epa compliance

September 26, 2024

On Tuesday, September 25, the U.S. Environmental Protection Agency (EPA) issued two enforcement alerts addressing regulatory requirements and associated compliance issues at municipal solid waste landfills (MSW landfills). The alerts address Clean Air Act requirements that control the release of landfill gases (LFG), particularly methane, from MSW landfills.

These reminders represent compliance issues that EPA has flagged during enforcement actions. EPA thought they were important enough to publish these alerts for the benefit of landfill OM&M; expect state and local agencies to focus on these during their regulatory inspections.

The alerts provide an overview of the Clean Air Act regulatory requirements related to landfill air emissions and aim to help landfill owners, operators, and contractors comply with the law and take the necessary steps to avoid potential EPA enforcement actions.

The first enforcement alert, “EPA Investigations Find Municipal Solid Waste Landfill Operators are Failing to Properly Conduct Compliant Monitoring and Maintenance of Gas Collection and Control System,” is intended to remind MSW landfill owners, operators, and their consultants to conduct routine monitoring and maintenance of gas collection systems to ensure all landfill emissions are being properly captured and controlled.

The second enforcement alert, “MSW Landfill Operators Fail to Include Wastes from Total Degradable Waste-in-Place and Properly Sample Landfill Gas, Resulting in Underreported Emissions,” is intended to remind MSW landfill operators, owners, and their consultants to identify and document nondegradable wastes excluded in calculations properly and to collect representative LFG samples for non-methane organic compounds analysis and emission calculations.

If you are operating a landfill that gets an EPA Section 114 request for data, is having or has had an EPA inspection, or has received an EPA NOV, you may want to contact the compliance experts at SCS Engineers to seek advice on EPA’s perspective on rule history, interpretation, and assist how best to prevent or defend against enforcement actions.

Additional Resources

• Contact SCS Engineers
• In August 2023, EPA announced its first-ever climate enforcement initiative – Mitigating Climate Change – as one of six National Enforcement and Compliance Initiatives (NECIs) for fiscal years 2024-2027. The new climate change initiative focuses additional resources on reducing emissions of the highest impact super-pollutants – hydrofluorocarbons (HFCs) and methane.
• Following the mitigating climate change initiative, the EPA issued its “Climate Enforcement and Compliance Strategy” on September 28, 2023. The strategy requires EPA’s enforcement and compliance program to fairly and vigorously enforce the full array of EPA’s climate rules, including greenhouse gas reporting requirements and limits on other climate pollutants such as carbon dioxide and nitrous oxide.

May 2, 2024

EPA announces final rules intended to reduce pollution from fossil fuel-fired power plants, which the Agency claims will not disrupt reliable electricity delivery. These rules, finalized under separate authorities including the Clean Air Act, Clean Water Act, and Resource Conservation and Recovery Act, aim to reduce climate, air, water, and land pollution from the power sector.

The power sector has been investing long-term to transition to a clean energy economy based on rule changes like those recently announced by the EPA. This technical compliance alert summarizes four key rule changes, including:

• Mandate that existing coal-fired and new natural gas-fired power plants that plan to run long-term and all new baseload gas-fired plants control 90 percent of their carbon pollution.
• Tighten the Mercury and Air Toxics Standards (MATS) for coal-fired power plants by reducing the emissions standard for toxic metals by 67 percent and finalizing a 70 percent reduction in the emissions standard for mercury from existing lignite-fired sources.
• Reduce pollutants discharged through wastewater from coal-fired power plants by more than 660 million pounds per year, ensuring cleaner water for affected communities, including communities with environmental justice concerns.
• Require the management of coal ash placed in unregulated areas at the federal level, including previously used disposal areas that may impact groundwater.

Clean Air Act – NSPS
40 CFR Part 60

• EPA is repealing the Affordable Clean Energy (ACE) Rule, adopted during the Trump Administration to replace the Clean Power Plan (CPP) adopted during the Obama Administration to regulate GHG emissions. The D.C. Circuit Court vacated the ACE in 2021, and the CPP was struck down by the U.S. Supreme Court in 2022.
• EPA has determined that under the New Source Performance Standards (NSPS), the best system of emission reduction (BSER) for the longest-running existing coal-fired and new base load combustion turbines is “a proven add-on control technology—carbon capture and sequestration/storage (CCS).”
• For existing coal-fired electric generating units (EGUs) that intend to operate on or after January 1, 2039 (i.e., “long-term” units), and for new base load combustion turbine units, EPA will impose a numeric emission rate limit based on the application of CCS with 90% capture by January 1, 2032.
• In its press release, the EPA states that tax incentives from the Inflation Reduction Act allow companies to help offset the cost of CCS.
• Edison Electric Institute, an industry trade group, says, “CCS is not yet ready for full-scale, economy-wide deployment, nor is there sufficient time to permit, finance, and build the CCS infrastructure needed for compliance by 2032.” The courts will likely have to decide (again).
• EPA is finalizing revisions to the NSPS that do not include CCS for GHG emissions from other types of EGUs. States will have two years to submit State Implementation Plans (SIPs) for the new rules. SIPs must reflect meaningful engagement with stakeholders and may incorporate several provisions that the EPA says will encourage flexibility and help assure the electric grid’s reliability.

