In a letter to Congress, SWANA and NWRA associations request that regulation under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) for addressing per- and polyfluoroalkyl substances (PFAS) contamination assign environmental cleanup liability to the industries that created the pollution in the first place. Both associations note that MSW landfills and solid waste management, an essential public service do not manufacture nor use PFAS. The industry, and ultimately the general public should therefore not be burdened with CERCLA liability and costs associated with mitigating PFAS from water and wastewater.
May 10, 2022
Re: Relief for Municipal Solid Waste Landfills from CERCLA Liability for PFAS
Dear Chairman Carper, Ranking Member Capito, Chairman DeFazio, Ranking Member Graves, Chairman Pallone, and Ranking Member McMorris Rodgers:
The municipal solid waste (MSW) management sector strongly supports the goal of addressing per- and polyfluoroalkyl substances (PFAS) contamination and holding accountable manufacturers and heavy users of these compounds. We are concerned, however, that regulation under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) instead would assign environmental cleanup liability to essential public services and their customers. We therefore request that Congress provide MSW landfills and other passive receivers with a narrow exemption from liability if certain PFAS are designated as hazardous substances under CERCLA. Doing so would keep CERCLA liability on the industries that created the pollution in the first place.
Context
• Landfills neither manufacture nor use PFAS; instead, they receive discarded materials containing PFAS that are ubiquitous in residential and commercial waste streams. MSW landfills and the communities they serve should not be held financially liable under CERCLA for PFAS contamination, as landfills are part of the long-term solution to managing these compounds.
• Landfills are essential public services that are subject to extensive federal, state, and local environmental, health, and safety requirements. Further, MSW landfills are important to managing and limiting PFAS in the environment, as recognized by the Environmental Protection Agency (EPA) in its December 2020 draft Interim Guidance on the Destruction and Disposal of [PFAS] and Materials Containing [PFAS].
• Just as certain airports are required by law to use firefighting foam containing PFAS, permitting authorities often require landfills to accept waste streams containing PFAS.
• Most landfills rely on wastewater treatment facilities for leachate management. Wastewater and drinking water facilities increasingly rely on landfills for biosolids management and disposal of PFAS-laden filters. Efforts to address PFAS at MSW landfills and drinking water and wastewater facilities must avoid disrupting this interdependence among essential public services to communities.
• Landfill leachate typically represents a minor proportion of the total quantity of PFAS received at wastewater treatment facilities from all sources. PFAS manufacturers or users, by comparison, contribute PFAS at levels that can be orders of magnitude higher than landfills.
Significant Economic Impacts
• Removing PFAS from landfill leachate requires advanced treatment techniques which are prohibitively expensive. Estimated capital costs to implement leachate pretreatment at a moderate-sized landfill to the extent necessary to significantly reduce PFAS range from $2 million to $7 million, with nationwide costs totaling $966 million to $6.279 billion per year for the solid waste sector. Trace concentrations of PFAS nevertheless would remain in leachate following pretreatment, exposing landfills to CERCLA liability.
• Absent relief from CERCLA liability, manufacturers and heavy users of PFAS compounds will bring claims for contribution against landfills and other passive receivers, generating significant litigation costs. EPA’s exercise of enforcement discretion will not insulate landfills from this litigation.
• These costs will be passed along to communities, water and wastewater treatment facilities, and biosolids management, all of which rely on the services of MSW landfills.
Broad Unintended Consequences
• CERCLA regulation will impel landfills to restrict inbound wastes and/or increase disposal costs for media with elevated levels of PFAS, including filters, biosolids, and impacted soils at Department of Defense facilities. The mere prospect of regulation in this area is already disrupting the interdependence of the drinking water, wastewater, and solid waste sectors.
• Food waste compost may contain PFAS due to contact with PFAS-lined packaging materials. As a result, a CERCLA designation could result in communities diverting food waste from organics recycling programs, hindering federal, state, and local climate and waste reduction goals.
• Cost increases likely will have a significant disproportionate impact on low-income households that rely on the affordability of services that the solid waste sector provides.
