Last Week Was the Fourth-Largest U.S. Natural Gas Storage Withdrawal on Record

     According to the Energy Information Administration the week ending January 29, 2025, was the fourth largest withdrawal ever from natural gas storage at 321 billion cubic feet (BCF). As I noted in a previous post, PJM Interconnection had its highest power demand day ever on January 22, with natural gas being responsible for 42.5% of that power demand. According to the EIA:

“Net withdrawals from storage totaled 321 Bcf for the week ending January 24, compared with the five-year (2020–24) average net withdrawals of 189 Bcf and last year's net withdrawals of 234 Bcf during the same week. This is the fourth-largest withdrawal on record.”

Gas supply is steady and easily supplying domestic needs as well as export, with far fewer rigs drilling as shown in the rig counts below. In January 2019 there were about 1000 rigs drilling. Last week there were just 571 rigs drilling, producing about 15-20BCF/day more gas than in 2019.  

 

References:

 

Natural Gas Weekly Update. for week ending January 29, 2025   |  Release date:  January 30, 2025. EIA. Natural Gas Weekly Update

 

 

 

PJM Interconnection Experiences Highest Electricity Demand Ever: Fossil Fuels and Nuclear Provide 92.9% of the Power Needed

     On January 22, PJM Interconnection experienced its highest electricity demand ever with limited interruptions. Natural gas provided 42.5%, coal 22.9%, oil 3%, nuclear 24.5%, and wind and solar combined 4.46%. The other 7.1% was provided mostly by biomass and hydro, presumably. 68.4% was provided by fossil fuels and 92.9% by fossil fuels plus nuclear. If we add biomass, then about 95% of that power was provided through combustion plus splitting atoms and about 70% was provided by combustion alone. When Bill McKibben says we need to stop burning things, perhaps he doesn’t understand the level at which ‘burning things’ sustains us by providing power and heat. The 70% of power provided by combustion is just power. If we add direct heating through natural gas and wood, then combustion wins the day by far. We probably can and should reduce combustion, but it is simply a ridiculous statement that we should eliminate combustion.  

 

References:

 

PJM Grid Sees Biggest Demand EVER, NatGas & Coal Saved the Day. Marcellus Drilling News. January 23. 2025. PJM Grid Sees Biggest Demand EVER, NatGas & Coal Saved the Day | Marcellus Drilling News

Ammonia Air Pollution from Agriculture: Volatilization from Manure Lagoons and Fertilizer

     Ammonia is a gas (NH3) and a common pollutant from landfills, sewage treatment plants, and livestock agriculture operations.  Other sources include crop agriculture from the volatilization of nitrogen fertilizer, wildfires, car exhaust, human waste, industry, and natural sources such as decomposition in the ocean. In plant and animal agriculture the ammonium (NH4) in solution from fertilizer or livestock waste is volatilized into ammonia and hydrogen. Once volatized into gaseous form it becomes mobile and is released into the atmosphere. The table below shows the sources of ammonia pollution globally. Agriculture is responsible for over 70% of global ammonia emissions. About 47% of the total is from livestock agriculture, and 23% of the total is from fertilizer volatilization.  Two-thirds of agricultural ammonia emissions come from livestock agriculture and one-third from crop agriculture.

Natural and Anthropogenic Ammonia Emissions. Source: Wikipedia

Ammonia is one of those chemicals that can be beneficial or detrimental. Like methane, it can be used to provide power as it releases its hydrogen, either through combustion or fuel cells. That, of course, requires concentrated pure ammonia that is produced chemically. The sources of ammonia in crop agriculture are non-point sources. Landfills can capture it if they are equipped to capture gas. Manure and urine collection ponds can be outfitted to recover methane, ammonia, and other anaerobic decomposition gases.

     A 2024 paper in Nature Sustainability explores the economic and environmental benefits of ammonia recovery alongside the recovery of hydrogen for fuel and hydrogen peroxide (H2O2). The researchers developed an electrode to oxidize organic matter which also chemically uptakes ammonium and potassium ions. The abstract of the paper explains it. The graphs are from the paper.

