liquids management

Wisconsin Integrated Resource Management Conference (WIRMC), Green Bay

January 5, 2023

SCS Engineers is a Silver Sponsor of the Wisconsin Integrated Resource Management Conference (WIRMC) to be held February 22-24 at the Hyatt Regency in Green Bay.

The conference will feature numerous networking opportunities, exhibitors, field trips, and several tracks exploring the latest solid waste management trends and practices.

The following SCS professionals will be presenting at the conference:

Vice President Betsy Powers is co-presenting in “Getting Up to Speed: Effectively Onboarding People for Success”
with Analiese Smith of Waukesha County and Karin Sieg of Recycling Connections
[Track Session II, Thursday, February 23 at 2:30]

Abstract: Solid waste organizations are looking to hire, and the waste business doesn’t have the glamor some other companies can offer. With a tight talent pool available, organizations with good onboarding programs can help attract good talent by highlighting the organization’s culture, reduce the time for a new employee to become a productive employee, boost employee engagement and help build a stronger company culture. We don’t often talk about topics like this, but building and maintaining a strong work force in our field is important. So let’s start talking about it!

Betsy Powers will also co-present on “How One MN Waste Processing Facility is Tackling 75% Diversion”
with Nate Klett of Foth
[Track Session V, Friday, February 24 at 10:30 am]

Abstract: Ramsey and Washington Counties recognize that there is often value to the items that people put in the trash. R&E sees the waste stream as a resource stream. This resulted in the 2016 purchase of the Recycling & Energy Center (R&E Center), located in Newport, Minnesota. All trash generated by individuals and businesses in the two counties is delivered to the R&E Center, where R&E works to recover value. The R&E Center is permitted to process 500,000 tons of trash per year. Trash is processed to recover recyclable metals and make fuel for producing electricity. In 2019, nearly 90% of the waste from the two counties was diverted from landfill because of the processing that occurs at the R&E Center. After researching and evaluating options to recover recyclables in the trash, R&E has targeted residential food scraps and remaining recyclables in trash as the next resources to recover from the mixed waste stream. The R&E Center is adding equipment to recover residential organics placed in durable compostable bags that are comingled with trash. Additional equipment upgrades will recover high-value recyclables such as metals, plastics and cardboard. Research is also under way to partner with private industry to utilize anaerobic digestion to recover value from the organics recovered at the R&E Center. We’ll discuss the research and reconnaissance as well as the design and installation of these systems and touch on the technologies that are being considered for recovering additional value from the byproducts.

 

The Wisconsin Integrated Resource Management Conference is the #1 place to market your business to Wisconsin solid waste and recycling professionals at the Exhibit Hall.

The Wisconsin Integrated Resource Management Conference is jointly hosted by the Associated Recyclers of Wisconsin (AROW), the Solid Waste Association of North America (SWANA) – Badger Chapter, the Wisconsin Counties Solid Waste Managers Association (WCSWMA) since 2000, and Recycling Connections, allowing professionals from all aspects of the solid waste & recycling industry to collaborate and learn from one another.

Click for more conference details and registration information

 

 

 

Posted by Laura Dorn at 7:03 pm

PFAS Treatment Options and Regulatory Movement

May 25, 2022

SCS Engineers Environmental Consulting and Contracting

 

Regulatory movement around PFAS is picking up; this year and next could be monumental around managing these toxic compounds in landfills and leachate. Operators should look out for proposed U.S. Environmental Protection Agency (EPA) rules in 2022 and final rules in 2023. Most notably, two PFAS categories, PFOA and PFOS, could be classified as hazardous wastes under the Resource Conservation and Recovery Act (RCRA) and the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), aka Superfund. Also, expect rules on monitoring and limiting PFAS in drinking water.

Amidst this regulatory activity, PFAS treatment research advances, which will be critical to landfill operators when they are charged with managing this very challenging stream. With existing options, it’s near impossible to destroy these “forever chemicals,” known for their carbon-fluorine bond, considered one of the strongest in nature.

