FREE, OPEN FORUM WITH Q&A
The EPA, industry, and landfills are under an emissions microscope feeling greater pressure to measure and minimize greenhouse gas emissions. There is a wide range of carbon sequestration solutions in the marketplace; most break down into two categories geologic and biologic. Biologic carbon (CO2) sequestration encourages plant growth to remove CO2. It is a logical solution, but not fast enough to provide advantages that landfills and industry need now.
Ray Huff and Monte Markey provide a “birds-eye view” of the CO2 sequestration marketplace, how it works, and the options relevant to landfills. Ray and Monte will discuss geologic carbon sequestration using deep well injection during SCS’s January forum.
Sessions are interactive with Q&A throughout and in the last quarter of the time allotted. As always, these are non-commercial, and your privacy is protected. Anyone who RSVPs will receive the recorded video following our live session.
Following registration, look for a Zoom email with your private link to join at 2:00 PM Eastern Time for this one-hour session (1:00 Central, 12:00 Mountain, 11:00 AM Pacific). Please do not share this private link with others as it may disrupt your ability to log in.
The Fabricated Geomembrane Institute – FGI, discusses allowable leakage rates for industry. We strive for zero leakage and it is possible – this mix of regulators and practitioners including Neil Nowak of SCS Engineers discuss how to achieve it.
Click here to start the video.
The promulgation of 40 CFR 62 Subpart OOO (EG plan), effective since June 21, 2021, impacted all MSW landfills operated under NSPS subpart WWW. One of the major changes of this rule is the requirement to monitor all cover penetrations during quarterly methane surface emission monitoring (SEM). All components that are part of the landfill gas collection system and any other object that completely passes through the landfill cover are considered cover penetrations.
As landfill and landfill gas practitioners, we suggest that advanced planning can save you time and effort. As landfills face short 10-day correction periods, coupled with supply chain and labor shortages, planning can make operations and compliance more efficient. We present a few scenarios and suggestions here.
You’ll need to record any reading greater than 500 ppm above background as an exceedance location during monitoring. These require taking corrective actions such as cover maintenance or landfill gas wellfield adjustments, along with monitoring the exceedant locations again within 10-days of your initial monitoring. If 10-day monitoring still shows methane concentrations greater than 500 ppm, you’ll need additional corrective actions and to monitor the location once more within 10-days of the second exceedance.
Once the location(s) shows methane concentrations less than 500 ppm, it is mandatory to monitor these locations again one month from the very first reading showing the exceedance. If a location shows methane concentration greater than 500 ppm for three occasions in one quarter, the addition of a collection device, other improvements to the collection system, or a request for an alternative remedy and timeline is required. Therefore, implementing appropriate corrective action within the specified timeframe is critical to avoid expensive GCCS expansions or NOVs.
Gas well, well boots, leachate risers, below and above-grade pipe transition, condensate sumps, and valve vaults are some of the common exceedant penetration locations. Implementing corrective action at these penetrations within the given timeframe is a challenging ordeal for landfill operators. Corrective action can vary depending upon several factors: the methane concentration observed during initial monitoring, the location of the penetration, cover type (geomembrane capped vs. soil capped), material availability, and resources available to perform the work.
Corrective actions have varying material and effort requirements; one solution cannot fit all challenges. The most common corrective actions include applying expanding foam, soil mounding, excavation, clean dirt fill or bentonite fill, well boot repairs, installing a prefabricated well boot seal, and installing a vacuum line for emission control. We recommend before starting your monitoring operators consider the following factors:
Develop an educated estimate for the number of expected exceedant penetrations from the landfill sections that historically show cover exceedances or are in areas with problematic operating conditions. Using the readings and data collected over time makes identifying these areas much easier.
Decide the type of corrective action to implement based on your cover type in those expected exceedance locations.
Procure corrective action materials such as bentonite, geomembrane for boot fabrication matching permitted cap material, or prefabricated seals before you need them.
Check the availability of contractors for liner or well boot repairs, and their response time, before you need them.