Recommendation
Although our sector is simultaneously pursuing “no action assurance” from EPA, the agency historically has been very hesitant to provide this relief given its policy that assurances should be given only “in extremely unusual cases.” As such, and acknowledging that EPA may have limited authority to act on our request, we recommend providing the following narrow exemption from CERCLA liability that affords relief to landfills and other passive receivers of PFAS1:
(a) IN GENERAL.—No publicly owned or operated community water system (as defined at 42 U.S.C. 300f), publicly owned treatment works (as defined at 33 U.S.C. 1292), or municipal solid waste landfill (as defined at 40 C.F.R. 258.2) shall be liable under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (42 U.S.C. 9601 et seq.) for the costs of responding to, or damages resulting from, a release to the environment of a perfluoroalkyl or polyfluoroalkyl substance designated as a hazardous substance under section 102(a) of such Act that resulted from the discharge of effluent, the disposal or management of biosolids, the disposal of filtration media resin, or the discharge of leachate where such actions are in compliance with Federal or State law and all applicable permits.
(b) EXCEPTION.—Subsection (a) shall not apply with respect to any discharge described in such subsection that results from any gross negligence, willful misconduct, or noncompliance with any Federal or State law or permit governing the discharge of effluent, disposal or management of biosolids, disposal of filtration media resin, or waste disposal.
Thank you for your consideration of our request, and we look forward to continuing to partner with the federal government to ensure the safe and effective management of waste streams containing PFAS.
Sincerely,
National Waste & Recycling Association
Solid Waste Association of North America
cc: Senate EPW Committee Members
House T&I and E&C Committee Members
_______________________________________
1 The exemption would not extend to underlying soil and groundwater contamination from a MSW landfill or to facilities other than MSW landfills that accept waste streams with elevated concentrations of PFAS.
EPA Requires Reporting on Releases and Other Waste Management of Certain PFAS, Including PFBS
As part of EPA’s Strategic Roadmap, the Agency announced the automatic addition of four per- and polyfluoroalkyl substances (PFAS) to the Toxics Release Inventory (TRI) list.
As of January 1, 2022, facilities that are subject to reporting requirements for these chemicals should start tracking their activities involving these PFAS as required by Section 313 of the Emergency Planning and Community Right-to-Know Act. Reporting forms for these PFAS will be due to EPA by July 1, 2023, for the calendar year 2022 data.
In April 2021:
EPA previously updated the Code of Federal Regulations with PFAS that were added to the TRI on January 1, 2021, under section 7321(c) of the NDAA and regulated by an existing significant new use rule (SNUR) under the Toxic Substances Control Act (see 40 CFR 721.10536).
In addition to continuing to add PFAS to the TRI, the EPA will soon announce a series of PFAS test orders requiring PFAS manufacturers to provide the Agency with toxicity data and information on PFAS.
If you have questions or concerns about reporting requirements, contact one of our environmental chemistry – hazardous materials/waste professionals at .
Anna Cerf conducted research at the Environmental Research and Education Foundation, had an internship at the Environmental Defense Fund, and worked for SCS Engineers. Now she’s off to Germany.
Cerf graduated from UVA in 2020 with a degree in civil engineering and a minor in urban and environmental planning. The course work for her program will cover three fundamental disciplines: sanitary engineering, groundwater remediation, and hydraulic engineering.
She is a Rotary Global Grant Scholar, using an award to fund her two-year master’s program in water resource engineering and management at the University of Stuttgart. “With the support of ISWA professors and access to University of Stuttgart’s premier research facilities, I will research the transport and treatment of emerging contaminants for my master’s thesis.”
Cerf feels having a master’s in water resource engineering and management will further her career at the intersection of environmental issues and public health. “The University of Stuttgart has top-of-the-line water research facilities,” Cerf said. “It is also home to the Institute of Sanitary Engineering, Water Quality, and Solid Waste Management.
“By the end of the program, I will be able to anticipate, understand and evaluate water management-related issues,” Cerf said. “As climate change exacerbates existing water scarcity issues and environmental degradation damages water quality, these skills become increasingly important.”
Read more about this accomplished SCS Young Professional.