SCS Engineers’ Gomathy Radhakrishna Iyer advises operators on what to look for to brace for regulatory change and advises them on their best defense—the treatment piece. She explains current options and potential technology breakthroughs on the horizon.

“On the legislative front, standardized guidance might not happen overnight. There’s much to learn, as leachate is not the same, including as it pertains to PFAS. Concentrations and compounds vary. So, EPA is gathering data and knowledge to inform policy and mitigation options moving forward,” Iyer says.

Today’s focus entails developing and validating methods to detect and measure PFAS in the environment. The EPA is evaluating technologies to reduce it and is trying to understand better the fate and transport of PFAS in landfills (including landfill gas, leachate, and waste).

While PFAS concentrations in leachate sent to publicly owned treatment plants (POTW) are unknown, the EPA 2023 rule aims to fill in the missing pieces. What is learned and subsequent decisions will be critical to landfill operators who depend on POTWs as a final destination for leachate and at a time when POTWs meet stringent guidelines on what they can accept. The EPA’s focus will begin with guidance on monitoring and reporting figures, including a list of PFAS to watch for in 2022.

In the meantime, the agency published interim guidance on destroying and disposing of PFAS, which it plans to update in fall 2023. The interim guidance identifies the information gap with regard to PFAS testing and monitoring, reiterating the need for further research to address the FY20 National Defense Authorization Act NDAA requirements. Operators can also look to SWANA treatment guidelines to help prepare for new rules.

Get ahead of the game by doing your homework on treatments, Iyer advises. POTWs have discharge limits, and once PFAS in leachate is weighed in with the existing constituent limits on permits, ensuring a disposal destination will call for proactive measures.

The discussion on treatments will be important. Iyer advises on staying up with expectations that may be in the pipeline, beginning by focusing on today’s commercially available options:

  • Biological processes (which leverage microbes that attach to leachate and remove PFAS). These processes include:
    • Anaerobic digester
    • Membrane bioreactor
  • Physical-chemical processes to include:
    • Ion exchange, leachate passes through resins in a vessel that binds PFAS.
    • Reverse osmosis (RO), leachate flows through a membrane; PFAS is separated and collected in a solution.
  • Granular activated carbon (GAC), PFAS passes through a vessel and adsorbs into the carbon; then, the pretreated leachate passes through.

Comparing these methods, Iyer says, “Biological treatments work better simply as a pretreatment method, removing PFAS to some extent. Their performance may also only apply to non-biodegradable organic matter. Considering these limitations, the alternative of physical-chemical treatments is most often recommended by industry experts; they appear to be more effective as supported by data,” Iyer says.

Her preference is RO, the membrane-enabled separation process, which many treatment plants already use, or are considering, to remediate other constituents. “Because we know RO to be effective with other contaminants and PFAS, I think it’s a great gainer, especially if plants already use this method to treat leachate for other contaminants successfully,” she says.

RO requires relatively little operational expertise, while other physical-chemical methods, such as GAC and ion exchange, require some chemistry knowledge.

“With granular activated carbon and ion exchange, resins attach to contaminants in leachate. These approaches require pretreatment for organics removal, process understanding, and operator involvement. Conversely, with RO, you learn a fairly straightforward process and move through the steps,” she says.

But while physical-chemical treatments are the best readily available options today, each has limitations. RO leaves a residue requiring further treatment; then, the material is typically recirculated in landfills as a slurry or hauled to a POTW, meaning there is no guarantee they will not need to be addressed later. Other methods, such as GAC, are more energy-intensive and have limited sorbent capacity. Ion exchange, in particular, has difficulty removing short-chain PFAS, which persist in the environment.

When the time comes that PFAS have stringent discharge limit requirements, no one of these technologies may work as a standalone, so the search is on for more robust systems.

Several new treatments are under research; unlike their predecessors, they appear to break the chemical bond. 