Abstract

“Livestock manure wastewater, containing high levels of ammonia, is a major source of water contamination, posing serious threats to aquatic ecosystems. Because ammonia is an important nitrogen fertilizer, efficiently recovering ammonia from manure wastewater would have multiple sustainability gains from both the pollution control and the resource recovery perspectives. Here we develop an electrochemical strategy to achieve this goal by using an ion-selective potassium nickel hexacyanoferrate (KNiHCF) electrode as a mediator. The KNiHCF electrode spontaneously oxidizes organic matter and uptakes ammonium ions (NH4+) and potassium ions (K+) in manure wastewater with a nutrient selectivity of ∼100%. Subsequently, nitrogen- and potassium-rich fertilizers are produced alongside the electrosynthesis of H2 (green fuel) or H2O2 (disinfectant) while regenerating the KNiHCF electrode. The preliminary techno-economic analysis indicates that the proposed strategy has notable economic potential and environmental benefits. This work provides a powerful strategy for efficient nutrient (NH4+ and K+) recovery and decentralized fertilizer and chemical production from manure wastewater, paving the way to sustainable agriculture.”

 

     A 2019 study in the U.K. by the Bureau of Investigative Journalism found that the country on;ly monitors ammonia air pollution from the largest intensive poultry and pig farms, but not from cow and dairy farms which produce far more ammonia. It’s also true, however, that those intensive, more confined operations can produce more ammonia pollution over a small local area.

     Gaseous ammonia contributes significantly to particulate matter pollution, particularly the most dangerous smaller form, PM2.5. The investigation explains:

“Ammonia travels on the wind and can mix with industrial and car fumes, creating a form of “particulate matter”, PM 2.5, that has been linked to higher death rates, respiratory problems, cardiovascular diseases, cognitive decline and low birth weights.”

“PM2.5 is probably responsible for somewhere between half and three quarters of the total harm we derive as humans from air pollution,” said Alastair Lewis, a professor of atmospheric chemistry at the National Centre for Atmospheric Science. He said about half of PM2.5 in urban areas is associated with ammonia.”

     The graphs below are from the investigation showing fate and transport, human health effects, UK data, and UK ammonia hotspots.

     A 2011 paper in Agriculture, Ecosystems & Environment investigated ammonia pollution generation and mitigation from pig houses.

“The main factors influencing NH3 production are the floor type, the manure removal system, the climatic conditions inside the building, the diet composition and the feed efficiency of animals.”

     More bedding is associated with less ammonia production. Lower crude protein diets, higher fiber diets, and additives can lower ammonia emissions.  

“The reduction of the slurry pit surface thanks to sloped pit walls are related to proportional reductions of NH3 emissions. Frequent manure removal, flushing and separating urine from faeces by V-shaped scraper or conveyor belts reduce the NH3 releases from the buildings by about 50%. However, the emissions during the storage period outside the building have to be taken into account for a whole assessment of the technique.”

     Ammonia emissions are also affected by ambient temperature and ventilation conditions.

     A 2025 paper in Environmental Science and Technology led by researchers from the University of Virginia explored environmental justice issues around ammonia pollution from pig farms in Eastern North Carolina. The paper concludes that minority communities are being disproportionately polluted by those operations.

“Concentrated animal feeding operations (CAFOs) emit various harmful and noxious air pollutants, including ammonia (NH3). There are limited measurements of CAFO-related air quality, contributing to disputes around its severity. We use NH3 vertical column densities from the space-based Infrared Atmospheric Sounding Interferometer (IASI) to report systematic, distributive inequalities in NH3 column enhancements (ΔNH3 columns), equal to NH3 columns less an observationally determined tropospheric background. Population-weighted block group-scale ΔNH3 columns are higher by 27 ± 3% for Black and African Americans, 35 ± 3% for Hispanics and Latinos, and 49 ± 3% for American Indians compared to non-Hispanic/Latino whites in Eastern North Carolina (April–August 2016–2021).”

"The satellite ammonia measurements are independent, observational evidence of inequalities in the air pollution impacts of industrial swine operations across Eastern North Carolina," said Pusede. "The satellite measurements are consistent with residents' claims of unfair and unaddressed air quality issues and highlight the urgent need for regulatory action."

 

 

References:

 

Deadly gas: Cutting farm emissions in half could save 3,000 lives a year. The Bureau of Investigative Journalism. Andrew Wasley, Alexandra Heal, and Mie Lainio. June 13, 2019. Deadly gas: Cutting farm emissions in half could save 3,000… | TBIJ

Air pollution inequities linked to industrial swine facilities are detectable from space. Science X staff. Phys.org. January 28, 2025. Air pollution inequities linked to industrial swine facilities are detectable from space

Ammonia emissions from pig houses: Influencing factors and mitigation techniques. François-Xavier Philippe, Jean-François Cabaraux, and Baudouin Nicks. Agriculture, Ecosystems & Environment. Volume 141, Issues 3–4, May 2011, Pages 245-260. Ammonia emissions from pig houses: Influencing factors and mitigation techniques - ScienceDirect