The findings of the studies reviewed in this report are encouraging concerning the ability of today’s U.S. WTE facilities to effectively treat solid waste that contains PFAS and not emit detectable levels of PFOA in the process. For the formation of PICs, the pilot-scale investigation conducted at the Karlsruhe Institute of Technology is encouraging in its findings that the combustion of PTFE did not create any of the 31 types of PFAS suspected of being potential PICs produced during the combustion process.
In conclusion, based on this research, SWANA is cautiously optimistic regarding the role of WTE facilities in the destruction of PFAS in MSW. The thermal destruction of PFAS in high-temperature combustion systems such as WTE facilities may represent one of the few commercially proven options available to society to destroy these problematic, forever chemicals.
The full report, PFAS Fate and Transport in Waste-to-Energy Facilities, is currently only available to SWANA ARF subscribers. SWANA members receive free access to ARF industry reports one year after publication; the abstract is available online and worth reading.
Landfill operators forever work to stay on top of a diverse and complex mix of leachate contaminants—heavy metals, ammonia, and biochemical oxygen demand (BOD), among them; but lately, they think about even more. For one: how to keep concentrations of these contaminants within wastewater treatment’ plant’s tightening discharge limits. Add to this concern the possibility of more compliance pressure as the constituents’ list on regulators’ radar grows. From microplastics to PFAS and PFOA, the latter sometimes called the “elephant in the room” –some operators are preparing for what may be down the pike.
Among strategies, some are looking at are on-site leachate treatment options, and there are several. Finding the most fitting, sustainable, and cost-effective one takes vetting. This continuing blog series explores studies conducted by SCS Engineers for operators nationwide. Here you will get an inside look at what these leachate management experts found, what treatment system they recommend in each scenario, and why.
A Solution to a Nebraska Landfill’s Rising Leachate Volumes
A Nebraska landfill needs to manage its rising volumes of leachate, causing disruptions to operations. The liquid goes into a 20,000-gallon tank, is pumped into a tanker, and is driven to the municipal wastewater treatment plant. The tank was filling so fast that the operator has trouble staffing and scheduling its few commercial driver’s-licensed operators to haul it. This logistical task has become a near-daily necessity. Sometimes the liquid level indicator will go off on the weekend. Management has to move quickly, sometimes on a dime, find someone to come in, and pay overtime.
“The staffing challenge is the main issue that brought the operators to SCS. They want to understand the whole leachate management structure better, and as we answer their questions, they want to know how we can improve the overall system in the long-term, says Zach Mahon, the SCS staff professional who works on the project. “After an extensive assessment, we provide options whereby the operator no longer has to pump leachate to a holding tank and then truck it to the wastewater treatment plant. And we provide site-specific recommendations to take their leachate management practices further,” he says.
Mahon and the SCS team of leachate management experts headed to the landfill to talk to operations staff and get their historical generation records, which is the basis they start with for their assessment. “We correlate the landfill information with our research to determine yearly generation figures as well as a peak generation number over the landfill’s projected life. This site is expanding, and we want to size the equipment so that when it reaches capacity, the system can handle the higher volume,” Mahon says.
SCS plans in other ways to ensure the recommended technology will take its client into the future on solid footing. For instance, accounting for the reality that operators may one day have to remove per- and poly-fluoroalkyl substances (PFAS) to send their multi-thousands of gallons of leachate to their wastewater treatment plant each year. Operators are keenly aware that utilities and regulators are looking with more scrutiny at PFAS and other emerging contaminants of concern.
Through due diligence, SCS engineers came up with three treatment options. Mahon explains each:
Install a leachate force main. This system includes a pipe with a pump that pushes the liquid through the force main, directly to the sewer line and, ultimately, to the municipal treatment plant. The pump kicks in automatically, negating the need to have drivers in the wings at all times. This system is quick to build and fairly simple to operate. It is the least expensive of the modifications that SCS vetted.
Install a leachate evaporator, which heats the liquids and evaporates the water molecules. This system reduces leachate volume by 90%. Managing liquids on-site eliminates dependency on drivers, but on the wastewater treatment plant too. The gas-fueled system is suited for sites with surplus landfill gas to help cut their operational costs.