  • Plasma treatment. An electromagnetic field is applied to gas to produce charged electron bubbles of gas in water, which remove PFAS.
  • Adsorption. Similar to GAC, this treatment entails adding chemicals that effectively adsorb PFAS on the surface.
  • Photocatalytic reaction. Photocatalysts are strong oxidants that help remove contaminants in the presence of ultraviolet (UV) rays.
  • PFAS are thermally destructed, resulting in the breakdown of most compounds and disintegration of many of them.

Iyer shares her take on each option:

“I’m especially interested in seeing how plasma treatment works in the real world versus the lab. The building costs can be higher, and leveraging electricity to break the bond is expensive. But the maintenance should be easy and relatively inexpensive compared to other technologies. It will be interesting to see how economical it would be for landfills over the long run.”

There is more to learn about each of these new technologies. Researchers are working to identify the adsorbents that best suit PFAS compound removal, whether short or long chains. With photocatalytic reaction, a research direction is exploring combining UV rays, a catalyst, and an oxidant to degrade PFAS.

“We know that the absorption options and photocatalytic concepts work well on strong contaminants,” Iyer says. She moves on to her thoughts on thermal treatment. She wants to know more about this particular option before weighing in. “I’m not sure how feasible this method will be for the operators. PFAS get destroyed at a temperature greater than 1,000 degrees Celsius. But for high quantities of leachate, this option could be expensive.”

Most EPA-funded research is based on these developing treatment processes. But there is plenty to evaluate to identify the best solutions in a given scenario. With that understanding, the agency is trying to understand the types and volumes of PFAS generated, how they change or degrade as they enter landfills, and where they originate. EPA is building a database to track this information to consider key characteristics of individual PFAS to help guide forthcoming guidance on treatments.

In the meantime, Iyer advises operators to pay close attention to evolving developments and communications from EPA.

 

We recently saw the memorandum from EPA on addressing PFAS discharges in EPA-issued NPDES permits. We will look for guidance to the state permitting authorities to address PFAS in NPDES permits soon and more information from the EPA’s roadmap.

At SCS, we use our time to learn about technologies, including what’s still under investigation and explore what seems to work. In addition, watch for guidance documents, not just from EPA but from research organizations such as EREF and universities. Do your due diligence and keep your eyes and ears open for EPA and your state regulatory authority announcements. Staying informed is the best strategy for landfill operators at this point.

 

Liquids and wastewater management resources.

 

 

 

 

 

Posted by Diane Samuels at 11:47 am

Biodiesel & Renewable Diesel Summit, Minneapolis

May 17, 2022

Meet SCS Engineers professionals, including Monte Markley, Nathan Hamm, and Gary Vancil, who are attending the 3rd annual Biodiesel & Renewable Diesel Summit in Minneapolis, June 13-15, 2022.

The summit will also feature a Carbon Capture & Storage Summit preconference on June 13, as well as an added focus on liquids management.

The Biodiesel & Renewable Diesel Summit is a forum designed for biodiesel and renewable diesel producers to learn about cutting-edge process technologies, new techniques and equipment to optimize existing production, and efficiencies to save money while increasing throughput and fuel quality. Produced by Biodiesel Magazine, this world-class event features premium content from technology providers, equipment vendors, consultants, engineers and producers to advance discussion and foster an environment of collaboration and networking through engaging presentations, fruitful discussion and compelling exhibitions with one purpose, to further the biomass-based diesel sector beyond its current limitations. Co-located with the International Fuel Ethanol Workshop & Expo and the National Biomass Conference & Expo, the Biodiesel & Renewable Diesel Summit conveniently harnesses the full potential of the integrated biofuels industries while providing laser-like focus on processing methods that are sure to yield tangible advantages to biomass-based diesel producers.

