In implementing the EPA’s federal requirements for Coal Ash Residual – CCR sites, the Texas Commission on Environmental Quality’s CCR program needs to be at least as protective as the requirements of the self-implementing federal CCR rules. The TCEQ also is charged with making the Texas CCR program consistent with other TCEQ regulatory programs. As such, the TCEQ incorporated various provisions of state permitting programs and procedures into Chapter 352.
Whereas many of the EPA’s federal requirements are adopted directly by reference to the federal CCR rules (40 Code of Federal Regulations, as amended through April 17, 2015, issue of the Federal Register (80 FR 21301)), other requirements were tailored and, or expanded to be consistent with TCEQ programs. Following are select examples correlating the EPA and TCEQ requirements:
There were also five provisions of the federal CCR regulations that the TCEQ did not include in its permit program. These are addressed in EPA’S announcement regarding the TCEQ’s application requesting partial approval of their CCR state permit program. See https://www.epa.gov/coalash/us-state-texas-coal-combustion-residuals-ccr-permit-program
EPA is hosting a free workshop in January on landfill monitoring and emissions. The workshops are scheduled twice, over half-day sessions. These sessions will include presentations highlighting the latest technological developments for monitoring and measuring landfill gas emissions.
Dates and Times: Register once for both sessions.
If you have any questions, please contact Shannon Banner at or John Evans at .
As large tracts of geographically desirable vacant land become scarcer, residential and commercial property developers are increasingly turning to old landfills or former dumps. However, such redevelopment is complex and rife with uncertainties. When compared to greenfield development, the land acquisition costs are lower. Still, any savings are typically offset by greater environmental and infrastructure costs associated with the foundation, landfill gas management, stormwater management, groundwater impacts, meeting closure requirements, and multiple regulatory agency coordination. Therefore, it is important to maximize the developable area while providing engineering solutions to make the project economically feasible. In this blog, we identify some options to reuse challenging sites and lessons learned to contribute to successful redevelopment projects.
Deep Dynamic Compaction
Old landfills or dumps present some unique soil stability challenges. Deep dynamic compaction (DDC) is a ground stabilization technique that has gained popularity in recent years to improve subsurface soil conditions. DDC involves dropping 6 to 30-ton weights from a height between 30 and 75 feet to achieve the desired soil compaction. DDC can effectively apply to a range of subsurface materials, including former C&D debris or municipal solid waste dumps.
DDC provides a stable foundation for future development, minimizes differential settlement while leaving the landfill waste in place, and eliminates the costs associated with removing, transporting, and disposing of buried waste, costing millions of dollars. For simplicity’s sake, let’s consider a 1-acre old landfill or a dumpsite with an average of 15 feet of waste. If excavating the waste and replacing it with clean fill, the disposal fee costs for the excavated waste alone could exceed $400,000. Alternatively, DDC costs range from $1.50 to $2.00 per square foot or $65,000 to $87,120 per acre, excluding mobilization, which costs around $30,000.
Gas Mitigation Systems
Constructing buildings on top of dynamically compacted areas generally requires a combustible gas barrier layer below the building foundation to manage subsurface combustible gases (typically methane). The barrier is required because the waste remains in place. In its simplified form, gas mitigation systems include:
These gas mitigation systems can be either a passive or an active system with a blower. The cost of such systems varies depending on the size of the building, location, and type of liner system used. Typical capital costs for passive systems are in the range of $7 to $9 per square foot for the spray-applied liner and $3 to $4 per square foot for the HDPE liner. For an active system using blowers, add $3 to $4 per square foot. The designer configures a system from these options to address the client’s risk preference and considering future tenant preferences.
Using innovative approaches, impaired lands are increasingly attractive to developers. Beyond the cost-saving benefits to developers realized through DDC and an appropriate gas mitigation system, such projects also create local jobs, increase the tax base, and protect public health and the environment.
