That funky, ‘rotten egg’ smell overwhelming Kings Mountain? It’s from Albemarle Corp.

Kings Mountain stinks. Literally.

There’s been a lingering stench in the air in Kings Mountain for weeks now, blamed on Albemarle Corp. as the world’s largest lithium miner removes water from a dormant mine pit. The Charlotte-based company is in the process of preparing to reopen the mine.

Several residents began reporting a smell, possible “gas leaks,” all coming from the vicinity around Albemarle’s pond, the city of Kings Mountain said in a Facebook back on Dec. 6. The city assured residents the “unfamiliar odor” was natural, no natural gas leaks had been detected and crews would continue to patrol the pond.

“Smells like rotten eggs,” one person said on the post.

The Charlotte-based company has been sharing the steps it is taking to minimize the smell and public concern as the approximately 1.8 billion gallons of water is pumped into nearby Kings Creek.

In a Jan. 9 statement emailed to the Kings Mountain community, Albemarle said it is monitoring the air levels, “which are more than 10 times lower than regulatory health and safety guidelines.”

Just 12 days later, Albemarle said it had doubled the number of air monitoring systems around the pit to 10, as well as other additional steps.

“Until the mine pit can be fully dewatered later this year, intermittent odors are possible, especially in cold weather,” Albemarle said.

Why is Albemarle removing the water?

The stench is coming from the dewatering of the lake formed from 40 years of rainwater filling the dormant, open mine pit that closed in 1988.

The pit is just over 140 acres, according to Albemarle’s environmental assessment draft prepared by the U.S. Department of Energy and released Jan. 17. And it’s about 163 feet deep, The Charlotte Observer previously reported.

Albemarle, which bought the nearly 1,200-acre Cleveland County property from Rockwood Holdings in 2015, began removing the water last April in preparation to reopen the lithium mine. The mine is about 30 miles west of Charlotte off Interstate 85.

Only 2% of the world’s lithium is available in the U.S., and North Carolina is among a few places in the world where lithium mining is possible. Lithium is used in batteries to power electric vehicles, bikes and personal electronic devices.

Large green areas in white pegmatite rock called spodumene are extracted to make lithium. Albemarle’s lithium mine is expected to produce about 420,000 tons of lithium-bearing spodumene concentrate per year.

Albemarle is in the process of seeking approval to resume mining operations and expand the mine in Kings Mountain. There are over a dozen permits that need approval at the federal, state and local levels, a process the company began last summer.

There are still about eight of the expected 18 months left for moving about 2,500 gallons of water per minute out of the pit.

So why does it stink?

Seasonal temperature variations can cause changes in the surface of the mine pit water’s density. And that can displace the deeper parts of the water in the mine pit where organic material has settled, Albemarle said.

“This water contains hydrogen sulfide created from the natural decomposition of organic material, which can cause the odor,” the company said.

As the deeper water is raised to the surface, a process called “turning over,” it can result in an intermittent noticeable odor in lakes and ponds.

It has happened before, Albemarle said, such as in 2018 after several days of cold weather.

Is hydrogen sulfide dangerous?

Hydrogen sulfide is a colorless, flammable gas produced naturally by decaying organic matter and by certain industrial processes with a “rotten-egg odor,” according to the Agency for Toxic Substances and Disease Registry. The federal agency is overseen by the U.S. Department of Health and Human Services.

The federal safety guidelines are hydrogen sulfide exposure, according to the agency, are:

▪ Occupational Health and Safety Administration: limit 20 parts-per-million with a max peak of 50 ppm for 10 minutes.

▪ National Institute of Occupational Safety and Health: 10-minute ceiling limit of 10 ppm; 100 ppm is immediately dangerous to life.

Readings for hydrogen sulfide have been less than 1 part-per-million, Albemarle said, far below OSHA and National Institute of Occupational Safety and Health guidelines.

On Jan. 17, U.S. Rep. Tim Moore, R-N.C., shared on Facebook a letter he sent to the Environmental Protection Agency asking for assistance monitoring hydrogen sulfide levels, despite N.C. Department of Environmental Quality’s assurances that current air concentrations of the gas are not harmful.

“While this project is vital to our nation’s economic future, it’s equally critical to ensure rigorous air quality monitoring to safeguard public health.”

Residents say even if it’s not deemed toxic, the stench is overwhelming.

‘The smell is unbelievable, it comes into your house through the vents and it makes your stomach churn,” one person who lives a mile away from the Albemarle site said on Moore’s post.

Several people said it’s causing them headaches.

“I wake up in the middle of the night almost every night with my entire house smelling like rotten eggs and sewage that hasn’t been pumped in 50 years and a massive headache.”

What is Albemarle doing about the stink?

Along with additional air monitoring systems, here are other steps Albemarle said it is taking to mitigate the smell from dewatering the pit:

▪ Temporarily relocating a water intake to draw water from the lower levels of the mine pit where sulfide levels are higher. The water is then transferred to a water treatment facility, where sulfide is removed. As necessary, water can be returned to the mine pit to increase the amount of low-sulfide water in the top layer.

▪ Studying the use of “batch treatment,” a process where a reactant would be added to the mine pit water to help neutralize the odor-causing sulfide.

Albemarle also is considering installing buoy-like objects designed to disrupt wind movement of water to further prevent mixing upper and lower levels of water.

Residents with questions or concerns can call 704-734-2775 or email kmcommunity@albemarle.com.