Surface emissions vary based on the operating conditions; therefore, it is common to see a variable number of exceedances from one quarterly monitoring event to the next. At one of our sites that had no surface exceedances observed during the previous quarterly SEM event, multiple penetrations observed methane concentration greater than 500 ppm during the following quarterly event. One section of the landfill with a soil cap observed methane concentrations up to 16,000 ppm. The geomembrane capped section observed penetration concentrations of up to 8,000 ppm methane. We implemented various corrective actions to bring these exceedant locations to compliance.
In the soil-capped section, we implemented bentonite plugs, prefabricated seals, and site fabricated geomembrane seals depending upon the observed methane concentration, exceedant location, and material availability. Pre-planning and procuring material ahead of time proved to be very helpful.
For each of these corrective actions, we opened an area about 2-ft deep and 10-ft x 10-ft. For bentonite corrective action, about a 9-inch thick bentonite slurry was filled, extending about 5-ft on each side of penetration and then filled with clean dirt.
Prefabricated seals that come in standard sizes as a slip-on for penetrations and site-fabricated geomembrane seals also covered at least a 5-ft x 5-ft area around each penetration. The sleeves at each penetration were left at least 6-inch over the ground surface after filling the excavated section with clean dirt.
In the geomembrane-capped section, we choose to use well boot repairs using geomembrane. Our task was to identify the type of geomembrane used in the cap, procure the geomembrane, identify and schedule the contractor, and install well boots in each exceeding penetration location within the 10-day timeframe. After the well boot fabrication and installation, we needed to carefully reconnect the existing drainage layer.
Implementing these corrective actions can get expensive; prefabricated seals can cost up to $300 per penetration, excluding installation. Material and contractor’s availabilities are also a significant challenge. While implementing these corrective actions, additional unforeseen challenges can arise as well. Planning ahead and having the material on site is very important for landfill operators to keep the landfill under compliance.
About the Authors:
Shrawan Singh, Ph.D., PE, is a Senior Project Professional. Stephen Descher is a Senior Project Professional. You can reach both at SCS Engineers.
SCSeTools® – Developed by Landfill Gas Practitioners for Landfill Owners and Operators
The Birth of LFG Data Tracking
In the early 2000s tracking landfill gas data at facilities was anything but uniform, organized, or secure. The industry was using various methods to track data on paper forms and logbooks, then transferring it by hand into spreadsheets. Some of us used desktop database applications, but as the saying goes, necessity is the mother of invention.
From an SCS employee’s idea for demonstrating how to use landfill gas monitoring data to analyze and pinpoint system corrections, SCS DataServices® was born. In the span of several months, a team of SCS’s landfill engineers, field technicians, and technology gurus worked with client-needs to create a concept application visualizing collected landfill data on maps. Our staff field-tested it with good results, and SCS Field Services began using the application to visualize issues with wellfields that aren’t readily apparent when looking at spreadsheets.
A large SCS landfill client had seen our field staff using DataServices, asked if SCS would consider providing them with access to the application on a subscription basis. Our team adapted DataServices, added features, and continued improvements tailored for the client’s use.
As soon as secure data transfer became feasible, SCS moved to an Internet-based solution for our landfill gas practitioners. The platform called SCSeTools® holds the data collected by SCS DataServices®.
Applications and features roll out as we continually update and upgrade, incorporating ideas and improvements from our users and staff along the way. DataServices is addressing the landfill gas management needs of over 600 landfills across the US and Canada in 2021.
The keys to success follow our mission and values of maintaining close communications with our clients, field staff, engineers, and eTools support staff (all landfill gas practitioners), with the help of software engineers. Technology companies are not up at night thinking about landfill operations, but we are.
We introduce our SCS eTools landfill technology capabilities and a few of the creative and talented SCSers behind the technology in the next segment. Our speakers walk you through demonstrations of how over one-third of the landfill owners and operators in North America are increasing efficiencies using SCS eTools.
Visualizing Landfill Challenges – Shortcuts to Keeping Your Wellfield in Balance
DataServices shows the entire wellfield for any monitored parameters and zooms in on troublesome areas or wells. Results can be as simple or detailed as the landfill owners’ environmental and business needs dictate. The detailed examples here illustrate how graphs, maps, and charts help keep the wellfield in balance. We link each challenge to the description of a video demonstration.
