The Oscar-nominated documentary “Waste Land,” directed by Lucy Walker, follows artist and photographer Vik Muniz as he creates his “Pictures of Garbage” series – photos of massive sculptures created with garbage culled from the world’s largest landfill, Jardim Gramacho in Rio de Janeiro. The twist? The sculptures in question are portraits depicting (and made with the help of) the scavengers living and working on Jardim Gramacho, known as “catadores.” Muniz, whose pieces frequently sell for hundreds of thousands of dollars, will auction the resulting works and give all proceeds to the catadores.

Muniz, the film reveals, was born in Rio de Janeiro and grew up in one of its impoverished neighborhoods. He emigrated to the United States as a teenager, using settlement money he received after being shot in the leg while trying to break up a fight. “Pictures of Garbage” seems as much an attempt by him to reconnect with that part of his life as it is an artistic conceit and social experiment.

Americans will no doubt be shocked and dismayed by the scenes of garbage trucks unloading into the midst of a horde of catadores, so eager to scavenge the choicest bits that they casually risk being crushed beneath the avalanche of filth. But Walker does not shy away, which makes the film’s uplifting moments starker by comparison.

If Muniz or his compatriots were concerned about exploiting the catadores, the film doesn’t spend a lot of time dwelling on it. A single scene is devoted to musing about this possibility, at the end of which Muniz concludes that if he was in the catadores’ position and was given an opportunity to make art and see the world, even knowing he would have to return to the landfill in the end, he’d still jump at the chance.

The catadores, after making art that effectively forces them to reappraise themselves, seem less willing to surrender their newfound status and self-esteem. How they confront that reality will not be revealed here.

“Waste Land” will premiere on the PBS series Independent Lens on Tuesday, April 19. Check your local listings for exact airdate.

Waste Age Web Exclusive: Read a Q&A with "Waste Land" director Lucy Walker on The Heap.

WASTE LAND Official Trailer from Almega Projects on Vimeo.