Install a reverse osmosis treatment (RO) system where material passes through a membrane, which separates contaminants. RO treatment can reduce contaminated water by 90%, typically rendering it clean enough to discharge directly to surface water with appropriate permits. Or, it can be discharged to the city sewer, eliminating the permitting step.
“For each leachate treatment option, we looked at cost, the feasibility of short- and long-term implementation, and regulatory acceptance,” Mahon says. “We deliver the data with these priorities in mind, make our recommendations, and leave it to our client to decide.”
What did the SCS team recommend in this scenario?
“We suggested the force main. It solves the primary operational issue around staffing. And the economics of this comparatively inexpensive system make sense in these times when landfills are dealing with astronomical leachate management costs, among other increasing operating and capital expenses,” he says. This option does more than meet the client’s most immediate needs at a minimal cost. It provides the option to upgrade should regulators’ requirements around leachate change or should the wastewater treatment plant tighten its discharge limits. We design the modular system to add on reverse osmosis if necessary in the future. Thus, we help ensure that our client will continue having a home for its leachate.
A value-add, regardless of the operators’ decision, is more knowledge. SCS clients have a deeper understanding of industry standards. They are also more aware of how the industry is shifting in managing leachate and how these shifts could affect them. We follow up with technical bulletins explaining proposed and final federal rules in plain language influencing their operations, deadlines, and how to provide feedback to the appropriate agencies.
“We provide a lot of data to continuously inform our clients and to help them compare their operational costs now to what they would be if they invest in a new leachate management strategy. We ensure they fully understand each option’s capabilities to decide if it pencils out for their budget and operations. They have what they need to make informed decisions for a hands-off system to take them into the future,” Mahon says.
Leachate and Liquids Management
Managing oil and gas waste is challenging, even when practicing due diligence. The job requires impeccable skill and attention and sometimes outside support, which Colorado operators recently learned when they found high oil content in leachate coming out of their sump. They turned to SCS, knowing through their longstanding relationship with the engineers and that their liquids management team could deal with oil-laden wastewater.
Ensuring sustainable outcomes begins with collecting and analyzing comprehensive data that become the building blocks for a feasibility study. The study helps with immediate challenges and builds a more holistic approach to tackle increasingly expensive operation challenges at landfills.
“First, we talk about the site’s leachate history, including quality and quantity. What is the source of the waste generating the leachate, and where is it deposited? How are liquids used in current operations? The current practice used the liquids on the landfill surface for dust control, leaving an unsightly oily sheen.
Once we talk about how the site currently manages these liquids, we discuss options for future handling for improvement,” says Neil Nowak, SCS Engineers project director. “You’ve got to have a holistic understanding of day-to-day operations with the data to solve the problem cost-effectively.”
Neil’s preliminary research led to one recommendation to meet all the criteria – separate oil and water from leachate as the liquid exits the pump. The separation process can reduce the oil-laden leachate volume by 70 percent.
The technology works by separating the leachate into oil and water portions using an oil/water separator, such as a gun barrel tank, which is low cost and effective. After piping the water to an evaporation pond, the collected oil is sent offsite for future handling, usually disposal.
“This method gives the operator a better option for dealing with the leachate over the current practice of spraying it on the landfill surface for dust control,” Nowak says.
Spraying usually provides an alternative for liquids while reducing disposal time and cost. However, he explains, oil-laden leachate is a different beast than typical MSW liquids and calls for a more creative solution to remain within regulatory compliance.
Oil and water separation eliminates the aesthetics issues at the site with its previous practice. The greater value is that this method gives operators full control of oil’s movement, which can otherwise be very hard to accomplish.
“Oily leachate can adhere to the wheels of equipment that move dirt over the landfill surface; consequently, it ends up in places operators do not want it to go. Oil and water separation technology is a reliable way to keep it out of surface drainage areas and ensure it does not infiltrate into groundwater outside of the lined space,” Nowak explains.
Operators avoid short- and long-term consequences springing from compliance issues, but beyond today, the technology that SCS sizes operates for 20-plus years and helps prepare them for the long haul.