In balance means extracting more gas for renewable energy, preventing odors and methane migration, keeps subsurface and surface conditions and workers safe. The information can help diagnose equipment conditions before they become costly, maintain regulatory compliance, and support cost estimates if the landfill is expanding or more infrastructure investment or equipment is needed.
Looking at vacuum distribution across a gas collection system – Select the system pressure map, which highlights vacuum distribution across the wellfield to show the wells with good (expected) vacuum, pressure drop over distance, and any wells unexpectantly losing vacuum. Zooming in and changing the vacuum ranges further enhances where to assign staff to troubleshoot any identified issues.
Using a methane distribution map shows whether the wells are tuned to where the landfill owner wants them. Wells may be identified below the targeted range, indicating slight over pulling; a technician can use this map to identify such issues and quickly check the identified wells. Wells identified above the desired methane tuning range indicate wells not collecting enough gas, which has consequences. These wells can be the source of odors, leachate seeps, possible lateral migration to an out of waste probe. Not sending enough fuel to a power plant or atmospheric releases can affect surface emissions monitoring.
Managing liquids – Changing waste streams and more rainfall in certain areas of the country complicates liquids management. DataServices visualizes the impacts of liquids on wells and helps landfill owners better manage a proper liquids removal program. The program will let them know how many pumps to budget for and, over time, where to relocate well dewatering pumps so that they are most efficient at removing liquids from landfills.
High-BTU Gas Plants –Filter maps help users locate wells contributing to gas dilution into renewable energy plants. It can help create punch lists for landfill staff to investigate, troubleshoot and tune. As wellfield technicians make corrections, they show on the map in real-time.
Temperature and subsurface oxidation events – Some call the condition subsurface fires, but this is a serious issue for landfills. Over-pulling wells, damaged infrastructure, and other conditions can cause oxidation events. Using a combination of temperature Parameter Maps to review wellhead temperature distribution and a Points Chart feature provides a deeper dive into the data. It provides more insight into which well or wells may be contributing to the high-temperature issues.
Locating a specific well – That’s not so easy when hundreds of wells surround you and at larger landfills. DataServices had built-in filter features to identify a single monitoring point on a wellfield map easily.
Customizing for compliance, best practices, and rules – DataServices allows monitoring points across a single site to have customized rules for each monitoring point. Rules can be for regulatory purposes, standard operating procedures, best management practices, and even site-specific preferences or any combination thereof. It is efficient to customize rule application to landfills and collection points – meaning wells, probes or ports, horizontal collectors. This customization capability helps organize and confirm regulatory compliance. It is especially salient with the 2021 EPA and state compliance changes for a single landfill or an organization with hundreds of landfills.
MobileForms – Inspection forms, blower flare station monitoring forms, load tracking from municipalities, incoming hazardous waste tracking, MRF bale counts are examples of paperless entry available. The data feeds directly from mobile phones to the supervisor and into the maintenance department, so staff can start cataloging and looking at what’s going on in real-time at several types of facilities. It’s available for regulators and inspections and helps reduce staff hours tabulating and centralizing the information. Any information historically captured on a form or log attached to a clipboard can now be captured and stored electronically. From there, it can be recovered and produced as a PDF export file or data from the forms used to trend data and help make informed operational decisions.
MobileTools – DataServices in a condensed format suitable for mobile devices. Field staff use MobileTools to save time formerly used to return to the office, transfer/transcribe the collected data and upload it to a supervisor for quality checks before storage. Technicians can now recall the last 20 readings for any given well and review trend graphs on their phones or tablets while standing adjacent to the well they have questions about and need to access the data. MobileTools also allows them to upload field data such as liquid level readings while the data is being collected. The information instantly populates into DataServices and is available for review by others on the project team.
The most valuable tools are in development now for release in 2022. ARC GIS integration developed under SCS RMC® will further enhance DataServices with even better visualization and location capabilities and provide enhanced features such as allowing landfill owners to see their well as-built information and view subsurface information about their wells.
Learn more at SCS Engineers, where we adopt our clients’ environmental challenges as our own.
