A toxic dumping ground festers on the border Heaps of old cars, junk and industrial waste leave a hazardous legacy near the U.S.-Mexico border. Mexicali's dump sites pose a serious health threat.

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On the outskirts of Mexicali, where cattle graze and tractors roll across the farmland, a sooty building belches out clouds of smoke.

Twisted scraps of metal and the smashed skeletons of old cars sit in piles next to the hulking plant, where machinery hums loudly, punctuated by the booming sounds of metal striking metal.

Outside the plant’s walls and across a narrow dirt road, Blanca Ramírez lives in the same farmhouse where she grew up. She remembers when she was a kid, before the steel mill was built, the land across the road was an alfalfa field and the air was clean.

Now smoke pours out of the plant at all hours, floating over a row of houses and across the fields.

“The pollution has gradually increased, because we didn’t used to see as much as we see now,” Ramírez said, standing on the road beside the plant. “It’s terrible.”

The Grupo Simec steel mill is a huge recycling facility. It devours metal scraps and the chassis of old cars, which arrive on trucks from junkyards where they have been stripped of parts. The metal goes in dirty, covered with paint and rust, and is melted down along with iron ore and carbon coke, then emerges clean as pieces of steel rebar for construction, stacked in bundles on trailers.

A heap of scrap metal is piled against a wall at the Grupo Simec steel mill near Mexicali. Zoe Meyers/Desert Sun

The smelting process separates impurities from the molten iron and leaves behind waste: heaps of grayish black slag, which in other places has been found to contain calcium, silicon, iron, chromium, manganese, lead and other metals and pollutants.

Some of the slag is piled inside the compound’s walls, looking like rolling hills. Other mounds of slag have been dumped outside the walls, on the opposite side of the plant from Ramírez’s home, forming a flattened heap beside a trash-strewn ditch and a dry field where no crops are growing.

Mexicali and surrounding areas along the border have become a dumping ground for all sorts of junk, from old appliances to e-waste to discarded tires, some of which arrives from the United States. There’s money to be made here from some types of junk. Old cars can be dismantled for reusable parts. Old iron and copper can be resold or melted down to make new material. And a whole host of businesses, both large and small, legal and illegal, focus on taking in discarded items and recycling anything of value.

But the problem with Mexicali’s recycling businesses isn’t what gets recycled. It’s the stuff that goes up in the air and the leftover waste that is cast aside in the process.

All around Mexicali, vacant lots are littered with trash ranging from household garbage to shattered pieces of old computers. In backyards, heaps of plastic and cardboard are collected by unlicensed recyclers. Along the city’s streets, blazing piles of tires and electrical cables send columns of black smoke billowing into the air.

In the junkyards, old cars are lined up row after row, baking in the sun and leaking oil onto the ground. The cars are cannibalized for their parts, and the battered remnants are trucked to the steel mill southeast of the city, where they are dumped along with metal scraps including pieces of old appliances, rusty iron cables and a mishmash of discarded railings, gates, racks and barrels, among other things. Atop a pile of junk that towered over the plant’s walls, a tricycle with pink tires protruded from the jumble of metal.

Elsewhere in Mexicali, where maquiladoras have proliferated to manufacture products for export, many dumps, scrapyards and recycling businesses have sprung up to take in waste from both Mexico and the United States. While some of the businesses have licenses and say they are complying with environmental rules, many others are operating illegally.

The top environmental official in the state of Baja California has acknowledged that despite efforts to shut down illegal dumps, many remain and the problem is still largely out of control.

'Nothing of that is left'

Blanca Ramírez stands outside the Grupo Simec steel mill near Mexicali. She says the plant has been spewing more smoke lately. Zoe Meyers/The Desert Sun

When Blanca Ramírez was growing up here, her father farmed cotton, alfalfa and wheat. She and her five sisters and two brothers helped pick cotton. They bathed in the canals and took walks through the fields.

Back in the 1970s, they didn’t have electricity or air conditioning. On hot summer nights, they climbed a ladder to the roof and slept out in the fresh air under the stars.

Looking through family photos, Ramírez found one showing one of her sisters in a red dress posing in a green field, and another of her family standing on a dirt road.

“Without pollution, the air looks good, the sky clear. And now nothing of that is left,” she said. “Everything’s changed.”