This option enables waste pros who take on growing demand from the oil and gas industry to protect the environment and public health, even as volumes increase. Oily liquids are particularly challenging for wastewater plants. Separation technology provides greater assurance that the landfill will still have a home for their leachate as wastewater treatment plants raise the bar on what they will allow.
The remaining question…
What is the most cost-effective and safe way to eliminate the filtered oil?
The solution for the immediate need is straightforward and simple. Depending on geology, local regulatory policy, and cost factors, solidification or injection are the most common, safe practices now, but reuse options are under development. Reuse and prevention are part of a longer-term landfill strategy, so Neil draws on his colleagues’ expertise.
Nowak’s expertise comes from years of experience supporting the oil and gas industry. Backing him is national liquid management expert Nathan Hamm, who lends technical expertise and insight on best practices for reducing leachate.
Explains Hamm:
Commonly the best bang for your leachate management dollar is to reduce the volume of leachate or wastewater to treat in the first place. Operators can begin by diverting stormwater away from active portions of the landfill, then installing a better cover system. Depending on the landfill’s need and location, reducing the size of new cells and timing those new cells to come online during low precipitation seasons is practical. Leachate minimization practices such as these directly reduce the treatment system capital and ongoing operational costs.
The Colorado operator now has oil and gas waste management options and has a comprehensive, site-specific review of leachate management with a clear understanding of where there is room for improvement.
As far as their immediate priorities, says Nowak, “We have left them with enough thought-out information to make informed decisions, and for now, they are leaning toward the oil and water separation technology. Though they can keep operating without it, they are looking to get ahead of possible compliance issues by making changes voluntarily, which are usually less costly in the end and demonstrates social responsibility to the Colorado Department of Public Health and Environment and the EPA.
Liquids and Leachate Management
Not too long ago, SCSer Gomathy Radhakrishna Iyer thought she’d become a mechanical engineer but decided to go down another path at her father’s coaxing, and she’s never looked back. Today she is a Civil & Environmental Engineering Ph.D. and has become deeply entrenched in the world of landfills—human-made formations that she calls “beautiful.”
Dr. Iyer’s work spans research and engineering projects in landfill gas emissions reduction, landfill design, and leachate management. She’s also keeping up with PFAS to be ready for what may lie ahead around these emerging contaminants. “What I’m most into these days is researching and helping clients select leachate treatment systems and doing landfill expansion designs. It’s so mentally rewarding when you find solutions for the client’s problems. They are happy, and you are happy,” says the SCS staff professional.
She is known by more than her work family. Gomathy is a published researcher and speaker, most recently presenting at the Global Waste Management Symposium in February 2020. Her presentation covered one of her pet topics, her Ph.D. focus: using grass clippings and biosolids as biocovers to remove methane from landfills.
Pre-COVID, she spent many of her days in the field. Lately, she spends a little more time anchored to her computer in her home office. There she typically works on a few spreadsheets at a time, maybe as part of a gas emissions report, a stability analysis, or settlement analysis. Then she shifts her focus to her design drawings. Dr. Iyer still manages to break away to put on her PPE – her hardhat, safety vest, and steel-toed boots. She happily drives off in a company truck to the landfill, lugging field parameter testing probes and a 10-pound ISCO to collect leachate samples; or do other fieldwork like locating LFG wells and pipes or other features that help her design.
In the summers, it gets scorching hot. And the winters can be bone-chilling cold, especially for a woman who spent most of her life in India, where she was born and raised. In her last years there, she studied the transport of heavy metals through groundwater. Then, it was on to the University of Texas, Arlington, where she earned her Ph.D. and became set on finding work at SCS, coming on board in 2019.
Among her earliest challenges was communication. “Sometimes I would be in a meeting or having lunch with my colleagues, and they would bring up baseball or other games or a Netflix series. They were new concepts to me, and I couldn’t relate. While I speak English, I was unacquainted with the vernacular. I was like, what is Super Bowl? I thought maybe it was something very big that people eat from,” she recalls. That does not stop a researcher.
Finding a way to become better acclimated became a project of sorts. She started spending weekend downtime in front of the TV to learn about these American pastimes. Baseball still isn’t her first love, but she’s happy to say, “In 2019, I went to my first Washington Nationals game with a big group from SCS, and I had at least some knowledge of what was going on.”