About the Authors:
Somshekhar Kundral – Mr. Kundralis, PE, is a Senior Project Manager with over 12 years of broad and diverse environmental engineering experience that includes projects in landfill redevelopment, landfill gas management system design, site assessment, groundwater remediation system design, stormwater management, and injection well system construction. Som is experienced with site permitting, compliance reporting and construction administration services, and remediation systems’ operation and management.
Maura Dougherty is joining SCS’s Southwest Business Unit as a Senior Project Manager in the solid waste engineering practice. Dougherty will execute engineering design, operations support, and construction quality assurance projects. She is responsible for project management, client service, business development, technical leadership, and overseeing professional staff teams. Dougherty reports to Vice President and Southwest Business Unit Director of Engineering, Vidhya Viswanathan, P.E., from SCS’s Pleasanton office.
“Maura is a senior professional with proven extensive success in solid waste engineering, construction, and construction quality assurance solutions,” said Viswanathan. “Her experience managing landfill and landfill gas collection and control system engineering and construction projects strengthen our efforts to support our solid waste and recycling clients.”
Dougherty is a registered Professional Engineer in California, Oregon, Washington, and Hawaii. She brings over 20 years of experience overseeing landfill engineering and construction projects, coordinating with regulatory staff, conducting design and technical reviews, and supporting construction work. Dougherty earned her B.S.E. in civil engineering at the University of Princeton and her M.S. in environmental engineering from U.C. Berkeley.
On November 30, 2020, the Environmental Protection Agency announced it is aggressively addressing per- and polyfluoroalkyl substances (PFAS) in the environment. The agency announced two steps that it states would help ensure that federally enforceable wastewater monitoring for PFAS can begin as soon as validated analytical methods are finalized.
First, EPA issued a memorandum detailing an interim National Pollutant Discharge Elimination System (NPDES) permitting strategy for addressing PFAS in EPA-issued wastewater permits.
EPA’s interim NPDES permitting strategy for PFAS advises EPA permit writers to consider including PFAS monitoring at facilities where these chemicals are expected to be present in wastewater discharges, including from municipal separate storm sewer systems and industrial stormwater permits. The PFAS that could be considered for monitoring will have validated EPA analytical methods for wastewater testing. The agency anticipates being available on a phased-in schedule as multi-lab validated wastewater analytical methods are finalized. The agency’s interim strategy encourages the use of best management practices where appropriate to control or abate the discharge of PFAS and includes recommendations to facilitate information sharing to foster adoption of best practices across states and localities.
Second, EPA released information on progress in developing new analytical methods to test for PFAS compounds in wastewater and other environmental media.
In coordination with the interim NPDES permitting strategy, EPA is developing analytical methods in collaboration with the U.S. Department of Defense to test for PFAS in wastewater and other environmental media, such as soils. The agency is releasing a list of 40 PFAS chemicals that are the subject of analytical method development. This method would be in addition to Method 533 and Method 537.1 that are already approved and can measure 29 PFAS chemicals in drinking water. EPA anticipates that multi-lab validated testing for PFAS will be finalized in 2021. For more information on testing method validation, see https://www.epa.gov/cwa-methods.
EPA continues to expand its PFAS Action Plan to protect the environment and human health. To date, it has assisted more than 30 states in helping address PFAS, and the agency is continuing to build on this support. Across the nation, the EPA has addressed PFAS using a variety of enforcement tools under SDWA, TSCA, RCRA, and CERCLA (where appropriate), and will continue to protect public health and the environment.
The agency is also validating analytical methods for surface water, groundwater, wastewater, soils, sediments, and biosolids; developing new methods to test for PFAS in air and emissions; and improving laboratory methods to discover unknown PFAS. EPA is developing exposure models to understand how PFAS moves through the environment to impact people and ecosystems.
Related Information
This blog references information issued from the US EPA, Office of Public Engagement.
