FROM the midst of one of Mexico’s largest rubbish dumps, a sea of stinking waste eight miles long and one mile wide, arises the clear, sweet sound of voices singing Mass.

This improbable service takes place once a week. A few dozen ragged worshippers break off from their scavenging to huddle around the “altar” — a folding metal table bearing a cross made from waste metal — that Padre Roberto Guevara sets up amid the garbage. The 30-minute ceremony offers them the briefest respite from the misery of their lives.

All around rumble dumper lorries, horses and carts laden with refuse and men carrying giant bags of rubbish, like leafcutter ants, to sell for recycling. The activity never stops, and the priest’s voice is sometimes drowned out by the snarl of wild dogs fighting for scraps.

Father Guevara, a 70-year-old Jesuit, has been preaching to this lost flock for 21 years, arriving at the dump by Jeep every Wednesday morning. He has established a charity that helps 400 children living in or around the dump to go to school, eat three square meals a day and escape beatings from their parents. He provides food and rudimentary medical assistance for the rubbish pickers — the pepenadores — and they love him for it.

“Having him here we don’t feel so alone,” says Anastasio Tavira, 47, who can neither read nor write and has been here for 24 years, living in a shack knocked together from scraps of wood and plastic.

“Life here is hard,” he adds as he pulls up a soiled block of polystyrene foam to act as a pew for himself and several wizened old women. “Sometimes we don’t even make enough money to afford a few beans. It’s hard. Your fingers get cut from rooting through the rubbish. It’s horrible here, really horrible.”

Father Guevara’s reward is to have won acceptance by a feral subculture so off-limits that it has, over decades of isolation, developed its own feudal system that keeps thousands welded together by fear, solidarity and despair.

Life for the dump’s hundreds of pepenadores is almost unbearably hard, picking up rubbish for 12 hours a day and earning as little as $3. But they rely on their rubbish as a farmer relies on his crops, and have no choice. They have nowhere else to go, and their lives are tightly controlled by the dump’s Mafia-style clans.

“The first time I came to the dump to give Mass, I was a Jesuit full of revolutionary fire and into social justice,” Father Guevara tells The Times. “It occurred to me to ask them how much they earned. I saw that after 12 or 14 hours’ work they didn’t even make the minimum wage for eight hours, so I told them about the federal law.”

He advised the pepenadores to ask their leaders for a living wage, little realising how ruthlessly the shadowy chiefs run their fiefdoms. Pepenadores are not allowed to sell their recyclable plastic bottles, cardboard and metals to anyone but designated intermediaries who drive on to the dump and sell the refuse at a higher price in nearby Mexico City. The priest was bluntly ordered not to return.

That changed shortly afterwards, when a devastating earthquake killed 50,000 people in Mexico City in 1985. As body parts started to show up in the debris arriving at the dump, the priest was invited back to bless them, but was told that his sermons were being watched for any signs of activism.

Since then, in order to continue his work, Father Guevara has had to come to terms with the dump’s criminal undercurrents, the exploitation of its people by their leaders, and even the occasional murder of one gang leader by a rival. “These people are born and then live with the criminal element and exploitation. But I knew that I couldn’t change that system. So I thought I have to respect it,” he says.

What inspires him to keep going is the same spirit that keeps the pepenadores alive. “I see them as people who are drowning — drowning victims of a society that has pushed them aside. They will clutch hold of anything to keep from going under, and that gives me a lot of strength to keep going through my own hard times.”

They also support one another. “There is a cycle of exploitation, but the only thing they have is each other. They have unity,” Father Guevara explains after the Mass. “When a cart driver’s horse dies, he holds a party and everyone eats meat” No one steals from another person’s stash of plastic bottles. Perpetrators of serious crimes have to leave or risk having their throats cut.

But workers at the charity school say that child abuse and domestic violence are still rife in this unforgiving, tight-lipped society. “If you treat people like animals, they’ll treat each other like animals,” the priest says, as affection-starved infants cling to his hands and legs.

The school gives the kids a glimmer of hope, but for the adults who till the rubbish there is only one thing to pray for at weekly Mass: more trash.

“There are many people here,” Señor Tavira says. “We want the work to continue, we want them to keep on giving us the garbage. That’s what we ask God for when we pray.”

LEFTOVERS

• Europeans produce 1.84 billion tonnes of waste a year, or 3.5 tonnes per person, roughly the weight of an Asian elephant
• The world manufactures between five and six trillion cigarettes annually. The butts from these would fill the Millennium Dome twice over
• Some rubbish dumps hide sinister secrets. In the past month, 28 human skulls have been found on rubbish dumps in Haiti
• The world’s rubbish dumps gain more than a million plastic bags every minute. Annually that is enough plastic to shrink-wrap Britain
• Each year almost 10 million tonnes of waste in Britain — far more than the total mass of every man, woman and child in the country — comes from packaging

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