Watch: A steel mill fouls the air in the Mexicali Valley Blanca Ramirez holds onto farm despite deadly pollution. Cities on the U.S.-Mexico border suffer in a toxic haze. The pollution is making people sick and cutting lives short, yet polluters face little enforcement. Zoë Meyers, The Desert Sun

In the early 1990s, a neighbor sold his farmland and the steel mill was built on top of it.

The plant began operating in 1993. It was initially named Compañía Siderúrgica de California, and its walls bear the giant initials CSC.

Ramírez said her father, Federico, soon began noticing that the soot was harming his crops and leaving stunted patches of yellow vegetation.

“We saw that it didn’t let the plant grow because the dust that fell from there was heavy,” she said. “It’s difficult for the plant to develop, and so it doesn’t develop. It dies.”

When her father complained about the damage to his wheat, the steel mill paid him for his losses. Ramírez doesn’t know exactly how much, but it was a small sum and the only time he received money from the company.

Blanca Ramírez’s father, Federico, poses with a cow on his farm near where the steel mill now stands. Courtesy of Blanca Ramírez

Ramírez’s 80-year-old mother, Raquel Hernández Rodríguez, remembered that after her husband’s complaints, the company sent a man who placed an air monitor in their yard. The next day, he came back to pick it up. She remembered him saying, “It’s clean, ma’am.”

They never heard anything more from the company. They weren’t satisfied with the response, but they didn’t see anything more they could do.

Several years ago, Ramírez’s father died of prostate cancer. Two of her aunts also died of cancer.

Ramírez is unsure what’s in the smoke from the incinerated junk or how it might be affecting people’s health. But she worries it must be harmful.

Meanwhile, Grupo Simec’s business has been growing.

The company is a subsidiary of Mexico-based steel company Industrias CH, led by Chairman Rufino Vigil González, a Mexican billionaire. Grupo Simec says on its website that it has 19 plants for steel production and processing, including 11 in Mexico, seven in the United States and one in Canada.

A representative of Grupo Simec didn’t respond to a request for an interview but said in an email that official information about the publicly traded company is available online.

The Mexicali “mini-mill” is supplied by three scrap-metal processing plants, the company says on its website, and it produces rebar as well as other shapes, including “angles, rounds, squares, flat bars.”

In the United States, the Environmental Protection Agency says emissions from steel mini-mills typically include metal dusts, made up of iron, zinc, chromium, nickel, lead, cadmium, and other metals, as well as gases including carbon dioxide and nitrogen oxides. The agency says emissions from the plants’ furnaces in the U.S. are generally captured and routed to baghouses to control levels of particle pollution.

Grupo Simec says it “has made an ongoing commitment to environmental protection and every year we make significant investments to maintain all the equipment in operation at our production plants in good working order.” The company says all of its plants comply with environmental regulations.

Smoke floats into the air at the Grupo Simec steel mill, which is flanked by several homes and farmland south of Mexicali. Zoe Meyers/The Desert Sun

The steel mill is regulated by Mexico’s federal government and was fined for violations three years ago. But government regulators have allowed it to continue operating.

The company, which is listed in Mexican government documents as Arrendadora Simec, S.A. de C.V., has reported releasing a list of regulated pollutants into the air. A federal pollution database shows that between 2011 and 2014, the company reported emissions of air pollutants including carbon dioxide, benzene, arsenic, mercury, nickel, lead, formaldehyde, chromium and cadmium.

When the plant spews out thick smoke, Ramírez said, it smells like plastic or metal — “something heavy” in the air.

If she hangs clothes out to dry in the sun, she said, the fabric will absorb that dirty smell. So she stopped hanging the family’s clothes outside.

In the mornings, she said, the smoke hangs over the farmlands like fog.

“We can’t open the windows of our house anymore,” she said. “It’s alarming.”

Dumps everywhere

Smoke billows from burning trash next to the Grupo Simec steel mill in the countryside southeast of Mexicali. ZOE MEYERS/THE DESERT SUN

Mexicali’s many recycling businesses, scrapyards and dump sites create problems that go beyond aesthetics.

Circuit boards in discarded cellphones and electronics, for example, include toxic pollutants such as arsenic, cadmium, lead and mercury. Acid from old car batteries can leak into the soil. Whenever junk is filled with hazardous chemicals, the toxins can leach into the soil and pollute the groundwater as well as water running in ditches.