Ammonia pollution. Wikipedia. Ammonia pollution - Wikipedia

Electrochemical ammonia recovery and co-production of chemicals from manure wastewater. Rui Wang, Kai Yang, Cindy Wong, Horacio Aguirre-Villegas, Rebecca Larson, Fikile Brushett, Mohan Qin & Song Jin. Nature Sustainability volume 7, pages179–190 (2024). Electrochemical ammonia recovery and co-production of chemicals from manure wastewater | Nature Sustainability

Satellite Observations of Atmospheric Ammonia Inequalities Associated with Industrialized Swine Facilities in Eastern North Carolina. Akirah Epps, Isabella M. Dressel, Xuehui Guo, Maghogho Odanibe, Kimberly P. Fields, Ann Marie G. Carlton, Kang Sun, and Sally E. Pusede. Environmental Science & Technology. 2025. Satellite Observations of Atmospheric Ammonia Inequalities Associated with Industrialized Swine Facilities in Eastern North Carolina | Environmental Science & Technology

Air Pollution from Landfills, Anaerobic Digesters, and Other Biogas Plants: Biogas Impurities and Processing Improvements

     Raw or unprocessed biogas contains pollutants that are released both before and after combustion. The common components of biogas are methane, CO2, O2, N2, H2, and H2S with smaller amounts of other contaminants such as sulfur compounds, ammonia, and siloxanes. Burning unprocessed biogas creates significant air pollution. The contaminants are explained below by Wikipedia in terms of pre- and post-combustion dangers.

Sulfur compounds

“Toxic, corrosive and foul smelling hydrogen sulfide (H2S) is the most common contaminant in biogas. If not separated, combustion will produce sulfur dioxide (SO2) and sulfuric acid (H2SO4), which are corrosive and environmentally hazardous, Other sulfur-containing compounds, such as thiols may be present.

Ammonia

“Ammonia (NH3) is produced from organic compounds containing nitrogen, such as the amino acids in proteins. If not separated from the biogas, combustion results in NOx emissions.

Siloxanes

“In some cases, biogas contains siloxanes. They are formed from the anaerobic decomposition of materials commonly found in soaps and detergents. During combustion of biogas containing siloxanes, silicon is released and can combine with free oxygen or other elements in the combustion gas. Deposits are formed containing mostly silica (SiO2) or silicates (SixOy) and can contain calcium, sulfur, zinc, phosphorus. Such white mineral deposits accumulate to a surface thickness of several millimeters and must be removed by chemical or mechanical means.

“Practical and cost-effective technologies to remove siloxanes and other biogas contaminants are available.

Other important contaminants in biogas include volatile organic compounds (VOCs) and terpenes. These five: sulfur compounds like H2S, siloxane, ammonia, VOCs, and terpenes are the main biogas contaminants.

 

Anaerobic Digesters

     Anaerobic digestion is a good way to capture methane and fertilizer from waste. Agricultural waste, food waste, and yard waste can be used as feedstock. Manure is often a component of the feedstock and may be added to hasten the process. Anaerobic digestors still produce air pollutants including carbon monoxide (CO), nitrogen oxides (NOx), and sulfur dioxide (SO2). The resultant gas also produces more formaldehyde than other fuel sources when burned. Other potential environmental issues with anaerobic digesters (ADs) include the risk of spills, the need for significant transport of wastes, and nuisance odors.

Anaerobic Digester. Source: Power Knot

     Operators of AD facilities must acquire air quality permits before construction. These must consider the current quality of local air to determine if additions will approach or exceed pollutant limits. Dispersal of pollution must also be considered which takes into account weather data such as prevailing winds. Regulators acquire comparable data on AD facilities with stack tests that measure emissions and pollutant level predictions for comparable facilities.

 

Biogas Processing and Improvements

     A 2023 paper in Biogas Production and Process Control Improvements addresses process control improvements which refers to the whole of the biogas collection and generating process. The authors state some basic data and facts about biogas and some interesting conclusions about the state of biogas generation as a science. The abstract is below.