SCS Engineers’ newest environmental technology application is for use at solid waste facilities and landfills. These sites require specific monitoring and analyses of groundwater and liquids, landfill gas – LFG, and surface emissions critical to facility infrastructure and the environment.
“We work side-by-side with our clients at hundreds of facilities nationwide. SCS MobileTools® supports operating decisions, whether our client is managing one site or hundreds,” states Pete Carrico, senior vice president and assistant director of SCS Field Services.” The App’s interface gives clients quick access to information that drives critical operating decisions and provides data for corporate directives and landfill gas OM&M programs for regional or national operations.
SCS MobileTools® is the iOS and Android mobile interface for the SCSeTools® platform. Access to data to make informed decisions is especially valuable when technicians are in the field, or operators are working remotely. Landfill and solid waste facility owners, operators, and technicians use the new application to observe system and environmental activity securely and in real-time on a mobile phone or device.
Featuring state-of-the-art technology, SCS MobileTools® provides users the ability to interact with a site or facility data, including site-specific monitoring and exceedance metrics for landfill gas, liquid levels, and surface emissions. Responsive, touch-enabled flow data charting is accessible, illustrating flow targets, reading dates, flow rates, and historical flow data analysis.
When compared year-over-year, generation and disposal trends produce information critical to assessing optimal options and solutions that represent significant savings for landfill gas Operations, Maintenance & Monitoring – OM&M programs. For this reason, the savings compound for regional or national operators.
For instance, monitoring and analyzing landfill gas generation and collection data against modeled estimates are valuable information. SCS MobileTools® handles the input, analysis, review, and export of landfill gas flow and related information, specifically flow rates, impacts on gas collection (e.g., extraction well liquid levels), and analytical data for data collection points.
In SCS’s release pipeline, SCS MobileTools® will include mapping and visualization functions in early 2021. SCS MobileTools® is available for download on the Apple App Store for iPhones and iPads, Google Play for Android.
SCS Engineers’ SCSeTools® platform and applications help facilities and companies operate more efficiently by continually gauging operational health and identify trends critical to operations and the environment.
SCS Technology Services®, the technology development practice within SCS Engineers, announces a new application for tracking and analyzing environmental data. The application expands the firm’s SCSeTools® platform, demonstrating its commitment to developing the most advanced data-driven technology in the environmental services industry.
Groundwater monitoring and compliance services are long-term and expensive responsibilities that generate enormous amounts of monitoring and laboratory data. SCS Groundwater™ is a tool to monitor and manage the data associated with operations and reporting requirements for various sites. Sites include active or closed landfills, plants, and impact sites such as former dry cleaners or industrial facilities.
The application also monitors and manages data effectively for clean groundwater applications such as groundwater basin management projects consistent with standard protocol under state and federal environmental compliance rules. SCS Groundwater™ collects and efficiently organizes groundwater monitoring and maintenance data providing those responsible for environmental compliance with a reliable, consistent, and cost-effective way to manage the large volume of information.
The application’s primary value is enabling users to set up a detailed monitoring plan for any number of events, including the sampling points to include and what analyses to perform at each point. Once the information upload is finished, the application checks incoming data against the plan to confirm all work is complete.
SCS Groundwater™ generates reporting components such as data tables, charts, graphs, and maps for compliance, reporting, and finding trends. For example, on a brownfield site, the compliance manager could upload historical monitoring data results, view the data trends over time, and then produce report tables and figures. Operators can also use the data in other applications for additional analysis or visualization.
SCS Engineers’ environmental solutions and technology directly result from our experience and dedication to industries responsible for safeguarding the environment as they deliver services and products. For information about SCS, visit the SCS eTools pages or enjoy our 50th Anniversary video to see the technology in action.
The SCSeTools® platform and applications help facilities operate more efficiently by continually gauging operational health and spot trends that help determine when and how to invest in infrastructure. Field staff, environmental compliance experts, brownfields, developers, and clients in the waste industry guide the technology designs. For additional information and demonstrations of these productivity-enhancing tools, please contact .
