Coal, Material Handling

transition for CCR regulations

The U.S. Environmental Protection Agency is proposing a rule that would regulate coal combustion residuals for the first time, using either Subtitle C or Subtitle D of the Resource Conservation and Recovery Act. It extended the deadline for public comment from September 20 to November 19.

Either way, utilities will need to transition from unlined ash ponds to some type of lined containment. While this is new territory to energy providers, it’s not uncharted. The good news is they can learn from the experience of the solid waste industry, which had to learn to manage various waste streams and byproducts under the same set of regulations.

The draft regulations target a five-to-seven year implementation window to phase out the unlined ponds. Utilities may have ash disposal areas that are at or near capacity, or they may have areas they recently prepared for future ash disposal. How the utility transitions to lined containment can have a significant impact on system cost. Ash management infrastructure has historically been a low-cost element of the overall plant with minimal capital investment, but infrastructure and operations costs will go up as a result of the proposed regulations. The EPA estimate for converting to lined systems is between $587 million and $1.5 billion industrywide. The best way to view ash management decision making in this context is to approach it the same way one would approach a plant expansion or upgrade.

There’s no one-size fits all remedy. A likely scenario is for a utility to try to reuse some or all of a pond area. It may implement a dewatering program to prepare it for a future liner system. Upper reaches of ponds with minimal ash depth may be reclaimed to construct future lined containment. Utilities with groundwater or surface water impacts may want to approach a pond cap as a “presumptive remedy” to help abate the impact, by constructing a cap system that also meets the minimum regulatory standard for the new base liner. This is similar to a brownfield redevelopment concept.

One of the key elements of developing a successful transition plan is developing a thorough land use plan. The need to put careful thought into the land use side can’t be overstated. The way to determine best future land use involves looking at current land uses, evaluation options for future land use, preparing financial proforma for those site components and then implementing the plan.

Utilities need to examine their current pond characteristics in detail so they can come up with the best transition plan, as pond reconfiguration may have significant effects on plant operation. This entails looking at every aspect of permitting, structural stability, life expectancy, water balance, geotechnical features such as soil makeup, ground water, types of CCR, and conveyance. This short list is meant to serve as an example; when assessing their current pond structure, utilities should expect to address dozens of questions, to get a comprehensive picture of current conditions and a framework for future plans.

A second element utilities need to consider is risk analysis and tolerance. Since most utilities do not have experience decommissioning ponds, they need to determine to what standard of care it will be done, and how the decision will be made. They need to consider issues such as whether to dewater and cap in place, or move it out and reclaim the area. These decisions will be influenced by factors such as the system’s geometry (areal extent and depth of ash), land availability, and current environmental conditions.

When North Carolina began to regulate dry ash disposal, changing from allowing it to be used as structural fill on construction sites to requiring performance-based or prescriptive liner systems, industry response varied widely. Some lobbied for performance-based standards, because they knew they could handle the fate and transport modeling and demonstrate compliance using a minimal liner system and well-controlled operations such as frequently covering the ash to minimize filtration. Others were fine using prescriptive standards that mimicked the subtitle D regulations currently used for solid waste. While reactions varied in part because of physical site characteristics such as hydrogeology, they are also an indication of each utility’s risk tolerance.

As mentioned earlier in the article, EPA is currently evaluating both Subtitle C and Subtitle D regulatory options. Subtitle C requirements are more stringent than Subtitle D. For example, Subtitle D calls for corrective action to be self-implementing; Subtitle C requires corrective action to be monitored by EPA and authorized states. Subtitle C requires state and federal enforcement; Subtitle D applies enforcement through citizen suits, with states able to act as citizens. Subtitle C includes a federal requirement for permit issuance by states; Subtitle D does not. Subtitle C also includes land disposal restrictions and storage requirements that Subtitle D does not. If selected, Subtitle C would include only CCR intended for disposal in landfills or surface impoundments. It would not include CCR intended for beneficial use.

Timing may be an issue depending on which regulation is chosen. With Subtitle C, timing will vary from state to state because adoption is by the individual states. It could take from one to two years or even longer. With Subtitle D, the timeline for most provisions is six months after the final rule is promulgated. When Subtitle D became effective for the solid waste industry, the states that had adopted state regulations implement the federal Subtitle D requirements had some latitude in the implementation schedule. Some entities needed to negotiate Consent Agreements within their state to allow them to make changes after the regulation became effective.

Some utilities are weighing whether they even want to keep older coal-fired (wet process) plants open. The Charlotte Observer recently reported that Duke Energy might close seven coal-fired units within the next five years as environmental regulations intensify. While doing so is less expensive than retrofitting old units with new pollution controls, decommissioned plants with wet storage impoundments will still have to go through closure, remediation and capping. In short, they will still need a fairly comprehensive plan.

To summarize, having a well-defined transition plan, one that evaluates options such as land use and risk analysis, including in-depth analysis of the relationship between pond configuration and operations, will be critical as utilities work to meet new regulations for CCR. There are many nuances that will not be specifically defined in whatever final regulation is adopted. The way the < areas are navigated on a federal, state or local level, are also an important part of transition planning. Since regulations are a given, it’s not too early to start thinking about a plan.