Abstract

“Biogas is a sustainable energy produced from biodegradable organic matter through anaerobic digestion. Biogas mainly contains methane (CH4) and carbon dioxide (CO2) and various contaminants, such as water vapor (H2O), ammonia (NH3), hydrogen sulfide (H2S), methyl siloxanes (MSs), nitrogen (N2), oxygen (O2), halogenated volatile organic compounds (VOCs), carbon monoxide (CO) and hydrocarbons whose presence largely depends on the source of biogas. The value of biogas is enhanced further by the production of organic manure as substitutes for chemical fertilizers in crop production. The vast range of applications makes biogas an attractive sustainable energy choice. Bioenergy generation capacity, mainly from biogas globally, has shown promising worth over non-renewable energy options; hence, its production has expanded rapidly during the previous two decades, from 42.38 Exajoules/year in 2000 to about 57.74 Exajoules/year in 2023, an increase of about 36.24%. This study presents the biogas production and potential improvement measures that include factors influencing the process and quality of biogas produces such as C/N (carbon nitrogen ratio, the pH, dilution of feedstock, composition and nutritive value of feedstock, residence period, mixing and stirring, temperature, presence of toxicants, loading time and redox conditions). The main barriers to biogas production and use include lack of technical know-how, lack of subsidies and incentives for biogas production and use. Access to appropriate and affordable biogas technologies, the development of a comprehensive policy on the construction and operation of bio-digesters as well as utilization of biogas and sales of biogas energy products and services are important for an increasing adoption of biogas.”

     The company DESOTEC offers mobile filtration as a way to process raw biogas so that it can be used in some machinery. Their units “remove contaminants, such as siloxanes, which are abrasive, and hydrogen sulfide (H₂S), which causes corrosion and the acidification of engine oil.”

     Upgrading raw biogas to biomethane requires removal of VOCs, siloxanes, terpenes, H₂S, and Ammonia (NH₃). Biomethane is processed to the point where it is 99% methane and can be accepted by gas pipeline grid systems. According to DESOTEC:

“Various technologies are available to separate CH₄ from CO₂ and other molecules in the gas stream. Membranes are one of these technologies, but require protection from siloxanes and other components. DESOTEC’s mobile activated carbon filtration is an effective pretreatment.”

“Scrubbers and bioscrubbers can also be used to remove CO₂, but are less effective at treating H₂S and volatile organic compounds (VOCs). When placed after these technologies as a polishing step, DESOTEC’s sustainable mobile filtration solution ensures that the final product is pure.”

     Siloxane removal is one of the biggest challenges for biogas, particularly landfill biogas. Siloxanes are “chemical structures containing silicon and oxygen bonds and are found in various products like cosmetics and cleaning agents.” They can damage equipment even in small amounts. New research published in the journal Environmental Progress & Sustainable Energy shows that low-cost adsorbents composed of clinoptilolite (a naturally occurring mineral) and biochar (a type of charcoal) can cost-effectively remove siloxane gases from the biogas stream. Some tables, graphs, and the paper’s conclusions and recommendations are shown below.

 

 

References:

 

Biogas. Wikipedia. Biogas - Wikipedia

Six Reasons Anaerobic Digesters Aren’t as Environmentally Friendly as You Think. Power Knot. March 1, 2021. Six Reasons Anaerobic Digesters Aren't as Environmentally Friendly as You Think - Power Knot

Scientists identify low-cost adsorbents for removing impurities from landfill gas. Science X staff. January 6, 2025. Scientists identify low-cost adsorbents for removing impurities from landfill gas

Experimental, economic, and life cycle carbon footprint assessment of low‐cost adsorbents for siloxane removal from landfill gas. Rarosue J. Amaraibi et al. Environmental Progress & Sustainable Energy (2024). Experimental, economic, and life cycle carbon footprint assessment of low‐cost adsorbents for siloxane removal from landfill gas

Air Quality Permitting For Anaerobic Digesters, Part 1. John Hinckley. BioCycle. September 2017. Air Quality Permitting For Anaerobic Digesters | BioCycle

Biogas Production and Process Control Improvements. Moses Jeremiah Barasa Kabeyi, Oludolapo Akanni Olanrewaju and Joseph Akpan. From Biomass to Biobased Products. Edited by Eduardo Jacob-Lopes, Leila Queiroz Zepka and Rosangela Rodrigues Dias. January 12, 2024. Biogas Production and Process Control Improvements | IntechOpen

Biogas and Renewable Energy. Desotec. Biogas and Renewable Energy | Desotec

Income Disparity in the U.S: A Simple Analysis

     I was curious how graphs of income disparity in the U.S. would look so I gathered some data and made some simple graphs. Data comes from AFL-CIO, DQYDJ, the IRS, and others. I made some educated guesses as well. It should be pointed out that salary is only a part of income, especially for executives and CEOs who get much more from other perks like stock, stock options, and much more.

