Promptly at noon on March 17, a heavy truck hauling a dark substance and on a dark mission pulled out of the Gaobeidian Wastewater Treatment Plant in eastern Beijing.
A wastewater treatment engineer helped a Caixin reporter identify the unusual load, which jiggled in the truck’s bed like gelatin as the driver headed down a bumpy road.
The substance was unprocessed sludge—a mucky, smelly and hazardous byproduct of the sewage treatment process. Anything less disgusting coming out of the Gaobeidian plant, the engineer said, would not have jiggled.
Gaobeidian is one of the largest wastewater plants in China and the biggest in Beijing, serving the capital’s downtown business district and industrial zones along with about 2.4 million household residents. It handles some 40 percent of Beijing’s wastewater, and has a daily wastewater capacity of about 1 million cubic meters.
The plant is one of many built over the past seven years as part of a 500 million yuan, central government push to upgrade wastewater treatment nationwide. The investment has shown some good results: The collective sewage treatment capacity in China’s counties, for example, has risen to more than 70 percent.
What’s been overlooked so far, however, is the need to complement water scrubbing with modern sludge disposal systems that protect the environment and human health.
More than ever, wastewater plants are discharging relatively safe effluent into China’s rivers, lakes and seas. But they’re often leaving sludge untreated, forcing plant operators at Gaobeidian and elsewhere to truck it away.
Where do truckers take these gooey loads of organic materials, bacteria, heavy metals and micro-organisms? A Caixin investigation found sludge from Gaobeidian has been hauled two hours away to a Hebei Province farming area and renamed “fertilizer” before being dumped on fields where corn and watermelons are grown.
Caixin followed the sludge-hauling truck bearing Beijing license plate number AK7834 and with a yellow, Gaobeidian plant tag on the windshield as the driver left the pavement at a farm in Guanjiawu Township, Yongqing County, Langfang Prefecture.
The driver steered off-road through the barren field for a few hundred meters before stopping, lifting the rear bed hatch and dumping the stinky sludge onto the bare ground.
Another truck of the same make and markings, also with a Gaobeidian windshield tag, was seen around the same time heading in the opposite direction, empty.
Residents of Anyu village who work the farm and other fields nearby later said they were told the dark substance carried by trucks was fertilizer. They also said trucks from Beijing had been depositing similar loads locally for at least two years. The dumping coincided with a village farm collective’s decision to let a non-local contractor take over management of the farm.
“Over the past two or three years, big trucks with Beijing plates have come and dumped mud,” said one villager. “We thought it was a special fertilizer that the land contractor was buying.”
A biting stench in the village air, however, conflicted with the fertilizer explanation. The area scene from the road was of soft, black sludge spread across dozens of hectares waiting for a plow. In other fields, the sludge had already been plowed under.
“These past two years, corn and watermelons have been planted on the land with the fertilizer,” the villager said. “The watermelons grew well enough, but their flavor was mediocre. Locals didn’t eat them but sold them elsewhere.”
About three months later, on June 24, Caixin returned to find clouds of flies in a reeking miasma over fields where corn plants had started poking through sludge-contaminated soil. These visits were part of a wide-ranging investigation by Caixin that determined:
- Sludge from Gaobeidian was dumped on dozens of hectares where Anyu villagers grow corn, and several hundred hectares of fields in Beijing Municipality’s Huo County, Tongzhou District. These farms have also grown melons and vegetables in the sludge-tainted soil.
- Untreated sludge has also been trucked from the Qinghe Wastewater Treatment Plant on Beijing’s northwest side and dumped in woods and on fields in the Shunyi District’s village of Mulin. Peanuts have been grown in some fields.
- Sludge that sources say came from the Xiaohongmen Wastewater Treatment Plant in southern Beijing has been dumped on dozens of hectares of woodland in the municipality’s Daxing District.
- Sludge from the Jiuxianqiao Wastewater Treatment Plant in northeast Beijing has been dumped in forests and on agricultural land in Daxing District’s town of Caiyu. Sludge has been plowed under on dozens of hectares.
- Altogether, Caixin confirmed the regular use of five sludge dumping sites and two transportation routes traveled by trucks from Beijing wastewater plants.