For years, government officials on both sides of the border have recognized that the widespread unregulated dumping in Mexicali represents a potential hazard.

In a 2012 report, consultants working for the Border Environment Cooperation Commission studied how to improve the city’s deficient garbage-collection system and made a list of suggestions. They said Mexicali’s ditches and drains are badly polluted “due to the large volume of solid wastes,” and that polluted water from dumps is flowing into the sewage-filled New River, which crosses the border and continues past a neighborhood in Calexico.

The report said the trash dumped along ditches and canals has included discarded mattresses, household garbage and other debris, and that the “lack of control” adds to the pollution problems. The authors suggested, among other things, cleaning up one of the drains that feeds the New River.

The U.S. Environmental Protection Agency and the California EPA have since provided funds for cleanups in the city’s ditches and drains. The work has involved pulling out tires, refrigerators, furniture and other debris.

In 2016, U.S. and California officials announced $300,000 in state and federal grants to help with cleanups and pay for an environmental education campaign to raise awareness about the problem of illegal dumps.

Those projects have had limited success. Widespread dumping has continued, and efforts by Mexico’s chronically underfunded environmental agencies to crack down haven’t come close to making a dent.

Last year, Baja California’s Environmental Protection Department said it shut down 29 illegal dump sites covering a total of 250 acres.

“Right now, the problem we see most often is illegal dumps,” said Thelma Castañeda Custodia, the agency’s secretary.

The dumping often happens at night on vacant lots, she said, and even if the landowners don’t know about it, they are still held responsible.

“We close down the property, the plot, and then we try to find out who the owner is,” Castañeda said. Often, her staff orders the owner to fence off the land and keep it clean.

She said most of the complaints the agency receives aren’t related to established businesses, but rather to illegal operations such as junkyards without permits.

“There are many people who engage in providing service to some companies, picking up their waste, but they’re not registered with us,” Castañeda said.

She said she doesn’t know how many recyclers and junkyards are doing business illegally, but she guesses for every one that’s legal, there may be three others without permits.

In many cases, the illegal waste-handlers run small operations, sometimes using their own home as a dump.

What’s dangerous about these illicit businesses, Castañeda said, is that when people are storing old car batteries or burning up cables to salvage copper, “they don’t have any idea how polluting it can be.”

Baja California’s Environmental Protection Department provided dozens of inspection documents in response to a request from The Desert Sun. Those documents from 2016 and 2017 included 35 inspections that led to fines, which ranged from the equivalent of $750 to about $6,500. Twelve of those cases involved waste disposal or recycling businesses.

The agency has just four full-time inspectors to enforce environmental rules in Mexicali, and the documents show they are spending a significant share of their time examining waste businesses and recyclers.

“If we put together all of that waste, I think we’d see the magnitude of the problem.” Thelma Castañeda Custodia, Secretary of Baja California’s Environmental Protection Department “If we put together all of that waste, I think we’d see the magnitude of the problem.” Thelma Castañeda Custodia, Secretary of Baja California’s Environmental Protection Department “If we put together all of that waste, I think we’d see the magnitude of the problem.” Thelma Castañeda Custodia, Secretary of Baja California’s Environmental Protection Department “If we put together all of that waste, I think we’d see the magnitude of the problem.” Thelma Castañeda Custodia, Secretary of Baja California’s Environmental Protection Department

One of the problems along the border, Castañeda said, is the large quantity of used goods that arrive on trucks from the U.S. and come through customs as secondhand items.

“Electronics, tires, clothes, a ton of things pass through as goods that are still usable, but very quickly they become waste, rubbish,” Castañeda said. “That’s what has us, especially on the border, stuck with a problem now of accumulating tires and other types of waste — electronics and other types of waste that people simply don’t know where they can dispose of it.”

She said one of the state government’s goals is to help more legitimate waste recyclers start legal businesses, so that the city can recycle more of the stuff that ends up in dumps.

As it stands, people in Mexicali can drop off alkaline batteries for disposal, but they don’t have anywhere to take e-waste, for example, so old electronics end up mixed in with other junk.

“For us, I think waste is the most difficult part” of environmental oversight, Castañeda said. She acknowledged that the problem has been growing as junk has accumulated in illegal dumps.