EPA Fact Sheet: https://www.epa.gov/system/files/documents/2024-04/cps-111-fact-sheet-overview.pdf

Clean Air Act – MATS and TRI

 The EPA is updating the Mercury and Air Toxics Standards (MATS) for coal- and oil-fired power plants to reduce hazardous air pollutant (HAP) emissions, with standards reflecting the latest advancements in pollution control technologies.

The final rule reduces the mercury emissions limit last set in 2020 by 70 percent for lignite-fired units and reduces the filterable particular emissions limit (a surrogate for other toxic metals) by 67 percent for all coal plants—while also requiring the use of continuous emission monitoring systems to provide real-time, accurate data to regulators, facility operators, and the public to ensure that plants are meeting these lower limits and that communities are protected year-round from pollution exposure.

For more information: https://www.epa.gov/stationary-sources-air-pollution/mercury-and-air-toxics-standards

Clean Water Act – Effluent Limitations Guidelines (ELG)
40 CFR Part 423

Wastewater discharge standards that apply to coal-fired power plants under the Clean Water Act are intended to reduce the possibility of toxic metals and other pollutants in wastewater entering lakes, streams, and other water bodies.

EPA’s final rule establishes technology-based discharge standards—known as Effluent Limitation Guidelines and Standards (ELGs)—that apply to four types of wastewater:

• Flue gas desulfurization wastewater,
• Bottom ash transport water,
• CCR leachate,
• “Legacy wastewater” stored in surface impoundments (for example, coal ash ponds).

Recognizing that some coal-fired power plants are in the process of closing or switching to less polluting fuels such as natural gas or renewable natural gas, the regulation includes flexibilities to allow these plants to continue to meet the 2015 and 2020 regulation requirements instead of the requirements contained in this final regulation. The EPA is creating a new subcategory for energy-generating units (EGUs) that permanently cease coal combustion by 2034.

EPA Fact Sheet: https://www.epa.gov/system/files/documents/2024-04/steam-electric-final-rule-fact-sheet_508.pdf

RCRA – Coal Ash/CCR Disposal and Impoundments
40 CFR Part 257

Under the Resource Conservation and Recovery Act, EPA is finalizing a rule for controlling and cleaning up contamination from the disposal of coal combustion residuals (CCR), or coal ash. The Agency is finalizing regulations for managing coal ash at inactive surface impoundments at inactive power plants and historical coal ash disposal areas. Inactive coal ash surface impoundments at inactive facilities are called “legacy CCR surface impoundments.”

This final rule extends a subset of EPA’s existing CCR requirements to these historic disposal units to remediate contamination and prevent further impacts. These requirements apply to all active and inactive facilities with legacy CCR surface impoundments. EPA is strengthening established groundwater monitoring, corrective action, closure, and post-closure care requirements for CCR management units (regardless of how or when that CCR was placed) at regulated facilities.

This rule becomes effective six months after publication of the final rule in the Federal Register. The compliance deadlines in the final rule provide additional time beyond the effective date for facilities to comply with certain technical criteria based on the amount of time EPA projects that facilities need to complete them, such as installing a groundwater monitoring system or developing a groundwater sampling plan and analysis program.

EPA Fact Sheet: https://www.epa.gov/system/files/documents/2024-04/legacy_ccrmu_final-_fact_sheet_april2024.pdf

Power Sector Compliance, Operations, and Reporting Resources:

• Environmental Compliance for Coal Combustion Residuals and Electric Utilities
• Carbon Sequestration & Deep Well Injection
• Renewable Energy
• Remote Monitoring and Control
• Find a compliance expert in your state.

April 30, 2024

EPA’s final action, also known as a risk management rule under the Toxic Substances Control Act (TSCA), is the second risk management rule to be finalized using the process created by the 2016 TSCA amendments.

