-lex.europa.eu. Retrieved 2024-10-17.
  91. 1 2 Verlicchi, P.; Zambello, E. (2015-12-15). "Pharmaceuticals and personal care products in untreated and treated sewage sludge: Occurrence and environmental risk in the case of application on soil — A critical review". Science of the Total Environment. 538: 750–767. doi:10.1016/j.scitotenv.2015.08.108. hdl:11392/2335213. ISSN   0048-9697. PMID   26327643.
  92. ↑ COMMISSION STAFF WORKING DOCUMENT EXECUTIVE SUMMARY OF THE EVALUATION Council Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture, 2023, retrieved 2024-10-18
  93. 1 2 3 Gianico, Andrea; Braguglia, Camilla; Gallipoli, Agata; Montecchio, Daniele; Mininni, Giuseppe (2021). "Land Application of Biosolids in Europe: Possibilities, Con-Straints and Future Perspectives". Water. 13 (1): 103. doi: 10.3390/w13010103 . ISSN   2073-4441.
  94. ↑ "Ex-post evaluation of certain waste stream Directives: Final Report" (PDF). European Commission - DG Environment. 2014-04-18. Retrieved 2024-10-19.
  95. 1 2 Gianico, Andrea; Braguglia, Camilla; Gallipoli, Agata; Montecchio, Daniele; Mininni, Giuseppe (2021). "Land Application of Biosolids in Europe: Possibilities, Con-Straints and Future Perspectives". Water. 13 (1): 103. doi: 10.3390/w13010103 . ISSN   2073-4441.
  96. ↑ COMMISSION STAFF WORKING DOCUMENT EXECUTIVE SUMMARY OF THE EVALUATION Council Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture, 2023, retrieved 2024-10-18
  97. ↑ "Ex-post evaluation of certain waste stream Directives: Final Report" (PDF). European Commission - DG Environment. 2014-04-18. Retrieved 2024-10-19.
  98. 1 2 Gianico, Andrea; Braguglia, Camilla; Gallipoli, Agata; Montecchio, Daniele; Mininni, Giuseppe (2021). "Land Application of Biosolids in Europe: Possibilities, Con-Straints and Future Perspectives". Water. 13 (1): 103. doi: 10.3390/w13010103 . ISSN   2073-4441.
  99. 1 2 "Circular economy action plan - European Commission". environment.ec.europa.eu. Retrieved 2024-10-18.
  100. ↑ "Ex-post evaluation of certain waste stream Directives: Final Report" (PDF). European Commission - DG Environment. 2014-04-18. Retrieved 2024-10-19.
  101. 1 2 3 COMMISSION STAFF WORKING DOCUMENT EXECUTIVE SUMMARY OF THE EVALUATION Council Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture, 2023, retrieved 2024-10-18
  102. ↑ "Sewage sludge - European Commission". environment.ec.europa.eu. 2024-09-27. Retrieved 2024-10-18.
  103. ↑ COMMISSION STAFF WORKING DOCUMENT EXECUTIVE SUMMARY OF THE EVALUATION Council Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture, 2023, retrieved 2024-10-18
  104. 1 2 Verlicchi, P.; Zambello, E. (2015-12-15). "Pharmaceuticals and personal care products in untreated and treated sewage sludge: Occurrence and environmental risk in the case of application on soil — A critical review". Science of the Total Environment. 538: 750–767. doi:10.1016/j.scitotenv.2015.08.108. hdl:11392/2335213. ISSN   0048-9697. PMID   26327643.
  105. ↑ Gianico, Andrea; Braguglia, Camilla; Gallipoli, Agata; Montecchio, Daniele; Mininni, Giuseppe (2021). "Land Application of Biosolids in Europe: Possibilities, Con-Straints and Future Perspectives". Water. 13 (1): 103. doi: 10.3390/w13010103 . ISSN   2073-4441.
  106. ↑ "A Plain English Guide to the EPA Part 503 Biosolids Rule" (PDF). EPA . September 1994. Retrieved 5 June 2017.
  107. 1 2 3 U.S. Environmental Protection Agency Office of Inspector General. (2018-11-15). EPA Unable to Assess the Impact of Hundreds of Unregulated Pollutants in Land-Applied Biosolids on Human Health and the Environment. Report No. 19-P-0002.
  108. 1 2 3 Popoola, Lekan Taofeek; Olawale, Theophilus Ogunwumi; Salami, Lukumon (2023). "A review on the fate and effects of contaminants in biosolids applied on land: Hazards and government regulatory policies". Heliyon. 9 (10): e19788. doi: 10.1016/j.heliyon.2023.e19788 . ISSN   2405-8440. PMC   10556614 . PMID   37810801.
  109. 1 2 3 4 Lu, Qin; He, Zhenli L.; Stoffella, Peter J. (2012). "Land Application of Biosolids in the USA: A Review". Applied and Environmental Soil Science. 2012: 1–11. doi: 10.1155/2012/201462 . ISSN   1687-7667.
  110. ↑ "Pharmaceutical waste management". Premier. Archived from the original on 25 May 2007. Retrieved 30 May 2017.
  111. ↑ Boyd, John (26 August 2011). "Radioactive Sludge Collects in Japan's Sewage Treatment Plants". IEEE . Retrieved 30 May 2017.
  112. ↑ "Processes to Further Reduce Pathogens (PFRPs)" (PDF). EPA . Archived from the original (PDF) on 6 March 2009. Retrieved 5 June 2017.
  113. ↑ "Title 40 - Protection of Environment". GPO . Retrieved 5 June 2017.
  114. ↑ "Land Application of Biosolids" (PDF). EPA . 28 March 2002. Retrieved 5 June 2017.
  115. ↑ "Questions and Answers on the Part 503 Risk Assessments" (PDF). EPA . 2014-04-23. Archived from the original (PDF) on 3 November 2014. Retrieved 5 June 2017.
  116. ↑ "Former Synagro Executive guilty of bribing City officials".
  117. ↑ "Synagro Bribe Caught on FBI Tape".
  118. ↑ "Travis County - Sludge violates local ordinances" (PDF).
  119. ↑ "Los Angeles and Kern County's Epic Sewage Sludge Battle". PR Watch. 2011-10-05. Retrieved 2018-10-26.
  120. ↑ "Court Reaches Verdict in Los Angeles County Vs. Kern County Case". Waste360. 2016-12-08. Retrieved 2023-02-15.
  121. ↑ "City of L.A. Secures Trial Decision Striking Down Kern County Biosolids Ban | Department of Public Works". dpw.lacity.org. Retrieved 2023-02-15.
  122. ↑ Writer, D.E. SmootPhoenix Staff. "Landowners win sludge suit". Muskogee Phoenix. Retrieved 2018-10-26.
  123. ↑ "Gilbert_v_synagro lawsuit" (PDF).
  124. ↑ Swanson, R. Lawrence; Bortman, Marci L.; O'Connor, Thomas P.; Stanford, Harold M. (November 2004). "Science, policy and the management of sewage materials. The New York City experience". Marine Pollution Bulletin. 49 (9–10): 679–687. Bibcode:2004MarPB..49..679S. doi:10.1016/j.marpolbul.2004.06.025. PMID   15530510.

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