Maintaining Gas Extraction System Pumps Saves Time and Money | SCS Field Services
September 7, 2021
Accumulating liquids are problematic for landfills taking sludges and other wet wastes not traditionally part of the incoming waste stream. Add to the mix increasing precipitation, and operators could be staring down the perfect storm—especially as they work to optimize their gas extraction systems. Here’s the challenge, explains Pete Carrico, SCS Engineers Senior Vice President and national expert on liquids management:
“Trash is porous, and the soils used for daily and intermediate cover usually aren’t, so liquid gets trapped between alternating trash layers as the landfill fills. These “perched” liquids can drain into well columns and block the slotted portion of the extraction well piping that withdraws gas from waste and into the gas collection system.”
Even a robust vacuum on the wells will not pull gas once pipes fill with fluid. With no path to move it from trash into the collection infrastructure, operators work harder to stave off odor and slope stability issues, among potential resulting problems.
The good news is they have a recourse to remove the liquids, unblock well perforations, and extract more gas. They do it by installing dewatering systems: an intricate network of pneumatic pumps, air lines to power them, and conveyance lines, also known as force mains, to remove liquid.
Manufacturers have designed and redesigned their pumps to try and address problems specific to landfill gas extraction systems. And the equipment does the job but requires meticulous attention and skill to keep all the moving parts going. These liquids are rough on pumps due to their harsh nature. The suspended solids and biological material they contain are the biggest challenges, and if the landfill has high temperatures, these liquids can heat up, further taxing the system, Carrico says.
“No pump indefinitely survives the challenging conditions you have in landfills. So, where we can make the biggest difference is with these maintenance programs,” Carrico says. You’re spending O&M budget on what provides the most impact.”
SCS uses dedicated, factory-trained pump crews who focus solely on operating and maintaining gas extraction dewatering systems. These crews help ensure the infrastructure functions as it should, and gas moves through well piping slots, into the gas header piping, and to the blower/flare station for beneficial end-use.
“Operations run more smoothly with these crews in place. An SCS field crew is as unique as each landfill. Our specialists have various skill sets, i.e., gas collection system monitoring, surface emissions monitoring, or pump maintenance expertise. That’s how we produce better outcomes in terms of pump performance. If you effectively maintain and repair the pumps, you will restore them to their designed specifications, pump more liquids, and with greater ease,” Carrico says.
The teams, who work on landfills across the country, stay busy. One site can have five to 300-plus pumps, each with multiple components, and they must be removed and cleaned frequently.
Replacing worn, fouled, or damaged components is an especially tedious and complex job.
Some wells are 70 to 100 feet deep. Pulling air lines, liquid lines, and pumps out from that depth is hard and requires special equipment to do safely. SCS crews know how to take them apart and put them back together; they don’t just lower them back in the ground after working on them. But hook them up to air and water lines and watch them work at capacity before returning them to service.
It’s a value add; with a good maintenance plan and the right crew, pumps can be kept at their designed specifications and run efficiently for many years. They can typically be cleaned and reset for a fraction of their replacement cost.
“We leverage our size and resources. We have a deep bench of in-house experts and engineers willing to share information to help with problems, which is important as conditions vary at each site, as can problems and solutions. So, it’s important not to do this in a silo but rather pull from our broader knowledge base,” Carrico says.
Technology helps too, especially with tracking, maintaining, and reporting progress to clients. A geographical information system (GIS) maps each well’s location, and pump technicians upload data corresponding to each one from wireless tablets almost instantaneously.
The ability to automate tracking and display critical information right away on a dashboard has increased our program’s efficiency. Technicians spend less time tracking and look at analyses of all the landfill conditions to know where to concentrate their efforts, Carrico says.
A few landfills are working to avoid pumping liquids altogether. They are building large gabion rock structures at the landfill’s base, with piping that connects to the extraction well system, creating a conduit. Liquids automatically drain to the bottom where leachate is intended to go while effectively pulling more gas into the gas collection system.