Methylene chloride is used by consumers for aerosol degreasing and paint and coating brush cleaners, in commercial applications such as adhesives and sealants, and in industrial settings for making other chemicals. For example, methylene chloride is used in the production of more climate-friendly refrigerant chemicals.

Since 1980, at least 88 people have died from acute exposure to methylene chloride, largely workers engaged in bathtub refinishing or other paint stripping, even, in some cases, while fully trained and equipped with personal protective equipment. While EPA banned one consumer use of methylene chloride in 2019, use of the chemical has remained widespread and continues to pose [a] significant and sometimes fatal danger to workers. EPA’s final risk management rule requires companies to rapidly phase down manufacturing, processing, and distribution of methylene chloride for all consumer uses and most industrial and commercial uses, including its use in home renovations.

Consumer use [of methylene chloride] will be phased out within a year, and most industrial and commercial uses will be prohibited within two years.

For a handful of highly industrialized uses, EPA has created a Workplace Chemical Protection Program. This workplace chemical protection program has strict exposure limits, monitoring requirements, and worker training and notification requirements that will protect workers from cancer and other adverse health effects caused by methylene chloride exposure.

Uses that will continue under the Workplace Chemical Protection Program are highly industrialized and important to national security and the economy. These are uses for which EPA received data and other information that shows workplace safety measures to fully address the unreasonable risk could be achieved. These uses include:

1. Use in the production of other chemicals, including refrigerant chemicals that are important in efforts to phase down climate-damaging hydrofluorocarbons under the bipartisan American Innovation and Manufacturing Act.
2. Production of battery separators for electric vehicles.
3. Use as a processing aid in a closed system.
4. Use as a laboratory chemical.
5. Use in plastic and rubber manufacturing, including polycarbonate production.
6. Use in solvent welding.

Additionally, specific uses of methylene chloride required by the National Aeronautics and Space Administration, the Department of Defense, and the Federal Aviation Administration will also continue with strict workplace controls because sufficient reductions in exposure are possible in these highly sophisticated environments, minimizing risks to workers.

Compliance Under the Risk Management Rule

For uses of methylene chloride continuing under the Workplace Chemical Protection Program, most workplaces will have 18 months after the finalization of the risk management rule to comply with the program and would be required to periodically monitor their workplace to ensure that workers are not being exposed to levels of methylene chloride that would lead to an unreasonable risk. In consideration of public comments on the proposal, EPA extended the compliance timeframe to give workplaces ample time to put worker protections in place.

EPA also revised several other aspects from the proposal including ensuring the Workplace Chemical Protection Program applies to the same uses whether they are federal or commercial uses, establishing a de minimis concentration, and provisions to strengthen and clarify aspects of the Workplace Chemical Protection Program such as monitoring requirements.

EPA will also host a public webinar to explain what is in the final rule and how it will be implemented. The agency will announce the date and time in the coming weeks.

For More Information

• Please read EPA’s page Risk Management for Methylene Chloride
• Pre-publication Rule
• Risk Management Plans and Process Safety Management
• Industrial Health & Safety Training

April 23, 2024

The U.S. Environmental Protection Agency finalized a rule that strengthens its process for conducting risk evaluations on chemicals under the Toxic Substances Control Act (TSCA). These improvements to EPA’s processes advance the goals of this important chemical safety law, ensure that TSCA risk evaluations comprehensively account for the risks associated with a chemical, and provide a solid foundation for protecting public health, including workers and communities, from toxic chemicals. The rule also includes changes to enhance environmental protections in communities overburdened by pollution, complementing the Administration’s environmental justice agenda.

The 2016 TSCA amendments require that EPA establish a procedural framework rule on the process for conducting chemical risk evaluations. TSCA risk evaluations are the basis for EPA’s risk management rules. Although EPA finalized a risk evaluation framework rule in 2017, that rule was challenged in court. EPA’s final rule includes revisions made to respond to the court’s ruling, as well as several changes to improve EPA’s process for TSCA risk evaluations, including:

• Consideration of real-world exposure scenarios such as multiple exposure pathways (e.g., in air and water) to the same chemical, and combined risks from multiple chemicals when EPA has the scientific information to do so, which may be particularly important for communities who face greater exposures or susceptibilities to chemicals than the rest of the general population.
• A requirement that risk evaluations are comprehensive in scope and do not exclude conditions of use or exposure pathways.
• Clarifications to ensure EPA appropriately considers risks to all workers in its risk evaluations.
• Consideration of chemical uses that may be required for national security or critical infrastructure by other Federal agencies.
• Assurance the agency will continue to use the best available science to conduct risk evaluations, that decisions are based on the weight of the scientific evidence and that risk evaluations will be peer reviewed in accordance with both federal and EPA guidance.
• Discussion of chemical-specific fit-for-purpose approaches that allow for varying types and levels of analysis so that risk evaluations focus less rigorously on the conditions of use that are expected to pose low potential risk and can reliably be completed within the timeframes required by the statute.
• A clear requirement for risk evaluations to culminate in a single risk determination on the chemical substance, rather than on individual chemical conditions of use in isolation, and improved communications regarding the uses that significantly contribute to the unreasonable risk.
• New procedures and criteria for whether and how EPA will revise scope and risk evaluation documents, to improve transparency.
• Adjustments to the process for submission and review of manufacturer requests for risk evaluations of chemicals to better align with the process and timeline associated with EPA-initiated risk evaluations, while also ensuring that the agency can use the authorities provided under the law for gathering any needed additional information on such chemicals.
• A requirement that risk evaluations must explicitly consider overburdened communities when identifying potentially exposed and susceptible populations as relevant to the risk evaluation.

EPA announced many of the changes included in the final rule in 2021 and has incorporated them into TSCA risk evaluation activities over the past three years. EPA then proposed a revised procedural framework rule in October 2023 and, after considering public comment on the proposed rule, released today’s final rule. EPA is submitting this document for publication in the Federal Register (FR).

The procedures outlined in the rule apply to all risk evaluations initiated 30 days after the date of publication of the final rule or later. For risk evaluations that are currently in process, EPA expects to apply the new procedures to those risk evaluations to the extent practicable, taking into consideration the statutory requirements and deadlines.

TSCA Risk Evaluation Process

The Risk Evaluation process is the second step, following Prioritization and before Risk Management, in EPA’s existing chemical process under TSCA. The purpose of risk evaluation is to determine whether a chemical substance presents an unreasonable risk to health or the environment, under the conditions of use, including an unreasonable risk to a relevant potentially exposed or susceptible subpopulation. As part of this process, EPA must (1) evaluate both hazard and exposure, (2) exclude consideration of costs or other non-risk factors, (3) use scientific information and approaches in a manner that is consistent with the requirements in TSCA for the best available science, and (4) ensure decisions are based on the weight-of-scientific-evidence. Learn more about the TSCA risk evaluation process.

Additional Resources

• Pre-publication copy of the Procedures for Chemical Risk Evaluation Under the Toxic Substances Control Act (TSCA) 
• How will this impact my facility or business? Contact
• Risk Management

April 10, 2024

On April 10, the Federal Administration issued the first-ever national, legally enforceable drinking water standard to protect communities from exposure to harmful per-and polyfluoroalkyl substances (PFAS), also known as ‘forever chemicals.’ Exposure to PFAS has been linked to deadly cancers, impacts to the liver and heart, and immune and developmental damage to infants and children. This final rule represents the most significant step to protect public health under EPA’s PFAS Strategic Roadmap.

EPA is also making funding available to help ensure that all people have clean and safe water. In addition to today’s final rule, EPA is announcing nearly $1 billion in newly available funding to help states and territories implement PFAS testing and treatment at public water systems and to help owners of private wells address PFAS contamination. This is part of a $9 billion investment through the Bipartisan Infrastructure Law to help communities with water impacted by PFAS and other emerging contaminants – the largest-ever investment in tackling PFAS pollution. An additional $12 billion is available through the Bipartisan Infrastructure Law for general drinking water improvements, including addressing emerging contaminants like PFAS.

The enforceable drinking water PFAS regulations are finalized today and posted here. EPA PFAS regulations under the Safe Water Drinking Act page.

EPA finalized a National Primary Drinking Water Regulation (NPDWR) establishing legally enforceable levels, called Maximum Contaminant Levels (MCLs), for six PFAS in drinking water. PFOA, PFOS, PFHxS, PFNA, and HFPO-DA as contaminants with individual MCLs, and PFAS mixtures containing at least two or more of PFHxS, PFNA, HFPO-DA, and PFBS using a Hazard Index MCL to account for the combined and co-occurring levels of these PFAS in drinking water. EPA also finalized health-based, non-enforceable Maximum Contaminant Level Goals (MCLGs) for these PFAS.

The final rule requires:

• Public water systems must monitor for these PFAS and have three years to complete initial monitoring (by 2027), followed by ongoing compliance monitoring. Water systems must also provide the public with information on the levels of these PFAS in their drinking water beginning in 2027.
• Public water systems have five years (by 2029) to implement solutions that reduce these PFAS if monitoring shows that drinking water levels exceed these MCLs.
• Beginning in five years (2029), public water systems that have PFAS in water for drinking, which violates one or more of these MCLs must take action to reduce levels of these PFAS in their drinking water and must provide notification to the public of the violation.

