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Navigating CCR compliance under recent EPA determinations

Navigating CCR compliance under recent EPA determinations

The Coal Combustion Residuals (CCR) Rule was initiated in 2015 to address potential risks related to the storage of coal ash and related byproducts produced by power utilities. As a result of several legal decisions, the U.S. Environmental Protection Agency (EPA) has recently begun to issue determinations for Part A and B applications submitted by utilities. In addition, two consent decrees reflecting enforcement actions against power utilities have recently been handed down.

The CCR Rule includes provisions for groundwater monitoring of existing and new CCR landfills and impoundments. The rule was originally written to be “self-implementing,” but these recent actions show that good-faith compliance decisions are now being second-guessed by the EPA. The Part A and Part B applications are voluntary actions that require full compliance with the rule’s groundwater provisions in order to be accepted. The consent decrees are enforcement actions under the rule that included fines with strict requirements and deadlines for compliance measures. Most of the information used by EPA was based upon a review of facilities’ published reports on required CCR internet websites, as well as subsequent information requests from the EPA.

Here, we take a closer look at the CCR Rule, Part A and B determinations, and consent decrees to determine the basis for the EPA’s current citations and how you can best ensure compliance moving forward.

Initial challenges of the CCR Rule

One of the initial challenges of the CCR Rule was that it was intended to be self-implementing. Enforcement would come from citizen lawsuits under the Resource Conservation and Recovery Act (RCRA) and be facilitated by requirements to post reports and documents to a publicly accessible website for each owner/operator.

The rule relied heavily on the judgement of a qualified professional engineer (QPE) tasked with making decisions based on a professional standard of care. With no specific CCR Rule guidance from the EPA or regulators to negotiate with, QPEs were using sound engineering judgment based on the rule’s often nondescript language, supported by other published guidance, training, experience, and peer reviews. As a result, no one really knew what the EPA considered acceptable or unacceptable. That is, until now.

What are Part A, Part B, and consent decrees? How are they different?

There are seven Part A determinations, six Part B determinations, and two consent decrees (for a total of 15 separate facilities) that now offer a vast treasure trove of information for owners, operators, and QPEs who want to understand exactly what the EPA considers unacceptable. To summarize:

  • Part A applies to facilities with unique circumstances that required an extension to the mandatory closure dates because they had a need for alternative capacity or, in some cases, the plant was going to close by “date certain” after the effective date for unlined impoundments to close.

  • Part B applies to sites that wished to gain relief to close their CCR impoundments based on an alternative to the prescriptive liner requirements in the rule.

  • Acceptance of Part A or Part B demonstrations is contingent on full compliance with the other provisions in the rule and, specifically, the groundwater monitoring requirements.

  • While Part A and Part B represent voluntary requests for EPA approval, the consent decrees are strictly related to the EPA exercising enforcement authority under the CCR Rule.

Barr has conducted extensive research into these determinations to improve our own quality control across multiple client sites and respond to client inquiries as to which potential past decisions on CCR matters may lead to future inquiry from the EPA or EPA-approved state CCR programs. Our findings indicate that many of the alleged deficiencies were related to four primary categories, shown below. In most cases, multiple deficiencies were cited for multiple CCR units (e.g., most sites had multiple CCR units, but each deficiency was counted only once per site). Each category is described below with several highlighted details including commonly utilized practices that many QPEs and clients still consider standard acceptable methods.

Four categories of EPA’s alleged deficiencies

EPA rationale for deficiency by category and site type

1. Site characterization and monitoring networks

Site characterization and monitoring network issues were cited 48 times by the EPA at one or more of the 15 total sites included in this study. These include 7 Part A, 6 Part B, and 2 consent decree mentions. Specific issues cited by the EPA under this category include:

  • Lack of rigor—aquifers, confining layers, properties not adequately defined, or minimal amount of information provided

  • Lack of monitoring or untimely monitoring

  • Too few borings or wells to define flow conditions

  • Wells spaced too widely apart

  • Wells too far from waste boundary

  • Screen lengths too long or dry wells

  • Unmonitored downgradient pathways

  • Variations in flow direction (up, down, side) ignored

These plots show the actual vs. modeled variations in flow direction that are used to demonstrate that the monitoring network provides adequate lateral spacing to detect a release downgradient of a CCR facility. This analysis is a variant of a tool we call a Pinder Plot (after Pinder et al, 1981), which can be useful in defending an allegation that a monitoring network is inadequate in terms of well spacing, especially when long-term monitoring data is not yet available to otherwise show variation in flow directions.