The ambitious civil engineer has pushed past another on-the-job challenge—one brought on by the impulse to know every detail she can nail down before setting to work. “Since I’m from a research background, I tend to dig to the very bottom to try and know the problem completely. Sometimes it’s a good thing. But I’ve had to be conscious of time constraints, gain an understanding of the minimum required to do the job well, and move on,” she says.
What first brought her to the United States was her husband, Ramesh Padmanabhan. He was working on a Ph.D. at the University of Texas at Dallas while she was studying in India, so the relationship truly began as a long-distance one. They got to know each other through a combination of old-world traditions and 21st Century channels. “Ours was an arranged marriage. Our parents introduced us, and for the first year, we met up and talked on SKYPE,” Dr. Iyer recollects. He’s a molecular and cell biologist and sometimes her consultant too.
“In my job, I need to know the biology and chemistry of microbes as they are responsible for breaking down waste, and he is my encyclopedia. I don’t have to Google as much when he’s around.” She adds: “I can’t complete my story without talking about my brother who has given me unconditional support and career advising through my life. These two men are pillars of my life.”
As a woman civil engineer who’s all about waste, she’s in the minority, but she doesn’t feel as if she is because women are moving into waste engineering. She’s one of four women on an eight-person team, who she says is “like my family. And my supervisor is a great supporter of women in STEM (science technology, engineering, and math).”
She hears from many newly degreed civil engineers, including “young ladies” with questions about waste management. They read blogs about her work that originated on SCS’s website and are on social media. “These graduates want to take their career to the next level, and they have a lot of questions about how to start solving waste issues,” she says. She tells them that solid waste management is one of the best and most stable industries they can choose and that the pandemic has driven that point home. “We are reminded through COVID that waste management is an essential business, and there will always be jobs to support it,” she says.
What Dr. Iyer loves most about her job is what she and her team imagine and draft in drawings, keeps developing, and in time, is built. “It’s like giving birth to a baby. Very exciting,” she says. Her groundwater contamination remediation work got her interested in PFAS, even before she finished her studies. “I had a lab mate in school who did PFAS research. That got me curious about these emerging contaminants. I’ve stayed vigilant to keep up with what’s happening with regulations and treatment options under research. If regulations now under consideration are implemented, our clients will have to start thinking more proactively about addressing PFAS. So, we need to learn more on a holistic level about what these contaminants can do and the best way to treat them.”
She tells the story of how her venture into civil engineering started with her father. “He wanted to be a civil engineer himself but was the eighth son, so his parents couldn’t afford tuition, and in India, you don’t go to college once you are grown with a family,” she explains. He wanted his daughter, already drawn to engineering, to pursue what had been his dream and said he thought it would suit her better than the direction she was leaning. “Had I studied mechanical engineering as I’d been thinking of doing, I would not have come into waste.” She is happy with where she’s landed.
“When you work all day and still are not tired –you still enjoy it and are happy to contribute to something good—that’s how you know it’s the right fit.”
Lately, landfill operators are putting stock in onsite landfill leachate treatment systems as a strategy to stay on top of increasing requirements in their already demanding regulatory world. Leachate treatment systems help meet tightening restrictions on liquids that landfills send to municipal wastewater treatment plants or discharge directly. And onsite leachate treatment gives operators a leg up should they one day have to deal with any emerging contaminants found on an expanding list.
With their eyes on compliance, landfill owners and operators are looking to leachate treatment systems that can ease the impact of soaring leachate disposal costs. Of course, the more contamination, the harder the hit since higher contaminants can mean higher municipal treatment plant surcharges or the landfill having to haul its leachate longer distances to a treatment plant that will accept it. Both examples usually result in higher treatment, disposal, and hauling costs.
A spike in its ammonia concentrations was enough impetus for one Oregon landfill operator to turn to SCS Engineers a few months ago. At its highest levels, the ammonia climbed to 50-fold what many small wastewater treatment plants, like the one in the Northwest, will take over the long-term.
