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SANTA MILAGROSA, Philippines — Brian Mullaton is 13 years old and makes his living by diving into deep, muddy holes.
He works on a floating wooden platform in shallow Mambulao Bay in what is one of the world's most dangerous professions: compressor mining.
On a typical day, he makes the equivalent of $5.
"Sometimes, I am scared to go down because of the possibility it will collapse," said Brian, the fourth of nine children in his family. "But I like the job because I get money. I give the money to my parents for food."
Compressor mining originated as far back as the mid-1990s here in Camarines Norte, an impoverished coastal province about 200 miles southeast of Manila.
Divers dig down as much as 60 feet while breathing through a tube connected to a makeshift compressor, which often is made from a San Miguel beer keg. They dig in rice paddies, rivers and bays and stay underground for hours at a time. Their job is to fill bucket after bucket with soil for a fellow miner to haul to the surface. Some wear a snorkel mask, but many don't; they just keep their eyes shut.
The job is hazardous, the returns are paltry and they say their work is illegal. But that doesn't stop the miners -- mostly adults and some children -- from diving into the mud to find gold.
"We have no choice," said Rafael Ramorez, 16, who dropped out of high school during his freshman year to start working as a miner. "There is no other opportunity. There is no other job."
Rafael spoke as his cousin, Jonathon Ramorez, 12, stood waist deep in the murky bay with a wide wooden pan he uses to separate gold from sediment. In his teeth, he held a plastic bag containing a small lump of mercury and gold, the product of the crew's work for the day.
Jonathon, Rafael and Brian are among the 1 million children worldwide who work in the hazardous occupation of mining, according to an estimate by the International Labor Organization, an agency of the United Nations.
Compressor mining was banned in the Philippines under a 2012 executive order. The crews also operate outside the law by employing children and using highly toxic mercury. At Mambulao Bay, miners say they stay in business by paying police agencies the equivalent of $11 a month for each worker. Local officials say the miners are issued permits.
Chief inspector Juancho Ibis, the town police commander, said no miners have brought charges of bribery against the police.
More than 400 miners work from 40 rafts of wood and bamboo anchored on the bay near the village of Santa Milagrosa. Typhoon Haiyan, which ripped across the Philippines in November and left thousands dead, had little effect on the miners here. The center of the storm passed more than 260 miles to the south, interrupting operations for only a day.
Most of the rafts have a blue plastic tarp stretched overhead to provide shade from the harsh tropical sun, giving the place the look of a floating encampment. The workers get around in wooden canoes, which double as tubs for breaking up the sediment.
Boys and girls as young as 10 work alongside adults in crews of about a dozen people. The children usually do the less strenuous jobs, including panning for gold while standing for hours in the filthy water.
The $5 the miners make on a typical day is more than they could earn at other unskilled jobs in the impoverished region -- if they could find a job.
Compressor mining was inspired by Filipino fishermen who use compressors to breathe underwater while catching reef fish. The beer-keg compressor is connected to a small motor designed for pumping water from wells. The miners loop the air hose around their shoulders and hold the end in their teeth.
At the surface, the tunnel opening is small -- barely 3 feet square. As soon as the divers descend into the hole, it is impossible to see. Operating by feel, they shovel dirt into a rice bag that serves as a bucket.
Once the miners reach a layer of dirt where there might be gold, they dig sideways, heightening the danger of collapse. A fellow miner at the surface occasionally scoops water into the hole to equalize the pressure as the soil is removed.
Compressor mining poses a range of health risks, especially to children who dive.
When a diver is underwater, nitrogen bubbles can form in the bloodstream and travel to the brain and lungs, causing many small patches of damage. The problem can be exacerbated when the compressor motor unexpectedly stops and the diver rushes to the surface for air.
Diesel fumes, carbon monoxide and other pollutants can enter the hose and contaminate the air the divers breathe, sometimes with deadly effect. Miners on the bay say the man who thought up compressor mining died from inhaling oil through his hose.