EPA estimates that between about 6% and 10% of the 66,000 public water systems subject to this rule may have to take action to reduce PFAS to meet these new standards. All public water systems have three years to complete their initial monitoring for these chemicals. They must inform the public of the level of PFAS measured in their drinking water. Where PFAS is found at levels that exceed these standards, systems must implement solutions to reduce PFAS in their drinking water within five years.

The new limits in this rule are achievable using a range of available technologies and approaches including granular activated carbon, reverse osmosis, and ion exchange systems. Drinking water systems will have flexibility to determine the best solution for their community and essential services that require wastewater treatment.

Additional Resources:

• EPA will host a series of webinars to provide information to the public, communities, and water utilities about the final PFAS drinking water regulation. To learn more about the webinars, please visit EPA’s PFAS water regulation webpage.
• EPA has also published a toolkit of communications resources to help drinking water systems and community leaders educate the public about PFAS, where they come from, their health risks, how to reduce exposure, and about this rule.
• Contact a wastewater treatment expert at service.scsengineers.com to discuss the most appropriate treatment plan for your site, plant, or facility.

February 7, 2024

Proposed PFAS Hazardous Constituents Under RCRA

The Environmental Protection Agency (EPA) is proposing to amend its regulation under the Resource Conservation and Recovery Act (RCRA) by adding nine specific per-and polyfluoroalkyl substances (PFAS), their salts, and their structural isomers to its list of hazardous constituents. EPA’s criteria for listing substances as hazardous constituents under RCRA require that they have been shown in scientific studies to have toxic, carcinogenic, mutagenic, or teratogenic effects on humans or other life forms.

Entities potentially affected by this action include hazardous waste treatment, storage, and disposal facilities (TSDFs) with solid waste management units (SWMUs) that have released or could release any of the PFAS proposed to be listed as RCRA hazardous constituents. EPA has identified 1,740 such facilities, which could be subject to additional corrective action requirements (under RCRA section 3004(u) and (v)) to address releases not already subject to corrective action under EPA’s corrective action regulations.

The nine PFAS and common uses are as follows:

1. Perfluorooctanoic acid (PFOA; CASRN 335-67-1). PFOA is an eight-carbon molecule with seven fully fluorinated carbon atoms, and one carboxylic acid functional group used as a processing aid to produce fluoropolymers found in cleaning agents, waxes, aqueous film-forming foam (AFFF), and other products.
2. Perfluorooctanesulfonic acid (PFOS; CASRN 1763-23-1). PFOS is a fully fluorinated eight-carbon molecule with one sulfonic acid functional group used in AFFF surface treatments of textiles to provide oil and water resistance, metal plating, and other uses and industries.
3. Perfluorobutanesulfonic acid (PFBS; CASRN 375-73-5). PFBS is a fully fluorinated four-carbon molecule with one sulfonic acid group. It has been used as a replacement for PFOS used in manufacturing paints and cleaning agents, metal plating, AFFF, to provide oil and water resistance, and other uses and industries.
4. Hexafluoropropylene oxide-dimer acid (HFPO-DA or GenX; CASRN 13252-13-6). HFPODA is a six-carbon molecule consisting of five fully fluorinated carbon atoms, one ether functional group, and one carboxylic acid functional group. HFPO-DA is a chemical associated with GenX processing aid technology used to make fluoropolymers without PFOA.
5. Perfluorononanoic acid (PFNA; CASRN 375-95-1). PFNA is a nine-carbon molecule with eight fully fluorinated carbon atoms and one carboxylic acid functional group. It has been used as a processing aid to produce fluoropolymers and has been used or found in metal plating, cleaning agents, waxes, AFFF, energetic materials, and other products.
6. Perfluorohexanesulfonic acid (PFHxS; CASRN 355-46-4). PFHxS is a fully fluorinated six-carbon molecule with one sulfonic acid functional group used in AFFF surface treatments of textiles to provide oil and water resistance, in metal plating, and in other uses and industries.
7. Perfluorodecanoic acid (PFDA; CASRN 335-76-2). PFDA is a ten-carbon molecule with nine fully fluorinated carbon atoms and a carboxylic acid functional group. It has been used as a processing aid to produce fluoropolymers and has been used or found in metal plating solutions, cleaning agents, waxes, AFFF, and other products.
8. Perfluorohexanoic acid (PFHxA; CASRN 307-24-4). PFHxA is a six-carbon molecule with five fully fluorinated carbon atoms and a carboxylic acid functional group. It has been used or found in metal plating solutions, cleaning agents, waxes, AFFF, and other products.
9. Perfluorobutanoic acid (PFBA; CASRN 375-22-4). PFBA is a four-carbon molecule with three fully fluorinated carbon atoms and one carboxylic acid functional group. It has been used or found in metal plating, cleaning agents, waxes, AFFF, energetic materials, and other products.

