(CNN) -- On the outskirts of Rio de Janeiro, nestled along Guanabara Bay and within sight of the iconic Christ the Redeemer statue, one of the world's largest open-air landfills has closed after more than three decades of operation. The landfill, known as Jardim Gramacho or Gramacho Gardens, is piled almost 300 feet high across 14 million square feet -- the equivalent of 244 American football fields. It is the largest landfill in Brazil and all of South America. Built in the late 1970s, it received close to 8,000 tons of trash daily, 70% of all the trash in the Rio metro area.
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A Rio de Janeiro dump, the largest in South America, is closing after three decades
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Drug-ridden slums, informal economy grew up around Jardim Gramacho
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Thousands of scavengers, called catadores, made their living off recycling trash there
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The government is promising to retrain workers, improve slums, turn land into park
Jardim Gramacho
Jardim Gramacho
At the turn of the century, complaints arose that Guanabara Bay was not safe for bathing because of contaminants leaching from @placeholder.
Jardim Gramacho
Jardim Gramacho
In addition, medical waste from all the hospitals in the area was dumped at @placeholder.
Brazil
The workers can seek treatment at state hospitals through @placeholder's precarious public health system.