     As can be easily seen the graph is a pretty steady incline from slavery/poverty to the average U.S. salary. This is all before taxes. The average cost of rent in the U.S. is $1372/month, or 16,464/year. This is 66% of the low minimum wage of $25000/year (before taxes) and 53% of the high minimum wage of $31000/year (before taxes).

     The graphs speak for themselves. I added in the 2025 social security limit, above which there is no social security tax. It is now up to $176,000. Any income above that is not taxed, which effectively is a 6.2% tax break for that income which offsets higher rates from entering higher tax brackets. The 2025 rates are shown below.

 

Thus, when we subtract the SS tax from total taxation, 24% becomes 17.8%, 32% becomes 25.8%, 35% becomes 28.8%, and 37% becomes 30.8%. Those are the real, or effective, tax rates. Thus, the highest tax rate for those CEOs and billionaires is 30.8% while the highest rate for those making more than $48475 is 22%, hardly a difference.

     The average CEO salary ($17.7million) is 239 times the average U.S. salary ($74,000- oh what I would give to make that much). The average CEO does not pay social security tax on 98.3% of their income since that is how much of their income is above the limit. 

     Just look at the simple data and you can see that income disparity is something we will have to address eventually. It is inherently unfair. We have billionaires now who are halfway to becoming trillionaires, a word that should only exist in the imagination, not in reality. These are simple graphs of simple data. Graphical evidence is useful to show situations such as this that are perhaps harder to get our brains around because, frankly, they are so absurdly unfair. If you know what it’s like to be poor, to be lower on Maslow’s hierarchy of needs, then you know that life can be unfair. It’s not just life that is unfair but the treatment (by the government, by our business leaders, in some ways by our economic system) of people’s means to get by is also obviously unfair. One of my MAGA friends posted a reminder meme today that ‘Taxation is Theft.’ Perhaps it seems that way if you’re poor but not if you’re rich. Tax is such a small problem for the rich, it can easily be covered by them, yet many of them don’t even file, but choose to cheat. The IRS caught some with new funding efforts toward the problem, recovering billions for the government  but Congress has chosen to claw back much of that funding. Incidentally, the idea that taxation is theft is supported by several different political philosophies. According to Wikipedia:

“The position is often held by anarcho-capitalists, objectivists, most minarchists, right-wing libertarians, and voluntaryists, as well as left-anarchists, libertarian socialists and some anarcho-communists.”

 

Ukraine Offers to Upgrade Coal Units That Currently Run on Anthracite Coal in Moldova Breakaway Region Transnistria to Accept Ukrainian Coal: Ukraine Offers a Deal

     With the recent cutoff of Russian natural gas supplies to some countries in Eastern Europe, there is a need to find other sources of gas as well as other sources of energy. The country of Moldova has secured gas supplies from Europe but has little to spare for the breakaway region of Transnistria, which received gas from Russia before the cutoff.

     Ukrainian president Volodymir Zelensky recently met with Moldovan president Maia Sandu and announced an offer to supply a Transnistrian power plant with Ukrainian coal at a joint press conference. The plant currently burns about 200MW of anthracite coal. The offer is for Ukrainian experts to convert the plant to burn bituminous coal and up the amount burned closer to 2000MW with Ukraine supplying the coal for free in return for receiving some of the electricity from the reconfigured plant. While this is perhaps potential good news for Transnistria and Ukraine in terms of electricity security, the lower-grade coal does mean that air pollution would increase. Specifically, sulfur dioxide pollution would increase. According to The New Voice of Ukraine:

"This is 10 times more than the current level. We are ready to supply coal at a low price or even for free in exchange for electricity for Ukraine and Moldova. This is fair: we supply coal, they have electricity for themselves and all of Moldova, and we get the electricity imports we need," Zelenskyy said, expressing concern about possible Russian interference to use gas as leverage to influence the situation in the region.

"Ukraine is ready to help, and we are very grateful for this gesture. But now everything depends on the regime in Tiraspol. It is important that the assistance offered reaches the people as soon as possible," she said in Kyiv during the official visit on the day of Zelenskyy's birthday.

     Transnistria’s leader Vadim Krasnoselsky was somewhat skeptical of the offer, calling it speculative, according to The New Voice of Ukraine:

"These are speculative suggestions that they will provide coal and so on. I’ll emphasise once again that our plant is technologically fuelled by anthracite. Ukraine offers coal that is not suitable for our plant. We have two coal blocks. They run on anthracite," Krasnoselsky said.

Although the Transnistrian leader noted that the technical conversion of one of the power units to Ukrainian coal is possible, he noted that under "normal conditions", which do not exist, the process would take "more than a year and cost more than 50 million euros".