EPA will collect comments on this PFAS to RCRA’s hazardous constituents proposal for 60 days once published in the Federal Register. Read a prepublication copy of this proposal.

Submit your comments on the Federal eRulemaking Portal: https://www.regulations.gov and identified by Docket ID No. EPA-HQ-OLEM-2023-0278.

As a result of this proposed rule, if finalized, when imposing corrective action requirements at a facility, these PFAS would be among the hazardous constituents expressly identified for consideration in RCRA facility assessments and, where necessary, further investigation and cleanup through the RCRA corrective action process at RCRA treatment, storage, and disposal facilities. Contact SCS Engineers for guidance about your facility at .

Additional Resources:

For additional information regarding EPA’s proposed RCRA PFAS rules, see:

• https://www.epa.gov/superfund/advanced-notice-proposed-rulemaking-potential-future-designations-and-polyfluoroalkyl and
• https://www.epa.gov/hw/proposal-clarify-authority-address-releases-hazardous-waste-treatment-storage-and-disposal

January 11, 2024

EPA proposes stronger air pollution standards for large facilities that burn municipal solid waste

Partial reprint of EPA’s Announcement dated January 11, 2024

WASHINGTON – The U.S. Environmental Protection Agency on Thursday announced a proposal to strengthen Clean Air Act standards for large facilities that burn municipal solid waste. If finalized, the updated standards would reduce emissions of nine pollutants, including smog- and soot-forming sulfur dioxide and nitrogen oxides, by approximately 14,000 tons per year, improving air quality for overburdened communities living near these facilities. These proposed standards reflect current technologies available to control pollution in a cost-effective fashion.

The proposed standards would apply to 57 facilities with 152 units that have the capacity to combust more than 250 tons per day of municipal solid waste. Nearly 4 million Americans live within 3 miles of these large facilities, which are disproportionately located in low-income communities and communities of color.

The proposed standards are based on emission levels achieved by the best controlled and lower-emitting sources, and limit emissions of nine pollutants: particulate matter, sulfur dioxide, hydrogen chloride, nitrogen oxides, carbon monoxide, lead, cadmium, mercury, and dioxins/furans.

The Clean Air Act requires EPA to evaluate these standards every five years in order to take into account developments in pollution control technologies and techniques. EPA last revised these standards in 2006.

After accounting for compliance costs of the rule, EPA estimated the net present value of health benefits from the proposed rule, due to reductions in particulate matter and ozone alone, to be up to $14 billion over 20 years. Reductions of mercury, lead, and other hazardous air pollutants required by the proposal are expected to result in additional unquantified economic and public health benefits.

EPA will accept comment on the proposal for 60 days after publication in the Federal Register. EPA will hold an informational webinar and will announce details on its website shortly.

Additional Resources:

• Read more information on the proposal and upcoming webinar for large municipal waste combustors.
• For specific questions on your facility – please contact for help from our Clean Air Act National Experts Pat Sullivan and Josh Roth.
• Clean Air Act

October 20, 2023

This year’s annual Illinois Manufacturers Association Environment and Energy Conference attracted many attendees and presenters from industry, consultants, and regulatory officials. Notable takeaways included a passionate appeal from the Illinois Environmental Protection Agency (IEPA) to be patient and proactive on permitting issues as the agency expands its workforce to support Illinois manufacturers’ economic growth and expansion plans. IEPA notes that they seek a partnership with industry rather than an antagonistic relationship and strongly support the state’s development while acknowledging they are bound to federal regulations. The more timely, accurate, and clear permit applications can be prepared, the faster the approval process.

Clean Air Act Changes

Major focuses of the IEPA remain on tracking current and proposed National Ambient Air Quality Standards (NAAQS), which currently designate East St. Louis and Chicago areas as non-attainment zones for ozone and portions of Madison County as non-attainment zones for sulfur dioxide. Proposed reductions in the allowable limits for particulate matter (PM) 2.5 micrometers (µg/m³) under the Clean Air Act, which could go into effect at any time, will result in the designation of additional non-attainment areas in Illinois and, accordingly, far greater difficulty in air permitting for new or expanding facilities. The current annual average primary standard for PM 2.5 is 12 µg/m³, whereas the proposed standard will likely fall to between 9-10 µg/m³.

