A piece of chalk is all that it took for demonstrators to make their presence known in front of the corporate headquarters of Downer, an Australian-based construction firm, on November 24. Some of the around 150 demonstrators used it to write on the sidewalk in front of the company’s headquarters in Melbourne, Australia. One of the messages left by a protester captured their demand: “We Don’t Want Your Dirty Coal.”

The phrase refers to a roughly $12.55 billion coal mine project located over 1,000 miles north in Queensland and proposed by an Indian-based corporation named Adani Group. If constructed, it would be the largest coal mine in Australia and one of the largest in the world. The company tasked with building it? Downer.

Anneke D’emanuele, a member of the Stop Adani Melbourne collective at the protest, explained demonstrators urged Downer to withdraw from a project that would cause serious problems not only for the country, but also the planet as well.

“We sent a clear message that Adani will be bad for Australia and the future of our planet. If constructed and operating at full capacity, we will be hurtling down the road to catastrophic climate change,” she said.

In 2010, Adani Mining, a subsidiary company of Adani Group, filed an application for federal approval on a project to construct a mine in Queensland. It would primarily be in the northern section of the Galilee Basin, a profitable geological coal zone that is around 280 miles from the eastern shoreline. From 2008 to 2009, the total value of coal production in the province was over $40 billion and was projected to grow. Additionally, most of the coal produced in the province is shipped to countries across Asia—including India.

The entire proposal includes, aside from five underground mines, a 240-mile rail line to carry coal to exporting ships, an airport to fly workers in and out, and a village fitted with up to 2,000 beds. Adani doesn’t expect to complete all of this by itself, which is why Downer obtained a nearly $1.5 billion construction contract in 2014, drawing the ire of the project’s opponents.

“[Downer’s] support for the mine is support for climate vandalism,” D’emanuele said.

Jodi Magi, a coordinator with Stop Adani Melbourne, part of the Stop Adani coalition, elaborated that the action in front of Downer’s corporate offices was just one example of bringing attention to the relationship of the construction firm and Adani, “thereby negatively impacting their brand’s reputation.”

“Coal is killing people. Pollution from burning coal is the single biggest contributor to dangerous global warming,” she said.

Since signing the contract, Downer encountered legal and public issues that delayed the start of its work. Between court decisions favoring opponents of the mine and legal suits filed by indigenous and environmental groups, Adani Group constantly postponed construction of the facility to the point where it is unsure it will occur without problems.

Some of Downer’s shareholders have pressured the board to review its decision. At its annual meeting in early November, executives requested any inquiry pertaining to the coal mine be left at the end. They concluded the meeting early as some members repeatedly asked about the firm’s ties to the project.

Across Australia, the project remains a heated issue. Most Australians oppose the project, according to various polls. All of Australia’s largest four banks have declined to finance Adani’s proposal as they view coal as a financial risk. At least 10 Western banks, including Barclays and HSBC, also refused to offer any loans. Talk of providing a state loan to the project was ruled out by the federal government, leading to alternative options including a possible investment by China (as of press time three Chinese banks have declined to fund the mine).

“Opening a massive new coal pit at this point in history makes absolutely no sense on any level,” Miriam Robinson, a volunteer with the Melbourne Galilee Blockade campaign, said. “Politically it is toxic to almost all voters. It makes no economic, financial, or environmental sense.”

The climate repercussions of the project are unprecedented. The Australia Institute, a public policy think tank, released a paper in 2015 highlighting the mine alone would emit more carbon dioxide than Berlin, Paris, Toronto, or New York City per year. It would even “entirely offset Australia’s carbon reduction goals,” a concern Magi raised as well.

“To limit the impacts of climate change we need to reduce our burning of fossil fuels to zero as quickly as possible. The world can simply not afford to burn the coal from this mine,” Magi said.

There is additional concern related to the Great Barrier ReefJust nine miles off the Queensland coast, the site contains the largest coral reef in the world. Numerous animals and plants—from endangered marine turtles to the miniscule plankton—exist underwater. The reef is also listed as UNESCO World Heritage Centre Site, a distinguished honor from the United Nations for its historic value as a natural landmark.

Yet the area is under serious threat from a mixture of factors, such as climate change, as scientists have documented its gradual decline. The possibility of its famous corals going extinct does not appear far-fetched. In fact, it may occur by 2050 if no serious solution to reducing carbon emission is implemented.

Adani proposes to expand a port located near the Great Barrier Reef for ships to export, through the UNESCO site, more coal. Robinson added the coal burned over the project’s 60-year lifetime span represented “a death knell” for the Great Barrier Reef.

“Why are we polluting the top end of the already struggling Great Barrier Reef with coal dust, risks of spills and accidents, and increased disturbance to marine life so Adani can make more money than anyone could ever need?” she wondered.

That’s why the Melbourne activist Robinson found it valuable for many people, such as those at Friday’s protest, to pressure Downer to withdraw from the project. She highlighted Downer works with other industries aside from mining and the only serious penalty from leaving Adani is losing the trust of the coal industry.

“If Downer walked away it would cost them nothing, but it would be possibly a final blow to the proposal,” she said.

Activists are determined to continue their protests toward all of those tied to the project. The fact that banks and politicians have distanced themselves from the project is encouraging and Robinson believed more victories will come.

“There is a saying: ‘pick battles big enough to matter, small enough to win,’” Robinson said. “I think this is a struggle that we can and will definitely win.”

To learn more about current campaigns and upcoming actions, you can follow the Stop Adani national organization, the Front Line Action on Coal, and Galilee Blockade.

Brandon Jordan is a freelance reporter based in Queens, NY. He has written for publications such as Waging Nonviolence, The Nation, and In These Times. Follow him on Twitter @BrandonJ_R.