Some NC coal ash can safely be kept in place

Duke Energy crews remove coal ash from ponds at the Sutton power plant in Wilmington in 2017. (AP Photo)
Duke Energy crews remove coal ash from ponds at the Sutton power plant in Wilmington in 2017. (AP Photo) AP

As the State of North Carolina attempts to work out a high stakes conflict over the contentious and confusing topic of closing the remaining six coal ash basins, it seems that a little common sense and technical insight from an experienced engineer and organic farmer would be helpful. Since I am a professional engineer who is registered in North Carolina it is important to mention that this response is not a professional engineering opinion. In addition, to remain objective I do not work for Duke Energy, and/or do not provide engineering consulting or applied research services for Duke Energy.

Across the United States, coal ash basin closure technology has evolved to include a variety of practical methods like in-situ stabilization and encapsulation, partial cap-in-place surrounded by barrier walls, and selective excavation and placement in lined landfills. Meanwhile, North Carolina’s electric power utility and regulators seem to be “stuck in the past” as better, safer and more cost-effective methods are being used in other states.

Why? One reason is that Duke Energy and the Southern Environmental Law Center (SELC), and indirectly the NC Department of Environmental Quality have been locked in a contentious lawsuit that keeps experienced engineers and regulatory officials from working together to develop the best, safest and most cost effective solution for coal ash. At times partial information from well-intended, but less technical, environmental groups tends to confuse the selection of good “middle ground” remedial options.

A few insights from “boots on the ground” experience are provided:

• Groundwater models are just models, but State and Federal environmental regulations have clear requirements that must be achieved to maintain compliance.

• Regulatory agencies are the “referee” and have the responsibility to determine when environmental regulations are being followed. It is unusual and unprecedented for a regulatory agency to dictate the “means and methods” for a remedial activity.

• When a power utility is required by the NC DEQ to complete an activity to protect human health and the environment then the NC Public Utilities Act allows it to be reimbursed for actual costs. A $10 billion ash basin closure expense will be difficult to stop without changing the NC Public Utilities Act. Since SELC has been so publicly vocal and at times appeared to influence public perception and decisions being made by the NC DEQ, a few points of clarification are offered:

• The Federal CCR Rule requires that professional engineers who have experience with ash basin closure be the main technical experts responsible for developing closure plans that meet or exceed the regulations.

• Information from lawyers and the citizen groups they represent must be balanced by a concern for equally damaging impacts from unintended environmental consequences and worker safety issues that may take place during construction.

• Even though SELC is a non-profit corporation, over the past five years it has become a big law firm with an aggressive business model for growth. Are the opinions from SELC really necessary to protect groundwater, and in the best interest of all North Carolina residents?

Each coal ash basin, and the surrounding geological setting is different. A “one size fits all approach” can be both costly and have unintended environmental consequence. Complete excavation of deeper and more challenging coal ash basins can tend to spread or release more contamination when the ash is exposed to oxygen and large volumes of stormwater runoff during construction.

From my perspective as a professional engineer working full time with coal ash basin closures nationwide, and as a farmer working with sustainable agriculture and environmental groups, a few key points are offered:

• Consider creating legally protected “stakeholder working groups” for each of remaining coal ash basin sites. These groups would include NC DEQ and Duke Energy representatives, but also representatives from the local riverkeeper and citizen groups, and construction and engineering professionals.

• Recognize that even though coal ash has some small amounts of toxic elements, it is primarily a pozzolanic material that can be easily and safely be stabilized long-term with lime and cement.

• Consider the proven encapsulation and hybrid remediation technologies that have been used on numerous industrial and hazardous waste sites in North Carolina and across the United States.

Chris Hardin is a North Carolina registered professional engineer, with over 25 years experience in environmental remediation, coal ash basin closure, organic farming and sustainable development. He can be contacted at chardin@energyenviro.org