Click for more details and registration information

 

 

Posted by Laura Dorn at 11:26 am

NWRA and SWANA Urge Congress to Refine CERCLA – PFAS Language

May 12, 2022

Important 2022 Regulatory Announcement from SCS Engineers
CERCLA – PFAS Announcement

In a letter to Congress, SWANA and NWRA associations request that regulation under the Comprehensive Environmental Response,Compensation, and Liability Act (CERCLA) for addressing per- and polyfluoroalkyl substances (PFAS) contamination assign environmental cleanup liability to the industries that created the pollution in the first place.  Both associations note that MSW landfills and solid waste managment, an essential public service do not manufacture nor use PFAS. The industry, and ultimately the general public should therefore not be burdened with CERCLA liability and costs associated with mitigating PFAS from water and wastewater.

NWRA and SWANA CERCLA – PFAS letter.

 

May 10, 2022

Re: Relief for Municipal Solid Waste Landfills from CERCLA Liability for PFAS

Dear Chairman Carper, Ranking Member Capito, Chairman DeFazio, Ranking Member Graves, Chairman Pallone, and Ranking Member McMorris Rodgers:

The municipal solid waste (MSW) management sector strongly supports the goal of addressing per- and polyfluoroalkyl substances (PFAS) contamination and holding accountable manufacturers and heavy users of these compounds. We are concerned, however, that regulation under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) instead would assign environmental cleanup liability to essential public services and their customers. We therefore request that Congress provide MSW landfills and other passive receivers with a narrow exemption from liability if certain PFAS are designated as hazardous substances under CERCLA. Doing so would keep CERCLA liability on the industries that created the pollution in the first place.

Context

• Landfills neither manufacture nor use PFAS; instead, they receive discarded materials containing PFAS that are ubiquitous in residential and commercial waste streams. MSW landfills and the communities they serve should not be held financially liable under CERCLA for PFAS contamination, as landfills are part of the long-term solution to managing these compounds.
• Landfills are essential public services that are subject to extensive federal, state, and local environmental, health, and safety requirements. Further, MSW landfills are important to managing and limiting PFAS in the environment, as recognized by the Environmental Protection Agency (EPA) in its December 2020 draft Interim Guidance on the Destruction and Disposal of [PFAS] and Materials Containing [PFAS].
Just as certain airports are required by law to use firefighting foam containing PFAS, permitting authorities often require landfills to accept waste streams containing PFAS.
• Most landfills rely on wastewater treatment facilities for leachate management. Wastewater and drinking water facilities increasingly rely on landfills for biosolids management and disposal of PFAS-laden filters. Efforts to address PFAS at MSW landfills and drinking water and wastewater facilities must avoid disrupting this interdependence among essential public services to communities.
• Landfill leachate typically represents a minor proportion of the total quantity of PFAS received at wastewater treatment facilities from all sources. PFAS manufacturers or users, by comparison, contribute PFAS at levels that can be orders of magnitude higher than landfills.

Significant Economic Impacts

• Removing PFAS from landfill leachate requires advanced treatment techniques which are prohibitively expensive. Estimated capital costs to implement leachate pretreatment at a moderate-sized landfill to the extent necessary to significantly reduce PFAS range from $2 million to $7 million, with nationwide costs totaling $966 million to $6.279 billion per year for the solid waste sector. Trace concentrations of PFAS nevertheless would remain in leachate following pretreatment, exposing landfills to CERCLA liability.
• Absent relief from CERCLA liability, manufacturers and heavy users of PFAS compounds will bring claims for contribution against landfills and other passive receivers, generating significant litigation costs. EPA’s exercise of enforcement discretion will not insulate landfills from this litigation.
• These costs will be passed along to communities, water and wastewater treatment facilities, and biosolids management, all of which rely on the services of MSW landfills.

Broad Unintended Consequences

CERCLA regulation will impel landfills to restrict inbound wastes and/or increase disposal costs for media with elevated levels of PFAS, including filters, biosolids, and impacted soils at Department of Defense facilities. The mere prospect of regulation in this area is already disrupting the interdependence of the drinking water, wastewater, and solid waste sectors.
• Food waste compost may contain PFAS due to contact with PFAS-lined packaging materials. As a result, a CERCLA designation could result in communities diverting food waste from organics recycling programs, hindering federal, state, and local climate and waste reduction goals.
• Cost increases likely will have a significant disproportionate impact on low-income households that rely on the affordability of services that the solid waste sector provides.