In October, Republic Services’ Otay Compost Facility at the Chula Vista, California, Otay Landfill opened for business. The compost facility helps communities in San Diego County meet the requirements of California’s SB1383 law mandating the diversion of organic waste from landfills.
The composting facility designed by SCS Engineers in collaboration with Sustainable Generation operates completely off the grid using solar energy. It is the first fully solar-powered compost facility in the state and can process 100 tons of organics per day, with plans to double capacity by year-end.
Both organics recycling and reuse leaders, Republic Services hired SCS Engineers to design the Otay Compost Facility. The design uses renewable energy to run 100 percent of the composting operations at the site. The facility design includes using technologies to speed the maturation rates and reduce excessive odors. Blowers to aerate the organic material, oxygen and temperature sensors, and advanced compost cover technology produce a high-quality product.
“Republic’s taken the goals of SB 1383, to reduce emissions of short-lived climate pollutants further. They’re running a sustainable facility that enables residents, businesses, and government to easily reuse and recycle more within a smaller carbon footprint than ever expected,” says Vidhya Viswanathan, engineer and project director.
As California collects and recycles organic materials from homes and businesses, local governments will use the products made from recycled organic material for compost and mulch. Recycling organic waste into compost creates a nutrient-rich soil amendment, preserving natural resources and reducing water consumption working within a circular economy. This California jurisdiction is ready for the SB1383 deadline on January 1, 2022.
“Republic Services supports California’s effort to divert food and yard waste from landfills to facilities such as this one,” said Chris Seney, Republic’s director of organics operations. “We’re grateful to SCS for their partnership in helping us bring this facility, co-located at an active landfill, to reality.”
Please watch the YouTube video to see the facility and learn more about its environmental value.
SCS Engineers is proud of helping our municipal and private clients bring the most value to their environmental solutions and communities. To learn more about SCS Engineers, view our 50th-anniversary video.
Hydrogen sulfide (H2S) levels are creeping up at some landfills, especially those that take C&D waste; some are seeing concentrations in the thousands to 30,000 parts per million (up from about 20 to 40 ppm ten years ago). And even at very low concentrations, H2S can be problematic.
Material Recovery Facility residuals, which typically contain significant amounts of pulverized drywall, are high in gypsum and sulfate. Once broken down, residuals become a high-surface-area material, leaching into and spreading through waste. When reacting with water and organics, it can potentially generate H2S. With a drive to divert more C&D debris, and regulations tightening around H2S, operators’ jobs get harder as they work to stave off emissions from this corrosive, flammable compound notorious for its “rotten egg” odor.
When building out their gas collection systems, controlling H2S becomes even more daunting. Sol Sim, an SCS Engineers Vice President, explains, “We see H2S concentrations jump when we expand landfill gas collection systems, often in cells that contain C&D residual screening materials. The gas was there all along but sequestered. Now it’s coming out of the ground, and the onset of issues can spike suddenly.”
When spikes come on quickly, Sim’s team implements turnkey interim treatment approaches. They start by identifying the gas collection wells with the highest contributors and act fast to get them into compliance.
SCS teams take a two-pronged approach by stepping back and thinking about the big picture while taking action. It provides a major advantage to moving too quickly.
The more data, the better. Your engineers can simulate treatment with various media to assess the impact on flare inlet concentrations. And knowing potential impact at the flare is critical; it’s the compliance point where regulators measure sulfur dioxide (SO2) emissions.
SO2 can’t be controlled through combustion, so removing H2S from waste before sending gas to the flare is essential. Sim thinks back to problems he’s investigated for clients who had SO2 sneak up on them, causing failed sulfur dioxide emissions testing.
The proactive measure of identifying problematic gas wells and treating them is key to staying in compliance. And Sim often finds clients using interim solutions as long as they can. He has seen them work well for up to five years but they don’t resolve operators’ long-term issues, which will become more challenging as our waste streams continue to change or as landfills continue to accept more and more C&D materials.
“We solve immediate issues, address the impact of incoming materials several years in advance, and begin planning for the next 20 years. It’s how we determine strategies to minimize emissions and improve efficiencies into the future with consideration to needs as landfilling and recycling evolve.”