“This is a newer trend that some of our clients are already doing. And we are involved supporting the well designs,” Carrico says.
For now, in most cases, achieving the best outcomes is about investing in pumps and a good maintenance program.
“Monitoring and regularly measuring—checking stroke-counters, which show how many times a pump cycles, and checking flow meters to know how many gallons a day a system produces are key to finding savings. It’s how you reduce or prevent catastrophic failures,” says Greg Hansen, Senior Project Manager with SCS Field Services Operations, Maintenance & Monitoring.
To execute properly, Hansen provides this advice for operators setting up a pump program:
Have pump maintenance areas with water, electricity, disposal means for waste liquids, and storage facilities for spare parts and tools. More specifically:
Set up ample storage for spare parts inventory to avoid downtime. There may be 100 parts to a pump, and to replace them quickly, keep a parts inventory equal to about 10% of in-use pumps.
Know before you order parts which ones are compatible with your system as they are not all interchangeable. SCS can help with this.
Place the operation near leachate tanks so technicians can efficiently dispose of wastewater. Have cleaning materials analyzed to ensure they are acceptable according to the disposal permit.
Operators planning on doing maintenance in-house should train their technicians on cleaning, servicing, and testing pumps. Either SCS or the pump manufacturer can provide this training.
Above all, Hansen says, “You need a comprehensive OM&M program. The better the job tuning pumps, the better they do in the field, and the longer they work before being cleaned or repaired. It’s a continual process.”
Taming the Elephant in the Room – A Landfill’s Story of Leachate Treatment and Disposal
August 23, 2021
Landfill operators forever work to stay on top of a diverse and complex mix of leachate contaminants—heavy metals, ammonia, and biochemical oxygen demand, among them. But lately, they have more to think about, for one: how to keep concentrations of these contaminants within the wastewater treatment plant’s tightening discharge limits. Add to this concern the possibility of more compliance pressure as the list of constituents on regulators’ radar grows. Some operators are preparing for what may be down the pike, from microplastics to PFAS and PFOA—with the latter sometimes called the “elephant in the room.”
Among the strategies, some are exploring on-site leachate treatment options, and there are several. Finding the most fitting, sustainable, and cost-effective one takes vetting. Here is the study of a Florida landfill’s informed decision-making process.
A landfill serving an exploding residential and commercial population recently found itself in a predicament when the overburdened municipal wastewater treatment plant stopped accepting leachate from all county waste operations. Pressed to find a credentialed treatment facility quickly, this SCS Engineers client contracted with a private plant, but the arrangement came with a steep price tag. Overnight, the site’s leachate hauling and disposal costs rocketed from just over three cents a gallon to almost 16 cents a gallon. So, the operator turned to SCS Engineers for help vetting a robust and financially sustainable solution. Ultimately, the client wants to eliminate dependence on a third party and better control its destiny to avoid landing in the same predicament.
In answer, SCS is looking into the feasibility of a system that would clean leachate to drinking water standards to be discharged directly to groundwater. The team is wrapping up a comprehensive study of the site’s current operations, system, and leachate composition as it prepares the client to go out to bid.
“Our goal is to position the landfill to be as independent as possible while providing a cost-effective solution to their leachate treatment,” says SCS Engineers Project Lead Kollan Spradlin. He and the SCS liquid management experts backing him have kicked into high gear because time is money. Right now, the landfill generates about 70,000 gallons a day of leachate through much of the year. In the wet season, that figure spikes to about 150,000 gallons a day. At roughly 16 cents, the landfill can shell out over $24,000 a day for leachate disposal during the wet season.
SCS Engineers’ preliminary work begins with compiling crucial information around current leachate generation and future projections and around site-specific characteristics of the liquids. Next, the team vets multiple leachate treatment systems, sizing up each one against the client’s individual needs to ultimately make a recommendation. And, as important, the team makes sure the operator is very clear on how much upfront capital they need to build an effective, reliable system to do the job.