Anthracite burns much cleaner than bituminous coal but is also much more expensive. It has a very high ignition temperature, burns hotter, and produces less pollutants, but requires more plant maintenance. It appears it would be easier to convert an anthracite plant to burn lower quality coal than to convert from burning lower quality coal to burning anthracite. Anthracite coal also produces more ash than other types of coal, so that would be an advantage to the offer of conversion. As recently as a few years ago around 130,000 homes in the U.S. were burning anthracite coal for heating. I spent a lot of time in Pennsylvania in the 2000s and 2010s and I remember bags of anthracite coal being commonly for sale. Anthracite is produced in Eastern Pennsylvania so its local-ness makes it less expensive there.

     Moldova also recently agreed to provide 3 million cubic meters (about 105 MMCF) of natural gas to Transnistria. According to the Moscow Times:

“The move follows the European Commission’s pledge of an emergency assistance package worth 30 million euros ($31.5 million) to Moldova. The funds are intended to help restore electricity and heating in Transnistria over the next two weeks.”

This is an emergency loan for gas and will not last very long. Transnistria has had to shut down industrial operations that use natural gas until sufficient gas supply can be secured. Moldova is also prepared to assist Transnistria in accessing natural gas on the European market.

     Zelensky also offered to transport natural gas from Azerbaijan to Europe, although those supplies may be limited. Several Eastern European countries including Hungary and Slovakia have also been affected by the gas cutoff. Hungary’s president Orban is threatening to block aid to Ukraine until Russian gas is restarted and has tried but that is unlikely to happen.

 

References:

 

Ukraine offers gas transit from Azerbaijan, sparking doubts. LOS. Essa News. January 25, 2025. Ukraine offers gas transit from Azerbaijan, sparking doubts

Kyiv offers energy lifeline and expertise to Moldova amid crisis. The New Voice of Ukraine. January 27, 2025. Ukraine, Moldova push for energy cooperation amid Transnistria crisis / The New Voice of Ukraine

Transnistria considers coal supplies from Ukraine in exchange for energy "speculative". Artur Kryzhnyi. Ukrainska Pravda. January 27, 2025. Transnistria considers coal supplies from Ukraine in exchange for energy "speculative"

Moldova Approves 3M Cubic Meter Gas ‘Loan’ to Transnistria. The Moscow Times. January 27, 2025. Moldova Approves 3M Cubic Meter Gas ‘Loan’ to Transnistria

Disadvantages Of Anthracite Coal And Common Problems – Is it Worth Buying? House, Home, and Garden. 2022. Disadvantages Of Anthracite Coal And Common Problems – Is it Worth Buying? - The Ultimate Home Living Blog

On-Site Landfill Leachate Treatment Plants for Common Landfill Contaminants, PFAS, and Other Contaminants of Emerging Concern (CECs)

     In 2015 the U.S. Geological Survey’s Environmental Health Program conducted nationwide research on the contamination found in landfill leachate. The study focused on contaminants of emerging concern (CECs) found in leachate that was disposed of off-site, after on-site treatment. The study analyzed leachate from 22 landfills for 190 CECs. The study utilized both municipal and private landfills, geographically distributed, and of different ages in order to get a more comprehensive survey. The CECs include pharmaceuticals, industrial chemicals, household chemicals, steroid hormones, and plant/animal sterols. Below is what they found.

“Scientists determined that final leachate samples contained 101 of the 190 chemicals analyzed for the study, with chemicals present in every final leachate sample collected at levels ranging from as low as 2 nanograms per liter (ng/L) to as high as 17,200,000 ng/L. The most frequently detected CECs were lidocaine (local anesthetic, found in 91 percent of samples), cotinine (nicotine breakdown product, 86 percent), carisoprodol (muscle relaxant, 82 percent), bisphenol A (component for plastics and thermal paper, 77 percent), carbamazepine (anticonvulsant, 77 percent), and N,N-diethyltoluamide (DEET, insect repellent, 68 percent).”

The levels of CECs were much lower in final leachate compared to those observed in fresh leachate samples from previous studies, as would be expected. The final leachate has a path to the environment. Once there it would be even more diluted, but still present and accumulating.

“The results of the present study provide useful precedents for future investigations of the fate, risk, and toxicity of CECs in landfill leachate as they directly or indirectly enter aquatic and terrestrial environments. Such research provides information that can be used to support decisions about the regulation of unwanted/unused pharmaceuticals and leachate treatment methods; better understanding of the fate of CECs in leachate in landfill systems; and better understanding of the ecological effects posed by disposal of leachate to potential environmental receptors.”