A source close to the Beijing Drainage Group, a municipal government corporation that runs the city’s sewage treatment plants, told Caixin that most of Beijing’s untreated sludge has been dumped in rural areas for years, first at mining sites and later on farm fields.
“Years ago, gravel pits or abandoned mine shafts were sought out,” the source said. “In recent years, dump sites have gotten farther away, some even as far as Hebei Province.”
How Toxic?
Beijing’s wastewater treatment facilities extracted a combined 2,400 tons of sludge every day back in 2011, or about 800,000 tons annually, according to a Beijing Drainage official who was quoted in April that year by the official Beijng Daily newspaper. The official said all city sludge is properly treated, and none presents a pollution hazard.
But sources interviewed by Caixin contradicted those claims. They said the amount of unprocessed sludge discharged by Beijing's treatment plants is high, perhaps equal to several hundred thousand tons per year. Moreover, at some plants sludge handling treatment has yet to be put to use.
A 2011 research paper by Tan Guodong, a doctoral candidate at Beijing Forest University, and Li Wenzhong, a research fellow at Beijing Water Science & Technology Institute, estimated the city’s annual output at more than 500,000 tons of untreated sludge.
What’s the environmental impact of sludge dumping? And how does it affect people? On Tan's list are short- and long-term risks including pathogenic bacteria, parasites and heavy metals.
These days, Beijing's sewage has lower levels of industrial wastes such as heavy metals thanks to government efforts to clean up the environment by relocating factories outside the city. Nevertheless, Tan said, heavy metals from previously dumped sludge still pose threats to local soil and groundwater.
Urban waste researcher Professor Zhou Yuwen at the Beijing University of Technology said hazardous polychlorinated biphenyls, phthalic acid and dioxins found in untreated sludge pose a long-term threat to the environment and the food chain.
“The contents of sludge are complex,” he said. “It's not simply countryside manure.”
Tan described sludge as “a concentration of all the dirtiest things in wastewater.”
Proper sludge processing uses dehydration and fermentation to break down the waste, sometimes to provide useful byproducts such as methane fuel and fertilizer. But in China, Tan said, most sewage plant sludge is inadequately treated, if at all.
Business Stinks
Beijing’s illegal sludge disposal problem first took center stage in October 2010 when local businessman He Tao was sentenced to three and a half years in prison and fined 30,000 yuan. Court findings published in the People’s Court Daily said He’s company was a contractor in charge of disposing sludge from several wastewater plants operated by Beijing Drainage.
He was found guilty of illegally dumping about 6,000 tons of sludge into gravel pits in the village of Shang’an and elsewhere around the town of Yongding in the municipality’s Mentougou District.
Authorities were first alerted by villagers who complained about an intense stench surrounding the pits, which turned out to be illegal dump sites.
Chinese Academy of Meteorological Sciences researchers concluded that this dumping had a serious environmental impact. They found that the sludge-filled gravel pits contained dangerous levels of heavy metals, ammonia nitrogen and fecal coliform. Also lurking in the muck was an infectious pathogen called Shigella bacteria, which can lead to dysentery.
Researcher Chen Tongbin of the Institute of Geographic Sciences and Natural Resources, Chinese Academy of Sciences, said in their joint papers that pathogens in sludge pose serious health dangers and if improperly handled can even trigger disease epidemics.
Meteorological science researchers estimated the environmental costs associated with He’s sludge contract would exceed 100 million yuan, including 80.3 million yuan to clean up the gravel pits.
He’s case opened a window to the business side of sludge dumping that’s been profitable for years, as wastewater facilities outsourced sludge disposal to contractors.
He’s Beijing Huanxing Environmental Protection Science and Technology Co. Ltd. opened in 2003 and subsequently signed sludge disposal agreements with the Qinghe and Jiuxianqiao plants. Between October and July 2006, the court found, the company dumped about 6,000 tons of sludge into gravel pits, paying pit operators 70 to 100 yuan per truckload.
Officials from Beijing Drainage and the sewage plants were cleared of wrongdoing. But Beijing Drainage admits on its website that contractors since 2011 have been hired for sludge transportation services.
Caixin learned that, with the exception of several, Beijing Drainage-owned trucks used by Qinghe plant operators, most of the city’s sludge has been hauled away by contracting companies.