Spradlin and SCS’s liquid management experts are working on an interim solution while developing a long-term plan. The interim remedy is an evaporator fueled by landfill gas, heats and evaporates water molecules.
“With the evaporator, our client’s private disposal volume is reduced by 50,000 gallons a day, significantly cutting disposal costs. But that’s not enough. We want to reduce that expense further and to manage all or the vast majority of the leachate on-site,” Spradlin says.
The ultimate plan is to design a plant that can treat almost 120,000 gallons a day to a quality that can discharge across a spray field at the facility to groundwater. The landfill saves on disposal costs and owns the system rather than paying for an outside operator’s treatment technology.
This Florida landfill relies on SCS’s site knowledge and its past liquids management experience. SCS’ understanding of the systems and daily operations helped the team develop operational measures already reducing leachate generation to make on-site treatment an option.
“We have completed plan design and construction of their collection, storage, treatment, and disposal systems. And that helped to provide insight into reliable, long-term leachate disposal recommendations,” says Bob Gardner, a 41-year veteran of SCS and part of the team supporting this particular project.
“We had knowledge of site fill sequencing, site conditions, and constraints. And this sped up the process of coming up with a modification that works within their operations and infrastructure,” he says.
All of this foundational background is key to identifying client-centered solutions and presenting a comprehensive data package to vendors. “We give bidders the details they need so they can size their equipment appropriately and provide a more accurate budget estimate. We are trying to eliminate bidder change orders resulting from inadequate background information,” Spradlin says.
The team is thinking ahead, evaluating treatment processes that address a wide range of leachate properties and consider constituents that may be regulated in the future.
“We may put in a reverse osmosis system, a membrane bioreactor, or ultrafiltration to reduce constituent concentrations and take out particulates. We design for flexibility to add more treatment technology on the front end or back end to save the client infrastructure costs in years to come,” Spradlin says.
What differentiates SCS from some other environmental engineering firms is its full-service model and deep bench.
“We touch everything at this landfill. And we have a multidisciplinary team, including national liquid management experts whose knowledge we can tap into at any time. So, we can be one-stop, saving the client from having to go to multiple vendors,” Spradlin says.
Sam Cooke is the lead liquid management expert for this Florida landfill. Like his colleague, Gardner, he knows the wastewater treatment problems landfill operators face; he knows the vendors and their technology. And he understands the importance of relationships—with the client, the state agencies, and every party who is key to the client’s success and the community they serve.
“We fully realize that the wastewater-leachate treatment system we design needs to do its job close to 24/7/365. Moreover, it must do it effectively, sometimes under difficult conditions. So, as we design treatment systems and work with equipment suppliers, facility owners, environmental managers, and treatment system operators, we strive to provide added value and support,” Cooke says.
“In this case, we’re using our knowledge to help our client develop a bid package that addresses specific technical requirements but also meets and helps protect their business and financial goals.”
The team has already met with the regulatory agencies to develop a clear permitting path to accelerate plant deployment and ensure the landfill is fully compliant before making the large transition to direct discharge.
By working with vendors and regulatory representatives well before releasing bid documents, SCS has paved a path to leachate treatment independence.
Posted by Diane Samuels at 6:00 am
SCS Engineers Annual Landfill & Solid Waste Seminar for Pennsylvania
June 10, 2021
Join SCS Engineers for our 13th Annual Pennsylvania Landfill & Solid Waste Seminar on June 10, 2021. This half-day seminar is a FREE virtual event — open to solid waste professionals.
The seminar is designed to provide updates on the latest regulatory, policy, and technological developments in solid waste, landfill and landfill gas industries, and is intended for solid waste management professionals, landfill managers, waste/recycling managers, supervisors, and operators. For attendees already possessing landfill experience, topics will provide a fresh perspective and cover important regulatory and technological updates. For those new to the field, topics will cover essential information on all aspects of landfill development, operations, monitoring, and management. Opportunity for CEUs available.