Project Director Shane Latimer and Technical Lead Sam Cooke got on the stick to figure out how their client could keep hauling and disposing of leachate at the local wastewater treatment plant it has routinely relied on for years.
Coming up with a plan is a complex, multi-step process that requires looking through many lenses. To design a cost-effective, efficient treatment facility, Latimer and Cooke use an in-house multidisciplinary team of co-workers from Project Management, Chemical Engineering, Civil Engineering, and Geotechnical Engineering. The team performs in-depth analyses to identify the most economical and feasible technology. A design that in this case not only addresses ammonia but prepares the operator for emerging contaminants, such as the possible need for per and polyfluoroalkyl substances (PFAS) reduction, which Cooke describes as a train that has not yet arrived in Oregon but has left the station and is heading down the track.
Starting with the most immediate concern, Cooke says, “Our client had seen ammonia concentrations between 500 and 1,500 mg per liter, which is high. Acceptable ammonia levels can vary depending on the type of facility and how much leachate they expect to get compared to their total flow. But small treatment plants like the one our client depends on will set ammonia limits of about 25 or 30 mg per liter,” he says.
SCS begins with a leachate pretreatment options analysis to dive into details beyond ammonia levels – spikes in ammonia call for close attention. Still, there’s more to consider in masterminding a robust and fitting plan to manage the complex process.
“These are biological treatment systems, and there is no one-size-fits-all answer. You need to know how these systems will react to whatever is in your leachate, so you have to account for more than ammonia, or whatever your constituents of concern are,” Latimer says.
SCS’s leachate contaminant analyses use the landfill’s historical data along with what they learn from tests that SCS orders to understand alkalinity, pH, and carbon, among other leachate chemistry puzzle pieces.
“We look at concentrations of raw leachate, flow rate, pretreatment requirements, and other factors. We want to get a comprehensive picture of the problem and ultimately make the best treatment decision to get compound concentrations down to acceptable discharge levels,” Latimer explains.
What customized solution did the team design for the client in Oregon? The system of choice is a membrane bioreactor (MBR), which combines membrane separation technology with traditional activated sludge technology with optional reverse osmosis treatment. The design is a compact, efficient, biological wastewater treatment plant.
“An MBR is an elegant solution. We found it to be a good choice for this application for several reasons. It takes up relatively little space and fits well within the available plant footprint. It produces a relatively low-volume waste sludge stream. And it can cost-effectively treat multiple constituents of concern, so should new leachate chemistry issues arise, an MBR can address many of them,” Cooke says.
Being able to handle multiple concerns if and when they arise is key here. Cooke and Latimer wanted not only to get the immediate problem in check but see that the client has a dynamic and robust system to tackle whatever new challenges may be down the road.
When SCS goes into design mode, they plan ahead by engineering modular systems to add additional treatment methods if and when they’re necessary.
“For instance, MBR treats the leachate to reduce ammonia, other nutrients, organics, and suspended solids. By leveraging this treatment method first, you eliminate a lot of the bulkier constituents. But we left room for a modular addition such as reverse osmosis for “polishing,” treating MBR discharge for other minor constituents including PFAS,” Cooke says.
The client who came to SCS for a relatively inexpensive remedy for an ammonia problem now has a feasible, economical asset for leachate management.
“These investments are good security for landfill operators,” says Latimer. “If a municipal wastewater treatment plant is struggling to meet its standards, eliminating one contributing source of wastewater, like a landfill, could potentially solve several issues, such as ammonia, biochemical oxygen demand, and total suspended solids.”
But these treatment systems provide added security for more than the landfill.
“When disposal sites invest in sound leachate treatment systems, it’s also good for municipal wastewater treatment plants. It assures them that landfill operators will help them with the overall regulatory burden. We are helping them both to prepare for present and future challenges,” says Latimer.
Additional Resources:
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Landfill Leachate for Heavy Industry
SCS’s leachate management team is available to answer your questions on this blog or our other treatment designs at
EPA is releasing the interim guidance for public comment. The guidance provides information on technologies that may be feasible and appropriate for the destruction or disposal of PFAS and PFAS-containing materials. It also identifies needed and ongoing research and development activities related to destruction and disposal technologies, which may inform future guidance.