2. Certifications and reporting

Certifications and reporting were cited as deficient 42 times forming the second-most common issue described as inadequate by EPA. This category was assigned in order to differentiate between the technical issues cited above and the failure to appropriately report or analyze the required data. For example, installing only the minimum of three wells may or may not have represented a site characterization failure, but the EPA specifically identified it as inadequate in regard to the process of certifying the network and providing the required information to support that certification. In this example, the failure was in not providing the rule-required explanation as to why there were only three downgradient wells. Notable issues in this category include:

  • Failure to provide an explanation for a minimum of 3 downgradient wells (as above)

  • Reporting limits too high

  • Missed Statistically Significant Increases (SSIs)

  • Network certification, including wells that were cited in alternative source demonstrations as faulty

  • Missing reports or missed deadlines

  • Reports with missing rule-required information

  • Failure to recertify networks after modifications

  • Inadequate analyses for assessment of corrective measures and remedy selection reports (e.g., failure to address reversibility and reliance on dispersion for monitored natural attenuation)

3. Statistics

The CCR rule requires that decisions regarding the process of moving from background data collection to detection monitoring, then to assessment monitoring and eventually corrective action are based on statistical methods. Therefore, statistics become a key element of compliance. Statistical related issues were cited as deficient 40 times at the 15 sites, with most of the citations coming from the Part B demonstrations. Statistics are a key element of the rule as they are the primary means by which the performance of the CCR unit is judged in protecting groundwater. Key findings in this category include:

  • Failure to conduct statistical testing

  • Inappropriate upgradient wells (alleged to be by CCR unit or other background source)

  • Use of intrawell prediction limits or control charts

  • Inadequate distribution testing or lack of distribution data

  • Non-parametric limit errors

  • Low statistical power (number of upgradient samples not enough)

  • Outlier testing (not performed or masking impact)

  • 1of 2 timing (stat methods don’t override rule deadlines)

  • Lower Prediction Limit for pH (two sided limit not described)

  • Non-parametric (cherry picking highest value without justification from distribution data)

  • Independence (too many samples spaced too close together; must be based on travel times)

4. Alternative source demonstrations (ASDs)

We decided to make a special category just for ASDs, even though in most cases they are a subset of statistical determinations. This is because ASDs are triggered by an SSI using statistical measures, but the level of detail and arguments made by the EPA provide valuable insight into possible improvements. In our opinion, this category is also quite notable in that only one of 43 ASDs discussed by the EPA were deemed acceptable. Let that sink in for a moment: Just one instance out of 43 separate ASDs, each certified and completed under the direction of a QPE, was deemed adequate by the EPA. The lone exception was a demonstration for pH due to a faulty pH meter. In another example, the EPA appears to approve of the use of stable isotope data to compare ash samples with groundwater, but that example was actually interpreted as a line of evidence against the ASD (i.e., evidence that the CCR unit was, in fact, impacting groundwater in a downgradient well). Commonly cited deficiencies included:

  • Lack of rigor—asserting a hypothesis unsupported by site specific data or use of regional background data

  • Travel time estimates—stating the estimated travel time is too great for the network to have detected a release

  • Use of piper plots or ratios to compare groundwater to surface water or leachate

  • Citing a lack of complete parameter suite or argument that a release would affect multiple wells with multiple Appendix III parameters (boron, calcium, chloride, fluoride, pH, sulfate and total dissolved solids (TDS))

  • Use of historical data without demonstrating the data was not preferentially selected

  • Historical impacts from other CCR or non-CCR units


Based on our detailed analysis of these 15 facilities and a follow-up review of other public reports, we believe the EPA would likely find deficiencies in many of the CCR-related reports published under the rule. The 98 percent rate of ASD failures suggests a high probability for future compliance issues at many facilities. Some observations to consider going forward include:

  • The site characterization requirements in the rule are being interpreted more like a checklist than the general practices that typically constitute a standard of care. Inferences from indirect sources of information, such as interpolation based on geologic and hydrogeologic principles, are important, but not as important to the EPA as placing borings and wells at regular lateral and vertical spacing intervals and integrating them into a cohesive conceptual site model (CSM).