The seminar will cover the following topics:
Liquids Management: What Are Our Options?, by Darrin Dillah, Ph.D., PE, & Parita Shah
Solar Opportunities on Closed Landfills, by Annika Colston, President & Founder of AC Power, LLC
Groundwater Sampling: Do You Know What’s Being Done at Your Site?, by Jennifer Robb
GIS, Drones, and RMC – Integrated Technologies for Sustainable Waste Management, by Cesar Leon & Joy Stephens
Landfill Odor Mitigation, Abatement, and Control Case Studies, by Bob Dick, PE, BCEE
Current and Emerging Issues in the Regulation of Solid Waste and Landfill Air Emissions, by Josh Roth, PE (SCS), Mark Hammond (Bureau of Air Quality Director, PADEP) & Jason Dunham (Environmental Engineer Specialist, PADEP)
Melissa Russo Thirsts for Knowledge and Enjoys Competition
June 3, 2021
When Melissa Russo’s boss Phil Carrillo told her he thought she should get her drone pilot license, she thought he was kidding. At the time, she worked on SCS’s Remote Control (RMC) team; selling drone services was a part of her job, but she had not thought of flying these unmanned vehicles herself.
Her thirst for competition kicked in when he turned the proposition into a bet. He was going after his pilot license himself; she bet she’d beat his score. They finished in a dead heat, but what started as friendly rivalry ended up bringing a new dimension to Russo’s job— a job that continues to expand in breadth as new opportunities turn up.
Today she not only flies, sells drone services, and teaches others how to sell and fly, but she’s helped bring geographical information systems (GIS) into RMC’s portfolio. How these technologies fit together is RMC remotely collects data from drones and different landfill systems. Then the GIS translates that data into maps, capturing a visual picture of how clients’ facilities’ systems are performing. The GIS piece is one of the latest chapters in the story of Russo’s evolving role (more to come on that).
Piloting is what especially gets her juices going.
“I love working with my team, supporting them in what they do. But when it comes to drones, I like the hands-on experience of flying myself more than telling other people how to do it.”
She controls these small aircraft from a device on the ground, sharply focused on her surroundings while keeping the drone in her sight at all times.
“You have to make sure there are no manned vehicles around; they have the right of way. And there’s a lot of continuous movement on landfills. You’re constantly aware of your surroundings. Is a truck coming? Am I in line with where dumping is going on?”
Flying drones takes muscle and mechanical aptitude.
The drone and case can weigh 45 pounds. And there are a lot of moving parts to assemble and calibrate.
Sometimes it’s manual work, pointing and rotating a remote controller to send a radio signal to tell the drone what to do. But more often, she pilots automated flights that she maps in advance and uploads the flight path specs into software that interfaces with the drone.
“When I’m flying drones, I can access areas where if I had boots on the ground, I couldn’t. I can go and explore just about anywhere, similar to when I dream— only it’s real,” she says.
With any task, she’s laser-focused, concentrating on one part of the picture at a time to grasp the details. She steps back and uses critical thinking, accumulated knowledge, and imagination to take on what’s before her.
The innovation process
“We’re pretty lucky with our timing; new and proven technologies are emerging quickly. I’m one of many SCSers with a deep knowledge of technology and practical experience in the solid waste industry. Together, we can make a difference because we understand the business and operational challenges very well. When I need an expert in another industry, I just reach out to a colleague. The learning process never ends, and each project helps me and my team constantly find better answers.
“My boss is more of a big-picture person; his ideas are huge and amazing. He comes to me with new ideas, and I figure out how to make them work and implement them,” Russo says.
