Plastic Fantastic? Indonesia plans to turn plastic waste into road tar

Next to China, Indonesia is the world’s second biggest ocean plastic polluter. Will an initiative to build “plastic roads” help reduce the country’s plastic waste? Environmentalists cast some doubts.

Plastic on Bunaken Beach
Plastic waste on Bunaken Beach Sulawesi, Indonesia. Image: Silke Baron, CC BY-NC-ND 2.0

Indonesia has a serious plastic waste problem.

According to the country’s environment ministry, Indonesians consume a million plastic bags per minute, and rank second in the world (behind China) for dumping plastic into the sea.

Plastic waste lines roadsides and river banks, and has devastating effects on marine life. The unsightly mess also threatens to “ruin” Indonesia’s tourism industry, Coordinating Minister for Maritime Affairs Luhut Binsar Pandjaitan told reporters earlier this year.

In response, the government has pledged to devote $1 billion per year to reducing plastic and other marine waste by 70 per cent, a commitment reiterated by President Joko Widodo at the recent G-20 meeting.

In addition to public education campaigns and a pilot program introducing charges for plastic bags, the government is rolling out a new waste management strategy: Turning discarded plastic into road-building material.

So-called plastic roads — which add shredded, melted plastic waste to the road-tar mix — are touted as being stronger, cheaper and more durable than conventional roads, while also providing a solution for disposing of tons of plastic that would otherwise sit in landfills or clog waterways.

Some environmentalists, however, are skeptical, claiming that the environmental benefits of such roads are overstated, while the overall approach fails to deal with the root problem of over-consumption of single-use plastic.

In accordance with the principle of precaution, a technology that has not been adequately studied should not be applied widely, but used on a laboratory scale.

Sutasurya, Alliance for Zero Waste Indonesia (AZWI) 

Seeking solutions

Indonesia has already carried out its first plastic-road trial, at Udayana University in Bali, where a 700-meter (0.43-mile) stretch of plastic road was laid on July 29.

Now, officials plan to use the material on roads in the Javanese cities of Jakarta, Bekasi and Surabaya, with preparations scheduled to start within weeks.

The plastic-road project is a joint effort of the Coordinating Ministry for Maritime Affairs and the Ministry of Public Works and Housing. According to Safri Burhannudin, a deputy minister at the coordinating maritime ministry, these two agencies will be working with the Indonesian Plastic Recycling Association (Adupi) to collect and sort waste in 16 large cities.

“In this waste reduction effort, the first stage is public education, then we ask for the support of the Ministry of Public Works. We hope the use of plastic waste for asphalt will become an appropriate solution for the problem of waste in Indonesia,” Burhanuddin said in a press release.

“Every kilometer of road, with a width of seven meters, requires between 2.5 to 5 tonnes (2.75-5.5 tons) of mixed plastic waste. So you can imagine if the results of this study are implemented across Indonesia, which has thousands of kilometers of roads,” said Danis Hidayat Sumadilaga, head of the ministry of public works’ Agency for Research and Development.

Plastic waste in Indonesia is estimated to reach 9.52 million tonnes by 2019, or 14 per cent of the country’s total waste. With each kilometer of road requiring 2.5 to 5 tonnes of plastic, plastic waste could be used to pave 190,000 kilometers of road.

In addition, the resulting material is stickier than traditional asphalt. This, Sumadilaga explained, means stronger and more stable roads: “Stability increases by around 40 per cent. This makes the performance even better.”

The downside

Building roads with plastic isn’t a new idea. The process was developed around 15 years ago in India, where there are already more than 21,000 miles of plastic-tar roads.

These roads, which have proven remarkably durable in the face of floods and heat, have many fans. They also have detractors among the conservation community.

Since Indonesia announced plans to follow in India’s footsteps, local researchers and activists like David Sutasurya, director of the Bioscience and Biotechnology Development Foundation (YPBB) have gotten in touch with their counterparts in India, such as Dharmesh Shah of Global Alliance for Incinerator Alternatives (GAIA).

According to Sutasurya, these India-based activists highlighted a number of shortcomings in the actual implementation of road-building plans.

For example, while plastic tar was initially proposed as a solution for plastic that would otherwise be wasted, India’s road quality standards actually require the use of plastic types — LDPE and HDPE — that are already sought-after for recycling. Meanwhile, other materials such as the laminated plastics commonly used for packaging still accumulate as waste.

Some efforts have been made to develop techniques for incorporating layered and laminating packaging into road tar, but again, Indian authorities only allow limited amounts of very thin laminated plastic to go into the mix.

Another potential problem with this technology is micro-plastic pollution. Plastics are melted to form a sticky coating over bitumen, but don’t actually break down. Thus, weathering of the road over time can degrade plastic into micro-particles that enter the ecosystem.

Activists in India have also raised concerns about the possibility that such roads could introduce hazardous chemicals into the environment, since the tar is processed at a maximum temperature of 160 degrees Celsius — hot enough to melt plastic but not enough to ensure various toxins are degraded.

Thus, when exposed to light, heat and water, the plastic in such roads has the potential to leach chemicals into the surrounding ecosystem in the same way that any plastic waste does.

Sutasurya of YPBB, who is also a member of Alliance for Zero Waste Indonesia (AZWI) said that while there is not yet firm evidence that plastic roads leach hazardous materials, that does not necessarily mean they are safe. It simply means that research has not yet been done on the subject.

“In accordance with the principle of precaution, a technology that has not been adequately studied should not be applied widely, but used on a laboratory scale,” he said.

Catur Yudha Hariani, activist with Bali’s Environmental Education Center for (PPLH) agreed that plastic tar must be approached carefully if the plan is to use it for big projects. She also warned that while plastic roads may prove to be a novel solution for disposing of used plastic, they won’t solve the problem of over-consumption.

“The point is that if you want to reduce plastic, this must be done by changing mindsets and behavior patterns,” said Hariani, emphasising the importance of raising awareness about waste as well as the need for policies that make plastic expensive and require companies accept back the plastic waste their products create.

This story was reported by Mongabay’s Indonesia team and was first published on our Indonesian site on Aug. 2, 2017. Republished with permission.

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