 

Landfill Leachate Treatment and Management

     A 2022 paper in Materials Today reviewed landfill leachate treatment methods. From the abstract:

“Landfill leachate is characterized by very high chemical oxygen demand (COD) and biochemical oxygen demand (BOD) consisting of unappealing constituents like toxic organic and inorganic pollutants. In general, leachate parameters such as landfill age, COD/BOD ratio, and COD are the decisive factors in the selection of appropriate treatment methods. The various adopted technologies for leachate treatment are assessed and summarized under heads like biological, physicochemical, and hybrid methods.”

They noted that combination treatment utilizing both biological and physicochemical treatment had the best outcomes for meeting water quality standards. They were best at achieving the most efficient satisfactory removal of COD, BOD, and ammonia nitrogen.

     A 2021 paper in Water Reuse explored the different methods of landfill leachate treatment and their efficacies. From the abstract:

“Different treatments comprising biological methods (e.g. bioreactors, bioremediation and phytoremediation) and physicochemical approaches (e.g. advanced oxidation processes, adsorption, coagulation/flocculation and membrane filtration) were investigated in this study. Membrane bioreactors and integrated biological techniques, including integrated anaerobic ammonium oxidation and nitrification/denitrification processes, have demonstrated high performance in ammonia and nitrogen elimination, with a removal effectiveness of more than 90%. Moreover, improved elimination efficiency for suspended solids and turbidity has been achieved by coagulation/flocculation techniques. In addition, improved elimination of metals can be attained by combining different treatment techniques, with a removal effectiveness of 40–100%. Furthermore, combined treatment techniques for treating landfill leachate, owing to its high chemical oxygen demand and concentrations of ammonia and low biodegradability, have been reported with good performance. However, further study is necessary to enhance treatment methods to achieve maximum removal efficiency.”

Below is a table of leachate characteristics and treatability based on landfill age. There are significant differences. Some contaminants are volatile and escape, in some cases causing local air quality concerns. Below the table are flow charts showing the most reported landfill leachate treatment methods.  

     An October 2024 paper in Desalinization and Water Treatment explored the challenges, methods, and future directions of landfill leachate management. They note that better solid waste management, more functional circular economies, and higher levels of recycling would reduce the amount of waste landfilled and the amount of leachate generated. They also mention the benefits of gas recovery and gasification/pyrolysis for waste-to-energy applications in reducing leachate volumes. The paper’s authors note some of the newer treatment methods showing success:

“Advanced treatment technologies, including integrated advanced oxidation processes (AOPs) with biological processes and adsorbent-enhanced constructed wetlands, demonstrated promising cost-effectiveness and high treatment efficiency, with savings of up to 32 % in treatment costs. Future research should focus on emerging technologies like nanotechnology and artificial intelligence for process optimization, and the impact of municipal leachate on air quality. Continued innovation in leachate treatment and sustainable practices are essential for effective waste management.”

Since leachate is a contamination source with a highly variable composition, the treatment methods vary. There are many different treatment methods that can be used.  The authors of this paper explored the methods shown below along with some models of leachate fate and transport in the environment and charts of waste types and landfill types based on waste. They also explored several different combinations of methods.

     Company USP Technologies describes some of the strategies and challenges of landfill leachate treatment below:

“Landfill leachate can be very challenging to effectively treat as it is often characterized by significant odor, high COD, phenols and dissolved metals. In some cases, leachates can be toxic or inhibitory to downstream biological treatment systems. Furthermore, due to the variability of landfill material, weather patterns and content age, leachate constituent levels can change over time, adding to the complex nature of treatment. Landfill operators contend with additional challenges stemming from general public odor complaints, discharge compliance and fines or surcharges from municipal wastewater treatment plants.”

 

Trends in PFAS Management from Leachate

     The so-called “forever chemicals” that include PFAS are being addressed due to public concerns. In 2023, there were some pilot projects for on-site treatment of PFAS in leachate. Casella Waste Systems began treating for PFAS at the Coventry Landfill in Vermont. Vermont has been adopting limits on perfluoroalkyl and polyfluoroalkyl substances, including PFAS, PFOS, and PFOA. Federal limits for PFAS in drinking water were adopted by the EPA in April 2024. The EPA’s final rule sets the following limits

·        Enforceable maximum contaminant levels of 4 parts per trillion for PFOA and PFOS.