“If we put together all of that waste, I think we’d see the magnitude of the problem,” Castañeda said. “There’s a lot — a lot, a lot, a lot — that remains to be done.”

Still, she defended her agency’s performance and said it has made progress by shutting down some dumps.

As for Mexicali’s maquiladoras, Castañeda said she thinks her agency’s oversight is sufficient.

Industrial waste

Griselda Núñez Ramos is one of dozens of "pepenadores," or trash pickers, who live and work at a dump south of Mexicali. Zoe Meyers/The Desert Sun

As state officials explain it, their system of enforcement often involves visual inspections of factories and checks of their registration documents. It isn’t clear whether that approach enables them to detect and deter improper waste dumping by factories.

Mexico’s government allows foreign-owned maquiladoras to import raw materials and machinery tax-free as long as they export the finished products.

While operating under that regimen, the companies need to track the raw materials they bring across the border, the finished products they export, and where they send their waste, said Roberto Durazo, director of business development for the Mexican company IVEMSA. His firm assists foreign companies and provides “shelter” services, acting as their legal representative in the country.

“All the scrap, the company has to keep very strict controls,” Durazo said. “If they are bringing in metal and they have some metal scrap, they cannot just throw it somewhere.”

Under Mexican law, waste that’s classified as requiring “special handling” falls under state authority. That includes items like metal scraps and plastic.

The federal government regulates hazardous waste, which includes any waste that is covered in oil or contaminated with chemicals, among other things.

In general, the maquiladoras are supposed to export any hazardous waste back to the country of origin, in many cases to the United States. But León Felipe Ruiz González, operations director for the consulting company Consorcio Ambiental, said there are also “legal caveats” that allow for some hazardous waste to be disposed of in Mexico.

He didn’t elaborate on those caveats. However, government records show some companies are disposing of hazardous waste in Mexico.

Documents from the federal Ministry of Environment and Natural Resources list companies that are authorized to handle hazardous waste. In Mexicali, they include 19 companies authorized to transport hazardous waste, four approved recyclers of hazardous waste and 11 companies that store hazardous waste.

The documents show those companies receive things including lead-tainted waste from electronics welding, flammable solvents, pesticides, auto waste including lead and acid, corrosive substances, paint, contaminated soil, asbestos, sludge left over from chrome-plating, waste containing cyanide, lead-tainted slag from furnaces and other toxic chemicals.

When a company opens a factory in Mexico, it’s required to prepare an environmental study and provide details about the waste it will generate and how it will dispose of the waste.

“By law, all the companies that have hazardous materials as scrap, they have to build a special room in the factory, that the only purpose of that room is to hold hazardous materials,” Durazo said. The hazardous waste will be stored there until it’s picked up by a certified company and taken away.

“That’s how it should work,” Durazo said. “I cannot assume that all the companies do it like that, but they should be doing it like that.”

Durazo’s company has about two dozen maquiladoras as clients, and he said he doesn’t remember any of them having problems with environmental regulations or fines in recent years.

Mexico’s federal database of pollution emissions includes not only companies’ self-reported air emissions, but also discharges of wastewater and waste that affects soil. The database shows that between 2005 and 2016, some factories and power plants in Mexicali reported contaminating soil with pollutants including arsenic, cadmium, cyanide, chromium, mercury, nickel and lead.

Companies that reported lead discharges affecting the soil included Masterwork Electronics, which makes circuit boards, lamp manufacturer Eaton, electronics manufacturer Coto Technology, truck maker Kenworth, metal foundry Maquiladora San Diego and electronics company Panasonic, among others.

Because the information is self-reported by companies, the releases of pollutants generally appear to be at levels permitted under Mexican regulations.

The Grupo Simec steel mill, despite the large slag heaps both inside and outside its walls, didn’t appear to have reported any pollution of the soil. Yet when water soaks into slag heaps at steel mills, researchers have found that metals, including chromium and manganese, can leach out. Steel slag generally produces highly alkaline drainage, which can taint the groundwater and nearby waterways.

When a company lists a release of a pollutant under “soil,” it may refer to contaminating soil while storing waste on the ground, said Alfonso Blancafort Camarena, the top official of Mexico’s Ministry of Environment and Natural Resources in Baja California.

“If it’s within the permitted benchmarks, well then, it’s within compliance,” Blancafort said. And if the levels exceed the permitted thresholds or pose a threat of polluting water, he said, federal regulators will act.