In addition, the divers can suffer skin infections or maladies such as leptospirosis from being immersed in the dirty water, which often is tainted with animal waste and teeming with bacteria, said Julie Hall, World Health Organization representative to the Philippines.
"For somebody to be spending a lot of time breathing poor-quality air, under pressure, under the water, and exposed to all of these bacteria and other bugs in that dirty water, this clearly poses a significant health risk," Hall said during an interview at her Manila office. "And particularly for young people, if they are doing this repeatedly, it is likely to affect their development."
Compounding the risk to miners, the mercury they use to extract gold dust from the sediment is highly toxic and is known to cause tremors, memory loss and brain damage, among other symptoms.
"You can't reverse mercury poisoning," said Richard Gutierrez, executive director of Ban Toxics, an environmental group seeking to end mercury use in the Philippines. "Brain cells are destroyed and can't be replaced. You can't reverse the nerve damage."
Of all the hazards, divers say their greatest fear is that the tunnel will cave in while they are deep inside. Miners say they know of two men who were crushed that way under the bay.
The biggest disaster occurred last November in Paracale, a coastal town about 10 miles east of Mambulao Bay where miners had dug about 100 mineshafts on the beach and offshore. Some of the tunnels collapsed, and seawater rushed in. Three bodies were recovered, but some accounts suggest that the toll was significantly higher.
An investigation by the federal Mines and Geosciences Bureau concluded that a miner working illegally had used explosives and caused the tunnel collapse. The deaths drew national attention, and authorities banned all mining at Paracale. But compressor mining continues elsewhere.
About five miles inland from central Paracale, in the small farming village of Tawig, an extended family group of 16 miners has set up operations in the waterlogged soil between a rice paddy and the Bacung River. The crew includes cousins Edlyn Ortiz, 12, and Elias Delima, 15.
The group has been mining for several days in a grove of nipa, a small, sturdy palm common along riverbanks. The ground is pockmarked with holes brimming with brown water. They look like mud puddles but are as much as 40 feet deep.
Two divers send up buckets of dirt. Family members shovel the dirt into a tub, break it up with their feet, run it through a sluice box and pan the sediment that's left to extract gold dust.
Five-year-old Ernie Delima plays in the mud and helps by hauling water and moving dirt.
Older brother Elias, who dropped out of school in the fourth grade to work in the family business, said he occasionally takes the hose in his teeth and dives underground.
"I just want to go in and help," he said.
Still, he said, diving into the muddy tunnel is unnerving.
"I feel scared," he said. "I am afraid because maybe the tunnel will collapse. It is very hard to breathe."
The diver gets a double share of the earnings, and Elias said he once earned the equivalent of about $23 in a day. But he concedes that he would be happier doing something else.
"I'd like to find another job," he said.
Dindo Leche, 20, who married into the family of miners, said he began diving at 14.
"I had no choice," he said. "We needed to support the family."
He was afraid when he first started diving, but not anymore. His longest stay underground is six hours.
"I don't feel anything inside the hole, just cold," he said, then added: "I feel a little afraid that it will collapse. A lot of the time, the soil collapses."
At the end of the day, Leche takes the gold-laden sediment they have all collected, mixes it with mercury and swirls it around in a wide, wooden pan. Squeezing out the excess mercury through a piece of nylon, he ends up with a lump of metal smaller than a wad of used chewing gum. Later, he will burn it with a blowtorch to vaporize the mercury.
It is one last hazard the family faces in a long day of mining.
Richard C. Paddock is contributing editor at the Center for Investigative Reporting. Journalists Larry C. Price and Sol Vanzi, in Manila, contributed to this report, which first appeared on the Center for Investigative Reporting's website. Price is documenting child labor in developing countries as part of a long-term project funded by grants from the Pulitzer Center on Crisis Reporting in Washington, D.C. This story was produced in collaboration with the Pulitzer Center and The Philadelphia Inquirer.