Permitting and Enforcement of NPDES

Presenters also noted that in Illinois, the IEPA issues National Pollutant Discharge Elimination System (NPDES) permits rather than the USEPA. However, USEPA can still issue enforcement violations. Furthermore, many wastewater treatment plants have pre-treatment effluent requirements for industrial users to address potential pollution problems as part of their NPDES permits. These requirements will become increasingly strict when/if PFAS are declared a hazardous substance under CERCLA.

Extended Producer Responsibility

Another noteworthy topic was the burgeoning practice of Extended Producer Responsibility (EPR). Much like RCRA, which requires cradle-to-grave tracking of hazardous materials, EPR deals with tracking non-hazardous materials, such as packaging, from creation through disposal with the goal of reducing landfill wastes via industry-subsidized source reduction and recycling programs. While Illinois is not currently one of the six states (California, Colorado, Maine, Oregon, New Jersey, and Washington) with mandated EPR or equivalent laws, multiple bills proposed in Illinois and elsewhere would require these types of programs for many market segments. Manufacturers are considering what steps they would need to take if a similar bill passes in Illinois. Particularly noteworthy is that these laws apply to states where products are distributed, not merely produced.

Sustainability and Decarbonization in the Energy Sector

Finally, presenters from various energy companies and consulting firms spoke about the path forward for sustainability and decarbonization in the energy sector, noting that it must combine natural gas, nuclear power, and traditional renewables like wind and solar to meet customer needs. SCS’s very own Dr. Charles Hostetler spoke on carbon capture methods (such as geologic sequestration of carbon in Class VI wells) and other operational strategies of manufacturers, electric utilities, solid waste facility owners/operators, and other property owners/developers to address the evolving landscape of environmental regulations.

Industry/Manufacturing Essentials

Keep close tabs on new legislation and regulation changes to assure compliance and avoid costly fines or operational delays. Partnerships with environmental consultants who have strong, established relationships with federal, state, and local agencies and have their finger on the pulse of the environmental landscape are the best way to accomplish your goals as the regulatory scene changes.

About the Author: Rachel McShane, LEP, has over 15 years of experience in environmental due diligence projects (Phase I, II and III Environmental Site Assessments) as well as Brownfields redevelopment, risk-based corrective action, and remediation projects. She is familiar with National Environmental Policy Act (NEPA) environmental assessments, vapor investigations and mitigation, radon, asbestos, lead-based paint surveys, and leachate monitoring/solid waste management. Reach Ms. McShane at  or via LinkedIn.

September 22, 2023

Commercial Carbon Capture and Sequestration in the US

The US is home to the largest number of commercial carbon capture and sequestration (CCS) projects worldwide, with approximately 50 new projects announced in 2021, according to the Global CCS Institute. SCS contributes expertise to several ongoing and groundbreaking carbon dioxide geologic sequestration projects. These projects have highly advanced permitting and monitoring requirements.

Research published in a report by the Congressional Research Service defines three main types of sites ideal for underground CO₂ injection and sequestration: depleted oil and gas reservoirs, deep saline reservoirs, and un-mineable coal seams. In each case, CO₂ in a supercritical state is injected into a porous rock formation below ground that holds, or previously held, fluids. When injected at depths greater than half a mile, the pressure keeps the injected CO₂ entrained within the formation fluids, where the CO₂ will subsequently dissolve.

Selecting a Site

The target geological injection interval must have an overlying impermeable caprock, such as shale, so the injected CO₂ doesn’t migrate into overlying formations, most specifically, the underground source of drinking water. Fortunately for geoscientists and engineers, most of the technology used to assess the subsurface was initially developed by the petroleum industry, including a variety of geophysical techniques, including seismic reflection.

Using Seismic Reflection Technology

At SCS, our team uses the same seismic reflection technology and methodology developed by the oil and gas industry to evaluate the subsurface. Seismic reflection is a powerful tool when used properly and allows us to interpret the depositional background of the system and identify permeable and impermeable units. Seismic reflection involves generating seismic waves (the source) and measuring the two-way travel time taken for the waves to travel from the source, reflect off an interface, and be detected by an array of receivers at the surface. The reflected signal is based on the density-velocity contrast at the interface. Depending upon the type of source and receivers, seismic reflection, once recorded and processed, provides 2 or 3-D imagery of stratigraphic boundaries and geologic structure –all at depths ranging from hundreds of meters to several kilometers.