In the search for sludge dumping grounds, sources said, contractors have shifted in recent years from gravel pits to less expensive farm fields and forests. Tan said landfills were used in years past when “the total quantity of wastewater was small," but today landfill operators refuse sludge.
Moreover, according to one source, “farmers are generally unwilling to allow sludge dumping on land they contract out. Only on collective farm or forest lands that are not allocated to a single farmer are people willing to make short-term profits and disregard the long-term impact.”
An internal Beijing Drainage document obtained by Caixin indicates that wastewater facilities have paid 1 yuan per ton per kilometer traveled in sludge transportation fees over the past two years.
“Wastewater treatment plants effectively control costs by outsourcing their sludge,” said the insider. “Land contractors who accept sludge charge dumping fees of 20 to 35 yuan per ton, and transportation contractors charge 35 to 50 yuan per ton.”
But it seems no one in the business factors in the costs of environmental damage or the health effects for villagers or consumers who eat food grown in sludge.
Hollow Rules
Sludge disposal contracting and similar practices appear to conflict with the Beijing Municipal Water Pollution Prevention Ordinance, which says wastewater treatment operators are responsible for preventing every kind of pollution associated with sewage processing.
The rule apparently hasn’t worked in Beijing. And similar regulations have failed to prevent illegal sludge dumping in major cities across China, several cases of which have come to light in recent years.
This year in Nanjing, for example, about 120 tons of untreated sludge was reportedly dumped on a mountain on the nights of March 19 and 20. Officials said the culprit was Nanjing Changhua Renewable Resource Recycling Co. Ltd., a company doing business with the Nanjing Jiangxinzhou Wastewater Treatment Plant.
Officials determined the Nanjing plant operators had directly and illegally disposed of about 34,000 tons of sludge over the course of almost a year.
Shanghai’s government is currently investigating a case of illegal dumping linked to the nearby city of Suzhou. The case dates to April 2012, when authorities say Li Bin and three accomplices used a boat to make eight, sludge-haul trips from Suzhou to a dump site in a conservation area's forest in Shanghai’s Qingpu District.
The sludge came from Suzhou’s Wuzhong District Urban Wastewater Treatment Plant. Each of the four suspects was found guilty of polluting the environment, fined and sentenced to a three year-six month prison term.
One of the most recent reports hails from Wuhan, where in May sludge from the city’s Hanxi and Sanjintan sewage plants was found stinking up two pits the size of soccer pitches in the village of Liugutang.
Indeed, the Wuhan Evening News said, a city wastewater treatment official has claimed most local sludge has been regularly dumped on idle land outside the city but that no one notices.
Since few wastewater treatment plants in China have the right equipment for sludge treatment, these dumping reports are apparently just the tip of the iceberg.
Since 2010, a Ministry of Environmental Protection (MEP) regulation has been in force that says sludge processing equipment must be designed, built and put into operation whenever a sewage treatment plant is built or refurbished. It also required all existing plants to have sludge equipment operating by 2012.
That deadline came and went, and today the sludge problem persists. Even plants that installed sludge processing machines have reportedly failed to use them effectively.
In April 2012, a State Council report said less than 25 percent of all sludge from urban wastewater treatment plants had been safely disposed of in 2010.
A December 2011 report on China’s Urban Water Supply and Drainage Industry Development, issued by the China Urban Water Association, said less than 10 percent of the nation's sludge was being safely handled. It also said treatment procedures and equipment were seriously behind the times.
There are no official statistics that quantify China’s sludge output or disposal. But Fu Tao, an environment professor at Tsinghua University, estimates annual output of about 28 million tons of wet sludge, or about 76,600 tons daily nationwide. And in 2010 Zhao Yingmin, director of the Department of Science, Technology and Standards at the Ministry of Environmental Protection (MEP), estimated the nation’s annual sludge production at 30 million tons.
The Ministry of Housing and Urban Development (MOHURD) says 3,451 treatment plants were operating in prefecture-level cities and counties as of March with a combined daily capacity of 145 million cubic meters of wastewater.
Fu said MOHURD’s China Urban Construction Statistical Yearbook says the nation’s output is 3.41 tons of wet sludge per 10,000 tons of treated wastewater, which would mean sewage plants handled less than 14 million tons of wet sludge in 2011. “This leaves us no choice but to doubt” the MOHURD data, he said.