She points to his idea to use proven GIS technology within RMC. She was already using GIS to map methane data, process topographic maps, and stockpile calculations. For instance, she integrates methane values into the GIS and overlaps them with imagery so her clients can zoom in on one well or get a large-scale view of the overall health of the gas collection system. But integrating GIS in new ways to incorporate multiple landfill systems would solve some expensive problems and, better yet, prevent even more expensive mitigation and repairs.
Expanding GIS applications to illustrate multiple landfill systems
“I know drones and how to process drone data. But now that we are expanding applications, I add more layers of landfill data, such as liquids, soil, the gas collection and control system (GCCS), SCADA, and surface emissions, to bring them into the RMC GIS platform. My colleagues are demonstrating these technologies at the SCS June Client Webinar.”
“I created a team of hand-picked SCS staff with both GIS and waste management backgrounds (and a whole lot of drive) to make the vision come to life,” she says. “That’s how we innovate, tight teams with access to nationwide expertise.”
Within six months of the project’s genesis, Russo and her team had integrated gas and liquid collection systems, other landfill systems, and asset management into the RMC GIS platform. She and her team now sell these applications nationwide.
Russo’s come a long way since joining SCS at age 21
In her mind, she grew up at the company. Before coming on board, she managed a shop in Manhattan Beach, California, while she began thinking about what to do next.
“I learned a lot about business and people. It was a stepping-stone – I discovered how to earn trust, build rapport, and sell. But in time, I decided I wanted a more professional job,” she recalls.
She went to work for a real estate company managing the SCS Engineers Long Beach office, where she would soon take an entry-level Accounts Payable position in SCS Field Services.
In time, she transitioned to the Health and Safety group, assisting in creating training material and managing truck fleets. Soon she was managing assets, among other firsts for her. By this point, she had developed enough software, accounting, and other administrative skills to step up fast.
Part of the job was keeping up with vehicle maintenance, so she often spoke with field staff. Many of them she already knew from her days working in the accounting department.
Growing with her SCS colleagues
“When I was in my first administrative roles, I supported many colleagues who were field techs or supervisors; they are project managers now. It feels as though we’ve grown up together, and we know and trust each other. We collaborate well and know that when we bring projects to each other that we will take care of each other,” Russo says.
She especially likes the RMC concept because remote control and automation enable her, her clients, and her team to work smarter, not harder because they leverage the technology to work for them.
“That means we can usually work from anywhere, giving all of us more time for family, friends, or allocating the time saved towards other needed to-dos. I’m up at five a.m. and, at times, may not finish work until nine at night. Somehow, us working women find the balance in between meetings, writing proposals, and answering emails; I have lunch with my two boys or take them to a park,” she says.
Bambi Lance, a veteran SCSer and her mother, works in the same business unit as Melissa does. “Mom’s been here for 16 years, and it’s interesting to have her perspective not only as my mom but as someone who knows SCS. She knows my department, and she knows me. She sees what I am doing and she along with management encourage me to do more and believe in myself.”
Russo reflects again on the concept of stepping-stones on the way to knowledge and maturity. I’m competitive and take on challenges, which has been a driving force in all I do today. It’s helped me take a personal inventory of how I am now versus the young Melissa,” she says.
She uses it to gauge her direction. And she uses it to connect to her staff. “I try to help them see you can turn almost any experience, into a positive. I want my team to see we are all learning and growing. They can, as I can, comfortably bring new ideas to the group and company, which often turn into new ways to help clients.”
She circles back to her decision to fly drones, explaining how it aligns with her career path from her first steps to today. “Becoming a pilot was a natural fit because it’s a new challenge. The craving to take on new tasks is how I grew from an accounting administrator to a project coordinator up to a business manager. It’s wanting to expand my knowledge, tackle new feats, and accomplish what I was not sure I could do. I like the challenge.”
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.
Onsite Landfill Leachate Management: To Treat or Not to Treat…
March 29, 2021
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 Latimerand 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.