The records in the database don’t give specifics or list regulatory limits, and the amounts of pollutants reported varied widely in the data.

It’s not clear how often inspections by federal regulators lead to violations or fines. The Desert Sun requested inspection records from the Federal Attorney for Environmental Protection but was unable to obtain the documents.

Teenagers swim in the Pacífico Canal in the Mexicali Valley. Their parents work as "pepenadores," or waste pickers, in a nearby dump. Zoe Meyers/The Desert Sun

As for the many illegal dumps in Mexicali, Blancafort said the situation is “bringing us into a crisis” and the city needs to improve its system of collecting household garbage.

Some of the trash that’s dumped around canals and lagoons is still ending up in the New River, and Blancafort said the uncontrolled dumping poses risks, because while the authorities haven’t discovered any toxic waste sites in years, it’s possible that some people are quietly collecting hazardous chemicals.

“That’s our concern, that at some point that would become a dump site for toxic waste,” Blancafort said. “I don’t think it’s happening as it did some years back, but because of the lack of control of some sites, it could eventually happen. I think it’s a risk.”

At an old landfill in the desert south of Mexicali, people live in makeshift shacks made of wood scraps, cardboard, blankets and tattered plastic sheets. They earn barely enough to survive collecting recyclables such as plastic bottles and turning them in for cash.

Yenny Gutiérrez Moreno, one of the trash pickers, said she heard that years ago, before she started doing this work, people at the landfill had seen a truck arrive carrying drums filled with toxic chemicals, and they angrily prevented it from unloading the cargo.

“We control the business,” said Amado Cruz, a man with a black-and-gray beard who sat shirtless next to his shack, smoking a cigarette.

“They aren’t supposed to dump toxic materials here. It’s only household trash, businesses’ trash, not industrial,” Cruz said.

Asked what would happen if a truck arrives carrying industrial waste, he said: “If one comes, they send them to bury it up there.”

He motioned uphill to the sloping desert at the foot of the mountains.

“It’s not allowed here,” he said.

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Legal and illegal recyclers

A worker at Green America Recycling & Recovery takes a handful of wires to a grinding machine to demonstrate how the wires are chopped up and recycled. Zoe Meyers/The Desert Sun

One afternoon in April, a column of black smoke rose over a busy avenue in Mexicali. The cloud was billowing from a house tucked behind a row of factories on an unpaved dirt road.

Police and firefighters arrived with lights flashing.

Neighbors stood on the road, watching the tower of smoke expand and drift with the breeze above the power lines. Angélica Luque said the man down the road had collected mounds of cardboard boxes and plastic next to his house, and it all caught fire. Some of the smoke was spewing from burning tires.

“But if the authorities don’t do anything, what can I do? I can’t do anything.” Angelica Luque “But if the authorities don’t do anything, what can I do? I can’t do anything.” Angelica Luque “But if the authorities don’t do anything, what can I do? I can’t do anything.” Angelica Luque “But if the authorities don’t do anything, what can I do? I can’t do anything.” Angelica Luque

“They had already come and warned him to get rid of it all. But he didn’t pay attention,” Luque said, standing with arms crossed under a tree. She said the smoke must be harming people’s health, including her children.

“But if the authorities don’t do anything, what can I do?” she said. “I can’t do anything.”

Just as some people try to profit from illegal dumps in their yards, other businesspeople are trying to go the legal route.

One of them is Horacio Palma, an industrial engineer who once worked for maquiladoras and specialized in making plastic items such as milk bottles and medical oxygen masks. Now he manages Green America Recycling & Recovery, a Mexican company that receives waste from maquiladoras.

When he signs up a new client, he offers a “complete service” that includes accepting any kind of waste, whether it’s regular garbage, waste that’s classified as requiring “special handling,” hazardous waste or recyclables.

The company charges companies for disposing of their waste. Scraps of non-recyclable plastic or wood, for example, are taken to a special landfill operated by one of Green America’s partners.

When a maquiladora has waste that’s contaminated with oil or chemicals, it’s considered hazardous waste. In those cases, Palma said Green America works with another company, which ships the material to a disposal facility across the border in Yuma, Arizona.

