Save the date! Waste360 is hosting its Global Waste Management Symposium, February 14-17, 2022 at the Hyatt Regency Resort & Spa in Indian Wells, California.
The program is taking shape and will feature numerous sessions on solid waste and materials management, such as waste minimization and reuse, landfill operation and design, organics diversion/composting/anaerobic digestion, elevated temperature landfills/subsurface reactions, climate change, greenhouse gas emissions, sustainable materials management, wastes from energy production (e.g. coal ash), waste containment and geosynthetics, odor emissions and management, leachate treatment, recycling and material markets, landfill gas production, waste-to-energy, waste characterization, and more!
GWMS services the needs of landfill owners and operators, as well as their engineers and the consultant and vendor communities. Join this broad coalition of participants that also includes:
Sponsorship opportunities are currently available.
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.”
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.
The Michigan Water Environmental Association (MWEA) is hosting its 96th Annual Conference, June 27-30. This is a virtual/in-person hybrid event with options for virtual participation or in-person attendance at the beautiful Boyne Mountain Resort.
The conference will feature sessions on Collections, Climate Resiliency, PFAS, Utility Management, Residuals and Biosolids, Watershed and Stormwater Management, other important topics, and fun activities, including a golf scramble water activities, receptions, exhibitors (outdoors in tents), and more.
SCS Engineer’s Remote Monitoring Control specialist, Brett Heist, is co-presenting on “More Than a Pretty Map – GIS Covers Your Assets” (Session 1A: Collections, Monday, June 28 at 1:00 pm)
We have a GIS map; now what? This presentation will highlight how to utilize GIS platforms and expand on them in new and creative ways to help leverage functionality and maximize the availability of information. For 2D (horizontal) assets, there are some unique methods to plan for capital improvements and streamline data storage and access. Below are a few examples that are being implemented in the City of Zeeland:
Like most major cities and townships, the City has a comprehensive GIS map for its Storm, Sanitary, Water, and Streets. This map includes information about each asset within the system: material, size, inverts, condition, business risk, and even televised inspection videos for some of the storm and sanitary lines.
This information was combined into a comprehensive capital improvement map that the City uses to plan for 5-year improvements, significantly improving planning and budgeting efficiency while ultimately providing the public with safer infrastructure.
The televised inspection videos are immediately attached to the respective asset once uploaded to a cloud-based storage system from the field. All of this information is accessible at the click of a mouse, available anywhere with an internet connection.
For 3D (Vertical) assets, you can access entire buildings in the same manner as horizontal assets inside a 3D online viewer. Some examples that this presentation will highlight include:
To summarize, utilizing GIS platforms to their maximum potential enhances the efficiency of maintenance/inspection activities and improves the reliability of physical infrastructure throughout a community, leading to increased public safety and financial savings.
The MWEA Conference covers a wealth of other important topics on water management.
The 79th Annual Conference is one of the Midwest’s largest gatherings of safety and health professionals. It is the perfect opportunity for decision-makers to find new products and services, and learn more about the environmental concerns they are facing. SCS Engineers’ Cheryl Moran is attending; she looks forward to meeting and greeting you soon! Cheryl is ready to share her industry expertise with colleagues and peers on safety.
Half-day sessions starting at 8:00 am on Tuesday, April 20, 2021 – Thursday, April 22, 2021
Wednesday at 10:00 AM join us at Session #17 PFAs – An Update On This Emerging Contaminant
Tony Kollasch, Project Manager, and Jeff Marshall, Vice President, National Expert on Innovative Technologies, SCS Engineers discuss the history of PFAs, why people are concerned about PFAs, the current state of environmental
regulations regarding this substance, and the likely future of PFAs concerns.
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.
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.
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.
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.
The Remediation Technology (RemTEC) Virtual summit will take place March 9-11, 2021.
RemTEC will be much more than your typical video-based virtual conference. Their robust virtual platform will provide a seamless experience of educational sessions, networking opportunities, custom-built exhibitor booths, and much more.
The Conference Keynote will feature a panel discussion on “Lessons Learned and What’s Next for Site Remediation from Industry Titans.”
The conference will feature several Tracks: