Seoul (CNN) Uiseong, a picturesque South Korean farming county, was a backwater until homegrown heroes the Garlic Girls became breakout stars and curling silver medalists at last year's Pyeongchang Winter Olympics.

In recent months the spotlight has again fallen on Uiseong for a far less glorious reason: a smoldering mountain of garbage which highlights the trash crisis in the densely populated nation.

Among the rice paddies and beside the Nakdong River in the country's east, a horseshoe-shaped, 170,000-ton heap of trash is spontaneously combusting, spewing out plumes of smoke and the nose-scorching, chemical stench of burning plastic.

On a cold February morning, six workers wearing grimy overalls and gas masks clamber over the 50 feet-tall (15 meters) man-made hill, dousing the smoke with fire hoses. But as soon as one smoldering spot is extinguished, another flares up.

They have been doing this for three months -- and no end is in sight.

Park Hyun-soon, an eggplant farmer who lives next to the heap, says the fires spew ash over her greenhouses, blocking light from the plants and ruining her produce.

"The eggplants are growing gnarled," she says. "We almost never open our windows. When we leave the house, we don't smell the nature but the burning (garbage)."

The local government now issues dust masks to residents.

"My eyes hurt, my head hurts," Park says. "All the residents are suffering."

Story of a trash mountain

The Uiseong garbage pile is the largest in South Korea, according to local officials, and has a storied history.

In 2008, Kim Seok-dong, a recycling business owner, was granted a license to keep 2,000 tons of waste on the site.

But in 2016, his permit was canceled after locals began complaining that the rural spot was overrun with trash. Kim tried to fight the ban, but in 2018 a court ordered him to remove the waste.

While that struggle was raging, waste-to-energy power plant business owner Lee Won-jeong in 2017 bought the site from Kim, but kept him on as manager. Lee is based in Busan, in the south of the country, and claims he was unaware of the problems at the site.

Lee says that after the sale, Kim deposited more than 80 times the amount of garbage permitted at the site, including household waste, construction materials, and discarded polymer.

The manager of the site had a permit to dump 2,000 tons of waste, the site holds more than 80 times that now.

As the trash mountain decomposed, gas built up under the surface. In December last year, fires began to appear.

Lee says that when he learned of Kim's misconduct he fired him. Kim has since disappeared and CNN was unable to reach him for comment.

Kwon Hyun-soo, the Uiseong county environmental supervisor, says local authorities are using their own resources to tackle the trash but the flaming mountain is too big for them to resolve.

"The waste is mostly from outside of our region. It's too much for us to take care of the issue at the local level," says Kwon.

Trash crisis

There are 1.2 million tons of illegally abandoned waste across South Korea, according to the Ministry of Environment.

In theory, all waste produced in the country is handled in one of three ways: it is either recycled, processed into fuel, or incinerated. But a series of events in recent years have disrupted this system.

In 2017, a surge in smog levels prompted the government to tighten regulations on waste-to-energy plants and waste incineration facilities which were blamed for belching out polluting fumes, says Sung Nak-kuen of the Korea Waste Association.

Consequently, the number of incineration facilities fell from 611 in 2011 to 395 last year. And with the waste-to-energy plants feeling the squeeze, demand for solid recovered fuel -- non-recyclable plastic and paper burned for heat and energy -- has collapsed.

The excess waste was simply exported to China.

South Korea is among the world's worst offenders when it comes to production of plastic waste.

Exports of plastic waste from South Korea to China fell by over 90%, according to the Korea International Trade Association. Trash overflowed on the streets of Seoul as the waste management companies refused to collect it.

This environment created a black market in which brokers will offer to dispose of waste at below the market rate.

Brokers charge between $130 and $170 to dump a ton of waste in a sparsely populated part of the country, says Lee, Kim's former boss.

Not only can this be a lucrative source of income, the fines for illegal dumping are only about $3,000, Lee says.

Lee estimates that Kim pocketed upwards of $22 million this way, judging by the extra trash that was found at his site.

A new dumping ground

Since the China ban, South Korea has been using Southeast Asia as a dumping ground for much of its non-recyclable waste.

The country now exports 10 times more waste to the Philippines and almost 30 times more to Thailand than it did before Beijing's ban. But not all the waste sent abroad is disposed of legally.

A ship carrying waste from the Philippines arrives back in South Korea.

Earlier this month, a container ship docked in Pyeongtaek harbor, on the southwest coast of Seoul. On board were 51 containers of mixed waste that South Korean company Green SoKo had exported to the Philippines last year.

The company had claimed the waste was recyclable plastic, but most of it was not in fact recyclable and had been strewn over a 45,000 square meter patch (almost 500,000 square feet) of Mindanao island.

Locals discovered that the trash included household garbage, used diapers, empty cans of ham, and washing machine parts. Protests by environmental group EcoWaste Coalition put pressure on the South Korean government to take back the trash.

Container vans containing misdeclared mixed wastes from South Korea are set to be repatriated by the Bureau of Custom on January 13, 2019, from Misamis Oriental, The Philippines.

What that container ship brought back to Seoul, however, was only a fraction of the 290,000 tons of waste which South Korean Customs estimates was illegally exported in 2018.

A report released last month by the Ministry of Environment blamed the problem on the lack of affordable alternatives for disposing of solid waste.

"The cost of incineration used to be $53 per ton and now it's over $230. The waste companies cannot recycle or incinerate (affordably), so the waste is left abandoned," ministry officials said at a briefing.

The ministry has promised to track the illegal disposal of waste and deter future dumping.

'I feel shame'

But what about the trash that has already been dumped in South Korea -- such as the smoldering heap in Uiseong?

The government has said it will relax regulations on incineration to allow for disposal, but that move has not thrilled environmental groups.

Kim Mi-kyung, of Greenpeace Korea, says incineration "creates various environmental and health problems like greenhouse gases and toxic substances."

"If we expand the (use of) incinerators, the plastic use will expand with it, because it will be easy to just burn them," she says, adding that the problem needs to be tackled at the production level.

South Korea is one of the world's biggest plastic consumers.

In 2015, it consumed almost 300 pounds (132 kilograms) of plastic per capita, surpassing both the US and China at 205 and 128 pounds (93 and 58 kg), respectively, according to Euromap, an association for plastics and rubber machinery manufacturers.

A huge pile of trash in the Philippines.

While South Korea last year banned single-use plastic bags from supermarkets, Greenpeace's Kim says more must be done.

"Consumers can bear the discomfort and reduce their use of single-use cups and straws," she says. "But a greater portion of plastic production and waste is created by industry and their packaging. It's time for industry to reduce plastic."

Back in Uiseong, Park, the eggplant farmer, surveys the garbage mountain which pollutes her property.

"It has become a part of regular life," she says. "But the fact that the garbage hill is here ... I feel a bit of shame."

The government says it plans to clear 21,000 tons of trash from the burning mountain this year. What will happen to the remaining 149,000 tons is unclear.

Lee, meanwhile, says he hopes to build a plant at the site to incinerate the hill, but admits it will take 5 years to burn up all the trash.

"If I had known years ago (about the waste mountain)," Park says, raising her fist in the air in a mime of protesting, "I would have fought it."