SCS’s leachate management team is available to answer your questions on this blog or our other treatment designs at
Posted by Diane Samuels at 6:00 am
Wastewater: Helping a Meat Manufacturer Overcome It’s FOG Problem
March 10, 2021
Not long ago, a Utah food manufacturer turned to SCS with a persistent problem: high concentrations of fats, oils, and grease (FOG) in its wastewater— high enough to clog the city’s sewer line, knock it out of compliance, and cost it a steep surcharge year after year. As the plant worked toward a solution, its customers’ demand was growing; it reached a point where it had to expand to keep up, and that’s when the quandary came to a head. The meat processor couldn’t get a permit for expansion until the FOG was in check.
Within 18 months, SCS Project Director Mark Pearson and his team of liquid management gurus had their client within acceptable discharge limits for the first time in years. Actually, the plant’s doing a lot better than meeting the city’s requirements. Its FOG concentrations, which had spiked to thousands of mg/L, are consistently down below the established discharge limit of 200 mg/L.
The scenario Pearson walked into is that the wastewater generation and pollutant loading were highly variable as flows fluctuated. Due to hydraulic limitations, the treatment system couldn’t keep up with volumes during peak flows. As a result, the influent (untreated wastewater) was discharged from the plant to the sewer to the municipal wastewater treatment plant. And because the system was overtaxed, it did not sufficiently break down the FOG, which exacerbated the problem, wreaking havoc with the city’s collection pipes.
After completing the initial assessment, Pearson’s team developed a multifaceted approach to debottleneck the system’s hydraulics and make other improvements to increase FOG removal efficiency.
Pearson; Dean Free, senior project manager; and Nathan Hamm, program lead for wastewater and liquids management, came up with a design that achieves two main goals: It eliminates uncontrolled discharge from the plant; it greatly reduces concentrations of FOG—cutting the contaminant load to the city. Not only is the client within discharge limits, but it’s also pushed through its most immediate barrier to expansion permit approval. And it’s improved its relationship with the city.
The solution is a complex one involving chemistry, mechanical engineering, and electrical engineering. But to pare a lot of fine details down to the nitty-gritty, Pearson says:
“We put in screens that remove solids in the wastewater. We constructed a 60,000-gallon tank to equalize the flow coming to the plant. We adjusted pH to help optimize the wastewater treatment chemicals’ effectiveness. We separated the influent tank from the effluent (treated water) pipes to solve a problem where the influent would overflow into the effluent through a perforated wall. The new piping setup makes overflow impossible. And to further fortify the system, we installed a lift station to capture previously untreated wastewater.”
As a bonus, the team installed a tank that the separated FOG residual is pumped to, then hauled to a compost facility for beneficial use.
Besides adding these system enhancements, the SCS team took capabilities further with a process control and instrumentation component. The technology monitors flow rates, temperatures, tank levels, and other conditions. It processes the data and automatically makes adjustments to achieve treatment goals, avoid production downtime, and enable operators to respond proactively should they see a red flag.
Comparing the old to the new way of monitoring and analyzing, Pearson says, “What our client had before was rudimentary information. And while they could monitor conditions, they had to walk around the plant. All of the operational data can be viewed on a screen now from one location. They have more data at their fingertips and more capability to make adjustments to avoid discharge exceedances.”
The wastewater treatment system upgrade was done as a design-build to speed the timeframe while also increasing efficiency. “We could immediately start rather than put it out to bid. We could do construction as we designed. And there was one entity and one point of responsibility. So what’s cool is we leverage both SCS engineering and construction capabilities to solve problems,” Hamm says.
He and his colleagues have the know-how to pivot on a dime if they have to, and there were a couple of times it was necessary, including when the client brought new management on board midway through the installation process. The new team preferred different instrumentation and had a specific scheme in mind.
“We were in the process of installing the original instruments. But we were able to incorporate their equipment preference midstream. We had to figure out how to get new instruments installed and ensure they were perfectly integrated with the computer control system that takes readings from the instruments. It was what they wanted, so we saw that they got it,” Pearson says.