“It’s illegal, but they do it. That’s what we try to avoid, those big burns.” Horacio Palma “It’s illegal, but they do it. That’s what we try to avoid, those big burns.” Horacio Palma “It’s illegal, but they do it. That’s what we try to avoid, those big burns.” Horacio Palma “It’s illegal, but they do it. That’s what we try to avoid, those big burns.” Horacio Palma

Palma said all of the waste his company receives goes to a licensed facility.

In the case of valuable recyclables such as bundles of copper wires, his company pays the factories for the wires and grinds them up in a machine to extract the metal.

Standing in a hangar-like warehouse, Palma said he views this part of the work as especially important because when wires aren’t properly recycled, they often end up burned in roadside dumps, spewing smoke filled with toxic chemicals.

“It’s illegal, but they do it,” Palma said. “That’s what we try to avoid, those big burns.”

Palma said he thinks burning wires to extract copper must be contributing to the high asthma rates along the border. And when that pollution settles over the city, he said, it must be polluting the soil, too.

“There are businesses that are buying copper that’s been burned, and you realize it because it’s black — unlike ours, which comes out completely clean,” Palma said.

One of the factories where his company collects cables is Hikam Electronica, which is part of Japan-based Hirakawa Hewtech Corp. and says on its website that it makes a variety of electrical wires and cables.

Palma asked one of his employees to turn on the machine for a demonstration. He handed out earplugs and the hulking machine started to rumble.

The worker fed a bunch of plastic-covered wires into the machine, and seconds later bits of chopped-up copper spilled from a chute in pieces smaller than grains of rice.

From another chute, pieces of multicolored plastic rained down.

“This is business,” Palma said, holding up a coil of copper wire. “We grind it up. The machine is electric. It doesn’t give off any smoke, it doesn’t produce any pollution.”

Palma said they are experimenting with recycling the plastic by mixing the pieces into paint or using them in cinder blocks.

Green America is picking up other junk from factories, including iron cables, recyclable plastic and circuit boards. In the future, Palma said he would like to help recycle the old tires that are often dumped and burned.

“I work trying to help clean up the environment,” Palma said. “We may not be able to eliminate a large percentage of the pollution, but the little that we do is something — as opposed to people who don’t do anything.”

Lately, the government has gotten stricter and stepped up oversight of recycling businesses, Palma said. Inspectors from the state environmental agency have been visiting his company every four or five months to make sure it is complying with regulations.

Still, the recycling companies that are operating legally remain a small minority, Palma said. He doesn’t know how many have permits in Mexicali, but he guesses about 30 — “few legal, many illegal.”

He said the foreign-owned maquiladoras tend to work only with legal, established recyclers, like his company.

That’s not the case with non-industrial junk — things like old household appliances, electronics and other used items that come across the border, much of which ends up in the garbage or dumped just about anywhere in Mexicali. As Palma sees it, “there really is no regulation in the city.”

Hazardous chemicals

A man walks past a lot filled with old trucks in the Colonia Satélite neighborhood of Mexicali. Zoe Meyers/The Desert Sun

Behind their walls and guardhouses, some of Mexicali’s factories have tanks that hold industrial chemicals. At times, plants have erupted in flames and been rocked by explosions. Leaks and spills have released plumes of hazardous chemicals and sent people fleeing.

One incident occurred in 1992, when a leak at the Química Orgánica pesticide plant in Mexicali released hydrochloric acid into the air, prompting people to flee the area. The plant later closed.

Other incidents at industrial plants in Mexicali have included leaks of ammonia and fires that sent toxic chemicals up in smoke.

The accidents have prompted studies of the dangers posed by industrial plants.

Judith Ley García, a researcher at the Autonomous University of Baja California in Mexicali, has studied the risks to help authorities and companies prepare in the event of an emergency.

In one study, Ley and other researchers simulated leaks of ammonia from 18 companies that store substantial amounts of the gas, which, if inhaled, can be fatal. Mapping danger zones around those plants, they estimated that 14 percent of Mexicali’s population is exposed to risks from potential ammonia leaks, and that is considering just one of the many toxic chemicals that are used in factories along the border.

Zeroing in on ammonia, the risks are higher not only because the city has agrochemical and food plants that use the gas, but also due to the “inappropriate location or the lack of safe distances between those facilities and the population, both of which are a product of the intense and haphazard growth the city has experienced,” the researchers wrote in the study.

Ley has also examined industrial waste sites and the problem of contaminated soil in Mexicali and surrounding areas.