Recommendation

Although our sector is simultaneously pursuing “no action assurance” from EPA, the agency historically has been very hesitant to provide this relief given its policy that assurances should be given only “in extremely unusual cases.” As such, and acknowledging that EPA may have limited authority to act on our request, we recommend providing the following narrow exemption from CERCLA liability that affords relief to landfills and other passive receivers of PFAS1:

(a) IN GENERAL.—No publicly owned or operated community water system (as defined at 42 U.S.C. 300f), publicly owned treatment works (as defined at 33 U.S.C. 1292), or municipal solid waste landfill (as defined at 40 C.F.R. 258.2) shall be liable under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (42 U.S.C. 9601 et seq.) for the costs of responding to, or damages resulting from, a release to the environment of a perfluoroalkyl or polyfluoroalkyl substance designated as a hazardous substance under section 102(a) of such Act that resulted from the discharge of effluent, the disposal or management of biosolids, the disposal of filtration media resin, or the discharge of leachate where such actions are in compliance with Federal or State law and all applicable permits.

(b) EXCEPTION.—Subsection (a) shall not apply with respect to any discharge described in such subsection that results from any gross negligence, willful misconduct, or noncompliance with any Federal or State law or permit governing the discharge of effluent, disposal or management of biosolids, disposal of filtration media resin, or waste disposal.

Thank you for your consideration of our request, and we look forward to continuing to partner with the federal government to ensure the safe and effective management of waste streams containing PFAS.

Sincerely,
National Waste & Recycling Association
Solid Waste Association of North America

cc: Senate EPW Committee Members
House T&I and E&C Committee Members

_______________________________________

1 The exemption would not extend to underlying soil and groundwater contamination from a MSW landfill or to facilities other than MSW landfills that accept waste streams with elevated concentrations of PFAS.

 

Posted by Diane Samuels at 12:22 pm

Leachate Management and Disposal Forum On-Demand!

January 3, 2022

If you missed the latest SCS Engineers client forum, not to worry, we’ve recorded it for you.

 

Clients, regulators, and environmental engineers participated in the SCS December forum. Samuel Cooke, PE/chemist; Nathan Hamm, PE/landfill liquids engineer; and Monte Markley, PG/deep disposal well expert, deliver valuable information and insights in this 70-minute session. They answer your questions about how leachate treatment and disposal preplanning can uncover efficiencies and open up options for managing landfill leachate and PFAS.

You work hard to stay on top of a diverse and complex mix of leachate contaminants — heavy metals, ammonia, and biochemical oxygen demand, among them. Lately, we have even more to think about, including keeping concentrations of these contaminants within the wastewater treatment plant’s tightening discharge limits and addressing compliance pressures as the list of constituents on regulators’ radar grows.

Exploring leachate treatment options to find the most fitting and cost-effective one takes vetting by a team of experts and field experience. For SCS’s December discussion and Q&A, our panelists brought their decades of expertise helping landfills, manufacturers, and waste facilities find more options and the most sustainable solutions and practices.

 

Click here to watch the video.

 

Additional Resources for Planning, Managing, Monitoring, and Treatment 

Monitoring leachate, pumps, pressures, and more:

  • Managing liquids – Changing waste streams and more rainfall in certain areas of the country complicates liquids management. SCS 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.
  • From maps to interfacing data forms to the next level X-ray vision. We’re doing 3D well visualizations, which give a kind of Superman X-ray vision subsurface. You are literally looking beneath to the well to get good intel,” Stephens says. Wellfield visualization allows you to see the subsurface field and well conditions, including pumps.

Scientific & Technical Studies/Resources

 

 

 

 

 

 

 

Posted by Diane Samuels at 6:00 am

SCS’s Michael Simms Appointed to the Louisiana Board of Professional Geoscientists

December 3, 2021

Michael Simms – Appointed by the Governor to the Louisiana Board of Professional Geoscientists

The Louisiana Board of Professional Geoscientists oversees the approvals of hydrogeologists and like scientific professionals in the state. This is quite an honor for Mike, a hydrogeologist with more than 30 years of experience. He learned of the appointment earlier this month and just had his first meeting.