While he and his co-workers’ jobs as project design and build engineers are done, they have not faded from the picture. They provide ongoing technical support when the client needs assistance with troubleshooting. The automated control system has helped.
“This is a robust and complex mechanical treatment system. If by chance, something was wrong, our client can transmit data that comes out of the process controller so we can work remotely to determine if process changes are needed. If they are, we can often make those changes from offsite, and quickly,” Hamm says.
But the SCS team also plans so that its client is equipped to ensure its success moving forward. They provide operator training. And they developed a standard operating and maintenance procedures manual and a checklist to track data and activities transferred from shift to shift, providing operators a standard and seamless way to communicate.
The busy Utah plant is on a good trajectory, with solid footing.
Says Pearson: “Before, they could not expand the plant or even continue their operations much longer if they did not get the FOG under control. Now they can operate continuously, discharge to the city, and they have potential to expand their plant because they are showing the regulators they can stay within their permit limits.”
SCS Engineers Annual Landfill & Solid Waste Seminar for Maryland
February 4, 2021
Join SCS Engineers for our 18th Annual Maryland Landfill & Solid Waste Seminar on February 4, 2021. This half-day seminar is a FREE virtual event — open to solid waste professionals.
The seminar is designed to provide updates on the latest regulatory, policy, and technological developments in solid waste, landfill and landfill gas industries.
The seminar is intended for solid waste management professionals, landfill managers, waste/recycling managers, supervisors, and operators. For attendees already possessing landfill experience, topics will provide a fresh perspective and cover important regulatory and technological updates. For those new to the field, topics will cover essential information on all aspects of landfill development, operations, monitoring, and management. Opportunity for CEUs available.
The seminar will cover the following topics:
Liquids Management: What Are Our Options?, by Darrin Dillah, Ph.D., PE, & Parita Shah
Maryland Regulatory Update, by Jacob Shepherd, PE
Best Available Control (BACT) for Landfill Gas Collection Systems: What Does This Look Like in 2021?, by Bob Dick, PE, BCEE
Efficiency Assessments for Landfill & Other Solid Waste Facility Operations, by Daniel Jansen
Groundwater Sampling: Do You Know What’s Being Done at Your Site?, by Jennifer Robb
How Recycling Programs Have Adapted and Improved in Response to Difficult Market Conditions, by Brent Dieleman
Complementing the Interstate Technology and Regulatory Council’s – ITRC, PFAS Technical and Regulatory Guidance, the website now has ITRC Per- and Polyfluoroalkyl Substances – PFAS, and Risk Communication Fact Sheets available. The site and updated content replace older fact sheets with more detailed information and useful for those who wish to understand the discovery and manufacturing of PFAS, information about emerging health and environmental concerns, and PFAS releases to the environment with naming conventions and federal and state regulatory programs.
SCS Engineers’ professionals recommend further reading to understand specific chemicals or subgroups of chemicals under study to comprehend PFAA behavior in the environment. There are appropriate tools to develop a site-specific sampling and analysis program and considerations for site characterizations following a PFAS release.
Firefighting Foams – Aqueous film-forming foam (AFFF) users and those who manage AFFF releases.
The Interstate Technology and Regulatory Council (ITRC) is a state-led coalition working to reduce barriers to the use of innovative air, water, waste, and remediation environmental technologies and processes. ITRC documents and training can support quality regulatory decision making while protecting human health and the environment. ITRC has public and private sector members from all 50 states and the District of Columbia and is a program of the Environmental Research Institute of the States (ERIS), a 501(c)(3) organization incorporated in the District of Columbia and managed by the Environmental Council of the States (ECOS).