The events of 2020 have affected the economy, the way we conduct business, and even our social interactions. Now, more than ever, streamlining costs is key for public and private sector clients across the country. Enter groundwater monitoring projects.
Often overlooked as an opportunity to reduce costs, it’s an excellent place to start when examining the costly operational processes of a solid waste facility. Groundwater monitoring is often thought of as necessary for compliance requirements and overlooked when considering ways to reduce spending. However, the proactive review of all monitoring projects may offer monitoring reduction or even cessation opportunities.
SCS Engineers has successfully employed these strategies at several Florida landfills. For instance, in Marion County, the SCS team worked to get a cessation in landfill gas and groundwater monitoring at the Martel Closed Landfill. Hired to conduct routine post-closure monitoring, the team observed obvious trends in the data that were favorable to the County. If you consider that monitoring costs average $10,000 to $50,000 per year, the potential cost savings over ten years is $100,000 to 500,000.
Bottom line: you should take the initiative to ask a few simple questions to see if further examination is warranted. What if contaminants are naturally occurring? Is the data in the technical reports supporting conclusions that include reduction or cessation when appropriate? Are you simply meeting the minimum requirements of the permit without an eye on the future?
About the Author: SCS Project Director David Atteberry puts his 20+ years of environmental consulting and management experience to work for his clients. His technical experience includes geologic and hydrogeologic investigations involving hazardous waste, solid waste, environmental, and water supply. Dave’s technical areas of expertise include contamination assessments, remediation, site characterization, aquifer characterization, RCRA compliance, waste characterization, environmental due diligence, reserve budgeting, and field sampling techniques.
SCS Groundwater™ collects and efficiently organizes groundwater monitoring and maintenance data providing those responsible for environmental compliance with a reliable, consistent, and cost-effective way to manage, view, and assess large volumes of information.
The application’s primary value is enabling users to set up a detailed monitoring plan for any number of events, including the sampling points to include and what analyses to perform at each point. Once the information upload is complete, the application checks incoming data against the plan to determine if all work is completed.
Efficient and consistent data collection means better quality control, fewer violations, and less costly operations. The application is a relational data management system specifically designed for groundwater management. Learn about more benefits here.
Across the industry, stakeholders agree the next few years will be critical in shaping how landfills deal with PFAS and how the public perceives it. Waste trade associations, scientists, and a host of organizations are in the midst of conducting a number of studies looking closely at the issue, PFAS treatment options, the positive impact of recycling, and regulatory policies.
While there are sites noted in the article, there’s no practical way for most companies and landfills to respond at this time responsibly. Additionally, landfills are unique; no two are alike. Most human exposure to PFAS occurs through contaminated food. The majority of landfill leachate is pre-treated at the landfill before going to a wastewater treatment plant, where additional treatment occurs before discharge.
According to EREF President Dr. Bryan Staley, in the article, “The relative impact of leachate as a human exposure pathway needs further evaluation to understand its relative degree of importance as it relates to health implications.”
Dr. Gomathy Radhakrishna Iyer, landfill leachate and design expert for SCS Engineers, said some operators are waiting to see what regulations may come even as they work on accounting for potential compliance issues and seeking solutions. “When the clients are thinking of upgrading their treatment plans, some are definitely taking into consideration PFAS treatment,” Radhakrishna Iyer said.
“You’re spending millions of dollars, you need to do your due diligence, right? At this point, consideration should be given to PFAS treatment during the feasibility stages,” she said.
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.
We combine ITRC resources and our own to compile an updated library that we hope you find helpful. You can always contact one of our local Liquids Management or Landfill professionals too.
PFAS Behavior in the Environment
PFAS Concerns
PFAS Evaluations
PFAS Remediation
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).
ITRC Goals
SCS Engineers