In-house experts enable SCS to utilize this amazing tool, which enables teams across the organization to see where the best areas for injection are by interpreting seismic stratigraphy. We can determine the continuity of a layer and the presence (or absence) of faults and fractures. The data can also help us determine the type of fault and whether it is a sealing or a transmissive fault. For example, a fault-bound anticline (when the rocks push up from stress changes) may provide a stratigraphic trap for hydrocarbon and can potentially store CO₂.

We use seismic reflection in the initial phases of a project to determine the depths and lateral extent of known lithology. We employ previously mapped lithologic units to correlate the “images” created in seismic profiles to existing formations and, in doing so, perform a “check” on the seismic interpretation.

Long Term Benefits

Seismic reflection provides significant input when choosing a reservoir or siting a well; however, its use doesn’t end with an initial site assessment. The technology provides robust methods for monitoring the CO₂ plume and interpreting changes to the subsurface during and post-injection. SCS has two Class VI injection projects where seismic reflection data was employed to identify the target injection zones and seals. The next step will be using the data to look at the subsurface relative to the injection well using downhole sensors, a process known as vertical seismic profiling.

The requirements surrounding the Class VI permitting process are complicated, but SCS has in-house experts with the skills to employ seismic reflection. Teams continue to hone their skills in this area as clients value and trust partners who can demonstrate a thorough understanding of permitting carbon sequestration projects.

The Class VI permit application typically takes 18 to 24 months to receive approval. The process is laborious and expensive. Demonstrating expertise here is critical as SCS Engineers continues to play an integral role in advancing supercritical CO₂ projects throughout North America.

Additional Resources and Educational Materials:

• General Information Uses to Reduce Carbon Footprints Safely
• Understanding the CCS Project Life Cycle – Blog and Video
• Overview and Guide to Carbon Sequestration Economic Incentives – Article
• Flow Modeling for CO2 Storage Efficiency – Blog and Whitepaper
• Protecting Drinking Water – Video
• Computational Modeling to Right-Size Sequestration Projects – Video

About the Author: Candy Elliott, PG, Senior Geologist, holds degrees in geology and geophysics and has 17 years of experience in assessment and remediation, including comprehensive geologic and hydrogeologic site assessments in several states. Her projects include site characterization, site assessment and remediation, brownfields, groundwater monitoring and reporting, groundwater corrective action, mining, and other industrial facility or site development projects. She supports new and existing geologic permitting assignments for waste clients and facilities. Contact Ms. Elliott at or LinkedIn.

August 16, 2023

Air Emissions Reporting Requirements – AERR

The proposed AERR rule would require nearly 130,000 facilities to report air toxics emissions directly to EPA. It would also give states the option to collect the air toxics data from industry (rather than states) and report it to EPA, provided the Agency approves their program. This proposed action would allow for EPA to annually collect (starting in 2027) hazardous air pollutant (HAP) emissions data for point sources in addition to continuing the criteria air pollutant and precursor (CAP) collection in place under the existing AERR. 

Here are some key things to know about the proposed rule from the EPA website:

1. It would require air toxics (hazardous air pollutant) emissions reporting. While most states voluntarily report air toxics emissions data to EPA now, reporting is not consistent nationwide. The proposal would require many industrial facilities to report air toxics emissions data and offers states the option to report emissions on behalf of the industry sources in their states.
2. It would mean that more facilities must report emissions every year by using the same emissions thresholds every year to determine whether a facility’s detailed emissions information must be reported.
3. It would fill reporting gaps for some portions of Indian country and federal waters. The AERR proposal would require industry to report emissions for certain facilities that operate in those areas and that currently are not reported.
4. It includes provisions to limit the burden on small businesses. The proposal includes flexibilities such as allowing certain small businesses to report a facility’s total air toxics emissions instead of detailed data and exempting many collision repair shops from air toxics reporting requirements.
5. It would provide EPA information that would help the Agency improve its estimates of emissions from prescribed fires. EPA is committed to helping communities and our federal, state, local, and tribal partners manage the health impacts of smoke from wildland fires, including prescribed fires. Prescribed fire is a land management tool that can reduce the likelihood of catastrophic wildfires by reducing the buildup of unwanted fuels.

Additional Resources:

• EPA will take comment on the AERR proposal for 70 days after it is published in the Federal Register. Proposal and webinar registration here.
• Contact or find your state’s air emissions expert.
• Air Compliance Reporting