Hydrogeologists are attempting to solve some of the big questions facing the world today, including sustainable water supply, food and energy production; environmental protection; and coping with climate change. They work closely with a wide range of industries to protect groundwater and much, much more.

Congratulations, Mike!

 

 

 

 

 

 

Posted by Diane Samuels at 6:00 am

Leachate Treatment and Disposal Preplanning: Preparing and Uncovering Options for Landfills

November 19, 2021

On December 16, SCS Engineers presented another free technical discussion and QA about how preplanning helps you prepare and uncover leachate treatment and disposal options at landfills.

If you missed it, click here for the recording that includes the Q&A!

The waste industry works hard to stay on top of a diverse and complex mix of leachate contaminants — heavy metals, ammonia, and biochemical oxygen demand, among them. Lately, we have even more to think about, including keeping concentrations of these contaminants within the wastewater treatment plant’s tightening discharge limits and addressing compliance pressures as the list of constituents on regulators’ radar grows.

Exploring leachate treatment options to find the most fitting and cost-effective one takes vetting. Our panelists for December’s discussion and Q&A: Leachate Treatment and Disposal Preplanning: Preparing and Uncovering Options for Landfills have decades of expertise helping landfills, manufacturers, and waste facilities find the most sustainable solutions.

 

 

Watch this month’s forum about leachate treatment and disposal preplanning to inform your alternatives analysis in order to achieve the best results, including:

  • Positioning your facility or landfill to be as independent as possible using proven treatment technology
  • Compiling crucial information around current leachate generation and future projections with site-specific characteristics of the liquids to reduce risk
  • Vetting multiple leachate treatment systems and disposal options, sizing up each one to properly address your sites’ individual needs
  • Identify an interim solution if necessary.

This SCS forum is suitable for waste management, landfill, and compliance staff, managers, and engineers of all levels.

Sessions are interactive with Q&A throughout, and as always, these are non-commercial. Your privacy is protected.

 

 

 

 

 

 

Posted by Diane Samuels at 10:39 am

SWANA ARF Report on PFAS Management and Treatment Options for Landfill Leachate

November 15, 2021

 

SWANA is optimistic regarding the positive role modern MSW landfills can play in managing solid waste – such as carpeting and clothing – containing PFAS. By disposing of these products in landfills and effectively treating landfill leachate for PFAS removal, the solid waste industry can provide society with an effective and proven method of managing PFAS wastes.

In support of members, the SWANA Applied Research Foundation (ARF) has issued a report summarizing and analyzing management options and treatment technologies that can address PFAS chemicals contained in landfill leachate on November 10, 2021. PFAS Management and Treatment Options for Landfill Leachate is available to SWANA ARF subscribers.

The research findings presented in the resulting report are based on a comprehensive review of the literature and an analysis of the commercially-available PFAS treatment systems and other management options for landfill leachate.

The new report serves as a companion report to one published by the ARF in June 2021 on PFAS Fate and Transport in WTE Facilities, available in SWANA’s Reports List.

 

 

 

 

Posted by Diane Samuels at 6:08 am

Maintaining Gas Extraction System Pumps Saves Time and Money | SCS Field Services

September 7, 2021

SCSeTools LFG data to create operational efficiencies for landfill operators
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.

 

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.

 

Wellfield liquid levels and detail at a glance. Using a landfill’s collected data, narrow down the entire well field’s pumps to determine what needs investigation and where it is using GIS. Supervisors can check the overall monitoring status, select a well pump not performing to see the details, then assign technicians exactly where most needed.

 

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.”

 

More Resources

 

Posted by Diane Samuels at 6:00 am

Taming the Elephant in the Room – A Landfill’s Story of Leachate Treatment and Disposal

August 23, 2021

leachate and PFAS filtration SCS Engineers

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