National paradigm shifts for using new technology
Harmonized approaches to using innovative technology across the nation
Increased regulatory consistency for similar cleanup problems in different states
Reduce the review and permitting times for innovative and proven approaches to environmental prevention and mitigation programs
provides Prevention with Risk Management, Process Safety, and Spill Prevention Plans
Can help reduce the possible impact on environmental insurance
Faster cleanup with less environmental impacts
Decrease compliance costs
Provides technical and regulatory expertise for public outreach
Regularly engages with state and federal regulators and compliance enforcement as a trusted engineering firm.
Posted by Diane Samuels at 6:00 am
Emerging Design Concepts to Facilitate Flow of Liquids on Landfills
May 11, 2020
The industry is designing and building more substantive drainage features and larger collection systems from the bottom up, that maintain their integrity and increase performance over time, thus avoiding more costly problems in the future.
Waste360 spoke with three environmental engineers about what landfill operators should know about liquids’ behavior and what emerging design concepts help facilitate flow and circumvent problems such as elevated temperature landfills, seeps, and keep gas flowing.
The engineers cover adopting best practices and emerging design concepts to facilitate flow. They cover topics such as directing flow vertically to facilitate movement to the bottom of the landfill, drainage material, slope to the sump percentages, vertical stone columns, installing these systems at the bottom before cells are constructed, and increasing cell height to prevent the formation of perched zones.
Ali Khatami, one of the engineers interviewed, has developed standards for building tiered vertical gas wells that extend from the bottom all the way up. He frequently blogs about landfill design strategies that his clients are using with success. His blog is called SCS Advice from the Field. Dr. Khatami developed the concept of leachate toe drain systems to address problems tied to seeps below the final cover geomembrane. These seeps ultimately occur in one of two scenarios, each depending on how the cover is secured.
Landfill Gas Header: Location and BenefitsBy continuing to design gas header construction on landfill slopes, all of the components end up on the landfill slope as well. You can imagine what type of complications the landfill operator will face since all of these components are in areas vulnerable to erosion, settlement, future filling, or future construction. Additionally, any maintenance requiring digging and re-piping necessitates placing equipment on the landfill slope and disturbing the landfill slope surface for an extended period.
AIRSPACE, the Landfill Operators’ Golden EggAirspace is a golden egg, the equivalent to cash that a waste operating company will have overtime in its account. With each ton or cubic yard of waste received at the landfill, the non-monetary asset of airspace converts positively to the bottom line of the …
Gas Removal from Leachate Collection Pipe and Leachate SumpKeeping gas pressure low in and around the leachate collection pipe promotes the free flow of leachate through the geocomposite or granular medium drainage layer to the leachate collection pipe and improves leachate removal from the disposal cell. Using gas removal piping at leachate sumps is highly recommended for warm or elevated temperature landfills where efficient leachate removal from the leachate collection system is another means for controlling landfill temperatures.
Leachate Force Main Casing Pipe and Monitoring for LeaksLandfill operators may add a casing pipe to their leachate force main for additional environmental protection. Consequently, the leachate force main is entirely located inside a casing pipe where the leachate force main is below ground. In the event of a leak from the leachate force main, liquids stay inside the casing pipe preventing leakage …
Pressure Release System Near Bottom of LandfillsPressure Release System Near Bottom of Landfills – Essential Component for Proper Functioning of the Landfill Drainage Layer. Landfill designers are generally diligent in performing extensive leachate head analysis for the design of the geocomposite drainage layer above the bottom geomembrane barrier layer. They perform HELP model analyses considering numerous scenarios to satisfy all requirements …
Landfill Leachate Removal Pumps – Submersible vs. Self-Priming PumpsSelf-priming pumps can provide excellent performance in the design of a landfill leachate removal system. Landfill owners and operators prefer them to help control construction and maintenance costs too. A typical system for removing leachate from landfill disposal cells is to have a collection point (sump) inside …
Posted by Diane Samuels at 6:00 am
3900 Kilroy Airport Way Ste 100
Long Beach, CA 90806-6816