“We’re going to investigate thoroughly to pinpoint and understand the cause, but we do take immediate action in the interim. As part of the solution, we’ll develop an informed strategy to prevent issues well into the future,” he says.
For the longer haul, it takes time to get building permits. Coming up with permanent engineering designs and treatments requires a lot of troubleshooting and research. Even once engineers identify a lasting fix, it takes time to manufacture and install larger vessels and other infrastructure.
But they don’t wait for all these pieces to come together to act.
The priority is getting operators in compliance right away or taking down emissions if they are on the verge of noncompliance. As work begins, operators can breathe a little easier knowing they have time to figure out how to allocate resources and funds to implement a more permanent strategy.
“We’ve seen where data we’ve gathered while working on the immediate problem enables our clients to gain insight to make good decisions around rightsizing their infrastructure moving forward,” Sim says.
Watch and study while addressing the immediate problem.
Sim emphasizes that operators should not be surprised or act too quickly when they turn on the gas extraction system and see spikes in H2S concentrations. There is usually an initial spike from a new high H2S producing area at the onset of gas collection. He has seen operators abruptly stop extracting, which can lead to odors or other compliance issues.
“When you put in a treatment system, you can take out the initial surge in H2S to allow time for the concentrations to level out. It’s important to allow that window for initial surges to run their course to understand the problem better. Otherwise, you could over-design your system around a short-term event,” Sim advises.
He points to a real-life scenario: a site that skipped the interim step of starting with a less expensive initial solution. Once they started drawing on the gas, they realized the problem was not as substantial as originally thought, and they didn’t need a multi-million-dollar system in the end.
A balancing act.
“Imagine H2S generation as an expanding balloon; if you pop it, air rushes out fast [akin to when you first pull gas from the ground]. That concentration level scares people. But if you react by shutting off extraction points, your balloon will continue to expand and eventually create odor problems. The goal is to extract the gas and H2S at the rate it is being generated, so it’s a balancing act, where expertise and technology both play key roles,” Sim says.
Early work typically begins by identifying wells that are the highest contributors and concentrating efforts there. It’s a complex process as sites can have fifty to thousands of collection points. Having the historical data and saving the data to watch the trend makes identifying and analyzing specific wells or clusters much more efficient.
Successfully attacking those high offenders requires an understanding of flow and concentrations. After locating the problem area, Sim takes samples using Dräger tubes at strategic points throughout individual wells and headers to identify concentrations. Gas well monitoring and the corresponding flow data will tell you if you’ve taken emissions down sufficiently.
More Resources:
SCSeTools Landfill Data Monitoring and Analysis
Staying Ahead of Odor Management at Solid Waste Facilities
New Chicago office location at 40 Shuman Boulevard, Suite 216, Naperville, IL 60563
SCS Engineers continues expanding its environmental team in its Chicago, Illinois office to meet environmental engineering and consulting needs focusing on waste management and the needs of the electric utilities. Driving demands are industries and municipalities seeking to reduce their environmental footprint while providing essential services and products.
Leading the Chicagoland team, Professional Engineer and Professional Geologist Scott Knoepke. Knoepke serves clients needing remediation and site redevelopment. This includes commercial dry cleaners, retail petroleum sites, and heavy industries such as steel, rail, coal, mining, manufacturing, metal cutting, and plating.
Meet the Crew!
Richard Southorn, PE, PG, with 20 years of experience, joins Knoepke supporting solid waste and electric utility sectors. Southorn began his career in the field performing CQA oversight, environmental monitoring, and soil core/rock core logging at landfill sites. He moved into landfill design and modeling, primarily to support landfill expansion projects. Richard has extensive experience with site layouts, geotechnical stability, stormwater management, and leachate generation analyses.
Brett Miller is a Senior Designer with over 20 years of experience and proficiency in AutoCAD Civil 3D and Maya. Brett is capable of any production drafting and is highly skilled in understanding 3D space. This helps him support designs that fit into site-specific, real-world environments. Brett also creates 3D models and animations that illustrate the benefits of a design to our clients.
