shows a large machine for making spray, pointed over a pond and field, with mist in the air
Aerosolization enables landfill managers to spray leachate collected at the bottom of landfills over the fill area, thus evaporating pooled water. Photo courtesy Neptune Wash Solutions

By Catherine Clabby

Last week’s crossover deadline in the General Assembly clarified some of the environmental measures that legislators are expected to hash out in coming weeks.

Crossover is that legislative deadline by which bills need to complete passage through one chamber to survive the rest of the biennial session. The deadline only applies to policy bills that don’t require the state to make an appropriation, so there are plenty of bills with spending attached that haven’t been passed yet in the House or Senate.

Among the bills that environmentalists are closely tracking is HB 576. It would allow municipalities and companies operating landfills receiving municipal solid waste to without state oversight use emerging technology to ”aerosolize,” or vaporize, water that pools at the bottom of the trash pile, called leachate.

Under existing rules, landfill operators must seek approval from DEQ to use the technology. The proposed legislation would automatically approve the systems, said Department of Environmental Quality spokesman Jamie Kritzer.

Water gets contaminated inside landfills either after rainwater washes through garbage or as trash decays. Organic compounds, inorganic compounds, heavy metals, even pathogens such as bacteria and viruses have been found in leachate.

Disposing of leachate, either with water treatment equipment on site or by pumping it or trucking it to water treatment facilities, is one of the largest  single recurrent costs at landfills and it is not getting cheaper. So various companies are producing systems to evaporate the water on site as alternatives.

Diagram of "alley" used for receiving sprayed leachate. According to one explanation, the process evaporates 95 percent of liquid with each pass.
Diagram of “alley” used for receiving sprayed leachate. According to one explanation, the process evaporates 95 percent of liquid with each pass. Photo courtesy: presentation to NCGA.

What the products appear to have in common is using pressure to convert leachate to mist and blow that over the footprint of a landfill. Particles of unwelcome contaminants, if present, are supposed to fall within the footprint of a landfill.

It’s those particles that concern environmentalists, including Brooks Rainey Pearson, a lobbyist for the Southern Environmental Law Center. She spoke against the bill at a House environment committee before it passed.

“The backers of HB 576 claim that the technology is safe because toxic particles will not stay airborne, but will fall back onto the landfill,” Pearson said. “But we’ve seen no public data to confirm that.”

The House passed the bill on April 25 and referred it to the Senate, where it passed its first reading and was referred to the Rules and Operations Committee there.

Legislators asked for the change

In the 2015 budget bill, the General Assembly directed the Environmental Review Commission to “study the use of new technologies and strategies, including the use of integrated mobile aerosolization systems, to dewater leachate and other forms of wastewater for the purpose of reducing the burden and cost of disposal at the site where it is generated.”

Since then, commission members have heard state Department of Environmental Quality staff and company owners describe some options.

The technology is already gaining a foothold in the state, though with close DEQ oversight. In February 2016, the agency gave Republic Services of North Carolina permission to set up mobile aerosolization systems at landfills, as long as one or more demonstration projects showed liquid and solid emissions are “substantially” contained within lined landfills.

Independent scientific evaluations of just what type of particles these systems produce and how far they float have not been shared, Pearson said, which is one reason why continued oversight is needed.

“How far particles travel seems to have a great deal to do with specific local conditions and specific toxics, and the [bill] does not make allowance for either of those,” she said.


Michael C. Stahl, president of the North Carolina Chapter of the Solid Waste Association of North America, said landfill leachate from municipal waste landfills is not as much of an environmental threat as it once was.

Better shielding of waste from rain water, which can act like a solvent once it mixes with trash, has helped. The required sorting of hazardous waste from municipal trash streams has also had a very favorable impact.

“Leachate is not the horror story that most people have in their minds,” said Stahl, who manages Macon County’s solid waste program. “When we monitor our leachate, we’re looking at parts million and parts per billion,” he said.

The initial version of the leachate bill sponsored by Rep. Jimmy Dixon (R-Warsaw) this year closely resembled proposed legislation advanced last year by Sen. Trudy Wade (R-Greensboro). The original language this year directed DEQ to classify aerosolized leachate and wastewater that did not produce “effluent” as not requiring a permit.

After feedback from DEQ staff and others, the amended version of the measure is stricter.

The current bill language directs DEQ to approve aerosolization of leachate and wastewater within the lined borders of a landfill. It only – and explicitly –  exempts landfills accepting coal ash or sites holding wastewater from swine lagoons from automatic approval without DEQ review. The department can consider aerosolization of leachate as an acceptable method of site management for unlined landfills too.

Applicants wishing to use the technology, according to the current bill language, must provide DEQ data describing any contaminants “of concern” released aerosolization. Aerosolization that produces no discharge and is not a “significant air contamination source” would not require a permit.

In March of this year, DEQ authorized Charah, Inc to pursue a 90-day field trial using aerosolization at the Brickhaven mine structural fill project in Chatham County, one spot where Duke Energy is disposing of coal ash. The company plans to do that this summer, said Katie Hallaway of MVA Public Affairs, which represents the company.

If leachate is found outside of the lined portion of the landfill there or if contamination of surface water or soils beyond the liner is found, DEQ will require the company to stop using the system, test for contamination and, if required, dig up any sullied soils.

In addition

SB434, shepherded through the Senate by Sen. Andy Wells (R-Hickory), has already garnered notice this legislative session due to language that would repeal a rule requiring pollution-reducing riparian buffers along of the main stem of the Catawba River.

The measure, passed by the Senate on April 24, which is consistent with a drive to reduce regulations by the current legislature. It would also forbid all municipalities from requiring buffers bigger than those required by the state or federal government.

But if passed and signed into law as currently written, it would also delay readoption of the Falls Lake nutrient pollution (phosphorus and nitrogen) cleanup rules for another two years to December 2024. Falls Lake serves as a source of drinking water for about 500,000 people in Raleigh and eastern Wake County communities.


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Catherine Clabby (senior environmental reporter) is a writer and editor. A former senior editor at American Scientist magazine, Clabby won multiple awards reporting on science, medicine and higher education...

One reply on “Environmental Bills Shaping Up Post-Deadline”

  1. Leachate management is one of, if not the most significant long-term, recurring cost for landfill management. It accounts for up to 25 to 30 percent of the O&M costs. What’s more, leachate management continues well into most landfills’ post-closure period and will remain subject to evolving regulatory requirements. …
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