A CSM is a simplified representation of what can often involve complex subsurface conditions. As shown above, geologic, geochemical, and ground flow information needs to be characterized both horizontally and vertically to support the development of a monitoring network and, if necessary, justify decisions about corrective measures.
  • Reporting and certifications are in most cases the easiest items to rectify. It is clear from the EPA’s work that it is never too late to go back and revise past reports and that certifications are living documents that should be updated as new information becomes available or changes occur (e.g., to monitoring networks or statistical methods). The question remains on how compliance questions will be resolved when either state-approved or federal permit programs are in place and there is more of the usual give-and-take with regulators before actions are complete rather than the uncertainty inherent with after-the-fact enforcement.

  • Furthermore, the anticipated Legacy CCR Rule means that many pre-rule impoundments and landfills may be subject to the CCR rule requirements. This new rule suggests that the lessons learned from these determinations might prove useful in improving compliance in characterizing and monitoring sites that were previously excluded from the rule. Check back in the near future as we investigate this anticipated rule further.

Next steps

We believe that owners and operators of CCR facilities should consult with their qualified professional engineer (QPE) and assess whether adjustments should be made to past reports and methods based on these findings. Barr’s CCR experts can help you better understand these findings and take actions to improve your compliance. Barr can assist you and your QPE in offering more details on these determinations and, if appropriate, offer an independent review of your previous CCR reports and certifications to offer suggestions on reasonable actions that might be considered. Contact our team to learn more about Barr’s environmental compliance support services.

About the authors

Jim Aiken, vice president, senior hydrogeologist, has more than 20 years of CCR-related experience in addition to over three decades of experience helping industrial, energy, and government clients solve complex environmental issues. His areas of expertise include environmental review (EA, EAW, and EIS); water supply and dewatering investigations; remediation of soil and groundwater contamination and coal combustion residuals (CCRs); and permitting of large capital projects involving oil and gas wells, injection wells, mines, and power plants. Jim’s background also encompasses Phase I environmental assessments, Phase II site investigations, brownfields redevelopment, and solid-waste investigation and permitting. He also assists clients with facility compliance, due diligence, and economic alternatives analysis, and provides expert testimony in legal proceedings.

Kevin Solie, senior environmental engineer, has more than 30 years of experience in the environmental field, including extensive waste management and water quality/wastewater compliance knowledge, as well as involvement in securing permits and approvals for more than $1.5 billion in new infrastructure. In his previous position, he developed and implemented CCR Rule compliance strategies for several landfills and surface impoundments in North Dakota and Wyoming. During his career in both the public and private sectors, Kevin has established strong working relationships with federal, state, tribal, and local officials.

Related projects

Groundwater compliance assistance for CCR Rule

Barr has provided geochemistry services, groundwater-monitoring network design, data review, and statistical analysis for Heskett Station’s coal ash landfill since 2010. When the U.S. EPA administered the Coal Combustion Residuals (CCR) Rule in 2015, we developed a compliance monitoring strategy, made network improvements to meet rule requirements, and instituted statistical analysis protocol for data evaluation. Since the rule took effect, Barr’s use of statistical methods, forensics, and institutional knowledge of the site geology and historical groundwater conditions has helped the client avoid costly corrective-action measures by determining that the parameters of concern were previously observed at elevated concentrations in soil and groundwater prior to construction of the coal ash landfill.

Groundwater monitoring at Heskett Station’s coal ash landfill.

Permitting, design, and construction oversight for CCR surface impoundment

Barr assisted Minnesota Power with alternatives analyses for expansion of their coal combustion residuals (CCR) surface impoundment at Laskin Energy Center in Hoyt Lakes, Minnesota. We sited, designed, and permitted a new surface impoundment for CCR, called “Cell E,” which was configured for construction in two phases. The initial phase served Minnesota Power from approximately 2000 through 2012. The second phase, consisting of a vertical expansion of Cell E, included permitting, final design, and construction oversight, all occurring in 2010 and 2011. The vertical expansion extended the operating life of Cell E, which then ceased operations in 2015. Barr subsequently designed the Cell E closure, which occurred in 2016 through 2018. Closure monitoring continues.

CCR surface impoundment at Minnesota Power’s Laskin Energy Center.


Jim Aiken, Vice President, Senior Hydrogeologist
Jim Aiken
Vice President, Senior Hydrogeologist


Kevin Solie, Senior Environmental Engineer
Kevin Solie
Senior Environmental Engineer
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