The National Association of Environmental Professionals (NAEP) will host their 2020 Annual Conference and Training Symposium at the Westin Fort Lauderdale Beach Resort in Fort Lauderdale, Florida, May 18-22, 2020.
Environmental Professionals from across the United States will participate in this conference which will cover a variety of topics, including NEPA, resiliency and adaptation.
Check back for more details as the conference takes shapes and speakers/topics are added to the exciting agenda!
Dr. Iyer is a Staff Professional at SCS focusing on environmental research and engineering in water, wastewater, solid waste, and landfill design. Gomathy is another of our remarkably talented young professionals utilizing her expertise in leachate management and landfill design to support her clients.
We hope you will attend Gomathy’s presentation “Suitability of Un-Composted Grass Clippings and Biosolids as Biocovers for Biological Methane Removal from Landfills,” on Tuesday, February 25 at 8:30 am (Track B: Landfill Covers), at the 2020 Global Waste Management Symposium. Her presentation is based on a technical paper of the same name and co-authored with Melanie Sattler of the University of Texas at Arlington, and Darrin Dillah of SCS Engineers.
Landfill biocovers are widely used to oxidize methane emissions, a known greenhouse gas. The biocovers in use today are typically either fully or partially made of composts. However, the production of compost, although theoretically an aerobic process, also produces potentially substantial quantities of methane, from 3.2 to 362 kg carbon dioxide (CO2)-equivalents per ton of wet waste composted, depending on various factors, for example, the type of waste, and open or enclosed composting technology. This research explored the suitability of using uncomposted grass clippings as a biocover for methane removal from landfills, with the aim of reducing net greenhouse gas emissions.
Physical and chemical characteristics of grass clippings along with other components of yard waste were studied and compared. The use of biosolids and fly ash as potential bulking materials were considered since the physical and chemical characteristics of biosolids and fly ash complemented the grass clippings and biosolids were expected to provide a good inoculum of microbes for the biocover. Batch tests were performed on the grass clippings and combinations of grass, biosolids and fly ash mixtures for aerobic methane removal. Grass clippings were found to have a maximum methane removal rate of 2,121.7 nmol/kg/s, and a combination of grass and biosolids showed a maximum methane removal rate of 4,410.8 nmol/kg/s. Analyzing different proportions of grass, biosolids and fly ash mixtures, it was found that a 70% grass, 21% biosolids and 9% fly ash mixture exhibited the highest methane oxidation of 5,862.5 nmol/kg/s.
Column tests were performed on the grass clippings and on a combination of 70% grass, 21% biosolids and 9% fly ash by introducing a continuous flow of 50% methane and 50% carbon dioxide at the bottom of the column reactor containing 2 feet of biocover material. The column reactors with grass clippings showed a methane removal of 90-100% within the first 10 days, and the reactors with the combination of grass, biosolids and fly ash showed a methane removal of 90-100% within first 3 days. Biocover performance indexes were calculated based on the performance of each biocover. The biocover performance index for grass was found to be 20.8 µg/g/hr and that for the combination of 70% grass, 21% biosolids and 9% fly ash was found to be 43.3 µg/g/hr.
Representative samples were taken from the column reactors to analyze for the presence of methanotrophs involved in the methane removal process. A PCR (Polymerase Chain Reaction) analysis was performed on these samples with A189 (forward) and A682 (reverse) primers. The evidence of pMMO PCR amplification products was seen in all column reactor samples, indicating the presence of the pMMO gene, which is found in methanotrophs and hence confirmed the presence of methanotrophs. A BLAST (Basic Local Alignment Search Tool) was performed on the sequence obtained from the PCR analysis confirmed methalocystis and type 2 methanotrophs. Figure 1 shows the gel picture of the PCR analysis of the column reactor samples. #1
LEAF testing was conducted to analyze the leachability of fly ash in the biocover. It was seen that silver, arsenic, cadmium, chromium and thallium exceeded the permissible level in drinking water. Hence, it was concluded that the grass clippings by itself or a combination of grass and biosolids can be used as a biocover for biological methane removal.
Global Waste Management Symposium 2020
February 23 @ 8:00 am – February 26 @ 5:00 pm
2020 GWMS Information
Article published in the January 2020 edition of Waste Advantage Magazine.
At the Federal level, GHG emission reporting has become part of the standard regulatory requirements; however, on the west coast, GHG programs continue to develop and evolve from reporting to reduction programs beyond federal requirements. Solid waste facilities can be impacted by all of these reporting mechanisms directly as a landfill located in the state in question, opting in for C&T as part of the LCFS in California, or in limbo, as the courts work out the legality of Washington’s Clean Air Act. More stringent federal GHG requirements are unlikely with the current administration, however, that could change with the 2020 election. In general, GHG rules and legislation keep developing and updating to account for and reduce GHG emissions.