In a 2011 report on Mexicali titled “Atlas of Risks,” she and other researchers referred back to the 1960s, when highly salty agricultural wastewater from Arizona fouled the Colorado River, leading to stunted and dying crops downstream in the Mexicali Valley. That crisis, which contaminated farmlands and outraged Mexican farmers, touched off a diplomatic crisis and eventually led to a 1973 agreement in which the United States guaranteed that the water reaching Mexico would have an average salinity level within an accepted threshold.

Since then, the researchers said other major causes of soil contamination have emerged, including the proliferating dumps and dozens of auto-dismantling yards, which people here call yonkes, after junkyards. They counted 52 yonkes and about 70 illegal dumps in Mexicali at the time.

Those numbers have continued to grow.

The researchers said improper handling of industrial waste by factories is a problem, and that hazardous waste has ended up not only in disposal sites but also in illegal dumps, representing a “serious threat of pollution of soils and water.”

Ley and her colleagues found records showing hazardous waste has been dumped at a list of approved sites over the years, many of them in rural areas around Mexicali. They include one site where agricultural chemicals and solvents from maquiladoras were buried years ago; another where factories’ wastes were dumped; another that received metal scraps; another where truck manufacturer Kenworth disposed of fiberglass; another where hazardous industrial waste was taken until authorities found the site was polluting wells and shut it down; another waste site west of the city; and a radioactive-waste facility that was built in the 1980s.

The researchers also found that a 2004 document described a storage area for hazardous waste at the Grupo Simec steel mill.

The researchers said that in 17 locations, a total of more than 1,000 people live close to these hazardous-waste sites and face potential risks.

SOLUTIONS: 10 ideas for solving the pollution problems on the border

Toxic chemicals also pose health risks north of the border in parts of the Imperial Valley.

In Brawley, for example, the California Department of Toxic Substances Control is requiring Chevron to remediate contaminated soil and groundwater on an 11-acre property where the PureGro Company produced and stored pesticides from the 1940s until the facility closed in 2000. The agency has proposed a cleanup that would involve removing some of the tainted soil and covering up the site with a “durable liner,” but residents have protested against that plan, saying it’s not enough to protect them.

Meanwhile, some hazardous waste is regularly crossing the border from the U.S. into Mexico.

U.S. EPA records show American companies are shipping a steady stream of hazardous waste to Mexican facilities, where the relatively low costs make for a profitable business.

The EPA regulates the storage and disposal of hazardous waste under a 1976 law called the Resource Conservation and Recovery Act, and it collects annual reports from all companies that export hazardous waste.

In response to a request from The Desert Sun under the Freedom of Information Act, the EPA released dozens of reports that were submitted by companies detailing their exports of hazardous waste to Mexico between 2012 and 2016.

Steel companies in states from Alabama to Texas to Oregon reported exporting thousands of tons of furnace dust that’s left over from steelmaking. Many companies ship the dust in rail cars to Zinc Nacional in Monterrey, which recycles the dust and produces zinc oxide and zinc sulfate.

A truck drives along the Pacífico Canal toward a dump in the Mexicali Valley. Zoe Meyers/The Desert Sun

The records show American companies have also sent thousands of tons of spent lead-acid batteries to waste facilities in Mexico.

None of those hazardous waste sites is in Mexicali, though the records show that a business called Temarry Recycling in the nearby border town of Tecate receives many U.S. waste shipments. The exporters include landfills, metal-finishing businesses, cities, the U.S. Navy and American companies like Sherwin-Williams and Tesla Motors. The facility reports receiving flammable liquids, including solvents such as acetone, xylene and toluene, as well as other toxic liquids, flammable aerosols, paint, gasoline and other types of hazardous waste.

Blancafort, of the federal environment ministry, said Temarry Recycling often faces reviews by regulators because the government has received complaints about the company. He said regulators have found, however, that the company is complying with regulations.

A 1986 agreement between the U.S. and Mexican governments lays out procedures and notification requirements for cross-border shipments of hazardous waste. The two governments recognized in the pact that if cross-border shipments of hazardous waste were improperly managed, that could endanger public health, and they pledged to make additional arrangements as appropriate “to mitigate or avoid adverse effects on health, property and the environment.”