·        Non-enforceable maximum contaminant level goal of 0 ppt for PFOA and PFOS, reflecting that “there is no level of exposure to these contaminants without risk of health impacts, including certain cancers.”

·        Enforceable MCL, and a MCL goal, of 10 ppt for PFNA, PFHxS and HFPO-DA, the last of which are also known as “GenX Chemicals.”

·        Additional limits for “any mixture of two or more of” PFNA, PFHxS, PFBS and GenX Chemicals

The 4ppt for PFOA and PFOS is a very small amount that was unmeasurable with older technology. The low limit suggests the very real dangers of these chemicals. According to Waste Dive:

“The rule states that public water systems must complete initial monitoring for the chemicals within three years and inform the public of those results. If PFAS is found at levels that exceed the standards then operators must implement solutions within five years. The agency estimates this will affect 6% to 10% of the United States’ 66,000 public drinking water systems.”

At the same time, the EPA announced $1 billion in grants to test for these chemicals as part of the $9 billion set aside for addressing PFAS in the IRA. Waste Dive also notes that even before these limits were set there were instances of wastewater treatment facilities not accepting treated leachate due to PFAS concerns. Thus, PFAS pre-treatment is becoming more common as well as more demanded.

     In New York, several environmental groups have urged the state DEC to require onsite leachate treatment at landfills that can reduce PFAS instead of shipping it to wastewater treatment plants ill-equipped to handle these chemicals. They are also calling for the DEC to write PFAS limits into wastewater treatment plant water permits. New state legislation, although delayed in 2024, is expected in 2025. The groups also noted their own studies that have shown that these chemicals have been commonly found to exceed limits for drinking water:

“PFAS contamination is a core concern of the groups. They cite a DEC study that found that groundwater PFOA and PFOS concentrations exceeded the state’s drinking water standard at 68% of the state’s closed landfills tested to date. Within the report’s project area, at least eight closed landfills showed groundwater PFAS concentrations above the drinking water standard.”

     Upgrading landfills to treat leachate onsite for CECs, including PFAS and related chemicals, will take time and money, unfortunately. Also uncertain is how the Trump administration presumably under Lee Zeldin, who is expected to be confirmed, will treat the issue as deregulation is emphasized and regulation is de-emphasized.

 

References:

 

Groups urge New York DEC to require on-site landfill leachate treatment. Jacob Wallace. Waste Dive. January 23, 2025. Groups urge New York DEC to require on-site landfill leachate treatment | Waste Dive

EPA sets drinking water standards for PFAS, kicking off questions for waste operators. Coel Rosengren. Waste Dive. April 20, 2024. EPA sets drinking water standards for PFAS, kicking off questions for waste operators | Waste Dive

Some landfills will begin treating PFAS on-site as regulators move to adopt new limits, April Reese. Waste Dive. January 17, 2023. Some landfills will begin treating PFAS on-site as regulators move to adopt new limits | Waste Dive

Landfill Leachate Released to Wastewater Treatment Plants and other Environmental Pathways Contains a Mixture of Contaminants including Pharmaceuticals. U.S. Geological Survey. Environmental Health Program, November 13, 2015. Landfill Leachate Released to Wastewater Treatment Plants and other Environmental Pathways Contains a Mixture of Contaminants including Pharmaceuticals | U.S. Geological Survey

Treatment of landfill leachate with different techniques: an overview. Amin Mojiri; John L. Zhou; Harsha Ratnaweera; Akiyoshi Ohashi; Noriatsu Ozaki; Tomonori Kindaichi; Hiroshi Asakura. Water Reuse (2021) 11 (1): 66–96. Treatment of landfill leachate with different techniques: an overview | Journal of Water Reuse and Desalination | IWA Publishing

Landfill Leachate – Liquid Phase Treatment. USP Technologies. LANDFILL LEACHATE – LIQUID PHASE TREATMENT - USP Technologies

Sustainable municipal landfill leachate management: Current practices, challenges, and future directions. Chinenye Adaobi Igwegbe, Eduardo Alberto López-Maldonado, Andrea C. Landázuri, Prosper Eguono Ovuoraye, Annex Ifeanyi Ogbu, Nicolás Vela-García, and Andrzej Białowiec. Desalination and Water Treatment. Volume 320, October 2024, 100709. Sustainable municipal landfill leachate management: Current practices, challenges, and future directions - ScienceDirect

A short review on landfill leachate treatment technologies. Aishi Nath and Animesh Debnath. Materials Today: Proceedings. Volume 67, Part 8, 2022, Pages 1290-1297. A short review on landfill leachate treatment technologies - ScienceDirect