Niko Villanueva, PE, joins SCS with eight years of experience. Niko provides engineering and drafting support and is experienced in designing various landfill systems such as stormwater management, leachate and gas control, and foundation analysis. He has also prepared cost estimates and construction bid quantities for various projects and construction quality assurance services at multiple facilities.
Meet Spencer LaBelle, with six years of experience. Spencer provides solutions for stormwater-related projects, including stormwater management system design, permitting, and compliance. He provides a diverse portfolio of clients and industries with stormwater-related services and environmental compliance.
Zack Christ, PE, comes to SCS with 15 years of experience in solid waste and CCR landfill sectors. Zack has experience performing CQA oversight and CQA management of landfill final cover, base liner, and GCCS; environmental monitoring; and logging soil borings. He also has extensive landfill design and CAD experience in developing landfill siting and permitting application projects. Zack’s areas of expertise include geotechnical analyses, stormwater management, leachate management design, GCCS design, and cost estimating.
Recently the state of Wisconsin released its updated 2020-2021 statewide waste characterization study. The study found that the broad organics category, including yard waste and diapers, accounted for about 1.3 million tons. An estimated 924,900 tons of paper, including cardboard, compostable and office paper, comprised about 21 percent of the landfills’ tonnage. That was followed by plastic at about 17 percent or 745,600 tons.
You can read the study, but why do local governments, states, and waste management businesses request these studies? Because waste and landfills are expensive to manage. Diverting waste from landfills cuts greenhouse gases and supplies materials for reuse as new products or compost – a more sustainable system.
Waste characterization information is designed for solid waste planning; however, anyone interested in the characteristics of the solid waste stream may find it useful. Studies can also target specific waste or needs such as construction and demolition waste and business waste generators. A generator means a person, specific location, or business that creates waste.
These studies help start answering questions such as:
States, jurisdictions, citizens, and businesses can use this information as a planning tool to help meet state mandates and their goals to reduce waste and achieve the benefits of sustainable practices. Kudos to Wisconsin, Iowa, and California, several of the many states moving toward more circular waste management!
Recorded September 23, 2021, On-Demand Below
Our SCS Client Webinar focuses on landfill gas maintenance and how Landfill Operators create more efficient operations using their monitoring data. Scott Messier, Site Operations Manager at the Monterey Regional Waste Management District, will join us to describe how he finds efficiencies.
Our panel discusses common operational challenges such as locating new LFG wells, locating the cause of odors or surface emission monitoring hits, determining the cause of LFG migration to probes, identifying obstructions in the header network, getting more gas for a power plant and preventing migration, and identifying elevated temperature conditions.
Approved
The EPA issued a newly approved alternative test method (ALT-143) for compliance with the enhanced monitoring provisions in the National Emission Standards for Hazardous Air Pollutants (NESHAPs) for MSW Landfills (40 CFR 63 Subpart AAAA updated March 26, 2020). The approved alternative method instead of Method 10 allows for direct monitoring of CO at a landfill gas well using a portable gas analyzer. The NESHAP requires weekly monitoring of CO at the landfill gas well if the gas temperature is over 145F and the regulatory agency has approved no higher operating value under the NSPS/EG rules or NESHAPs. The Solid Waste Working Group (SWWG) coordinated with landfill gas meter manufacturers (QED, Elkins Earthworks) to prepare this method.
EIL approved sharing a flow chart and Excel file that can be used for monitoring/documentation purposes when using this approved alternative “field instrument method.” Don’t hesitate to get in touch with your SCS air emissions/compliance expert or contact us at for details.
EPA will post the alternative test method to the Broadly Applicable Approved Alternative Test Methods | US EPA website page. Take note that the hyperlink in EPA’s letter is out of date.
Pending Approval
The Solid Waste Working Group (SWWG) also submitted two alternative methods in lieu of Method 10 to EPA for approval using grab sample (canister, foil bag) and laboratory analysis, one with GC/FID and the other GC/TCD instrumentation. The SWWG coordinated with several national laboratories on the methods. EPA is completing its review of the two proposed methods, anticipating EPA approval before September 27, 2021, the effective date of the enhanced monitoring provisions.