The interim guidance addresses PFAS and PFAS-containing materials including:
The agency is also providing guidance on testing and monitoring air, effluent, and soil for releases near potential destruction or disposal sites. EPA’s interim guidance captures the significant information gaps associated with PFAS testing and monitoring and identifies specific research needs.
The interim guidance is intended to assemble and consolidate information in a single document that generally describes thermal treatment, landfill, and underground injection technologies that may be effective in the destruction or disposal of PFAS and PFAS-containing materials.
As further research and development occur on this issue, EPA will incorporate this increased knowledge into future versions of this guidance to help decision-makers choose the most appropriate PFAS disposal options for their particular circumstances. EPA will review and revise the interim guidance, as appropriate, or at least once every 3 years.
See the EPA website: EPA Interim Guidance on Destruction and Disposal of PFAS.
Instructions: All submissions received must include Docket ID No EPA-HQ-OLEM-2020-0527 for this rulemaking. Comments received may be posted without change to the Federal eRulemaking Portal. You may send comments by any of the following methods:
According to Waste Dive, the document is the first such federal guidance on the destruction or disposal of PFAS or PFAS-containing materials. It describes the available science used in three major techniques: deep well injection, landfilling and thermal treatment. Acknowledging uncertainty about potential environmental effects, the EPA proposed the interim storage of PFAS-containing waste until further research can “reduce the uncertainties associated with other options.”
Industry groups such as the National Waste & Recycling Association (NWRA) and the Solid Waste Association of North America (SWANA) said they are analyzing the document and discussing with their members, such as SCS Engineers what the interim guidance means for daily landfill operations. The trade groups will submit comments on the document by the Feb. 22 deadline.
On November 30, 2020, the Environmental Protection Agency announced it is aggressively addressing per- and polyfluoroalkyl substances (PFAS) in the environment. The agency announced two steps that it states would help ensure that federally enforceable wastewater monitoring for PFAS can begin as soon as validated analytical methods are finalized.
First, EPA issued a memorandum detailing an interim National Pollutant Discharge Elimination System (NPDES) permitting strategy for addressing PFAS in EPA-issued wastewater permits.
EPA’s interim NPDES permitting strategy for PFAS advises EPA permit writers to consider including PFAS monitoring at facilities where these chemicals are expected to be present in wastewater discharges, including from municipal separate storm sewer systems and industrial stormwater permits. The PFAS that could be considered for monitoring will have validated EPA analytical methods for wastewater testing. The agency anticipates being available on a phased-in schedule as multi-lab validated wastewater analytical methods are finalized. The agency’s interim strategy encourages the use of best management practices where appropriate to control or abate the discharge of PFAS and includes recommendations to facilitate information sharing to foster adoption of best practices across states and localities.
Second, EPA released information on progress in developing new analytical methods to test for PFAS compounds in wastewater and other environmental media.
In coordination with the interim NPDES permitting strategy, EPA is developing analytical methods in collaboration with the U.S. Department of Defense to test for PFAS in wastewater and other environmental media, such as soils. The agency is releasing a list of 40 PFAS chemicals that are the subject of analytical method development. This method would be in addition to Method 533 and Method 537.1 that are already approved and can measure 29 PFAS chemicals in drinking water. EPA anticipates that multi-lab validated testing for PFAS will be finalized in 2021. For more information on testing method validation, see https://www.epa.gov/cwa-methods.
EPA continues to expand its PFAS Action Plan to protect the environment and human health. To date, it has assisted more than 30 states in helping address PFAS, and the agency is continuing to build on this support. Across the nation, the EPA has addressed PFAS using a variety of enforcement tools under SDWA, TSCA, RCRA, and CERCLA (where appropriate), and will continue to protect public health and the environment.
The agency is also validating analytical methods for surface water, groundwater, wastewater, soils, sediments, and biosolids; developing new methods to test for PFAS in air and emissions; and improving laboratory methods to discover unknown PFAS. EPA is developing exposure models to understand how PFAS moves through the environment to impact people and ecosystems.
Related Information
This blog references information issued from the US EPA, Office of Public Engagement.