It’s not clear whether the two governments have lived up to that pledge given the limited information that’s available about how hazardous waste is handled and regulated in Mexico. And it’s an open question whether government oversight of waste sites in Mexico is sufficient to protect the health of people who live nearby.

One recent environmental fight in Mexicali illustrates the level of distrust that can surround proposals for new waste sites, even when the planned location is miles outside city limits.

In 2016, a Mexican business proposed to build a huge development in the desert southwest of Mexicali. The plan called for a solar plant, a residential area and an industrial zone where companies would store and recycle waste. The waste-storage part of the proposal alarmed environmental activists, who protested what they saw as a plan to bring in toxic waste from across Mexico and from the United States.

The project was initially dubbed “EcoZoneMx,” and later the name was changed to “Proyecto Incluyente de Mexicali,” or the “Mexicali Inclusive Project.” A representative of the company Viz Resource Management, which proposed the project, didn’t respond to a request for more information.

The company eliminated a proposal for an area to handle hazardous waste and plans to instead have recycling of conventional waste, Blancafort said. The federal government has approved a “master plan” for the development, including a solar plant.

Temoc Avila, an activist in Mexicali, said it’s a bad idea to house waste in the middle of an active earthquake zone, near an aqueduct that carries Colorado River water, and in a part of the desert where rains can send runoff coursing down from the Sierra Cucapah mountains. He said the company apparently didn’t consider the potential risks of putting waste next to the aqueduct.

“They want to bring all of the United States’ hazardous wastes to Mexicali,” Avila said. “I’m convinced it shouldn’t be built.”

Other people in Mexicali say although it wouldn’t make sense to bring more toxic waste from elsewhere, the city desperately needs to get a grip on the out-of-control dumping.

The symptoms are everywhere to see: smashed cars and piles of scrap metal in the yonkes; old box springs and shattered plastic buckets along roadsides; mounds of plastic trash and tires scattered in the desert. All of it reflects a pattern of neglect that’s adding to the pollution along the dusty, smoke-filled streets near the border.

A lawsuit and a fine

Blanca Ramírez says when there are explosions at the nearby steel mill, her house shakes. She suspects the blasts may have left cracks in the walls. Zoe Meyers/The Desert Sun

The Grupo Simec steel mill was one of three companies named in a lawsuit in 2014, when law professor Fidel Alfaro Meléndrez and a group of more than 50 university law students sued Mexican environmental authorities and accused them of failing to control pollution.

In their complaint, they wrote that the steel mill and two gas-fired power plants “are polluting the air we breathe, causing harm to the environment and society in general, translating into respiratory illnesses and losses of human lives.”

They lost the case last year. But Alfaro Meléndrez said he’s considering suing again to press for change.

The steel mill is causing severe pollution, he said. “I don’t know how that company keeps operating.”

After the lawsuit was filed, government regulators cracked down. During an inspection in September 2015, officials from the Federal Attorney for Environmental Protection, or PROFEPA, ordered the steel mill temporarily shut down and fined the company 350,000 pesos, or about $21,000, for violations including failing to properly equip the plant to control emissions.

The agency said in a statement that smoke was coming out “through doors, walls and holes, without being captured by any emission-control equipment.”

Just nine months later, the plant caught fire. TV news footage of the blaze in June 2016 showed thick smoke pouring out of the plant. The smoke spread across Mexicali, covering the city.

During the fire, Blanca Ramírez saw dark clouds swelling toward her house. She rushed to her car with her mother and drove away to safety.

The steel factory soon reopened. Even when the plant is operating normally, Ramírez said, smoke keeps drifting through her yard. And from her house, she said she sometimes hears what sound like explosions, “like a firecracker inside something.”

She doesn’t know what causes the blasts but supposes some of the crushed cars may explode if they have gas in their tanks when they reach the furnace.

The blasts are so strong the windows of her house vibrate.

Ramírez said she feels powerless.

“It’s hard not being able to do anything, not being able to control that problem,” she said. “And I think this doesn’t just affect us. It affects all of Mexicali.”

She said she wishes something would be done to cut down on the smoke billowing out of the plant. If the air were cleaner again, she said, it would be like giving back to her family a part of what was taken away from them.

Help us investigate: Do you have a tip to share about pollution along the U.S.-Mexico border? Contact reporter Ian James at ian.james@desertsun.com, 602-444-8246 or on Twitter at @ByIanJames.

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