Cassandra Drotman Farrant is Project Manager with SCS Engineers. She has nine years of experience in environmental consulting, specializing in environmental assessment and greenhouse gas (GHG) verification. Cassandra has participated in many GHG verification projects throughout the U.S. and has completed approximately 70 Phase I Environmental Assessments (ESAs) in California, Oregon, and Washington. Phase I projects included research and review of geologic and hydrogeologic conditions at project sites and in the surrounding areas and evaluating the potential for soil and groundwater contamination from on and offsite sources. Cassandra has completed emissions estimates and inventories and has prepared numerous permit-to-construct/operate permit applications. She prepares compliance reports, which includes reviewing and maintaining records and regulatory deadlines.
SCS Engineers provides engineering, consulting, operations and monitoring services to report and reduce greenhouse gas emissions. Select a service category to learn more.
The International Solid Waste Association (ISWA) has determined that uncontrolled dumpsites hold 40% of the world’s waste and that the world’s 50 biggest dumpsites (identified through a voluntarily survey conducted by D-Waste in 2014) directly affect the daily lives of 64 million people, equivalent to the population of France.
The ISWA reports (2014, 2015a, 2015b, 2016) showcase how eliminating dumpsites is an urgent issue, affecting local, regional, and even global health and the environment. Important findings indicate that 38 out of the 50 biggest dumpsites directly impact marine and coastal areas and can become sources of disease outbreaks and the release of wastes (particularly durable plastics) to waterways and the oceans.
Studies suggest that non-engineered dumps and uncontrolled landfills are the third largest source of global anthropogenic methane, a greenhouse gas about 25 times more potent than carbon dioxide (CO2), accelerating climate change. It is estimated that open dumps emit the equivalent of more than 20 million metric tonnes [tons] of CO2 per year. Without any action, it is projected that existing open dumps will account for 10% of global greenhouse gas emissions by 2025.
If open dumps instead were replaced by engineered landfills with state-of-the-art landfill gas collection and destruction systems, it would be like removing five million cars from the planet.
In 2018, ISWA’s Working Group on Landfill (WGL) developed a Task Force on Closing Dumpsites (TFCD) and presented its dump closure initiative as one of its flagship projects for the future at the United Nations (UN) Conference on Housing and Sustainable Urban Development – Habitat III.
Please read this important ISWA Editorial by James Law and David Ross on this significant issue. The editorial contains a link to the full article available on open access through ISWA’s Journal, Waste Management & Research here.
SCS Engineers brochure – Closing Dumpsites is also available.
This article discusses global air quality and how the collaboration between policy-makers and the scientific community can have a continued positive impact on air quality in the U.S. This collaboration has been the primary cause for the improvements observed in air quality over the past few decades.
U.S. Environmental Protection Agency (EPA) programs, such as the New Source Performance Standards (NSPS), New Source Review, and Maximum Achievable Control Technology standards, have all had a significant impact on improving air quality by lowering the ambient concentrations of NOX, VOC, CO, SOX, and PM.
Some areas, such as southern California, have committed to working toward electrifying the transportation network, implementing more stringent standards on diesel fuel sulfur content, and encouraging heavier utilization of public transportation.
Author: SCS Engineers’ Ryan Christman, M.S., is an air quality engineer and environmental management information systems specialist with experience in the oil and gas industry and the solid waste industry. He is just one of SCS’s outstanding Young Professionals.
“This program directly supports the county’s Roadmap to a Sustainable Waste Management Future by helping businesses to implement recycling programs,” says Leonard. “And not only recycling but waste reduction, as well, all of which, of course, contribute to reducing greenhouse gas emissions, resource management and sustainable materials management.”
…and as waste settles, it can have an effect on equipment,” according to Pat Sullivan of SCS Engineers in this ClimateWire article. As the U.S. EPA focuses on pushing landfill owners into cutting down on methane emissions some worry that a combination of tightening regulations and poor cost analysis might put some smaller landfills out of business.
LANDFILL EMISSIONS: Going to the dump? You might make electricity
Kavya Balaraman, E&E reporter
Reprinted from ClimateWire with permission from E&E Publishing, LLC. Copyright 2016.
SCS periodically prepares technical bulletins to highlight items of interest to our clients and friends. These are published on our website. This SCS Technical Bulletin addresses:
On July 11, 2016, multiple organizations representing the full value chain of cellulosic waste feedstock conversion to transportation fuel sent a letter to Gina McCarthy, Administrator of the U.S. Environmental Protection Agency (EPA). The letter supporting the Renewable Fuel Standard Program: Standards for 2017 and Biomass-Based Diesel Volume for 2018 (Proposed Rule) noted that additional information and factors need to be considered.